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1
Bellomo, Vito. "Damage tolerance analysis for Blackshape BS 115 programme, EASA CS VLA & CS-23." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8070/.
Full textAbstract:
The thesis project has been developed in partnership with the Design Department of Blackshape Spa, a carbon – fiber ultra – light airplane company in Monopoli (Bari, Italy).
The main goal is the assessment of a starting point for a damage tolerant concept during the design and certification phases of the Blackshape BS 115 airplane, with respect to EASA CS VLA & CS 23 Regulations. This approach has been carried out starting from an initial literary review as far as the way of modeling composites fractures is concerned.
Further on, three finite element models have been generated and implemented in order to simulate defects occurring during manufacturing and service phases. At last, the procedures of non - destructive inspections have been taken into account, in order to establish how to investigate primary structures defects and delaminations during maintenance.
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Mikulik, Zoltan Mechanical & Manufacturing Engineering Faculty of Engineering UNSW. "Application of fracture mechanics to predict the growth of single and multi-level delaminations and disbonds in composite structures." Publisher:University of New South Wales. Mechanical & Manufacturing Engineering, 2008. http://handle.unsw.edu.au/1959.4/41560.
Full textAbstract:
The high stiffness to weight ratio and fatigue resistance make carbon fibre composites suitable for both military and large civil aircraft. The limited ability of current numerical methods to capture the complex growth of damage in laminated composites leads to a conservative design approach applied in today??s composite aircraft structures. The aim of the presented research was to develop an improved methodology for the failure prediction of laminated composites containing delaminations located between arbitrary layers in the laminate, and to extend the investigations to composite structures subjected to barely visible impact damage (BVID). The advantages of fracture mechanics-based methodologies to predict interlaminar failure in composite structures were identified, from which the crack tip element (CTE) approach and the virtual crack closure technique (VCCT) were selected for assessment. Extensive validation of these fracture mechanics methods is presented on a number of composite structures ranging from coupons to large stiffened panels. It was shown that the VCCT was relatively insensitive to the crack front mesh size, whilst predictions using the CTE methodology were significantly influenced by the element size. Based on the obtained results modelling guidelines for the VCCT and CTE were established. Significant contribution of this research to the field of the analysis of composite structures was the development of a novel test method for the evaluation of embedded single and multi-level delaminations. The test procedure of the single delamination specimen was proposed as an analogous test to conventional compression experiments. The transverse test overcame the inherent problems of in-plane compression testing and produced less scatter of experimental measurements. Quantitative analysis of numerical results employing the validated finite element modelling approaches showed that the failure load and location were in agreement with experiments. Furthermore, new modelling techniques for composite structures containing BVID proposed in this research produced good correlation with test data from the compression after impact (CAI) test. The study of BVID provided a significant contribution toward the knowledge of the applicability of implicit FE solvers to predict failure of CAI specimens as well as the criticality of centrally impacted specimens.
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Ozcan, Riza. "Fatigue And Fracture Analysis Of Helicopter Fuselage Structures." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615497/index.pdf.
Full textAbstract:
In this study a methodology is developed for the fatigue and fracture analysis of helicopter
fuselage structures, which are considered as the stiffened panels. The damage tolerance
behavior of the stiffened panels multiaxially loaded is investigated by implementing virtual
crack closure technique (VCCT). Validation of VCCT is done through comparison between
numerical analysis and the studies from literature, which consists of stiffened panels
uniaxially loaded and the panel with an inclined crack. A program based on Fortran
programming language is developed to automate the crack growth analysis under mixed
mode conditions. The program integrates the prediction of the change in crack propagation
direction by maximum circumferential stress criterion and the computation of energy release
rate by VCCT. It allows reducing the computation time for damage tolerance evaluation for
mixed mode cases through finite element analysis and runs the procedure file of
MSC.Marc/Mentat for numerical analysis and the program generated by Patran Command
Language (PCL) of MSC.Patran for remeshing. The developed code is verified by comparing
the crack growth trajectories obtained by numerical analysis with the experimental studies
from literature. A submodeling technique is utilized to analyze a particular fuselage portion of
helicopter tail boom. Effects of different skin/stringer configurations of the helicopter fuselage
structure on stress intensity factor are studied by means of the developed program. Fatigue
crack growth analysis is performed by using stress intensity factors obtained from numerical
analysis and fatigue propagation models proposed in literature.
4
Durand, Camille. "Etude thermomécanique expérimentale et numérique d'un module d'électronique de puissance soumis à des cycles actifs de puissance." Thesis, Valenciennes, 2015. http://www.theses.fr/2015VALE0007/document.
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De nos jours, la durée de vie des modules d’électronique de puissance est désormais limitée par les technologies standards de conditionnement, telles que le câblage par fils et le brasage. Ainsi une optimisation des technologies actuellement employées n’est pas suffisante pour satisfaire les futures exigences de fiabilité. Pour dépasser ces limites, un nouveau module de puissance remplaçant les fils de connexion par des clips en cuivre a été développé. Ce design innovant vise à améliorer la fiabilité du module puisqu’il empêche la dégradation des fils de connexion, constituant bien souvent la principale source de défaillance. La contrepartie de ce gain de fiabilité réside dans la complexification de la structure interne du module. En effet, l’emploi d’un clip en cuivre nécessite une brasure supplémentaire fixant le clip à la puce. Ainsi, le comportement thermomécanique et les différents modes de rupture auxquels le composant est soumis lors de son utilisation doivent être caractérisés. Cette étude utilise la simulation numérique pour analyser avec précision le comportement de chaque couche de matériaux lors des cycles actifs de puissance. De plus, une étude de sensibilité à la fois expérimentale et numérique concernant les paramètres de tests est réalisée. Les zones critiques du module ainsi que les combinaisons critiques des paramètres de tests pour les différents modes de rupture sont mis en évidence. Par ailleurs, une analyse en mécanique de la rupture est conduite et la propagation des fissures à différentes zones clés est analysée en fonction des différents paramètres de tests. Les résultats obtenus permettent la définition de modèles de prédiction de durée de vie<br>Today a point has been reached where safe operation areas and lifetimes of power modules are limited by the standard packaging technologies, such as wire bonding and soft soldering. As a result, further optimization of used technologies will no longer be sufficient to meet future reliability requirements. To surpass these limits, a new power module was designed using Cu clips as interconnects instead of Al wire bonds. This new design should improve the reliability of the module as it avoids wire bond fatigue failures, often the root cause of device failures. The counterpart for an improved reliability is a quite complicated internal structure. Indeed, the use of a Cu clip implies an additional solder layer in order to fix the clip to the die. The thermo-mechanical behavior and failure mechanisms of such a package under application have to be characterized. The present study takes advantage of numerical simulations to precisely analyze the behavior of each material layer under power cycling. Furthermore an experimental and numerical sensitivity study on tests parameters is conducted. Critical regions of the module are pointed out and critical combinations of tests parameters for different failure mechanisms are highlighted. Then a fracture mechanics analysis is performed and the crack growth at different locations is analyzed in function of different tests parameters. Results obtained enable the definition of lifetime prediction models
5
Islam, Mohammad Majharul. "Global-local Finite Element Fracture Analysis of Curvilinearly Stiffened Panels and Adhesive Joints." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/38687.
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Global-local finite element analyses were used to study the damage tolerance of curvilinearly stiffened panels; fabricated using the modern additive manufacturing process, the so-called unitized structures, and that of adhesive joints. A damage tolerance study of the unitized structures requires cracks to be defined in the vicinity of the critical stress zone. With the damage tolerance study of unitized structures as the focus, responses of curvilinearly stiffened panels to the combined shear and compression loadings were studied for different stiffenersâ height. It was observed that the magnitude of the minimum principal stress in the panel was larger than the magnitudes of the maximum principal and von Mises stresses. It was also observed that the critical buckling load factor increased significantly with the increase of stiffenersâ height.
To study the damage tolerance of curvilinearly stiffened panels, in the first step, buckling analysis of panels was performed to determine whether panels satisfied the buckling constraint. In the second step, stress distributions of the panel were analyzed to determine the location of the critical stress under the combined shear and compression loadings. Then, the fracture analysis of the curvilinearly stiffened panel with a crack of size 1.45 mm defined at the location of the critical stress, which was the common location with the maximum magnitude of the principal stresses and von Mises stress, was performed under combined shear and tensile loadings. This crack size was used because of the requirement of a sufficiently small crack, if the crack is in the vicinity of any stress raiser. A mesh sensitivity analysis was performed to validate the choice of the mesh density near the crack tip. All analyses were performed using global-local finite element method using MSC. Marc, and global finite element methods using MSC. Marc and ABAQUS. Negligible difference in results and 94% saving in the CPU time was achieved using the global-local finite element method over the global finite element method by using a mesh density of 8.4 element/mm ahead of the crack tip. To study the influence of different loads on basic modes of fracture, the shear and normal (tensile) loads were varied differently. It was observed that the case with the fixed shear load but variable normal loads and the case with the fixed normal load but variable shear loads were Mode-I. Under the maximum combined loading condition, the largest effective stress intensity factor was very smaller than the critical stress intensity factor. Therefore, considering the critical stress intensity factor of the panel with the crack of size 1.45 mm, the design of the stiffened panel was an optimum design satisfying damage tolerance constraints.
To acquire the trends in stress intensity factors for different crack lengths under different loadings, fracture analyses of curvilinearly stiffened panels with different crack lengths were performed by using a global-local finite element method under three different load cases: a) a shear load, b) a normal load, and c) a combined shear and normal loads. It was observed that 85% data storage space and the same amount in CPU time requirement could be saved using global-local finite element method compared to the standard global finite element analysis. It was also observed that the fracture mode in panels with different crack lengths was essentially Mode-I under the normal load case; Mode-II under the shear load case; and again Mode-I under the combined load case. Under the combined loading condition, the largest effective stress intensity factor of the panel with a crack of recommended size, if the crack is not in the vicinity of any stress raiser, was very smaller than the critical stress intensity factor.
This work also includes the performance evaluation of adhesive joints of two different materials. This research was motivated by our experience of an adhesive joint failure on a test-fixture that we used to experimentally validate the design of stiffened panels under a compression-shear load. In the test-fixture, steel tabs were adhesively bonded to an aluminum panel and this adhesive joint debonded before design loads on the test panel were fully applied. Therefore, the requirement of studying behavior of adhesive joints for assembling dissimilar materials was found to be necessary. To determine the failure load responsible for debonding of adhesive joints of two dissimilar materials, stress distributions in adhesive joints of the nonlinear finite element model of the test-fixture were studied under a gradually increasing compression-shear load. Since the design of the combined load test fixture was for transferring the in-plane shear and compression loads to the panel, in-plane loads might have been responsible for the debonding of the steel tabs, which was similar to the results obtained from the nonlinear finite element analysis of the combined load test fixture.
Then, fundamental studies were performed on the three-dimensional finite element models of adhesive lap joints and the Asymmetric Double Cantilever Beam (ADCB) joints for shear and peel deformations subjected to a loading similar to the in-plane loading conditions in the test-fixtures. The analysis was performed using ABAQUS, and the cohesive zone modeling was used to study the debonding growth. It was observed that the stronger adhesive joints could be obtained using the tougher adhesive and thicker adherends. The effect of end constraints on the fracture resistance of the ADCB specimen under compression was also investigated. The numerical observations showed that the delamination for the fixed end ADCB joints was more gradual than for the free end ADCB joints.
Finally, both the crack propagation and the characteristics of adhesive joints were studied using a global-local finite element method. Three cases were studied using the proposed global-local finite element method: a) adhesively bonded Double Cantilever Beam (DCB), b) an adhesive lap joint, and c) a three-point bending test specimen. Using global-local methods, in a crack propagation problem of an adhesively bonded DCB, more than 80% data storage space and more than 65% CPU time requirement could be saved. In the adhesive lap joints, around 70% data storage space and 70% CPU time requirement could be saved using the global-local method. For the three-point bending test specimen case, more than 90% for both data storage space and CPU time requirement could be saved using the global-local method.<br>Ph. D.
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Zhang, Li. "Structural study of the interaction between poxvirus-encoded cc chemokine inhibitor vcci and human mip-1beta." Diss., Texas A&M University, 2008. http://hdl.handle.net/1969.1/85901.
Full textAbstract:
Chemokines (chemotactic cytokines) comprise a large family of proteins that
recruit and activate leukocytes, giving chemokines a major role in both immune response
and inflammation-related diseases. Viral CC chemokine inhibitor (vCCI) is a poxvirus
encoded protein that has been shown to bind tightly and inhibit the action of many CC
chemokines. This function suggests that vCCI could be explored as an antiinflammatory
therapeutic, a possibility that has been supported in mouse studies. The
structure of vCCI in unbound form was determined by others, but to date no structure
has been reported of bound vCCI. We report the NMR structure of vCCI in complex
with the human CC chemokine MIP-1[beta]. The non-aggregating MIP-1[beta] variant MIP-1[beta]
45AASA48 was used in this complex to allow sufficiently high concentration at pH 7 to
carry out the solution structure determination. A combination of NOE distance
restraints, torsion angle restraints, and residual dipolar coupling were used to determine
the structure of the complex, which also required protein deuteration due to its relatively
large size (34kDa). The structure shows that MIP-1[beta] binds to vCCI with 1:1 stoichiometry, forming a complex of 311 amino acids. vCCI uses residues from its [beta]-
sheet II to interact with a surface of MIP-1[beta] that includes residues adjacent to its Nterminus,
as well as residues in the 20's region, and the 40's loop. The structure of the
MIP-1[beta]-vCCI complex reveals for the first time the regions of each protein involved in
the interaction, and allows a greater understanding of the strategy used by vCCI to
tightly bind numerous chemokines, while retaining selectivity for the CC chemokine
subfamily.
7
Larrinaga, Felix. "Efficient VCT-based strategies for mobile communication networks." Thesis, Staffordshire University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285984.
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8
Adkins, Michael Frank. "An Evaluation of the Vccs Developmental Math Redesign from A Faculty Perspective." W&M ScholarWorks, 2017. https://scholarworks.wm.edu/etd/1499449918.
Full textAbstract:
Community colleges face an environment that requires them to increasingly focus on completion while simultaneously maintaining open admissions (Sydow & Alfred, 2013). Developmental math courses are a linchpin in improving college completion because approximately 60% of community college students are placed into developmental math courses, yet very few of those students make it through developmental courses and on toward degree completion (Bailey, 2009; Developmental Math Redesign Team, 2010). In 2009, the Virginia Community College System (VCCS) embarked on a system-wide redesign of developmental math courses (Developmental Education Task Force, 2009). However, such large-scale system change means challenges and previous experience highlights that approximately 50% – 80% of change initiatives fail to meet their goals (Black, 2013). This study evaluated the change process used to implement the VCCS developmental math redesign. A uniquely created survey based on Kotter’s (2012) change model was used to determine if faculty observed sound change practices at their institutions during the redesign. Using confirmatory factor analysis, the findings suggest that faculty saw evidence of Kotter’s (2012) change model in the implementation of the redesign. There were differences in how faculty perceived the change processes based on different demographic characteristics. There was evidence that Kotter’s (2012) model was fully implemented in the redesign, and there were some significant differences in faculty perceptions of Empowerment. This study concluded that positively framing the results of the redesign at the system level could have improved student outcomes and that it would be wise for colleges to assess the change processes they use.
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Merkouris, Panagiotis. "Article 31(3)(c) of the VCLT and the principle of systemic integration." Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/477.
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The proliferation of international courts and tribunals combined with the expansion of the areas and density of regulation of international law has given rise to a debate on the issue of fragmentation of international law. Within this context and as a possible response to this fear of fragmentation, the issue of interpretation with specific reference to Article 31(3)(c) of the Vienna Convention on the Law of Treaties has come to the forefront. The overarching aim of the present thesis entitled ‘Article 31(3)(c) of the VCLT and the Principle of Systemic Integration’ is to provide a comprehensive analysis of the content and the function of Article 31(3)(c) both as a conventional and as a customary rule (i.e. as principle of systemic integration). To this end, the thesis adopts a two-pronged approach. In the first Part of this thesis the analysis is based on the text of the provision itself, both on its written and unwritten elements (intertemporal law considerations). This analysis demonstrates that a proper understanding of Article 31(3)(c) leads us to the adoption of the proximity criterion as the only appropriate in the application of Article 31(3)(c). Having concluded the textual analysis, the thesis then, in the second Part, considers Article 31(3)(c) from a different vantage point. It examines Article 31(3)(c) from the more general perspective of the system as a whole and analyses what the effects of more systemic considerations to the content of Article 31(3)(c) are. Within these parameters two issues arise: i) The principles of conflict resolution, which the thesis proves can be applied, in certain scenarios, in the interpretative process of Article 31(3)(c) and ii) more importantly the notion of interpretation of customary law. The relevant Chapter establishes that customary international law can be the object of interpretation and in such an interpretation Article 31(3)(c), as custom, plays a pivotal role. Through this approach, both from a textual and a systemic perspective, the thesis offers a new and complete understanding of Article 31(3)(c) in all its manifestations and spheres of application.
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Lantz, Karl, and Martin Johansson. "Modeling of a step motor for position feedback in a climate system." Thesis, University West, Department of Technology, Mathematics and Computer Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-374.
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Maama, Lineo Bernadette. "Factors affecting AIDS orphans' from accessing voluntary counselling and testing (VCT)." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1046.
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The study seeks to explore and identify factors that prevent AIDS orphans in presenting themselves for Voluntary Counselling and Testing (VCT). Socio-cultural factors, notably, stigma and the resultant discrimination by community members, have been presented by many researchers as the main aetiological factors that hinder the use of VCT by AIDS orphans. It is on the basis of this that this study was conducted to identify factors that hinder AIDS orphans from accessing VCT. The study used a qualitative approach following an explorative and descriptive, contextual research design and was conducted at Ubuntu Education Fund, Port Elizabeth. Purposive sampling was used to determine a sample of AIDS orphans. Participants of the study had to be orphaned as a result of AIDS, isiXhosa-speaking, between 12-17 years, living in the care of a primary care-giver and had not presented themselves for VCT. Data was collected by means of semi-structured interviews. Semi-structured interviews are suitable in cases where the researcher is interested in an issue that is complex or personal (De Vos, Strydom, Fouche and Deloport, 2005). Data was analyzed according to the framework provided by Tesch (1990) as described in Creswell (2003). The major findings of this study were that people are locked in a ‘poverty-of-the mind cycle’, in respect of HIV and AIDS, and this is exacerbated by educational impoverishment and general poverty. The recommendations that emanated from this study are made from policy and service delivery perspectives. It is recommended that in order for AIDS orphans to access VCT they should be developed and empowered through sustainable programmes that enhance their capacities to the outmost realization of their potential. It is also recommended that health and other professionals should encourage AIDS orphans and community members to present themselves for VCT and thus curb the spread of HIV and AIDS.
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August, Yolande Margaret. "A study of the effectiveness of the VCT service at the NMMU." Thesis, Nelson Mandela Metropolitan University, 2006. http://hdl.handle.net/10948/470.
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The students are the future economic backbone of the country and it is essential that measures are taken to reduce the number of new HIV infections in this segment of the population. Free voluntary counselling and testing for HIV was introduced at the Nelson Mandela Metropolitan University as one of the prevention strategies to curb the spread of HIV. This service has grown steadily over the years but strategies need to be formulated and implemented to improve the existing service and thereby increase the utilisation of the testing service. This treatise takes the form of an investigative survey involving literature review and a survey of all the individuals who utilised the VCT service over a three month period. The author has attempted to portray the general views and best practices of experts in the field of VCT service delivery. The identified best practices were used as an assessment tool to determine to what extent the VCT service at the NMMU complies with national and international standards. The quantification of these insights must be viewed with caution since the survey sample was relatively low due to time constraints. It has been shown that the VCT service at the NMMU largely complies with national and international standards although several recommendations have been presented for consideration.
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Obiajulu, Anthony. "Knowledge ,attitude and practice of voluntary counseling and testing (VCT) for HIV/AIDS amongst the health professionals in Umpumulo Hospital , Mapumulo , Ilembe District , Kwazulu-Natal Province." Thesis, University of Limpopo (Medunsa Campus), 2009. http://hdl.handle.net/10386/209.
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Thesis(M Med.(Family Medicine)--University of Limpopo, 2009.<br>The impact of HIV/AIDS on the health sector and the health professionals that work in it is huge. This impact has contributed to the continuing attrition of health professionals in South Africa. Voluntary Counseling and Testing (VCT) has a central role to play in the response to these problems both at the level of the health sector in general and most especially at the level of the individual health professional. Thus, understanding factors that affect the practice of VCT amongst this group of professionals is crucial in South Africa‟s quest to reverse these negative trends. AIM The aim of this study was to determine the level of knowledge, to access and understand the attitude and practice of VCT for HIV/AIDS amongst the health professionals in a rural district Hospital and to make recommendations in order that appropriate intervention strategies may be instituted. METHODS A descriptive cross-sectional quantitative study design was used in which data was collected using a self-administered questionnaire. The study population included all the health professionals working in the hospital at the time of the study but excluded those who were on leave or absent from duty during the period of data collection. Informed consent was obtained from each participant. Data was captured and analyzed using the SPSS version 15.0 (SPSS Inc, Chicago, Illinois, USA).
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RESULTS There was a very high level of knowledge, a moderately supportive attitude and a moderately high level of practice of VCT amongst the study participants. Divorced/separated respondents to this study had more supportive attitude towards VCT than their single colleagues. Age was found to have a very weak but positive correlation to attitude score. There was no significant difference in knowledge and attitude scores between those who practiced VCT and those who did not. CONCLUSION Health professionals understand the importance of VCT as an HIV preventive behavior but there remains some VCT knowledge, attitude and practice concerns together with other determinants of VCT behavior that needs to be addressed.
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Lindgren, Mathias. "Practical Verification of Stateful Embedded C Code using Finite State Machines and VCC." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-272106.
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Vehicles in the 21st-century are becoming more and more dependent on embedded software systems for navigation, system control, monitoring, and entertainment. Manufacturers of cars have also over the years been put under more and more safety regulations and as such, some of these systems are of a safety critical nature and undergo rigorous reliability testing. Some automotive manufacturers have been investigating the use of Formal Verification as a strategy in ensuring reliability and safety. Previous work has resulted in techniques and methods for automated Formal Verification to aid in this endeavour. However, problems still exist with verifying software that is stateful, i.e. where the output of the system depends on its internal state. To tackle the problems with describing stateful requirements of programs, a model of writing requirements as Finite State Machines is presented. A case study looking at real world requirements on stateful C code was performed. Verification with previously used tools was successful when writing the requirements in the new style. Future possible improvements and shortcomings are identified.<br>Fordon under 2000-talet blir mer och mer beroende av inbäddade programvarusystem för navigering, systemkontroll, sensorer, och underhållning. Tillverkare av bilar har under åren också ställts inför fler och fler regleringar gällande säkerhet och mer resurser har lagts på rigorösa tillförlitlighetstester. Vissa fordonstillverkare har undersökt användandet av formell verifiering som en strategi för att säkerställa tillförlitlighet och säkerhet. Tidigare arbete har resulterat i tekniker och metoder för automatiserad formell verifiering för att hjälpa till i denna strävan. Emellertid finns det fortfarande problem med att verifiera mjukvara som är tillståndsstyrd, dvs där systemets effekter beror på dess interna tillstånd. För att tackla problemet med att beskriva krav med en tillståndsstyrd karaktär, föreslås en ny modell för att beskriva säkerhetskrav som ändliga automater. En fallstudie som tittar på verkliga krav på tillståndsstyrd C-kod utfördes. Verifiering med olika verktyg var framgångsrik när kraven skrevs i denna nya stil. Framtida möjliga förbättringar och brister identifieras.
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Baloyi, Gift Rirhandzu. "Loss to initiation on antiretroviral therapy (ART) after voluntary counselling and testing (VCT)." Thesis, University of Limpopo (Medunsa Campus), 2011. http://hdl.handle.net/10386/506.
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Thesis ((MSc(Med)(Pharmacy))--University of Limpopo (Medunsa Campus), 2011.<br>Background: Anecdotal evidence from fixed Voluntary Counselling and Testing (VCT)
centres within the public sector indicates, that many patients are lost in the transition from
VCT to Human Immunodeficiency Virus (HIV) care and treatment. The actual number of
patients who are eligible for antiretroviral ttreatment (ART) after a positive HIV test, but who
do not visit the antiretroviral (ARV) clinic to initiate ART, is currently not known. The need to
identify the extent of this problem was therefore evident.
Objectives: To investigate and describe the procedures and records used at the VCT
centres under study. To identify the proportions of patients who fail to proceed through the
different steps of the process from VCT to initiation on ART within a period of six months. To
make recommendations for interventions aimed at improving the tracking of patients from
the VCT entry point to ART initiation.
Methods: The study was conducted as an operational research project at Odi and Stanza
Bopape VCT centres. The design of the study was descriptive. Data were collected
retrospectively and prospectively over a period of four months. Operational procedures and
documentation systems at both VCT centres were observed. The records of all patients who
tested HIV positive from 1 April 2009 to 30 June 2009 at Odi and Stanza Bopape VCT
centres were identified from the VCT registers and selected for the study. Patients who were
eligible for ART were identified based on their CD4 count. Eligible patient names were crossreferenced
against the SOZO system (electronic patient database) to determine whether
they had attended their pre-treatment visits at the ART clinic and whether ARV medicines
had been dispensed to them for the first time. Where there was no proof that the patient
attended the pre-treatment visits or finally accessed ART at an ARV clinic within six months,
the patient was regarded as lost to initiation on ART.
Results: The results obtained from the observational phase of the study showed differences
in the procedures followed at the two VCT centres. At Odi VCT centre, patients referred for
VCT by medical doctors only had an ELISA test and had to return on a different date for the
ELISA test results, while patients visiting the VCT centre voluntarily first had a Rapid test
and if positive they had an ELISA test on the same day. At Stanza Bopape VCT centre,
patients referred by doctors and patients visiting the VCT centre voluntarily had a Rapid test
and an ELISA test after a positive Rapid test. The patients at Odi had their CD4 test results
interpreted by the nurse at the VCT centre while at Stanza Bopape the results were
interpreted by the doctor at the ARV clinic.
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The study included a cohort of 743 patients who tested HIV positive from April 2009 to June
2009 at Odi and Stanza Bopape VCT centres. Of these patients 344 tested at Odi VCT
centre and 399 were tested at Stanza Bopape. The majority of patients at the two VCT
centres were female (55% at Odi VCT centre and 59% at Stanza Bopape VCT centre),
unemployed and single.
At both VCT centres, patients were expected to return for collection of CD4 results within two
weeks of the HIV test. At Odi VCT centre, 159 (49.4%; n=322) patients did not return to
collect their CD4 results. Of those who returned, only 41.1% (67; n=163) returned within one
month. At Stanza Bopape VCT centre 52.8% (210; n=399) patients did not collect their CD4
results. Of the patients who collected their CD4 count results, 51.3% (97; n=189) collected
within one month. The Fisher’s exact test revealed no statistically significant difference
(P=0.410) between the two VCT centres in terms of patients who returned for their CD4
results collection and those who did not return.
More than half of the patients with accessible CD4 counts at Odi presented late for VCT.
This was shown by 65.4% (n=275) of patients with CD4 count 200 cells/mm3 during HIV
diagnosis. At Stanza Bopape VCT centre 46.6% (n=386) also had CD4 count 200
cells/mm3. The difference in terms of late presentation between the patients from the two
clinics was statistically significant (P<0.001; Fisher’s exact test).
The ART initiation rate at both VCT centres was found to be low. More than half of the
patients eligible for treatment (CD4 200 cells/mm3) at both VCT centres did not initiate
ART. This was shown by 59.4% (n=180) of patients at Odi VCT centre and 67.8% (n=180) of
patients at Stanza Bopape VCT centre who did not initiate ART. There was no significant
difference (P=0.317; Fisher’s exact test) between the two VCT centres in terms of the
patients who did not initiate ART.
Conclusion: A high percentage of patients who presented for VCT and were eligible for
treatment were lost to initiation on ART. The majority of these patients did not return to
collect their CD4 results and thus were lost immediately after VCT. These results suggest a
need for an urgent intervention that will improve ART uptake.
Recommendations: Patients referred by doctors for VCT at Odi VCT centre should have a
Rapid test, and if positive they should have an ELISA and CD4 test on the same day to
prevent the loss of patients before they even identify their HIV status.
The option of a ‘one stop’ VCT and immediate CD4 results, should be further explored due
to the unacceptable patient default rates at both VCT centres. A CD4 count machine which
x v
will provide results immediately on the same day of the test should be utilised.
There must be sufficient personnel and equipment to follow-up on patients who do not return
for their CD4 results, pre-treatment counselling and ART.
The SOZO system should be integrated between the VCT centres and the ARV clinics to
improve the flow of patient information between the VCT centre and the ARV clinic.
A qualitative study should be conducted to explore reasons for patients not returning to
collect their CD4 results.
Key words: VCT; loss to initiation; non-uptake; lost in transition; HIV and AIDS
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Fergutz, Laurinei. "Avaliação do network calculus e VCC na caracterização de vídeo MPEG para sistemas multimídia." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/908.
Full textAbstract:
O padrão de codificação MPEG contém algoritmos que analisam a redundância temporal e espacial do vídeo. Devido a esta característica, grandes variações na taxa de dados são observadas numa sequência de vídeo. Deste modo, os sistemas multimídia apresentam dificuldades no planejamento, projeto e utilização dos recursos necessários para a reprodução adequada do vídeo. A proposta deste trabalho é avaliar o uso das abordagens "Network Calculus" (NC) e "Variability Characterization Curve" (VCC) na caracterização de vídeos MPEG, fornecendo informações úteis para a composição de sistemas multimídia. Usualmente, o NC é uma teoria utilizada para se obter limitantes de desempenho em redes de pacotes, enquanto o VCC apresenta técnicas para se obter limitantes inferior e superior de desempenho de um sistema computacional. Neste trabalho, porém, tanto o NC quanto o VCC são utilizados para definir limitantes de desempenho na forma de parâmetros a serem usados na caracterização de vídeo. Além disso, uma variação do VCC usando curvas aproximadas é utilizada neste trabalho para avaliação da economia de recursos. Adicionalmente aos métodos NC e VCC, é proposto um novo método para agregar informação ao conjunto de parâmetros utilizados na caracterização de vídeo. De forma a avaliar os métodos em diversas condições, são realizados testes com vídeos em diferentes configurações e conteúdos, usando os padrões MPEG-2, MPEG-4, H264/AVC. O resultado da aplicação destes métodos é um conjunto de parâmetros que podem ser utilizados para caracterizar os vídeos e indicar as particularidades e exigências que cada vídeo impõe aos sistemas multimídia. Além disso, uma ferramenta computacional para avaliação desta caracterização é proposta e implementada.<br>The MPEG video coding standard has algorithms for analyzing temporal and spatial video’s redundancies. Therefore, a great variation of data rate is observed in a video sequence. Consequently, planning, design and utilization of the necessary resources for playing video is not an easy task in multimedia systems. This work evaluates the application of Network Calculus (NC) and Variability Characterization Curve (VCC) approaches in MPEG video characterization by providing useful information to setup multimedia systems. Usually, NC theory is applied to obtain performance bounds for packet networks while VCC provides techniques to obtain lower and upper performance bounds for a computational system. However in this work, both NC and VCC are applied to define performance limits expressed as parameters to be used in this work to evaluate resource savings. In addition, a new method is proposed by adding information to the set of parameters used for video characterization. For evaluating these methods in several conditions, a set of tests in accomplished in different configurations with videos MPEG-2, MPEG-4 and H264/AVC. The result is a set of parameters that can be used to characterize videos and point out particularities and requirements imposed by each video to multimedia systems. Finally, a computational tool for evaluating this characterization is also proposed and implemented.
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Murali, Dilip Venkateswaran. "Verification of Cyber Physical Systems." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23824.
Full textAbstract:
Due to the increasing complexity of today\'s cyber-physical systems, defects become inevitable and harder to detect. The complexity of such software is generally huge, with millions of lines of code. The impact of failure of such systems could be hazardous. The reliability of the system depends on the effectiveness and rigor of the testing procedures. Verification of the software behind such cyber-physical systems is required to ensure stability and reliability before the systems are deployed in field. We have investigated the verification of the software for Autonomous Underwater Vehicles (AUVs) to ensure safety of the system at any given time in the field. To accomplish this, we identified useful invariants that would aid as monitors in detecting abnormal behavior of the software. Potential invariants were extracted which had to be validated. The investigation attempts to uncover the possibility of performing this method on existing Software verification platforms. This was accomplished on Cloud9, which is built on KLEE and using the Microsoft\'s VCC tool. Experimental results show that this method of extracting invariants can help in identifying new invariants using these two tools and the invariants identified can be used to monitor the behavior of the autonomous vehicles to detect abnormality and failures in the system much earlier thereby improving the reliability of the system. Recommendations for improving software quality were provided. The work also explored safety measures and standards on software for safety critical systems and Autonomous vehicles. Metrics for measuring software complexity and quality along with the requirements to certify AUV software were also presented. The study helps in understanding verification issues, guidelines and certification requirements.<br>Master of Science
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Norin, Max. "Uttorkning av högpresterande betonggolv : Råd och rekommendationer vid mätning av RF." Thesis, Uppsala universitet, Byggteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326060.
Full textAbstract:
A development project was undertaken within the consortia formed by Polygon and AK-konsult. The aim of this project was to map out the impact of humidity leakages on the result of humidity measurements in concrete slabs according to the so-called RBK-method. It is behind the idea of this development project that the main purpose of this thesis can be derived from. For instance, an evaluation of already existing data material from a RBK-measurement has been done. A method has been retrieved in order to compare the trend of the measured values of the relative humidity with the trend of the expected values of the relative humidity during the drying process. The main goal has been to implement this method as an instrument to analyze the actual drying process. A survey study was undertaken among the employees of the consortia in order to point out the differences that arise during the installation of the measurement equipment prior to measurement according to the RBK-method. The result of the survey has been summarized and analyzed in purpose to catch a wider glimpse over the different kinds of variables that might have an impact on the result from a RBK-measurement. The outcome from the study of the existing measurement data shows that some of the measurement spots tends to dry out faster than the calculated drying process, while other spots indicates a slower drying process. Three of them actually pointed out that they were under humidity, which implies that they still hadn’t reached the stadium of moisture equilibrium with the concrete. The main reason behind the observed discrepancies might have its explanation in the fact that measurement wholes that have been subjected to a big humidity leakage. The consequence of measurement spots subjected to big humidity leakages, is that the measured value of the relative humidity turns out to be much lower than the actual level of the relative humidity in the concrete. An observation has been made in the plausibility analysis and in the Vaisalaproject that the normative equilibrium time exceeds the number of three days that’s been ordained by RBK. A further study of the normative equilibrium time can thereby be recommended to clarify if it still can be compatible with the different kinds of concrete classes of today.
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Williams, Leilanie. "Barriers and enablers to acceptance of voluntary counseling and testing (VCT) services by youth males." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/19894.
Full textAbstract:
Thesis (MPhil)--University of Stellenbosch, 2007.<br>ENGLISH ABSTRACT: Voluntary Counseling and Testing (VCT) is considered an important component of the
South African government’s response to the HIV/AIDS pandemic. Despite of this, the
numbers of South Africans who have accessed VCT remains low. Pregnant women in
antenatal clinics remain the primary recipients of HIV testing since it is routinely offered
to them at antenatal clinics. Figures from antenatal clinics constitute the most important
source of HIV/AIDS statistics in South Africa. Targeting women at antenatal clinics
perpetuate the stereotypes that women are solely responsible for reproductive health
issues or, that they are to be blame for the mounting HIV infections. These beliefs
exacerbate the culminating violence against women.
According to observation, active involvement of male youth in reproductive health at the
Rosedale Clinic situated in Uitenhage, a town in the Eastern Cape, appears to be very
limited. This might be as a result of traditional beliefs declaring reproductive health a
primarily female domain. Active involvement of males in reproductive health is
considered to have positive health outcomes both for themselves, and their partners. The
purpose of this study is thus to encourage males served by the Rosedale clinic to become
more actively involved in one aspect of reproductive health, namely voluntary counseling
and testing (VCT). The study aims to find out which factors constitute barriers and
enablers to VCT acceptance by male youth.
Semi-structured, face-to- face interviews were conducted in September 2006 with
eighteen males, 18 to 25 years, to determine from their perspective what constitute
barriers and enablers to HIV test acceptance by males. These participants were recruited
from two well-known rugby clubs in Uitenhage, located in the Eastern Cape. In addition,
a focus group discussion was conducted with four males recruited at a graduate
development programme hosted in Uitenhage in order to explore common themes
emerging from interviews and the discussion. A pervasive, psychologically rooted fear; and possible low perception of risk emerge
from this study as main barriers to HIV testing. Negative perceptions regarding service
delivery in the public health sector constitute another barrier to HIV testing. The
possibility of teasing, a common phenomenon amongst rugby players but not exclusive to
them, exacerbates peer pressure thus possibly contributing to low levels of HIV test
acceptance among these males. Increased HIV test acceptance is associated with
increased opportunities of exposure to HIV testing opportunities, for example at
awareness campaigns. Access to medical aid and income is also associated with an
increased likelihood of HIV testing since most males prefer accessing HIV testing
services in the private sector. Convenience and ease of access to HIV testing services are
important when these males consider going for HIV testing.<br>AFRIKAANSE OPSOMMING: Vrywillige Berading en MIV Toetsing, een aspek van reproduktiewe gesondheid, word
beskou as ‘n belangrike komponent van die Suid-Afrikaanse regering se strategie teen
MIV/VIGS. Ongeag van hierdie feit is ‘n groot aantal Suid-Afrikaners nog nie getoets vir
MIV nie. Swanger vrouens word op ‘n daaglikse basis hierdie toets aangebied as deel
van roetine ondersoeke. Syfers vanaf pre-natale klinieke vorm die hoofbron van Suid-
Afrika se HIV/VIGS statistieke. Die feit dat swanger vrouens die hoofteikengroep is vir
MIV toetsing dra by tot stereotipes wat daartoe lei dat vrouens primêr verantwoordelik is
vir die behoud van reproduktiewe gesondheid; en dat hulle beskou word as die
hoofverdagtes in die toenemende oordrag van MIV. Laasgenoemde beskuldiging vererger
geweld teen vrouens.
Volgens waarneming by Rosedale publieke kliniek geleë in Uitenhage, ‘n dorp in die
Oos-kaap, is veral jeugdige mans se betrokkenheid in reproduktiewe gesondheid uiters
minimaal. Dit kan moontlik wees omdat reproduktiewe gesondheid tradisioneel as ‘n
vroulike domein beskou word. Aktiewe betrokkenheid van beide mans en vrouens in
reproduktiewe gesondheid het positiewe gesondheidsuitkomste vir beide partye tot
gevolg. Die doel van hierdie studie is dus om jongmans wie deur die Rosedale kliniek
bedien word aan te moedig om meer sigbaar te word in reproduktiewe
gesondheidskwessies; met die oog op een aspek daarvan naamlik, vrywillige berading en
MIV toetsing. Die studie poog dus om uit te vind watter struikelblokke jeugdige mans
weerhou van MIV toetsing en; watter faktore mans aanmoedig om vir die toets te gaan.
Semi-gestruktureerde, aangesig-tot- aangesig onderhoude is in September 2006 met 18
mans, vanaf die ouderdomme 18 tot 25 jaar, gevoer. Hierdie mans was tydens die studie
rugbyspelers vanuit twee welbekende rugbyklubs op die dorp. ‘n Addisionele fokus groep
is verder gevoer met manlike studente wie ten tye van die studie aan ‘n
ontwikkelingsprogram vir gradueerders deelgeneem het op die dorp. Hierdie fokusgroep
is geloods om soortgelyke temas vanuit die onderhoude en die bespreking te ondersoek. Die studie toon dat ‘n diepgewortelde, sielkundige vrees; en moontlike lae bewustheid
van persoonlike risiko die twee vernaamste struikelblokke is vir MIV toetsing.
Negatiewe sienings rakende die publieke gesondheidssektor kan moontlik bydrae tot
weerstand teen MIV toetsingsdienste. Tergery, ‘n bekende verskynsel onder rugbymans,
maar nie slegs beperk tot diè groep nie, dra by tot groepsdruk en weerhou moontlik
menige mans van MIV toetsing. Diegene in die studie wie alreeds vir MIV getoets is
geniet toenemende blootstelling aan MIV toetsingsgeleenthede; bv tydens
bewusmakingsveldtogte geloods òf by die werk òf tersiêre instellings. Toegang tot ‘n
mediese fonds; en ‘n inkomste is moontlike bepalende faktore sienende dat meeste
respondente gesondheidsdienste in die privaatsektor verkies. Gerieflike toegang tot MIV
toetsingsdienste word deur sommige mans as belangrike beskou wanneer hulle MIV
toetsing oorweeg.
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Frifelt, Henrik, and Wille Larsson. "Uttorkning av betongprover : För betong med fokus på lågt vct, samt avjämningsmassans påverkan av uttorkningen." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-43622.
Full textAbstract:
Moist-related damages correspond with 80 % of all damage in construction. A part of this moist-related damage occurs when the surface is applied to prematurely on concrete, such as with shallow foundations and intermediate floors. New cast concrete contains a lot of construction water, which must be allowed to dry out in order to avoid damage. In which case the level of relative humidity, RH, depends on the material combined with the concrete. The time until it reaches correct level of relative humidity is often long and is mainly dependent on the composition of the concrete and the climate. The length of drying time is a problem in today’s construction industry where prefabricated structural components and more efficient working practices have led to a reduced construction time. Nowadays the concrete is often coated with a layer of screed before the coating is applied. Overall, there are few measuring guides for how much impact the screed has on the concrete’s dehydration. Specifically, the problems are based surrounding the measurement and calculation methods for dehydration of concrete. There is currently no reliable calculation program for determining the drying time of the concrete. Also, wrongly performed relative humidity measurements often lead to an excessively low RH value. The goal of this work is that, through an experimental study, we can discover how the drying of concrete with three different water-cement ratios differs in comparison with the programs TorkaS 3.2 and 2.0. The aim is also to see if a layer of screed provides moisture to the concrete and thus inhibiting its drying speed. The result shows that there is a marked difference between the measured RH from borehole measurement and calculation programs TorkaS. The greatest error is detected on concrete with water-cement ratio 0, 50 and 0, 38. For 0, 50 has TorkaS 3.2 and 2.0 a margin of error around 4 % and 6 % against the measured values. The conclusion is that the programs TorkaS 3.2 & 2.0 have underperformed with calculations in all three cases and have underestimated the drying time of the concrete. However, the results have shown a big difference between the two programs. TorkaS 3.2 with the correction factor has a significantly lower differential than TorkaS 2.0 has towards the experimental results. The conclusion is that the programs are not reliable for precise estimation in the drying process of the concrete, but should be considered more as guidance. Furthermore, the study revealed that a layer of screed could extend the drying process of a concrete foundation with water-cement ratio of 0, 38 & 0, 50. Regarding the concrete with the water-cement ratio of 0,34, the layer of screed developed a higher level of moisture. This leads to a longer time before the concrete dries out.
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Mutwali, Reem. "Socio-demographic characteristics and HIV testing in Omdurman National Voluntary Counseling and Testing (VCT) in Sudan by Reem Mutwali." Thesis, UWC, 2008. http://hdl.handle.net/11394/2874.
Full textAbstract:
>Magister Scientiae - MSc<br>The identification of the association between socio-demographic characteristics and HIV was found to be a useful tool in determining the important risk factors in Sudan. In this study, the relationship(s) between HIV test results and the demographic characteristics such as gender, age, residence area, employment, education, marital status and religion in Omdurman, Sudan were investigated. The data were collected from patients visiting Omdurman National Voluntary Counseling and Testing (VCT) Centre from April 2005 to April 2006. The study sample was represented by 320 patients. Tables were used in the data analysis to present the distribution of the participants by the result of HIV test and demographic factors; odds
ratios were also obtained from these tables. The Chi-square test was used to test the association between each socio-demographic factor and the result of HIV test; the Pvalue obtained from this test was measured at a significance level of 0.05. Finally, the joint effect of all demographic factors on HIV test results was tested using logistic regression. A significant association between socio-demographic characteristics and HIV test results was observed. It showed a higher incidence rate in females, middle-aged, married, employed and Christian individuals. HIV was also found to be higher in urban areas than
in rural areas. The lower incident rate was observed among educated individuals.
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Arcidiacono, Diletta. "VCC, citolisina di Vibrio cholerae,promuove secrezione di cloruro dalle cellule intestinali e produzione di citochine TH2 nei mastociti." Doctoral thesis, Università degli studi di Padova, 2008. http://hdl.handle.net/11577/3425205.
Full textAbstract:
Cholera has long been considered a classic paradigm of a non-inflammatory toxigenic diarrhoea until Vibrio cholerae infection was found to induce a TH2-type of immune profile and the recruitment of inflammatory cells in the intestinal mucosa (Mathan MM, 1995; Qadri F, 2000).
Recent reports indicate increased levels of inflammatory mediators in patients infected by Vibrio cholerae that occur in parallel with recruitment of innate immune cells, including mast cells and neutrophils, in the crypt and villus lamina propria (Qadri F, 2004).
Enteropathogenic Vibrio cholerae can elaborate different exotoxins: cholera toxin (CT), zonula occludens toxin and a membrane damaging toxin, referred to as haemolysin or Vibrio cholerae cytolysin (VCC).
VCC is a water soluble toxin secreted as a 79 kDa inactive pro-hemolysin (Alm RA, 1988; Yamamoto K, 1990), which is proteolytically cleaved within its N-terminal part (Nagamune K, 1997) to generate the mature toxin of 63 kDa.
In cholesterol-and ceramides-rich membranes (Zitzer A, 1999) VCC forms heptameric channels, with a moderate anion preference, responsible for vacuolization and eventual lysis of several cell types in culture (Coelho A, 2000; Figueroa-Arredondo P, 2001; Moschioni M, 2002; Pantano S, 2006).
VCC is believed to contribute to the development of cholera diarrhoea (Ichinose Y, 1987).
On the basis of its channel property and considering that the majority of the diarrhogenic toxins affect chloride secretion in the intestine (Laohachai KN, 2003), we have investigated whether VCC was able to promote an efflux of chloride from intestinal epithelial cells.
We find that the hemolysin induces an efflux of chloride from intestinal epithelial cells; consequently it might either cause diarrhoea per se, in the non producing cholera toxin strains, or contribute to cause diarrhoea when the toxin is present.
Considering the recent demonstration of the abundance of mast cells in cholera patients and on the basis that no other bacterial factors have been identified as immune modulator so far, we decided to address the possibility that VCC could be such a factor, by evaluating its ability in activating mucosal mast cells.
Here we suggest that VCC could contribute to the T helper 2 (TH2) response seen in the natural infection; acting through TLR2, VCC enhances mast cells secretion of IL-4, IL-6 and TNF-alpha by 330-, 290- and 550-fold respectively.
Moreover, VCC-induced cytokine production is dependent on increased cytosolic Ca2+ and on the presence of the Src family kinases Lyn and Fyn, known to be required for FcepsilonRI-dependent activation of mast cells.
These findings strongly suggest that VCC has a pro-inflammatory activity promoting a TH2-type immune profile.
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Metin, Dennis, and Dylan Hashem. "Mätning av fuktnivåer i betonggolv." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-8862.
Full textAbstract:
Examensarbetet redovisar försök utförda på betonggolv i syfte att studera betongens uttorkningsprocess. Testresultaten jämförs med beräkningar utförda i BI Dry och TorkaS. Betongen i testerna utsattes för fuktbelastning av olika grader och skeden. Detta skulle modellera att betong på byggen exponeras för väder och vind. Examensarbetet innehåller både litteraturstudier gällande betongensuttorkningsprocessen och tester. TorkaS 3.2, BI Dry 2.0 samt HumiGuards webbaserade beräkningsprogram användes för att beräkna uttorkningsprocessen och göra en analys av uppmätt data.<br>The thesis reports experiments performed on the dehydration process of moisture in concrete floor specimens. The aim is to study the RF-values in concrete exposed to humidity and for comparing actual measurements with calculation results from software. Investigation is made on the drying concrete affected by moisture at different levels and stages modelling for cases where concrete is usually exposed to weather conditions for fairly long periods before a controlled drying environment is achieved. The thesis was performed by using literature studies and tests. For each concrete slab specimen moisture controls were mounted sampling data which was implemented into the calculation program. TorkaS 3.2, BI Dry 2.0 and HumiGuard webbased calculation software was used for modelling the drying process and it is reported with graphs in the work.
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Sikasote, Janet Precious Banda. "Effect of voluntary counselling and testing and a negative HIV result on risk behaviour : a qualitative longitudinal study in a Zambian mining community." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4441.
Full textAbstract:
Background: Countries in sub-Saharan Africa are scaling up access to Voluntary Counselling and Testing (VCT) services as a strategy for HIV prevention, treatment, care and support. The international and national push to achieve targets for anti-retroviral therapy scale up has emphasised VCT as an entry point to treatment, with follow-up mostly directed at those who test positive. Yet over 60% of those testing are HIV negative. Limited understanding of how HIV voluntary counselling and testing, and receipt of a negative result impact on sexual behaviour has resulted in underdeveloped support for those testing HIV negative. Aims: To gain the perspective of those who have tested HIV-negative on the following: (1) the decision making process that precedes attendance for voluntary counselling and testing; (2) how voluntary counselling and a negative test result influence sexual behavioural intentions and reported subsequent behaviour; and (3) support systems and networks that would enhance the respondent’s ability to remain HIV negative. Method: Qualitative longitudinal study utilising semi-structured interviews, six months apart, with people who have tested negative and three one-off focus group discussions with counsellors. Participants were purposively sampled from VCT centres in two mining towns in Zambia. Interviews were digitally recorded, transcribed verbatim and analysed thematically with the aid of the qualitative data analysis software, Nvivo7. Cross-sectional analysis of all data sets was conducted and paired transcripts were analysed longitudinally to assess change over time. Results: Forty-two HIV-negative people were interviewed, with thirty-one returning for the follow-up interview (74% return rate). VCT was perceived as ‚testing for HIV‛. Before attending VCT most participants had gone through a protracted period of angst, resulting in a resolution to reduce number of partners, use condoms or abstain from sex. Counselling affirmed life choices, rather than initiating them. Although perception of the risk of HIV increased, misconceptions about HIV transmission persisted post-counselling. The negative test result provided impetus and resolve to implement or maintain life change. Themes identified were: (1) recognising personal susceptibility to HIV infection; (2) emotional and cognitive engagement with the problem of testing; (3) a driving need to know status (regardless of test result); and (4) empowerment and being in control providing the ability to plan for the future. Analysis of post-test support needs revealed two further themes: (1) reinforcement of behaviour change through additional knowledge, supportive networks, and life-skills training; and (2) access to recreational activities. There was no reported post-test increase in unsafe sexual behaviour among those that returned for the follow-up interview. Focus group findings reinforced those from interviews. Conclusions: This study has shown that in this population of people who tested HIV-negative: 1. the majority made life changes before attending VCT and used VCT to know their status 2. counselling consolidated pre-test decisions about risk behaviour and testing provided motivation to adopt safer behaviour and to maintain previous low- or no-risk behaviour and 3. there is a felt need for post-testing recreational activities, further HIV/AIDS education and participation in HIV prevention activities. Recommendations include: (1) the promotion of community-based interactive one-to-one and group information, education and communication (IEC) (to aid understanding and progression to the point where testing appears to be of optimum benefit) ; (2) referral to post-test support options such as support groups and inclusion on a text messaging list should be made available; and (3) post-test intervention strategies, for example, provision of result-specific IEC materials and active involvement in prevention activities should be developed and evaluated.
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Subramanian, Sriram. "Software Performance Estimation Techniques in a Co-Design Environment." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1061553201.
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Lönnquist, Anders. "The economic relevance of multivariate GARCH models : CCC, DCC, VCC MGARCH(1,1) covariance predictions for the use in global minimum variance portfolios." Thesis, Örebro universitet, Handelshögskolan vid Örebro Universitet, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-67989.
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Markarian, Philippe Daniel. "Family Farming, Biodiesel and Social Inclusion In Bahia: Assessing Brazil's National Program for the Production and Use of Biodiesel." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36944.
Full textAbstract:
The present research evaluates the social inclusion component of the Brazilian National Program for the Production and Use of Biodiesel’s (PNPB) by studying its impact on the livelihoods of family farmers in the country’s Northeast region of Bahia. The overall objective is to critically analyze the social sustainability aspect of the program by including different dimensions of social exclusion in its analysis. More specifically, this thesis examines the PNPB’s effectiveness in helping family farmers in Bahia achieve positive livelihood outcomes. In terms of theoretical perspective, the Sustainable Livelihoods Framework (SLF) is employed while existing research and government data are analyzed using a descriptive method. The findings of this thesis indicate that the PNPB is predominantly designed in economic terms, largely ignoring the multi-dimensional nature of social exclusion. In this sense, the results suggest that the lack of success of the program in the country’s Northeast region can be in part explained by its failure to adopt coherent and sustainable strategies that go beyond market insertion and income generation. In particular, the research demonstrated that the PNPB’s lack of participatory approach and the absence of social and cultural considerations, along with inadequate technical extension services, hampered the program’s success in the region. Based on these results, this research highlights the need for a broader approach when it comes to promoting social inclusion, as well as the importance of taking into account and developing the cultural, social and political capital of family farmers in Bahia. In this sense, this thesis emphasizes the importance of recognizing that social exclusion is a complex and multi-faceted phenomenon, which calls for improving the ways with which we evaluate and deepen the understanding of the livelihoods of family farmers in Bahia.
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Bucyana, Allan. "The influence of specialised HIV/AIDS sites on first time clients' initiative to seek VCT services : a case of Nkumba University students, Uganda." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6869.
Full textAbstract:
Thesis (MPhil (Industrial Psychology. Africa Centre for HIV/AIDS Management))--University of Stellenbosch, 2011.<br>ENGLISH ABSTRACT: Although VCT has been recognized for its importance in HIV prevention and control, there are several matters of concern surrounding it that potentially limit its uptake. Clients' selective behavior in tandem with service provider and operating environment factors determine uptake of VCT service. This study sought to contribute knowledge on the influence that specialized HIV/AIDS sites have on first time clients' initiative to seek VCT services in comparison with the general health care sites. The study also analyzed factors that determine clients' preference of VCT access point.
The study was done within a student population of Nkumba University in Entebbe municipality, Uganda. A sample of students to fill the study questionnaire was selected using a simple random sampling method from a population frame established from a class identified haphazardly. Four focus group discussions were done: two of the groups participants were stratified as students' male and female groups and were selected using convenient sampling from the sampling frame. The other FGDs were done with two groups of nurse counselors – one from a general health care site while the other was from a specialized VCT site, selected purposively.
Specialized VCT sites had a higher frequency of first student clients than general health care sites. Results however indicated that though the perception of service providers' attitude and availability of trained councilors affected their choice, there was no significant difference between specialized and general VCT sites in terms of first time clients' preference. Reasons for preference of site differed. Specialized sites were preferred because they are perceived to offer better quality service owing to their concentration on VCT services, but shunned by others for lack disguise. Conversely, respondents revealed that there is disguise at general health j sites which enhances confidentiality and anonymity thereby curbing clients fears of being identified making it easier for first time clients to go to these sites for VCT.<br>AFRIKAANSE OPSOMMING: Alhoewel vrywillige raadgewing en toetsing (VRT) erken is vir sy belangrikheid met betrekking tot MIV voorkoming en beheer, is daar verskeie kwessies daaraan verbonde wat die gebruik daarvan kan beperk. Kliënte se selektiewe gedrag saam met diensverskaffers en omgewingsfaktore bepaal die gebruik van VRT dienste. Hierdie studie het gepoog om kennis by te dra oor die invloed wat gespesialiseerde MIV/Vigs toetsingsterreine het op eerstelinge se inisiatief om VRT dienste te soek in vergelyking met algemene gesondheidssorgterreine. Die studie het ook faktore geanaliseer wat kliënte se voorkeur van VRT terreine bepaal.
Die studie is binne 'n studente populasie van Nkumba Universiteit in Entebbe Munisipaliteit, Uganda, uitgevoer. 'n Steekproef van studente om die vraelyste in te vul is geselekteer deur die eenvoudige toevalmonster metode te gebruik van 'n populasie raam geskep van 'n klas was lukraak geidentifiseer is. Vier fokusgroepe het plaasgevind: twee waar deelnemers as manlike en vroulike studentegroepe gestratifiseerd was en geselekteer deur gerieflike steekproeneming van die steekproefraam. Die ander fokusgroepe was twee groepe van verpleegster beraders – een van 'n algemene gesondheidssorgterrein en die ander van 'n gespesialiseerde VRT terrein, doelbewus geselekteer.
Gespesialiseerde VRT terreine het 'n hoër frekwensie van eersteling student-kliente as algemene gesondheidssorgterreine. Uitslae het aangedui dat hoewel die persepsie van diensverskaffers se houdings en beskikbaarheid van opgeleide beraders hul keuse geaffekteer het, dat daar geen betekenisvolle verskil was tussen gespesialiseerde en algemene VRT terreine in terme van eerstelinge se voorkeur. Redes vir voorkeur van terrein het verskil. Gepesialiseerde terreine is verkies weens die persepise dat hulle 'n beter kwaliteit diens lewer weens hul konsentrasie op VRT dienste, maar deur ander vermy was weens gebrek aan vermomming. Omgekeerd het respondente aan die lig gebring dat daar wel vemomming by algemene gesondheidssorg terreine is wat
vertroulikheid en anonimiteit verhoog en kliënte se vrese verminder wat dit makliker maak vir eerstelinge om na hierdie terreine vir VRT te gaan.
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Onyeani, Onyema Awa. "The obligation of host states to accord the standard of 'full protection and security' to foreign investments under international investment law." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/16087.
Full textAbstract:
The analysis of this thesis is to examine whether foreign investors can fully rely on the standard of FPS in BITs for the protection of their investments in the territories of host States which has been mandated to States by international law. This question cannot be answered without giving insights into the content and structure of the origin of FPS standard and adopts a dynamic based-perspective of the interpretation of FPS under VCLT 1969, encompassing the relationship between FPS and CIL. It investigates the tribunals' interpretation of the clause using case laws and literatures to identify and explore the underlying explanatory process behind tribunals' case findings and outcomes. The study examines the critical realism that the obligation of FPS standard does not place absolute liability to a host State, rather the exercise of a reasonable degree of vigilance. It evaluates the controversy surrounding the relationships between FPS and FET, and illuminates on how the two standards may co-evolve which has led to various arbitral tribunals' divergence opinions interpretation of the two principles. The evaluation of the application of FPS to digital assets is dynamic in this research as it addresses the nature of threats investors face globally today over cyber attacks of digital investments. The thesis also emphasis on balancing up investors' rights and obligation, which explains the measures that States can apply to prevent foreign investors from engaging in illegitimate activities. Having look at all these issues, circumstances, and the controversies surrounding FPS standard, the result found is that there is a existence of a gap in this area of the law, that would mean that foreign investors cannot completely rely on the principle of FPS for the protection of their investments in the territories of the host unless this lacunae is properly filled by both the States and arbitral tribunals, especially the tribunals' interpretative meaning of the standard of FPS.
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Akanlu, George Bruno. "Willingness to pay for VCT and nevirapine for the prevention of mother to child transmission of HIV in the Kassena-Nankana district of Northern Ghana." Master's thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/8631.
Full textAbstract:
Includes bibliographical references.<br>Mother-to-child-transmission (MTGT) of HIV is one of the tragic consequences of the HIV pandemic, There are antiretrovirals for the prevention of mother-to-child-transmission (PMTCT) and Nevirapine (NVP) is the cheapest, most feasible and highly cost-effective of all and suitable for resource poor settings. Voluntary Counselling and HIV Testing (VCT), known for its effectiveness in behavioral change, is also essential for the prevention of mother-to-child transmission of HIV and for the control of HIV/AIDS. Family Health International and Ghanaian MOH intend to implement a prevention of mother-to-child-transmission in the Kassena-Nankana district using VCT and NVP. The success of the use of VCT and NVP for the prevention of mother-to-child-transmission of HIV depends on new effective and sustainable they are implemented and patronized. The purpose of this study therefore is to assess household willingness to pay for VCT and NVP for the prevention of mother-to-child-transmission of HIV in the Kassena-Nankana district of northern Ghana to provide insights into how the impending programme can be implemented sustainably .
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Nzaumvila, Doudou Kunda. "Reasons given by pregnant women for not returning for their results following voluntary counselling and testing (VCT) for the human immunodeficiency virus at Embhuleni Hospital." Thesis, University of Limpopo (Medunsa Campus), 2010. http://hdl.handle.net/10386/202.
Full textAbstract:
Thesis (M Med.(Family Medicine))--University of Limpopo, 2010.<br>OBJECTIVE: In 2007 36% of the pregnant women tested positive for HIV at Embhuleni Hospital and its satellite clinics. However, only one quarter of those returned to the wellness clinic for their CD4 results so as to begin with Anti-Retrovirus Therapy (ART) if they qualified. The rest would not return to the wellness clinic, and would only present late with opportunistic infections or a subsequent pregnancy. The study aimed at exploring the reasons why women who had been tested for HIV by means of VCT failed to return for their CD4 results, to understand those reasons, to determine what information was given to them before they were tested, to assess the availability of personal support systems (family, friends, etc), and finally to assess the women’s understanding of HIV/AIDS, for which they were tested.
METHODS: A descriptive qualitative study was conducted using the free attitude interview technique for data collection. The Ante-natal care (ANC) clinic register of the Embhuleni Hospital was used to trace patients who had consented for voluntary counselling and testing (VCT), but who had since not returned for their results after 30 days of testing. Those patients were visited at their places of residence by the research team (interviewing nurse and the researcher) to request them to participate in the study. The exploratory question was: “May you tell us why you did not come back for your HIV test results?” “Sicela usichazele kutsi yinindzaba ungasetanga kutewuhlola imiphumela yakho yengati? (SiSwati Version). The interviews were audio recorded and field notes taken. The interviewer sought clarification for unclear issues raised, and gave reflective summaries at the conclusion of each idea under discussion. The interviews continued until there was information saturation. In this study, was reached at respondent number nine. The audio-tapes were transcribed verbatim, followed by translation into English. The emerging themes formed the basis for the write-up.
RESULTS: The following themes emerged:
Communication between health care workers and patients
Poor quality of communication (patients not told to come back)
Knowledge on HIV/AIDS and PMTCT
Patients had poor knowledge of HIV/AIDS and PMTCT
Fear of stigma for HIV/AIDS
The community associated coming back for the results with being HIV positive
Poor patient support
Poor family support system for the patient
Limited patient financial resources
Experience at the health facilities
Lack of patient privacy
Attitude of the health care workers not acceptable to patients
CONCLUSION: The factors that resulted in non-return of the pregnant women to the facility for their results were that the women were not made aware that they were to return for their results; poor quality of communication by the hospital staff; unpleasant experiences by patients at the facility; patients feared community stigmatisation; there was lack of patient support, and the patients had poor knowledge of HIV/AIDS and PMTCT
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Kauffman, Jobriath Scott. "Spatiotemporal Informatics for Sustainable Forest Production Utilizing Forest Inventory and Remotely Sensed Data." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/74974.
Full textAbstract:
The interrelationship between trees and humans is primordial. As pressures on natural resources grow and become more complex this innate connection drives an increased need for improved data and analytical techniques for assessing the status and trends of forests, trees, their products, and their services. Techniques for using readily available data such as the Forest Inventory and Analysis (FIA) database and output from forest disturbance detection algorithms derived from Landsat data, such as Vegetation Change Tracker (VCT), for estimating forest attributes across time from the state and inventory unit level down to the stand and pixel level are presented. Progressively more comprehensive harvest and parcel boundary records are incorporated appropriately. Quantification of attributes, including non-timber forest products and fine-scale age estimates, across the landscape both historically and into the future is emphasized. Spatial information on the distribution of forest resources by age-class provides knowledge of timber volume through time and across the landscape to support forest management for sustained production. In addition to monitoring forest resources in regards to their value as products for human consumption, their measurement facilitates analysis of the relationship of their spatial and temporal abundance to other resources such as water and wildlife.<br>Ph. D.
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Strömbom, Hanna. "Kartläggning av klimatförbättrad betong." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-26057.
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Betong är ett material som vid framtagning av huvudråvaran cementklinker släpper ut stora mängder koldioxid. Enligt nationella klimatmål ska det finnas klimatneutral betong på svenska marknaden till år 2030 och betongen ska nå nettonollutsläpp till år 2045. Ett intensivt utvecklingsarbete pågår i betongbranschen och olika strategier diskuteras för att uppnå lägre klimatpåverkan. Syftet med arbetet är att undersöka hur betongbranschen arbetar mot klimatneutralitet och se hur långt aktörerna kommit i det arbetet. Syftet är även att öka statistiken för klimatförbättrad betong samt se hur den klimatförbättrade betongen står sig mot standarden ftSS 137003:2020 som är under revidering. Arbetet genomfördes genom litteraturstudier, enkätundersökning och dokumentanalys. Litteraturstudien har legat till grund för den teoretiska bakgrunden. Enkätundersökningen som skickades ut till betongtillverkare är primärkällan i studien och har gett en bild av hur branschen ligger till i dagsläget gällande användning av klimatförbättrad betong. Studien kompletterades med en dokumentanalys i form av granskning av EPD:er samt den reviderade standarden. Dokumentanalysen undersökte vilken klimatförbättrad betong som finns redan idag samt hur ändringar i standarden påverkar förutsättningarna för klimatförbättrad betong. Enkätundersökningen och granskningen av EPD:erna visade att viss klimatförbättrad betong redan finns i dagsläget, men att det inte används i så stor utsträckning. Drygt hälften av betongproducenterna hade inte någon klimatförbättrad betong på marknaden i nuläget, men merparten arbetar med att ta fram det och de flesta beräknar att ha det på marknaden inom ett till tre år. Majoriteten av betongtillverkarna var positiva till att all deras betong kommer vara klimatneutral till år 2045. Något som både litteraturstudien och enkätundersökningen fastställde var att samverkan mellan olika aktörer i ett tidigt skede är viktigt för att uppnå klimatneutralitet. För att nå klimatmålen krävs dessutom både att producenterna fortsätter arbeta mot klimatmålen men också mer kunskap och medvetenhet hos konsumenterna.<br>During the production of concrete, a large amount of carbon dioxide is emitted. The Swedish national climate target goal aims for climate-neutral concrete on the Swedish market by 2030 and to further attain a net zero emission by 2045. The concrete production industry is working on strategies to reach these goals and thereby attain a lower climate impact. This study aims to examine how the concrete industry works towards climate neutrality and to see how far they have come in accordance to this goal. A further purpose for this study is to increase the statistics for climate improved concrete and to compare how the climate improved concrete measures up to the revised standard ftSS 137003:2020. The study made use of a literature review, a survey and a document analysis. Through the literature review, information was acquired on theoretical background relating to the interest of study. The data obtained from the survey sent out to concrete producers constituted the primary source. This provided information regarding the current situation in relation to climate improved concrete. As a complement to the survey, the study also did a document analysis of EPDs as well as the revised standard. This tool was used to analyse existing climate improved concrete respectively to examine the revised standard in order to establish how alterations in the standard affects the conditions for climate improved concrete. Based on the results obtained from the survey and analysis of the EPDs, some climate improved concrete are currently available, yet in limited usage. Most of the concrete producers are lacking climate improved concrete on the market, but most of them are working towards this goal with the aim to have such a product on the market within one to three years. The majority of concrete producers are convinced that their concrete will be climate-neutral by the year 2045. Both the literature review and the survey confirmed the importance of collaboration between different actors during an early stage in order to attain climate neutrality in concrete production. To attain the climate goals it requires that concrete producers continue to work towards the climate goals, but moreover, the knowledge and awareness among consumers is also essential.
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Johansson, Gutstav, and Rickard Johansson. "UTTORKNING AV HÅLDÄCKSELEMENT - En studie som jämför uttorkningsmöjligheterna för olika betongblandningar." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-74910.
Full textAbstract:
Håldäcksbjälklag är ett fördelaktigt bjälklagsalternativ på grund av dess många fördelar så som reducerad vikt och snabbt montage. Däremot har bland annat korta byggtider medfört att betongblandningar med lågt vct och hög andel cement efterfrågats av Strängbetongs kunder för att reducera risken för fuktproblematik, då en snabb uttorkning eftersträvas. Med en allt strängare och ambitiösare miljömålsättning har ett behov för att reducera andelen cement uppkommit. Vid en minskad cementmängd ökar således betongens vct vilket leder till en miljövänligare framställning samtidigt som en ekonomisk vinning erhålls. Syftet med undersökningen är därför att undersöka om olika betongblandningar med ett högre vct kan ersätta den nuvarande betongblandningen och samtidigt uppfylla förekommande uttorkningskrav. Detta skulle innebära fördelar för såväl producenterna som för beställarna. Betongen som undersökts i utredningen är av jordfuktig karaktär och är enbart avsedd för håldäckstillverkning. Uttorkningsprocessen som studeras motsvarar uttorkningen från tillverkning fram till montage. Fyra olika betongblandningar fördelade på tolv kuber kommer att undersökas i tre olika klimat och enbart uttorkningsmässiga skillnader mellan kuberna kommer att jämföras. Undersökningen baseras på mätdata som grundar på mätningar utförda av en auktoriserad fuktkonsult via Rådet för byggkompetens, RBK. Betongrecepten i utredningen har framtagits av Cementa. Litteraturstudier används även för att styrka påståenden och underlag som framkommer i rapporten. Resultatet från studien visar att de kuber som förvarats i inomhusklimatet och i klimatrummet har en linjär uttorkningsutveckling, till skillnad från kuberna som är placerade i utomhusklimatet som har en olinjär uttorkningsutveckling. I inomhusklimatet och i klimatrummet har kuberna med högre vct torkat ut mer än betongblandningarna med lägre vct (0,40 och 0,45), däremot är skillnaden i uttorkning minimal i kuberna som har förvarats utomhus. Den fastställda slutsatsen i undersökningen är att mer djupgående och längre mätstudier behövs för att säkerställa hur betonguttorkningen förändras i ett senare skede av uttorkningsprocessen.<br>Hollow-deck joists are an advantageous flooring alternative because of its many advantages such as reduced weight and rapid assembly. However, among other things, short construction times have meant that concrete mixes with low w/c ratio and high proportion of cement have been requested by Strängbetongs customers in order to reduce the risk of moisture problems, when a rapid drying out pursued. With an increasingly stringent and ambitious environmental goal, a need to reduce the proportion of cement has arisen. With a reduced amount of cement, the w/c ratio of the concrete increases, which leads to a more environmentally friendly production, while at the same time an economic gain is obtained. The purpose of the study is therefore to investigate whether different concrete mixes with a higher w/c ratio can replace the current concrete mix and at the same time meet existing drying requirements. This would mean benefits for both the producers and orderers. The concrete that has been investigated in the investigation is of a soil-moist nature and is only intended for hole-deck production. The drying process that is studied corresponds to the dehydration from production to assembly. Four different concrete mixes divided into twelve cubes will be investigated in three different climates and only dehydration differences between the cubes will be compared. The survey is based on measurement data that are based on measurements performed by an authorized moisture consultant at Rådet för byggkompetens, RBK. The concrete recipes in the investigation have been developed by Cementa. Literature studies are also used to substantiate claims and supporting documents that appear in the report. The results from the study show that the cubes stored in the indoor climate and in the climate room have a linear dehydration development, unlike the cubes located in the outdoor climate that has a nonlinear dehydration development. In the indoor climate and in the climate room, the cubes with higher w/c ratio have dried out more than the concrete mixtures with lower w/c ratio (0,40 and 0,45), however, the difference in dehydration is minimal in the cubes that have been stored outdoors. The established conclusion in the study is that more in-depth and longer measurement studies are needed to ensure how concrete dehydration changes at a later stage of the drying process.
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Esack, Abdul Aziz. "Knowledge, attitudes, beliefs and practises (KABP) of adolescents / young adults (15-24 year of age) attending a private general practice, regarding HIV Voluntary Counselling & Testing (VCT)." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/26934.
Full textAbstract:
Background: By 2005 an estimated 5. 5 million South Africans were living with HIV and the peak prevalence of HIV/AIDS occurs in young people aged 15-24 years. In order to develop prevention strategies aimed at young people, it is important to determine risk behaviours for HIV in this age group. As VCT has been shown to impact on risk behaviours, it is important to determine the accessibility of these services to youth. Aim: This study assessed the knowledge, attitudes, beliefs and practises (KABP) of young adults, 15-24 years of age attending a private general practise, regarding risks for HIV and accessibility of HIV Voluntary Counselling and Testing (VCT) services. Methods: This was a cross-sectional study. A self-administered questionnaire was completed by a sample of 100 patients attending a general practice located in Athlone. Results: Thirty-six of respondents were male and 64 were female. The age range was 15 to 24 years, with a mean age of 20.2 years. The demographic profile of the study population was typical of a formal urban settlement in a traditionally coloured area. Sixty four percent of respondents reported current or previous sexually activity, of which 89% reported that they had one sexual partner over the preceding three months and 58%, reported not using a condom at their last sexual encounter. The mean age of sexual debut was 16 years. Most respondents could identify safer sexual practices. While 97% of respondents had heard of HIV, only 33% knew someone who had died of HIV/AIDS. Most respondents knew how HIV was transmitted and 74% felt that they had never put themselves at risk of contracting HIV. Seventy five percent of respondents had heard of VCT, and 60% had considered having a test. Knowledge regarding the location of VCT testing sites, methods of testing and waiting period for results was generally poor. Most respondents had a favourable impression of staff in the clinic/CHC setting and would return to these facilities for HIV VCT. However, 71 % reported that they were prepared to pay for a HIV test. Respondents reported that having an HIV test would have a positive effect on sexual behaviour; however, only a third would disclose their HIV test result. Discussion: Respondents had high levels of awareness of HIV prevention strategies but these did not always translate into the adoption of appropriate behaviours. This disparity between awareness of HIV prevention strategies and actual risk taking sexual behaviour could reflect inadequacies in current HIV education programmes. Knowledge regarding most aspects of HIV VCT was inadequate, but there was a high willingness to test for HIV. Respondents indicated that they were prepared to pay for VCT. VCT could be used to engage with young adults and impact on behaviour changes. Further studies may be useful to illustrate the potential of VCT as a prevention strategy and to promote the allocation of more resources for this purpose.
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Legasion, Michael. "A study on Factors associated with non-disclosure of HIV positive status to sexual partners by adult patients attending the VCT clinic at Nhlangano health centre, Swaziland." Thesis, University of Limpopo (Medunsa Campus), 2010. http://hdl.handle.net/10386/543.
Full textAbstract:
Thesis (M. Med.(Family Medicine))--University of Limpopo (Medunsa Campus), 2010.<br>A study on Factors associated with non-disclosure of HIV positive status to sexual partners by adult patients attending the VCT clinic at Nhlangano health centre, Swaziland.
Aim: To describe the factors associated with non-disclosure of known HIV sero-positive status to sexual partners by adult patients attending the VCT clinic at Nhlangano health center, Swaziland.
Design:- Cross-sectional study using questionnaire administered by a trained research assistant.
Setting:- Nhlangano health center VCT clinic, Nhlangano town in the Shiselweni region, Southern Swaziland.
Study population:- All adult patients above the age of 18 years who had undergone HIV testing, who knew their positive HIV status and had follow up visits at the VCT clinic of Nhlangano health centre, from November 2005 (when the centre started rendering VCT service) till the beginning of the data collection, in September, 2008.
Results:-The vast majority (89.1%) disclosed their positive HIV status to their sexual partners and 94.6% believed that letting their sexual partner/s know about their HIV status was very important. In terms of knowing the HIV status of their partners, 55.4% knew the HIV status of all of their sexual partners and 44.6% knew only the status of the regular partner/s. With regard to condom use, 96.7% believed that using condoms helps them to prevent transmission of HIV and 91.3% expected that letting their partners know about their HIV status would help them use condom
IV
more frequently. Only 53.3% said they would insist on condom use even if their partner is not willing to use.
Conclusion:-
The rate of positive HIV status disclosure to sexual partner found in this study compared to many studies done in other settings is considerably high. This is encouraging especially considering the existing very high prevalence of HIV infection in the country. Despite this though, knowing partner's HIV status was relatively lower. Therefore, people are more likely to share their HIV status with a partner than insist that the partner does the same.
Even though the study was done only amongst patients attending VCT, it is important to note that the majority of the patients had positive attitudes about HIV status disclosure to a partner, and believed in the importance of letting their sexual partner/s know about their HIV status. Patients understood the unethical nature of engaging into sexual intercourse without disclosing their positive HIV status to their partner. It is possible to conclude that factors which contributed to these positive results should be implemented at a larger scale, namely creating awareness, health education, good counseling and follow up of treatment.
Awareness of the importance of condom use in preventing HIV transmission (including the fact that disclosure of HIV status to a partner enhances its better use) was impressively high amongst almost all participants. But it is worrisome that only half of the participants said they would insist on condom use irrespective of their partners’ willingness to use it or not.
V
The variables that were found to be independently associated with disclosure to a partner comparing those who disclosed with those who did not were gender, age, marital status, education, number of sexual partners, and stage of the HIV condition.
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Råssjö, Eva-Britta. "Sexual Behaviour and Sexually Transmitted Infections Among Urban Ugandan Youth – Perceptions, Attitudes and Management." Doctoral thesis, Uppsala University, Department of Women's and Children's Health, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6264.
Full textAbstract:
<p>The aims of this thesis were to expand the knowledge about sexual and reproductive health among urban Ugandan youths, living in a slum, and to evaluate the national flow-chart for management of the abnormal vaginal discharge (AVD) syndrome in adolescent girls. Data collection included individual interviews, focus-group discussions and clinical investigations with tests for chlamydia trachomatis (CT), neisseria gonorrhoea (NG), trichomonas vaginalis (TV), syphilis, and HIV infection. Poverty, peer pressure and gender power imbalance were obstacles to safe sexual practices: to abstain from sex, be faithful or to use condoms. Prevalence among the 199 female and 107 male adolescents for CT, NG, TV, syphilis and HIV was 4.5%, 9.0%, 8.0%, 4.0% and 15.2% for females and 4.7%, 5.7%, 0%, 2.8% and 5.8% for males. The national AVD flow-chart had a sensitivity of 61%, a specificity of 38.5% and a positive predictive value (PPV) of 11.6%. A flow-chart using risk factors, rather than symptoms, implicated a sensitivity/specificity and PPV of 82.6%/47% and 17.3% respectively. Socially disadvantaged females had a high risk to be HIV infected and HIV infection was associated to other STIs. Females were more likely than males to have any of the infections studied. Voluntary counselling and testing (VCT) for HIV was considered as helpful in preventing the spread of HIV. Obstacles for testing were: lack of time and money, fear of stigmatisation and fear that the knowledge of HIV positive status could shorten someone's life. An alternative flow-chart for management of AVD among adolescent girls should be evaluated. Girl's opportunities for education and income generating work should be a priority. VCT services for young people should be made accessible in terms of cost, time and quality of counselling.</p>
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Lê-Bury, Gabrielle. "Infection des macrophages par le VIH-1 : facteurs moléculaires impliqués dans la production virale et dans le développement de bactéries opportunistes The HIV-1 protein Vpr impairs phagosome maturation by controlling microtubule-dependent trafficking Pronounced stealth phenotype and differential pyroptosis induction by invasive Salmonella Typhimurium revealed by coinfection of human macrophages with HIV Role of Solute Carriers in efficient HIV-1 production by human macrophages." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB094.
Full textAbstract:
Le Virus de l'Immunodéficience Humaine de type 1 (VIH-1) infecte les macrophages. Contrairement aux lymphocytes T CD4+, les macrophages résistent aux effets cytotoxiques du virus et représentent un réservoir pour ce pathogène. Dans ces cellules, le virus est produit et stocké dans un compartiment intracellulaire spécifique appelé VCC (Virus-Containing Compartment). Ce compartiment à pH neutre, transitoirement connecté à la membrane plasmique, reste cependant très peu caractérisé. Par ailleurs, le VIH-1 induit une perturbation des fonctions des macrophages, permettant ainsi le développement de bactéries opportunistes, telles que des souches particulières de Salmonella Typhimurium. Nous avons étudié en particulier des souches de Salmonella Typhimurium invasives non typhiques qui se sont développées, chez des patients séropositifs. Les objectifs de ma thèse ont donc été d'étudier, dans les macrophages primaires humains, les facteurs moléculaires impliqués dans la production du VIH-1 et le développement de souches invasives de Salmonella Typhimurium. Dans un premier temps, j'ai contribué à étudier les effets de l'infection par le VIH-1 sur les fonctions des macrophages. Leur fonction majeure est la phagocytose qui est un mécanisme de défense contre les pathogènes permettant leur internalisation et leur dégradation. Il avait déjà été montré au laboratoire que l'étape d'internalisation était en partie inhibée par le facteur de virulence Nef dans les macrophages infectés. Dans ce travail, nous avons montré que l'infection de ces cellules par le VIH-1 inhibe également la maturation des phagosomes, mais via la protéine virale Vpr. Nous avons aussi mis en évidence que le VIH-1 conduit le macrophage dans en état de pré-activation, mais empêche la cellule de répondre à un stimulus ultérieur comme une surinfection bactérienne. Dans un second temps, j'ai participé à l'étude des coinfections entre VIH-1 et les bactéries Salmonella Typhimurium invasives, qui ont émergé avec l'infection par le virus, en comparaison avec des souches de référence. Ce travail nous a permis de montrer que les bactéries, pour leur survie, n'exploitent pas le compartiment viral dans les macrophages co-infectés. J'ai ensuite observé que la souche invasive de Salmonella Typhimurium induit moins de mort cellulaire par pyroptose qu'une souche de référence. J'ai alors déterminé les voies de signalisation en amont de cette mort cellulaire qui est associée à un mécanisme inflammatoire. Ainsi, j'ai mis en évidence que la souche invasive de Salmonella détourne les mécanismes de pyroptose et survit mieux dans les macrophages, ce qui pourrait expliquer la dissémination observée chez les patients. Enfin, j'ai initié l'étude de nouveaux facteurs cellulaires impliqués dans la production virale par les macrophages. À la suite d'une analyse transcriptomique sur des macrophages primaires humains infectés ou non par le VIH-1, nous avons identifié un nombre important de transporteurs membranaires appelés SLC (Solute Carrier) dont l'expression est modulée par l'infection. Après la sélection de candidats, j'ai pu mettre en évidence que certains de ces SLC étaient importants pour la production virale par les macrophages. En conclusion, l'ensemble de ces travaux contribue à définir comment le VIH-1 infecte les macrophages et diminue leurs fonctions d'activation et de clairance, et comment se développent des bactéries opportunistes pathogènes<br>Human Immunodeficiency Virus type 1 (HIV-1) infects macrophages. In contrast to CD4+ T cells, macrophages are resistant to the cytotoxic effects of the virus and represent a reservoir for the pathogen. In these cells, the new virions are produced and stored in a specific intracellular compartment called Virus-Containing Compartment (VCC). This non-acidic compartment, transiently connected to the plasma membrane, remains poorly characterized. In addition, HIV-1 induces an alteration of macrophage function, allowing the development of opportunistic bacteria, such as specific strains of Salmonella Typhimurium. In particular, we studied invasive non-typhoidal Salmonella Typhimurium (iNTS) strains that developed in HIV-positive patients. The aims of my thesis have been to identify the molecular factors involved in the production of HIV-1 in primary human macrophages and to study the development of the invasive strains of Salmonella Typhimurium. First, I participed in studying the effects of HIV-1 infection on macrophage function. Their main role is phagocytosis, which is a defense mechanism enabling internalization and degradation of pathogens. It has previously been shown in the host laboratory that in HIV-1 infected macrophages, the internalization step is partially inhibited by the virulence factor Nef. In this work, we have shown that the infection of these cells by HIV-1 also inhibits the maturation of phagosomes, in this case, via the viral protein Vpr. Further, we have demonstrated that HIV-1 leads to a pre-activation state of the macrophage, while preventing the cell from responding to subsequent stimuli, such as bacterial superinfection. Secondly, I studied the coinfections between HIV-1 and an invasive strain of Salmonella Typhimurium that was compared to reference strains. This work demonstrated that bacteria do not hijack the viral compartment for their survival in co-infected macrophages. Additionally, the invasive strain of Salmonella Typhimurium was observed to induce less cell death by pyroptosis than a reference strain. The signaling pathways upstream of this cell death were determined to be associated with an inflammatory mechanism. Hence, it was demonstrated that the invasive strain of Salmonella hijacks the mechanism of pyroptosis to survive in macrophages. This may explain the dissemination observed in patients. Finally, a study of new cellular factors involved in viral production in macrophages was conducted. Following a transcriptomic analysis of human primary macrophages infected, or not, with HIV-1, we identified a large number of membrane transporters called SLC (Solute Carrier) whose expression was modulated by the infection. After selecting some of the candidates for further study, I have demonstrated that some of these SLCs are important for viral production in macrophages. In conclusion, this work contributes to defining how HIV-1 infects macrophages and disturbs their activation and clearance functions, and how opportunistic pathogenic bacteria develop
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Persson, Herman, and Alexandru Zamfir. "Uttorkning av betong i nyproduktion." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-97204.
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Under de senaste åren har tillverkningsprocessen av betong genomgått en förändring föratt göra materialet och processer mer miljövänliga. Detta är en följd av att betong räknasvara ett av de viktigaste byggnadsmaterialen i världen. En viktig anledning till denomfattande användningen av betong är att betong som material är fuktbeständigt, att detinte möglar och att det är väldigt formbart.Förenta nationerna nämner 17 globala mål vars uppgift är att främja hållbarhet i framtidendär mål nio anger ”Bygga upp en motståndskraftig infrastruktur, verka för eninkluderande och hållbar industrialisering och främja innovation”. Detta faktum måstenaturligtvis tas hänsyn till även vid tillverkningen av betong och dess beståndsdelar.Syftet med det här examensarbetet är att med hjälp av ett stort antal mätpunkter visa påolika styrkor och svagheter inom tre olika typer av prognostiserande beräkningsverktygav torkningstider. Målet med arbetet är att jämföra statistik av praktiska mätningar,utfärdade av Conservator AB, med varandra och med de tre vanligasteberäkningsprogrammen som används för att beräkna uttorkningstider av betong.I de undersökta byggdelarna i arbetet gav TorkaS den högsta noggrannheten och sedanföljt väldigt nära av PPB. Utöver detta uppfyller de förväntningar som borde kunna ställaspå prognostisering av uttorkningstid för betong. Studien har också visat attuttorkningstiden för betong i nyproduktion påverkas mest av uttorkningsklimatet och tjockleken på avjämningsmassan.<br>In the recent years, the manufacturing of concrete has undergone a change to make theprocesses and the material more environmentally friendly. This is accompanied by thefact that concrete is one of the most important building materials in the world. This islargely because concrete as a material is moisture resistant, does not mold and is highlyformable.The United Nations mentions 17 global goals whose mission is to promote sustainabilityin the future whereas the ninth one states that “Build resilient infrastructure, promoteinclusive and sustainable industrialization and foster innovation”. This leads to the factthat it needs to take in consideration the manufacturing of concrete and its components.The purpose of this research is to show strengths and weaknesses in prediction tools forconcretes drying time by comparison with data from many measuring points. Besidesthat, the aim is to compare statistics of practical measurements, which were issued byConservator AB, with each other and with other three most commonly used programs inforecasting the drying time for concrete, i.e. TorkaS, BI-Dry and PPB.From the building sections that were researched, TorkaS gave the highest accuracy inforecasting the drying time and then followed very closely by PPB. In addition, BI-Drydid not meet the expected requirements on some of the building sections. Besides that, thestudy has shown that the drying time of concrete in new production is most influenced bythe drying climate and the thickness of the compound.
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Arguello, Erazo Stalin Efren. "Estrategia de marketing relacional basado en el valor del cliente en el tiempo - VCT y su efecto en el desarrollo de la lealtad de los clientes en los hostales de la ciudad de Riobamba - Ecuador." Doctoral thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/5815.
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Establece el efecto de las estrategias en la lealtad de los clientes de los hostales de la ciudad de Riobamba - Ecuador. De esta manera, contribuye a gestionar de una manera eficiente las relaciones de los clientes internos o externos de los hostales basados en el Marketing relacional a largo plazo.<br>Tesis
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Koskinas, Nikolaos [Verfasser], Rolf-Hermann [Akademischer Betreuer] Ringert, Frauke [Gutachter] Alves, and Albrecht [Gutachter] Neeße. "Die Wirkung des kompetitiven Gastrin-releasing peptide-(GRP-) -Antagonisten RC 3095 auf das Wachstumsverhalten im Modell experimentell induzierter orthotoper Nierenzellkarzinome – Analyse mittels Volumencomputertomographie (VCT) / Nikolaos Koskinas ; Gutachter: Frauke Alves, Albrecht Neeße ; Betreuer: Rolf-Hermann Ringert." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1142001350/34.
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Campacci, Rodrigo Bellotto. "Handover vertical em redes NGN: integrando a sinalização do domínio de comutação de circuitos e o IMS." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-15092008-152814/.
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Este trabalho visa estudar e implementar a integração entre o domínio de comutação de circuitos e o IP Multimedia Subsystem (IMS) para suportar handovers verticais, ou seja, entre redes de acesso distintas, por exemplo, Global System for Mobile communications (GSM) e WiFi, em especial no Serviço Voice Call Continuity (VCC). Entretanto muito pouco é especificado sobre a integração entre os domínios nas normas das diversas entidades de padronização que tratam sobre o assunto. Assim, apresenta-se uma proposta para essa integração, criando-se uma nova entidade funcional para realizá-la, o Call Data Storage Function (CDSF), que interage com os demais módulos do Serviço VCC e garante que algumas informações que devem ser trocadas entre os módulos não sejam perdidas, devido à conversão de protocolos de sinalização na interface entre tais domínios. O CDSF auxilia também no controle da alocação de endereços de referência utilizados no encaminhamento de chamadas de um domínio para o outro. São definidos os protocolos de acesso ao CDSF, bem como os métodos disponíveis. Em sua concepção, recorre-se a uma modelagem modular, que permite futuras melhorias, apenas por troca de módulos. Como estudos de caso para validar a proposta são apresentados cenários de chamadas que utilizam o Serviço VCC, passando pelo CDSF. Por fim, conclui-se que a integração entre os domínios é viável se a proposta deste trabalho for utilizada. Também se demonstra que a separação dos planos de controle dos planos de dados (de usuário) é uma das contribuições fundamentais da arquitetura NGN para o sucesso de suas implementações, como por exemplo o IMS.Além disso, destacam-se as vantagens que o Serviço VCC pode agregar ao IMS, contribuindo para sua adesão em menor prazo pelas operadoras de telecomunicações, dado que esse serviço contribui para a integração de redes, cada vez mais convergentes, agregando mobilidade e continuidade à sua utilização.<br>This work intends to study and implement the integration between the circuit switching domain and the IP Multimedia Subsystem (IMS) to support vertical handovers that are between different access networks, such as Global System for Mobile communications (GSM) and WiFi. Therefore the specifications are incomplete about this topic in standards from the entities who works with this subject. Then, is presented a new proposal for this integration: a new functional entity to realize this integration: the Call Data Storage Function (CDSF), which interacts with other modules of VCC Service and guarantees that some information shared between modules are not lost, due to conversion of signalling protocols in the interface between domains. Besides that, CDSF helps in the control of allocation of reference address that are used to route calls from one domain to another. Access protocols to CDSF are defined and CDSF methods are exposed. The CDSF design uses a modular approach, which allows future improvements, just changing modules. As case studies to validate this work proposal, call scenarios are presented that uses the VCC Service, using CDSF. Finally, it is concluded that the integration between domains is viable if this work proposal is used. It is presented, as well, that the separation between control plans and data plans is one of the main contributions of NGN architecture to the success of its implementations, like IMS. Furthermore, it is exposed the advantages that VCC Service can aggregate to IMS, contributing for more rapidly adoption by telecommunications operators, considering that this service helps the networks integration, adding convergence, mobility and continuity.
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Thomas, George L. "Biogeography-Based Optimization of a Variable Camshaft Timing System." Cleveland State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=csu1419775790.
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Lawrence, Michelle. "Exploring attitudes of University students towards seeking psychological counselling." Thesis, University of the Western Cape, 2009. http://hdl.handle.net/11394/3327.
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Magister Psychologiae - MPsych<br>Student counselling services, typically located within a holistic developmental approach, aim to render comprehensive student services to service users in relation to their psychological, social,educational and spiritual well-being. However, a number of cognitive and affective barriers reportedly reduce the likelihood of young people at universities seeking professional psychological help for personal-emotional problems. Accordingly, the aim of this study, which is located within the Theory of Reasoned Action, was to explore students’ attitudes towards utilising student counselling services, as well as their interpretations of the influence of age,
gender and education on their attitudes and self-rated knowledge regarding seeking
psychological help. The study thereby attempts to provide an understanding of the factors that influence help-seeking behaviours in university students. The research sample consisted of twenty nine students from the Cape Peninsula University of Technology. The data was collected through focus group discussions, which were conducted using an open-ended and participantcentred approach to the discussion. The qualitative approach of the study was informed by the theory of social phenomenology. Data gathered from the focus group discussions was thematically analysed. The results suggest that attitudes have a potentially important influence
on intentions to seek out psychological counselling. Findings show that students feel shame and guilt when they are struggling psychologically and as a result avoid seeking psychological intervention for fear of being negatively stigmatised. The study revealed that education around mental health disorders and the management thereof was crucial in order for them to be demystified and de-stigmatised, and to facilitate openness in the sharing of these problems, and society’s understanding and acceptance of people experiencing psychological disorders. Results also indicate that there is a shift taking place in these attitudes, and suggest ways in which this change can be further facilitated, such as the utilisation of peer helpers who could play a key role in facilitating and reinforcing help seeking behaviour. The outcomes of the study may further contribute to informing universities’ goal to provide accessible, quality and effective development and support services to its students.
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Rasool, Sava Tnar, and Omar Sharif. "Expansion of Sickla treatment plant : A study about the replacement of standard concrete to green concrete." Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-278542.
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Stockholm Vatten has decided to close down the Bromma waste water treatment plantand manage the waste water from Bromma together with the waste water from the formerEolshällsverket to Henriksdal’s waste water treatment plant. Henriksdals wastewater treatment plant will be expanded for higher purification requirements and loads,estimated to be finished until 2040. This entails extensive renovations and additionsto the existing treatment plant in and on Henriksdalsberget, as well as a major expansionof the Sickla plant.The purpose of the study is to investigate an environmentally friendly alternative tothe standard concrete that will be used for the expansion of the Sickla plant. The largestenvironmental villain in concrete is the cement. The aim of this study has beento replace the cement with environmentally friendly additives in the largest possibleamount, thus reducing the negative impact of the cement on the environment.In the present study, a review was made of obtained data with exposure classes, then aliterature study was performed to gain knowledge in the area. With help from experts,two fictitious recipes for each exposure class have been calculated for the standardconcrete and the green concrete. In this way, a careful comparison between the concretetypes was made of the cement’s impact on global warming. Thereafter, a study wascarried out on existing EPDs, which were incorporated into the One Click LCA (2015)software. An LCA in the mentioned software was carried out, which enabled data to becompiled and a comparison of the climate impact between the four different fictitiousrecipes has been done.Compiled and compared data from LCA and analysis of EPDs show that 70% of thestructure with exposure class XD2 gets a 47% reduction in global warming when usinggreen concrete instead of standard concrete. Furthermore, the results show that theremaining 30% of the structure with exposure class XF3/XC4 gets a 20% reductionwhen using green concrete instead of standard concrete. The total reduction in globalwarming when using green concrete instead of standard concrete for the expansion ofSickla treatment plant was calculated to be 40%.<br>Stockholm Vatten har beslutat att lägga ned Bromma reningsverk och leda avloppsvattnetfrån Bromma tillsammans med avloppsvattnet från det forna Eolshällsverkettill Henriksdals reningsverk. Henriksdals reningsverk ska byggas ut för högre reningskravoch belastningar beräknade till år 2040. Detta medför omfattande om- och tillbyggnationeri det befintliga reningsverket i och på Henriksdalsberget samt en storutbyggnad av Sicklaanläggningen.Syftet med detta arbete är att undersöka ett miljövänligare alternativ till standardbetongensom ska användas vid utbyggnaden av Sicklaanläggningen. Då den främsta”miljöboven” i betongen är cementet har målet med denna studie varit att ersätta cementetmed miljövänliga tillsatsmaterial i största möjliga mängd, i syfte att minskacementets negativa inverkan på miljön.I föreliggande arbete har en genomgång utförts på erhållna data med exponeringsklasser,därefter påbörjades en litteraturstudie i syfte att inhämta kunskaper inomområdet. Med hjälp av experter har två fiktiva recept för respektive exponeringsklassräknats fram för standardbetongen och den gröna betongen. Med denna metod genomfördesen noggrann jämförelse mellan de olika recepten avseende cementets inverkanpå den globala uppvärmningen. Därefter undersöktes existerande EPD:er, vilka infogadesin i programvaran One Click LCA (2015). En LCA i den nämnda programvaranutfördes, vilket möjliggjorde att data kunde sammanställas och en jämförelse av klimatpåverkanmellan de fyra olika fiktiva recepten kunde genomföras.Sammanställd och jämförd data från LCA och analys av EPD:er visar att 70% av konstruktionenmed exponeringsklass XD2 får en reducering på 47% på den globala uppvärmningenvid användning av grön betong istället för standardbetong. Vidare visarresultatet att resterande 30% av konstruktionen med exponeringsklass XF3/XC4 fåren reduktion på 20% vid användning av grön betong istället för standardbetong. Dentotala reduktionen på den globala uppvärmningen vid användning av grön betongistället för standardbetong för utbyggnaden av Sickla reningsverk beräknades till 40%.
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Tsatsos, Aristidis. "Die Rechtsprechung der ICSID-Schiedsgerichte." Doctoral thesis, Humboldt-Universität zu Berlin, Juristische Fakultät, 2008. http://dx.doi.org/10.18452/15737.
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Die Beilegung von Investitionsstreitigkeit erfolgt innerhalb des ICSID-Systems durch die nicht ständigen und für jeden Fall neu gebildeten ICSID-Schiedsgerichte. Mit Institutionen zur Sicherung der homogenen Entwicklung der Rechtsprechung wie die EG-Generalanwälte, die EG-Vorabentscheidung, das WTO-„Appellate Body“ oder die einem Berufungsverfahren gleichstehende Verweisung an die Große Kammer des EMRGH ist allerdings das ICSID-System nicht ausgestattet. Vielmehr ist die Möglichkeit einer Berufung innerhalb des ICSID-Systems ausdrücklich ausgeschlossen. In der vorliegenden Arbeit wird die Homogenität der ICSID-Rechtsprechung geprüft, um festzustellen, ob die Rechtsprechung der für jeden Fall neu gebildeten ICSID-Schiedsgerichte derartige Dissonanzen aufweist, die das ICSID-System reformbedürftig machen. Die Prüfung der Homogenität der ICSID-Rechtsprechung bezieht sich auf die Auslegung von gleichen bzw. ähnlichen Bestimmungen völkerrechtlicher Investitionsschutzabkommen sowie des ICSID-Übereinkommens selbst durch die ICSID-Schiedsgerichte und betrifft im einzelnen die folgenden Themen: (a) Definition des Begriffs „Investition“ im Sinne des ICSID-Übereinkommens. (b) Ausdehnung der Reichweite der Meistbegünstigungsklausel auf Verfahrensvorschriften. (c) Zuständigkeit der ICSID-Schiedsgerichte für reine Verletzungen von Investitionsverträgen mittels weiter Streitbeilegungsvorschriften und Regenschirmklauseln. (d) Standard der Enteignungsentschädigung und Unterscheidung zwischen indirekter Enteignung und staatlicher Regulierung. (e) Völkervertraglicher und völkergewohnheitsrechtlicher Notstand. Die Untersuchung kommt zu dem Ergebnis, dass die ICSID-Rechtsprechung an Heterogenität leidet. Dementsprechend bildet der Mangel an Mechanismen zur Sicherung der Homogenität der ICSID-Rechtsprechung ein schwerwiegendes institutionelles Defizit. Es ist daher dringend, dass das ICSID-System unmittelbar reformiert wird, vorzugsweise durch die Schaffung einer ICSID-Berufungsinstanz.<br>The settlement of investment disputes within the ICSID system is carried out by the ICSID arbitral tribunals which are non-permanent judicial bodies. Every separate case is adjudicated by a different tribunal. The ICSID system, however, does not provide for any institutions similar to the EC Advocate Generals, the EC preliminary rulings, the WTO Appellate Body or to the appeal-like process of the referral to the Grand Chamber of the ECHR capable of securing the homogenous development of the case-law. Moreover, the possibility of appeal of an arbitral award is explicitly excluded within the ICSID system. The present thesis examines the homogeneity of the ICSID jurisprudence in order to ascertain whether the case-law of the separate and not standing ICSID panels proves to be so inconsistent that the ICSID system is in need of reform. The study of the homogeneity of the ICSID jurisprudence concerns the interpretation of identical and similar provisions laid down in international investment treaties as well as of the ICSID Convention itself by the ICSID panels. In particular, it deals with the following topics: (a) Definition of the term “investment” pursuant to the ICSID Convention. (b) Extension of the scope of application of the most-favoured-nation clause to procedural provisions. (c) Jurisdiction of ICSID tribunals over mere violations of an investment contract through broad dispute settlement clauses and umbrella clauses. (d) Standard of compensation for expropriation and distinction between indirect expropriation and state regulation. (e) State of necessity under customary and investment treaty law. This study comes to the conclusion that the ICSID jurisprudence suffers from heterogeneity. Thus, the lack of mechanisms able to secure the consistency of the ICSID case-law constitutes a serious institutional deficit. It is, therefore, urgent to reform the ICSID system immediately, preferably by way of establishing an ICSID appellate authority.
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Staffansson, Frida. "En studie om konstruktörer kan minska klimatpåverkan av koldioxid från betong via kravspecifikation." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik och belysningsvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-45269.
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Syfte: Byggindustrin kommer framförallt att påverkas av hållbarhetsutvecklingens framfart. FN har satt hållbarhetsmål presenterade i Agenda 2030 och för att möta dessa mål måste hållbarhet stå i fokus för både yrkesverksamma och intressenter. Betong är ett material som består av ballast, vatten och cement som hårdnar över tiden och används världen över inom byggindustrin. År 2014 uppskattades betongproduktionen stå för hela fem procent av alla antropogena koldioxidutsläpp. Syftet med studien är att undersöka miljöpåverkan från olika betongkvaliteter mätt i koldioxidekvivalenter och använda resultatet för att påvisa om konstruktörer kan göra någon skillnad via sina kravspecifikationer på betong. Metod: En litteraturstudie genomfördes inledningsvis för att säkerställa studiens relevans samt skapa kunskap kring området. LCA och dokumentanalys av EPD möjliggjorde jämförelse av klimatpåverkan och data kunde sammanställas. Resultat: Sammanställd och jämförd data från LCA och dokumentanalys tyder på att konstruktörer kan minska klimatpåverkan genom att föreskriva högre vct och lägre exponeringsklass. Detta möjliggör att en större andel cement kan bytas ut mot tillsatsmaterial. Litteraturstudie tyder på att konstruktörens arbete för att minska klimatpåverkan från betong kan direkt kopplas till mål 13 i Agenda 2030. Mål 13 verkar bland annat för att Sverige inte skall ha några nettoutsläpp av växthusgaser 2045. Konsekvenser: Om konstruktörer i den mån det är möjligt föreskriver högre vct och lägre exponeringsklasser tyder studien på att de kan minska klimatpåverkan från betong. Att föreskriva högre vct och lägre exponeringsklasser är dock inte alltid möjligt med hänsyn till hållfasthet och omgivning. Studien bidrar till att skapa förståelse för hur stora skillnader gällande klimatpåverkan som kan uppstå beroende på betongkvalitet. Begränsningar: Betong erhåller många egenskaper och en uppsjö av parametrar som påverkar dessa egenskaper. Genom att avgränsa studien och bortse från en del parametrar finns risk för orättvisa resultat. Data som används är publicerad data samt data som betongleverantören vill tillge vilket ger ett bristande verklighetsperspektiv. Majoriteten av betongkvaliteterna som analyserades är av en klimatförbättrad betong och har därmed en lägre klimatpåverkan än vad som vanligen används på plats om inte krav finns. På grund av omgivning och andra förhållanden är det inte alltid möjligt för konstruktören att föreskriva högre vct och lägre exponeringsklass. Studiens fokus ligger på klimatpåverkan vilket begränsar möjligheten att koppla resultatet till flera miljömål.<br>Purpose: The construction industry will be fundamentally impacted by sustainable development progression. The United Nations have set goals outlined in the 2030 Agenda for sustainable development. To meet this desired progression, these goals must stand in focus for construction professionals and industry stakeholders. Concrete is a composite material made from aggregates, fluids and cement which hardens over time and is widely used in the construction industry. In 2014 it was estimated to account for more than five percent of all anthropogenic carbon dioxide emissions. The purpose of this study is to investigate the climate impact of various concrete mixtures measured as carbon dioxide equivalents and use this to inform whether construction designers can make a difference through the specifications of concrete mixtures. Method: A literature review was conducted to ensure relevance of the study and establish a knowledge base regarding the subject. LCA and a document analysis of EPDs made it possible to compare climate impacts and data could be compiled. Findings: Data from LCA and document analysis indicates that construction designers can reduce the climate impact through their specifications by subscribing higher w/c ratios and lower exposure classes. This enable a bigger amount of the cement to be traded by additives. A literature study indicates that reducing the climate impact of concrete can directly be related to goal 13 in Agenda 2030. In Sweden, goal 13 is to reach no net emissions of greenhouse gases by 2045. Implications: If construction designers specify higher w/c ratio and lower exposure classes, they can reduce the climate impact from concrete. To specify higher w/c ratio and lower exposure class is not always possible depending on the structural requirements. The study adds to an understanding of the climate impact depending on concrete mixtures. Limitations: Concrete obtains many characteristics which is affected by multiple parameters. Limiting the study data and ignoring some parameters increases the risk of deceptive results. Publicly available concrete certifications and data from concrete professionals is combined in this study. Most of the concrete mixtures selected for analysis are climate friendly types and therefore the results would differ if regular concrete was used. Because of structural requirements and other conditions, it is not always possible for the construction designer to specify higher w/c ratio and lower exposure class. This study focuses on climate impacts which limits the possibility to make connections to multiple sustainable development goals.
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Miranda, Luís José Rato. "PI/VCCM : projecto de intervenção/valorização do castelo de Castelo Melhor." Master's thesis, 2009. http://hdl.handle.net/10400.6/2184.
Full textAbstract:
Castelo Melhor, Lugar e palco do tempo1.
As heranças serão para compreender, viver e salvaguardar.
Na memória serão vincadas as linhas orientadoras mais intensas do hoje, para fazer sentido a compreensão e a acção no futuro, tal como as do passado que determinam o hoje.
A própria interpretação do lugar ou lugares é exercida em qualquer intervenção em Arquitectura de recuperação e valorização.
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Jun-YouPan and 潘均祐. "The Development, Design and Demonstration of Vacuum Cathode Arc Thruster (VCAT)." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/a87z53.
Full text
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Tojal, Joaquim José e. Silva de Carvalho. "Towards a formally verified microkernel using the VCC verifier." Master's thesis, 2010. http://hdl.handle.net/10400.6/3717.
Full textAbstract:
In this thesis we present the design by contract modular approach to formal verification of an industrial real-time microkernel which was not designed with formal verification in mind. The microkernel module targeted is a particular interrupt manager of xLuna Real Time Operating System (RTOS) for embedded systems built by Critical Software S.A. The annotations were verified automatically using the Microsoft Research Verified C Compiler (VCC) tool to reason about concurrency and safety properties of xLuna kernel. The specifications are based in Hoare-style pre- and post-conditions inlined with the real code.
xLuna is a microkernel based on the RTEMS Real-Time Operating System. xLuna
extends RTEMS for run a GNU/Linux Operating System, providing a runtime multitasking
environment for real-time (RTEMS) and non-real-time (Linux) applications.
xLuna runs in a preemptable and concurrent environment. Therefore, we use VCC for reasoning about concurrent executions and some functional and safety properties of
xLuna microkernel. VCC is an automated verifier for concurrent C programs that is being developed by Microsoft Research, Redmond, USA and European Microsoft Innovation Center (EMIC), Aachen, Germany. VCC is being built and used for operating system verification which makes it suitable for our verification work.
Specifications were added to xLuna code following a modular approach to the verification of a specific microkernel module, namely the Interrupt Request (IRQ) module.
The Verified C Compiler (VCC) annotations added cover approximately 80% of the IRQ
manager C code (the remaining 20% of the code are relative to auxiliary functions outside
the scope of our verification work). All the annotations were automatically verified and
proven to be correct.