Dissertations / Theses on the topic 'Strength of unity'

The purpose of this study was to qualitatively examine family relationships in families where one adult member was diagnosed with chronic illness resulting in chronic pain to determine why the crucible, or trial, of chronic illness triggered some families to strengthen while others weakened. The introduction of chronic illness instigates a process of change in family life, yet there is a paucity of research examining families in this situation, specifically when the chronic illness results in chronic pain. Utilizing grounded theory methodology and qualitative data analysis methods, dyadic interviews and periods of observation were conducted with six families across the United States. Questions were focused on family relationships and the impact of adult-onset chronic illness on relationships and family life. Open, axial, and selective coding were conducted during the process of data analysis, illuminating the important role family unity played in helping families remain strong. Findings detail the relationship between family strength and family unity. Adult-onset chronic illness provided a catalyst for families to establish and/or maintain family unity. Five families established or maintained family unity and reported positive changes in family strength, while one family failed to maintain or establish family unity and reported negative changes in family strength leading to separation and eventually divorce. This study has important implications for families facing adult-onset chronic illness and for practitioners serving this population.

Master of Science<br>Department of Architectural Engineering and Construction Science<br>Kimberly Waggle Kramer and Bill Zhang<br>Concrete masonry units are a common method of construction in the world. Since the masonry units can be constructed with ease. Fifty billion water bottles are consumed every year. Lack of waste management and recycling in third world countries has come to the attention of many organizations. The use of plastic bottles in construction materials has been around for the past twenty years, but with little focus on using full plastic bottles in the materials. The Engineers Without Borders student group on the campus at Kansas State University have found a way to utilize the full 500-mL plastic bottle in the creation of concrete walls. The bottles laid horizontally with concrete on both sides and as mortar between the bottles was used. These bottles create large voids in the wall decreasing the compressive strength of the wall. This thesis presents the results of a study conducted to determine the compressive strength of concrete masonry units with plastic bottle cores. The plastic bottles were used to create the center voids in the masonry units. Concrete was placed around the bottles to encase them in the masonry units. The study utilized 500-mL plastic bottles from five different water companies placed inside masonry units of 7.87-inch wide by 8.26-inch high by 15.75-inch long (200-mm wide by 210-mm high by 400-mm long) in size and analyzed the resultant compressive strength. The testing for compressive strength was determined according to the ASTM C140 standard. Results from this study were deemed reasonable due to the testing of concrete cylinders as a control compressive strength. Determination of the compressive strength of the concrete masonry units allows for further study to continue in concrete masonry units with plastic bottle cores to determine if they are viable in third world countries.

This thesis examined the change in skeletal muscle architecture with contractile force production, the relationship of architecture with muscle strength parameters and if muscle tendinous tissue stiffness determines in vivo explosive strength (i.e. rate of torque development, RTD). Muscle and tendinous tissue adaptations to contrasting strength training regimes, and the potential capacity of these tissues to adapt following chronic strength training were also explored. Quadriceps femoris fascicle length (FL) decreased, while the pennation angle (PA) increased in a curvi-linearly manner from rest to maximal voluntary contraction (MVC) torque. Consequently, effective physiological cross-sectional area (effPCSA) during MVC was 27% greater than at rest, although effPCSA measured at rest and during MVC had similar correlations to maximal strength. In the earliest phase of contraction, FL, but not PA, was negatively related (R2=0.187) to voluntary RTD. Neither FL nor PA was related to maximal isometric or dynamic strength. Muscle-tendon unit (MTU) and patellar tendon (PT) stiffness were unrelated to voluntary and evoked RTD. Relative PT stiffness was also unrelated to relative RTD, although relative MTU stiffness was related to voluntary RTD (25-55%MVT, R2≤0.188) and evoked RTD (5-50%MVT, R2≤0.194). MTU stiffness increased after sustained-contraction (SCT, +21%), though not explosive-contraction strength training (ECT). PT stiffness increased similarly after ECT (+20%) and SCT (+16%), yet neither induced tendon hypertrophy. SCT produced modest muscle (+8%) and aponeurosis (+7%) hypertrophy. Chronic strength trained (CST: >3 years) males had substantially greater muscle and aponeurosis size, but similar tendon size as untrained controls (UNT) and short-term (12 weeks) strength trained (STT) individuals. Between these groups, at the highest common force, MTU stiffness was indifferent, while PT stiffness was similarly greater in STT and CST than UNT. These results suggest FL and PA have little influence on muscle strength and tendon stiffness has no influence on RTD. Maximum strength negated any qualitative influence of MTU stiffness on in vivo RTD. Component MTU tissues (muscle-aponeurosis vs. external tendon) adapt differentially depending on the strength training regime. Specifically, free tendon appeared to adapt to high magnitude loading, while loading duration is also an important stimulus for the muscle-aponeurosis. However, chronic strength training was not concordant with greater higher force MTU stiffness, and does not further increase higher force PT stiffness beyond the adaptations that occur after 12 weeks of strength training. Finally, no evidence was found for tendon hypertrophy in response to strength training.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.<br>Includes bibliographical references (leaf 25).<br>Polycarbonates have long been studied for their excellent mechanical toughness. Adding side units to polycarbonate could increase physical properties of the polymer. The role of triptycene in polycarbonate was studied by adding a low concentration of triptycene-containing polymer chains, and using compression testing. The triptycene polycarbonate was a blend created from two separate products. Differential Scanning Calorimetry was used to determine if the samples had phase separated. Thermal degradation of the samples was checked for using Thermogravimetric Analysis. Results indicated that triptycene-containing polycarbonates had higher compressive yield strengths than non-triptycene polycarbonates. The polymers were stronger due to the interlocking mechanism and the steric hindrance of the triptycene units. The design of strengthening polymers by adding triptycene units could prove useful to improve high performing polymers, or to give low molecular weight polymers more stability.<br>by Douglas Fraser.<br>S.B.

The investigation of motor-unit fatigability in reduced-animal models has been dominated by a single fatigue test, one fatigue index, and an emphasis on changes in the magnitude of (usually peak) force. Although the standard fatigue test has been reported to elicit changes in the dynamic phases of an isometric tetanus, this has not been systematically studied in single motor units. Furthermore, changes in the profile of individual tetani during the fatigue test have led some investigators to suggest that other force parameters (i.e., integrated force) or fatigue indices may provide additional information about motor-unit performance during the test. The purposes of this project were to: (1) evaluate the time courses of a variety of force parameters characterizing both the magnitude of force and the dynamic aspects of force during a 4-min fatigue test of functionally isolated cat, tibialis posterior motor units; and (2) determine if motor units could be classified into the conventional motor-unit types based on these new parameters. There was considerable variability in the average time course of the magnitude of force during the fatigue test. The variability within the type FR and F(int) motor-unit groups resulted in several units whose characteristics bordered those which, by definition, separate unit types. The classification of these units depended on the force parameter and fatigue index used to quantify their fatigability. The time course of the magnitude of force also revealed differences in the behavior of potentiating and non-potentiating groups. There were many differences between motor-unit types in terms of dynamic-force parameters before, during and after the fatigue test. Comparison of initial and 2-min values revealed a preferential effect of stimulation on force development in type S and FR units (i.e., increased rate) and on force decay in type F(int) and FF units (i.e., prolonged duration and decreased rate). The time courses of these effects further revealed qualitative differences between different combinations of motor-unit types. Groups of units (or lack thereof) revealed by dynamic-force parameters were compared to conventional motor-unit types by discriminant analysis. The results were not always consistent with conventional types.

Over the last decades, it has been shown that the human neuromuscular system is highly adaptive and can be modified in response to different motor training programs. Depending on the demands of the motor training, the adaptations seem to involve distinct structural and functional changes across the motor cortex, spinal cord and skeletal muscle. The technological development observed in the last years, increased the use of electrophysiological techniques to assess the neuromuscular adaptations to motor training. Nonetheless, the current evidences on the neuromuscular adaptations to different motor training are inconsistent and incomplete, in particular regarding endurance and strength training. This is mainly due to lack of studies based on a rigorous consideration of the limitations of the available techniques. Therefore, the main goal of this dissertation is to give new insights on the adaptations of the neuromuscular system by systematically investigating the changes in its central and peripheral properties in response to endurance and strength training. For this purpose, recent developed techniques for recording and processing electromiographycal (EMG) signals were applied. The first study (STUDY I) investigated if 6 weeks of either endurance or strength training alters the motor unit behavior and if such changes were accompanied by alterations in muscle fiber properties. Intramuscular and multichannel surface EMG recordings were used to investigate the motor unit discharge rates and motor unit conduction velocity (MUCV) of the vastus medialis obliquus and vastus lateralis during submaximal isometric contractions. The results demonstrated that endurance training increased endurance capacity and was accompanied by a decrease of the motor unit discharge rates. In contrast, strength training enhanced maximum force output and was accompanied by an increase of the motor unit discharge rates. By the end of 6 weeks of training, both training programs elicited increases in the motor unit conduction velocity, revealing electrophysiological adaptations of the muscle fiber membrane properties in similar directions. However, in the first 3 weeks of training, when changes in motor unit discharge rates were most marked, changes in MUCV were not observed. These findings reveal different time courses of some of the neural and peripheral adaptations in response to different motor training programs. The observed changes may contribute for distinct neuromuscular fatigue profiles among endurance and strength-trained athletes. Therefore, the aim of the second study (STUDY II) was to investigate the effects of 6 weeks of endurance and a strength training program on acute responses of the muscle fiber membrane properties and discharges rates of low threshold motor units of the vastus medialis obliquus and vastus lateralis muscles during prolonged submaximal isometric contractions. The conduction velocity of the individual motor units was estimated from the averaged multichannel EMG surface potentials by a spike triggered average technique. It was shown that motor unit discharge rate declines over the duration of the sustained contraction and their trend was not significantly affected by training. Conversely, the rate of decline of motor unit conduction velocity during sustained contractions was reduced following six weeks of both endurance and strength training, however a greater reduction is observed following endurance training. These alterations likely contribute to longer times to task failure following endurance training. The third study (STUDY III) intended to clarify the mechanisms involved in the opposite adjustments of the motor unit discharge rate observed in the study I. The results revealed that following 3 weeks of endurance training the excitability in the H-reflex pathway increased but the V-wave amplitude remained unchanged. In contrast, following strength training the V-wave amplitude increased whereas subtle changes were observed in the H-reflex pathway. These results suggest that the elements of the H-reflex pathway are strongly involved in chronic adjustments in response to endurance training, contributing to enhance resistance to fatigue. Conversely, following strength training, it is more likely that increased descending neural drive during MVC and/or modulation in afferents other than Ia afferents contributed to increased motoneuron excitability and maximal voluntary contraction. The present work revealed for the first time that endurance and strength training induces opposite adjustments in the motor unit behavior. Moreover, the distinct adjustments in the spinal cord output, seems to result from changes in different neural mechanisms located at supraspinal and/or spinal level. The neural adjustments following endurance training seems to result from changes at spinal level whereas the adjustments following strength training are likely due to changes at supraspinal level. These adaptations occurred following a short period of training, while no changes in the contractile and electrophysiological properties of the muscle fibers were detectable. Changes at peripheral level occurred only following a longer period of training.

Corrugated paper boxes are the predominant packaging and shipping material and account for the majority of packaging refuse by weight. Wooden pallets are equally predominant in shipping, transportation and warehousing logistics. The interaction between these two components is complex and unexplored leaving industry to compensate with outdated component specific safety factors. Providing a focused exploration of the box and pallet interaction will open the door for holistic design practices that will reduce cost, weight, damage, and safety incidents. This study was separated into four chapters exploring different aspects of the corrugated box to pallet interaction. The first chapter evaluates the support surface provided by a pallet consists of deckboards spaced perpendicular to the length of the pallet. The resulting gaps between deckboards reduce the support to the box. Gaps were limited to 55% of box sidewall length for practical reasons. The effect of gaps was significant and produced a nonlinear reduction in box strength. Small boxes were more susceptible to gaps than larger boxes. Moving the gap closer to the corner increased its effect while increasing the number of gaps did not increase the effect. A modification to the McKee equation was produced that was capable of predicting the loss in strength due to gaps. The equation is novel in that is modifies a widely used equation and is the first such equation capable of handling multiple box sizes. This study also has practical implications for packaging designers who must contend with pallet gap. Chapter 2 explores the relationship between deckboard deflection and box compression strength. Testing found that reducing the stiffness of the deckboard decreases the compression strength of the box by 26.4%. The location of the box relative to the stringer also had varying effects on the box strength. A combination of deckboard stiffness and gaps produced mixed with results with gaps reducing the effect of stiffness. It was observed that lower stiffness deckboards not only deflect but also twist during compression. The torsion is suspected to have a significant influence on compression but further exploration is needed. The third chapter tests the effect of box flap length on box compression strength under various support conditions. Variables included four flap lengths, gaps between deckboards, low stiffness deckboards, column stacking and misaligned stacking. The results show that the box flaps can be reduced by 25% with no significant effect of box strength under any support condition tested. Furthermore, the box flap can be reduced by 50% with less than 10% loss in compression strength under all scenarios. These results have significant sustainability implication as 25% and 50% reduction in box flap reduce material usage by approximately 12% and 24%, respectively. In the fourth and final chapter, the theory of beam-on-elastic foundation is applied to deckboard bending and corrugated boxes. In this model the corrugated box acts and the foundation and the deckboard is the beam. Rotational stiffness, load bridging, and foundation stiffness changes required the development of novel testing solution and model development. The model was capable of predicting the distribution of force along the length sidewall but was not capable of predicting the ultimate strength of the box. The model developed in the study will be applicable in determining potential weakness in the unit load in addition to optimizing those that are over designed. These four chapters represent a considerable contribution of applicable research to a field that relied on outdated safety factors over thirty years. These safety factors often lead to costly over design in an industry where corrugated box and pallets volumes make event the smallest improvements highly beneficial. Furthermore, this research has opened the door for significant additional research that will undoubtedly provided even greater economic and sustainability benefits.<br>Ph. D.

Currently, pallets are designed assuming that the load is distributed evenly on the top of the pallet. When pallets are loaded with packages such as corrugated boxes or returnable plastic containers, due to their physical shape, packages, are not capable of deforming freely with the pallet and a bridging phenomenon occurs. During this load bridging phenomenon, a portion of the vertical forces are redistributed as horizontal forces which causes the redistribution of the vertical compression stresses on the pallet towards the support. As a result, the deflection of the pallet can decrease and the load capacity of the pallet can increase significantly. The second chapter of this paper investigates the effect of package content on pallet deflection. The study concluded that package content did not have a significant effect on pallet deflection within the boundary conditions of the experiment. The third part of this paper considers how a specific pallet characteristic could affect the way a corrugated box performs. Standard box design procedures include adjustments of estimated compression strength for relative humidity, overhang on pallets, vibration, and alignment of boxes. However, there is no adjustment factor for pallet stiffness. The objective of the study described in this thesis is to find an answer for how the compression strength of a box is affected by pallet stiffness and top deckboard twist. The study concluded that the pallet stiffness and top deckboard twist do not have an effect on the compression strength of the box until less than 12% of the area box is supported.<br>Master of Science

During unitized shipment, the components of unit loads are interacting with each other. During floor stacking of unit loads, the load on the top of the pallet causes the top deck of the pallet to bend which creates an uneven top deck surface resulting in uneven, or asymmetrical support of the corrugated boxes. This asymmetrical support could significantly affect the strength of the corrugated boxes, and it depends on the top deck stiffness of the pallet. This study is aimed at investigating how the variations of pallet top deck stiffness and the resulting asymmetric support, affects corrugated box compression strength. Pallet top deck stiffness was determined to have a significant effect on box compression strength. There was a 27-37% increase in box compression strength for boxes supported by high stiffness pallets in comparison to low stiffness pallets. The fact that boxes were weaker on low stiffness pallets could be explained by the uneven pressure distribution between the pallet deck and bottom layer of boxes. Pressure data showed that a higher percentage of total pressure was located under the box sidewalls that were supported on the outside stringers of low stiffness pallets in comparison to high stiffness pallets. This was disproportionately loading one side of the box. Utilizing the effects of pallet top deck stiffness on box compression performance, a unit load cost analysis is presented showing that a stiffer pallet can be used to carry boxes with less board material; hence, it can reduce the total unit load packaging cost.<br>Master of Science<br>Packaged products are primarily shipped as unit loads that consist of packaged products restrained to a platform, commonly a pallet. Paying particular attention to the design of the unit loads' components is necessary to safely ship products while still maintaining low packaging costs and sustainability initiatives. Stacking unit loads is a common practice to effectively use warehouse space, but warehouse stacking causes large amounts of weight for packaging to support. Pallets are not completely rigid and will deform because of this weight. The purpose of the study was to investigate the effect of pallet stiffness on the compression strength of corrugated boxes. Compression tests were completed on boxes supported by pallet designs having different deck stiffnesses. The top deck stiffness of a pallet was determined to have up to a 37% effect on the strength of corrugated boxes. Pressure data recorded between the bottom layer of boxes and the top deck of the pallet showed a larger percentage of pressure was located towards the outside edges of the unit load for boxes carried by a flexible pallet. Effectively, one side of the box was stressed more than the other causing package failure. Utilizing the effects of pallet top deck stiffness on box compression performance, a unit load cost analysis is presented showing that a stiffer pallet can be used to carry boxes with less board material; hence, it can reduce the total unit load packaging cost.

Syfte: Syftet med denna studie är att jämföra fraktur styrkan och frakturmönster hos tre-leds broar utförda i litiumdisilikat när broarna tillverkas genom pressteknik jämfört med frästa tre-leds broar genom CAD/CAM system.Hypotes: Pressteknik är bättre lämpad med avseende till fraktur resistens då fräsning av litiumdisilikat block kan resultera i defekter och spänning i materialet, detta gör materialet mer benäget till chipping/mikroabrasioner på ytan som skulle kunna propagera och på så sätt påverka fraktur resistensen. P-värde sattes till p ≤0.05.Material och metod: 40 3-leds broar tillverkades med pressteknik jämfört med fräst teknik med CAD/CAM system i grupper. Dessa delades in i undergrupper baserat på anatomin. Broarna genomgick en artificiell åldringsprocess som utgjordes av termocykling och förbelastning. Efter den artificiella åldringsprocessen utsattes broarna för belastning fram till fraktur. Den statistiska datan samlades in och analyserades. Även fraktur mönstret analyserades. Resultat: Där fanns ingen signifikant skillnad gällande fraktur styrkan mellan de full anatomiska grupperna. Där fanns inte heller någon signifikant skillnad gällande fraktur styrkan mellan underkonstruktion grupperna. Hypotesen falsifieras därför.Slutsats: Där fanns ingen signifikant skillnad gällande hur mycket belastning det krävs för att frakturera broarna som tillverkats genom pressteknik jämfört med broarna tillverkade med hjälp av CAD/CAM teknik. Där finns ett tydligt mönster gällande fraktur mönstret men en slutsats kan inte dras med tanke på antalet broar som använts.<br>Aim: The aim of this study was to compare fracture load and fracture mode of three-unit fixed partial dentures, made in lithium disilicate when the FDPs are made with pressing technique versus milled with a CAD/CAM system.Hypothesis: Pressing technique is better suited with regards to fracture load since milling of lithium disilicate blocks can result in defects and tension build up in the material, leaving the material more prone to chipping/micro-abrasions on the surface that could propagate and thus affecting the fracture load. P-value set to p ≤0.05.Material and methods: 40 FDPs where manufactured with pressing technique versus milled with a CAD/CAM system in each group. Furthermore, each group where subdivided depending on the anatomy. The FDPs thereafter underwent an artificial ageing process consisting of thermocycling and preloading. After the artificial aging process the FDPs were subjected to load to fracture, where the statistical data was collected and analyzed. Also, the fracture mode was observed and analyzed.Results: There was no significant difference regarding the fracture strength between the full anatomy groups. There was also no significant difference regarding the fracture strength between the core-design groups. The hypothesis was therefore rejected.Conclusion: There is no significant difference with regards to how much load is required to fracture FDPs made through pressing technique compared to FDPs made through the use of CAD/CAM technique. There is a clear pattern regarding the fracture patterns, however a conclusion can’t be drawn considering the sample size.

A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry. Objectives: To date, the literature has shown that a 10 second curing time is necessary to consistently achieve effective shear bond strengths (SBS) of greater than 10 MPa. Recently, several manufacturers have developed high power curing lights that claim only a 6 second cure time is needed. The purpose of this study was to evaluate the shear bond strength of orthodontic brackets when using two new high power LED curing lights after a 6 and 12 second light curing time. Methods: 120 extracted premolars were divided into 6 groups (n=20). Metallic brackets were bonded using Transbond XT (3M-Unitek) and cured for 6 or 12 seconds using two high power LED curing lights (Ortholux Luminous LED, 3M-Unitek; OrthoValo, Ultradent) and one control LED unit (Ortholux LED, 3M-Unitek). The samples were stored in distilled water for 24 hours at 37°C, thermocycled and then debonded using an Instron Universal Testing Machine at a crosshead speed of 5mm/min. Bond failure was evaluated under optical microscopy using a modified adhesive remnant index (ARI). Results: All sample groups produced mean SBS higher than 10MPa. Significant reductions in SBS were observed with the Ortholux LED when the curing time was reduced from 12 to 6 seconds. The OrthoValo had significantly higher SBS than the Ortholux LED and the Ortholux Luminous LED at 6 seconds. At 12 seconds, OrthoValo SBS were significantly higher than Ortholux LED only. A higher frequency of enamel damage occurred in the OrthoValo group (28.2%) compared to the Ortholux LED (12.5%) and Ortholux Luminous LED (7.5%). No significant correlation was found between ARI score and SBS. Conclusions: Higher SBS were obtained in the OrthoValo group. This coincided with a higher frequency of enamel damage.

This study investigates the through-thickness behaviour of carbon/epoxy laminates. A through-thickness compression test regime was conducted utilising three specimen designs, which are waisted, hollow cylindrical and cubic specimens. An assessment and comparison of each specimen is given regarding their advantages and disadvantages in characterising the through-thickness response of [+45/-45/90/0]s quasi-isotropic AS4/8552 carbon/epoxy laminates. A finite element (FE) study of the three specimens is presented which results in specimen geometries that provided a macroscopically uniform stress response throughout the gauge length whilst also minimising other features such as stress concentrations. Further to the final geometries being presented, the method of manufacture for the laminate and machining processes for each of the specimens is given. A mesoscopic FE study is presented relating to the free-edge effects induced by through-thickness loading in quasi-isotropic laminates. The results presented show that free-edge effects will be present in the test specimens and will have a larger overall impact on the hollow cylindrical specimen. The free-edge effects also increase the stress concentrations present in the corners of the waisted and cubic specimens. Characteristic stress strain curves are presented for each specimen with strain data taken from post yield strain gauges attached to the specimens. The extracted initial Young's modulus Ez and Poisson's ratios vzx and vzy show a small variation between specimens. The strength values for the three specimens vary greatly with the waisted specimen being the strongest and cylindrical specimen the weakest, indicating that the chosen specimen geometry dominates failure. The experimental data will be used for test case 12 in the Second World Wide Failure Exercise (WWFE-II). A study is presented to predict the effective elastic properties of Z-pinned laminates. The materials under consideration are UD and [0/90]s cross-ply AS4/3501-6 carbon/epoxy laminates. Estimates on the effective properties are provided by two FE approaches and two analytical bounding approaches; namely Voigt and Reuss bounds and Walpole's bounding theory. The two FE approaches are based on extreme assumptions about the in-plane fibre volume fraction in the presence of Z-pins and provide a tight range of values in which the real result should lie. Furthermore, whilst the bounding methods are simple and in the case of Young's moduli produce very wide bounds the selection of the suitable bound result can lead to a good estimate in comparison with the FE data. Typically the best bounding method result for each elastic property is within 10% of the FE predictions.

In this thesis great emphasis has been placed on vastus lateralis (VL) muscle-tendon unit (MTU) structure, behaviour/movement and adaptation. Of particular interest was how external loading and movement speed influence these variables. In the first study (Chapter 3) we developed a new methodology by which electromyography (EMG) could be normalised during large range of motion knee extensions. This methodology was then used as part of a larger study, which investigated how external loading influenced the interaction of muscle and tendon (MTU behaviour) during stretch shortening cycle isoinertial knee extensions, and how muscle activity and intrinsic tendon force (Ft) influenced MTU behaviour (Chapter 4). In this study it was observed that as external loading increased the tendon strain decreased despite muscle activity and Ft increasing. It was concluded that the rapid rate of Ft development (RFDt) and speed of movement resulted in an increase in tendon stiffness that was neglected additional strain that is normally associated with increased load/force. We then investigated how external loading influenced MTU behaviour during parallel depth jump squats (JS-P), which is a more complex but also more commonly performed movement (Chapter 5). Our findings in this study contrasted those of our previous study in that we observed tendon strain increased as external loading increased. Further investigation revealed that while peak Ft increased and movement velocity decreased with increased loading intensity, the RFDt through the tendon did not significantly increase with external loading. In addition, when comparing the results from this study to those of the previous study it was found that the peak RFDt observed during heavy squat jumps was a fraction of the value observed during heavy leg extensions. These results led us to the conclusion that the RFDt that is the primary determinate of MTU behaviour and the influence of loading on MTU behaviour varies between tasks. In our next study we investigated how speed of movement influences MTU behaviour during parallel depth squatting-type movements (Chapter 6). In this study it was observed that the influence of speed of movement had on MTU behaviour differed between the eccentric and concentric phases. Specifically, it was observed that during initial tendon loading the tendon went through less strain when the movement was performed at faster speeds, however, late in the movement tendon strain increased with increased movement speed. Further investigation revealed that during initial tendon loading RFDt significantly increased with increasing movement speeds, which resulted in the viscoelastic properties of the tendon to predominate the movement. However, late in the movement when relative differences in RFDt were small the tendon behaved as a predominately elastic structure. The results from this study along with the studies prior highlighted that changing either the external load or the speed at which the load it lifted can vastly influence of the VL-MTU behaviour. In the final study of this thesis we compared the training specific structural and mechanical adaptations to slow-speed, high-load (SHL) squat training to determine how this might differ to relatively fast-speed, light-load (FLL) jump squat training (Chapter 7). In this study we observed that both groups significantly increased their strength, the cross sectional area of their quadriceps muscles, and the fascicle length of their VL. However, only subjects in the SHL group were able to increase the stiffness of their quadriceps tendon and only subjects in the FLL group increased their VL fascicle angle. It is believed that the observed training specific adaptations resulted from previously observed differences in MTU behaviour, intrinsic forces, and muscle activity observed in the previous studies. Because of this it is concluded that intentional manipulation of external load and speed of movement are viable ways to target specific muscular and tendinous adaptations. The results of this thesis has potential practical applications for designing training programs for athletes and sets the stage for further investigation into how these variables can be manipulated for prevention and rehabilitation of musculotendinous injuries.

INTRODUÇÂO: A sepse representa aproximadamente 25% dos pacientes internados em Unidades de Terapia Intensiva (UTI) e com taxas de mortalidade de 20 a 40%. Além disso, os pacientes sépticos podem apresentar aguda e tardiamente disfunções de órgãos e alterações da musculatura esquelética comprometendo a recuperação na UTI e, posteriormente, a sua saúde relacionada à qualidade de vida. Atualmente, a ultrassonografia tem demonstrado ser uma ferramenta capaz de avaliar a degradação da musculatura esquelética em pacientes críticos. Em pacientes sépticos não se estudou a relação de degradação muscular com testes clínicos de força muscular e aferições bioquímicas. OBJETIVOS: Quantificar a área de secção transversa do reto femoral e a força muscular a beira leito em pacientes que desenvolveram sepse grave e choque séptico. Avaliar associação entre a área de secção transversa do reto femoral e a força muscular em pacientes sépticos. MÉTODOS: Coorte prospectiva que avaliou 37 pacientes na UTI com sepse grave ou choque séptico. A medida da área de secção transversa do reto femoral foi realizada através da ultrassonografia no dia seguinte ao início da sepse e acompanhada durante a internação. Os pacientes foram submetidos a testes clínicos de força muscular (escala do Medical Research Council e a força de preensão palmar) à medida que pudessem compreender comandos verbais. Amostras de sangue foram coletadas para análise de enzimas e hormônio após a admissão no estudo e durante a internação. RESULTADOS: Houve um declínio da área de secção transversa do reto femoral de 5,1 (4,4-5,9)cm2 no 2° dia de UTI para 4,4 (3,6-5,0)cm2 e 4,3 (3,7-5,0)cm2 na alta da UTI e na alta hospitalar, respectivamente (p<0,05). Por outro lado, os testes clínicos de força apresentaram um aumento na escala do Medical Research Council de 48,0 (36,0-56,0) pontos para 60,0 (48,0-60,0) pontos na alta da UTI, este aumento foi mantido até a alta hospitalar em 60,0 (52,0-60,0) pontos (p < 0,05). Em relação à força de preenssão palmar os pacientes apresentavam média de 42,1±21,9 % do predito no 1° dia de avaliação e este valor aumentou para 65,9±20,3 % do predito no dia da alta hospitalar (p < 0,05). Houve uma associação da área de secção transversa do reto femoral e das avaliações clínicas de força muscular durante a permanência na UTI. Aumentos no escore de lesão orgânica (SOFA) no 3° dia e ser do sexo masculino apresentaram-se como fatores independentes para a degradação muscular, assim como, o SOFA do 3° dia com a fraqueza muscular. CONCLUSÃO: O estudo demonstrou que a sepse pode levar a uma degradação muscular em apenas alguns dias de UTI, associada há uma recuperação incompleta da força muscular ao longo da internação. Além disso, testes clínicos de força muscular se associaram com a degradação muscular durante a internação hospitalar<br>INTRODUCTION: Sepsis represents 25% of patients in the intensive care unit (ICU) with mortality rate of 20 to 40%. In addition, septic patients can present early or lately organ dysfunction and skeletal muscles alterations that reduce patient recovery and compromises health-related to quality of life. Currently, ultrasound has been shown to be a tool capable of evaluating skeletal muscle degradation in critical patients. There are no studies in septic patients about the relation of muscle degradation with clinical tests and blood biochemistry analysis. OBJECTIVES: To quantify the rectus femoris cross-sectional area and muscle strength at the bedside in patients who developed severe sepsis and septic shock. To assess the association between the rectus femoris cross-sectional area and muscle strength in septic patients. METHODS: Prospective cohort who evaluated 37 patients in the intensive care unit with severe sepsis or septic shock. The measurement of rectus femoris cross-sectional area was performed by ultrasonography on the day after the onset of sepsis and followed up during hospitalization. Patients underwent clinical tests of muscle strength (Medical Research Council scale and handgrip strength) as they could understand verbal commands. Blood samples were collected for enzyme and hormone analysis after admission to the study and during hospitalization. RESULTS: There was a decline in rectus femoris cross-sectional area from 5.1 (4.4-5.9) cm2 on the 2nd day of ICU to 4.4 (3.6-5.0) cm2 and 4.3 (3.7-5.0) cm2 at ICU discharge and at hospital discharge, respectively (p < 0.05). In contrast, strength tests showed an increase in the scale of the Medical Research Council from 48.0 (36.0-56.0) to 60.0 (48.0-60.0) points in ICU discharge, this increase was maintained until hospital discharge reaching 60.0 (52.0-60.0) points (p < 0.05). In relation to the handgrip strength, patients presented a mean of 42.1 ± 21.9% of predicted on the 1st day of evaluation and this value increased to 65.9 ± 20.3% of predicted on the day of hospital discharge ( p < 0.05). There was an association between the rectus femoris cross-sectional area and clinical assessments of muscle strength during ICU stay. Increases in the organic lesion score (SOFA) on the 3rd day and being male presented as independent factors for muscle degradation, as well as the SOFA of the 3rd day with muscle weakness. CONCLUSION: The study demonstrated that sepsis can lead to muscle degradation in only a few days of ICU, associated with an incomplete recovery of muscle strength throughout hospitalization. In addition, clinical trials of muscle strength were associated with muscle degradation during hospital stay

The ability to change direction rapidly and efficiently is critical to team-sport performance, including Australian football (AF), where a player’s capacity to rapidly decelerate, move laterally and re-accelerate is critical when evading opponents, tackling, or reacting to the unpredictable bounce of the ball or movement of another player. The biomechanical loading requirements of change of direction (COD) movement are angle and velocity dependant. Cumulative COD movement can impart high levels of neuromuscular and metabolic fatigue which can adversely affect the efficiency of subsequent movement efforts. Despite widespread use of microtechnology devices (the vast majority containing a global navigation satellite system receiver and inertial sensors) in elite level team-sport, a valid solution to automatically detect COD events and quantify the associated biomechanical load of these movements on-field remains absent. This project served to develop an algorithm that can automatically detect COD events, quantify the angle of the COD event and quantify the associated biomechanical load of each COD event. Study 1 and 2 were primarily focused on assessing the validity and reliability of the detection and angle quantification portions of the algorithm in both structured (Study 1) and unstructured (Study 2) movement environments, whilst Study 3 introduced a COD biomechanical load quantification technique to profile the COD demands of match play and a variety of match simulation training drills, provide comparisons between playing positions, and assess any similarities or differences with existing proprietary locomotive metrics. Whilst both COD event detection and angle quantification were highly accurate in a structured environment (Study 1), the accuracy of the angle quantification was severely reduced during unstructured, match-simulation training (Study 2). Utilising the event detection and biomechanical load quantification portions of the algorithm together, without angle quantification, the COD demands of match play were significantly lower than three different training drill types when expressed relative to time, whilst several positional differences were also present in COD demands across an entire season (Study 3). Study one assessed the validity and reliability of a novel algorithm to automatically detect and calculate COD angle for pre-determined COD events ranging from 45° to 180° in both left and right directions. Five recreationally active males ran five consecutive predetermined COD trials each, at four different angles (45°, 90°, 135° and 180°) in each direction wearing a commercially available microtechnology unit (Optimeye S5, Catapult Innovations). Raw inertial sensor data were extracted, processed using our novel algorithm to calculate COD angle, and compared against a high-speed video (remotely piloted, position-locked drone aircraft) criterion measure. Concurrent validity was present for the following angles; (Left: 135°= 136.3 ± 2.1° and Right: 45°= 46.3 ± 1.6°; 135°= 133.4 ± 2.0°; 180°= 179.2 ± 5.9°) with a mild bias (< 5° or 6%) present for remaining angles; (Left: 45°= 43.8 ± 2.0°; 90°= 88.1 ± 2.0°; 180°= 181.8 ± 2.5° and Right: 90°= 91.9 ± 2.2°). All measurement of angles demonstrated good reliability (CV < 5%), whilst greater mean bias (3.6 ± 5.1°), weaker limits of agreement and reduced precision were evident for 180° trials when compared with all other angles (p < 0.001). These results confirm the high-level of accuracy and reliability of our novel algorithm to detect COD events and quantify COD angle during pre-determined COD trials and further advocates the use of inertial sensors to quantify sports-specific movement patterns. Study two assessed the validity and reliability of both the original COD algorithm (Study 1) as well as an enhanced version to automatically detect COD events during Australian football match simulation training. The accuracy of detected COD angles was assessed from both absolute angle and discrete categorisation through multi-rater video observation as the criterion measure. Twenty-five elite, professional male Australian footballers’ completed a match simulation training drill on a modified playing area (140 m x 70 m) where video footage was recorded from multiple angles (rear and perpendicular to play) and a 3-minute portion of the drill was synchronised and chosen for the manual coding process to be performed by three different expert raters. Each rater was required to manually note the time-point that each player performed a COD event, whilst also required to document the direction (i.e. left or right), a precise COD angle (between 30° and 180°) and to subsequently categorise the COD angle into pre-determined angle zones (Zone 1: 30-60°, Zone 2: 61-90°, Zone 3: 91-120°, Zone 4: 121-150°, Zone 5: 151-180°). Sensitivity of the enhanced algorithm (95.1%) in correctly detecting COD events was greater than the original version of the algorithm (50.9%), however, the enhanced algorithm significantly underestimated mean COD angle (absolute) (p < 0.01, d = 1.07 – 1.13) and mean COD angle zone (discrete) (p < 0.01, d = 0.84 – 0.91) when compared against each of the expert raters, whom demonstrated excellent inter-rater reliability for both COD angle (ICC: 0.997, p < 0.001) and COD angle zone allocation (ICC: 0.993, p < 0.001). The COD event detection capacity of the enhanced algorithm remained high in unstructured, chaotic, match simulation training, whilst the COD angle detection accuracy was poor, likely due to the spontaneous nature of the training drill and individual biomechanical variation to pre-determined versus reactive COD movement. The accuracy of the COD event detection portion of the algorithm provides an opportunity to further integrate sensor signal outputs in a different manner to obtain and track mechanical loading requirements of on-field COD movement during team-sport activity. Study three provided a method to quantify the mechanical load associated with each COD event which was subsequently used to profile the COD demands of 3 different training drills for comparison against match play data. Positional differences in COD demands were also assessed across the season, whilst our newly developed COD metrics were compared against existing proprietary metrics to determine their novelty. Forty-five elite Australian footballers’ provided player movement data via a commercially available microtechnology unit (Optimeye S5, Catapult Innovations) for both training and match play across the course of an entire AFL premiership season. Three different types of match simulation style training drills were compared to assess the effect that field size and player density has on COD frequency and load (and other proprietary movement metrics). Each of these drill types were also compared against match play to ascertain whether these drills meet the COD (and other movement) requirements of match play, where match play positional COD demands were also assessed across the course of a season. The relative COD demands (COD frequency and load relative to time) of each training drill type (Small-Sided Games (SSG), Mini Footy, Team Training) were greater than match play (p < 0.01), whilst the COD demands of each drill were proportional to field size and player density of each specific drill where SSG demonstrated the greatest demand for COD frequency and load, followed by Mini Footy, then Team Training. During match play, the relative COD requirements (CODAlg) were greater for inside midfielders when compared against mobile defenders (p = 0.001, d = 0.90, moderate) and tall forwards (p = 0.031, d = 1.04, moderate). Additionally, outside midfielders (p = 0.048, d = 0.54, small) and mobile forwards (p = 0.027, d = 1.07, moderate) accumulated significantly more COD events than mobile defenders. Inside midfielders recorded a significantly higher rate of COD load (CODLoadAlg) than mobile defenders (p < 0.001, d = 1.33, large), rucks (p = 0.026, d = 1.25, large) and mobile forwards (p = 0.047, d = 0.03, trivial). Both outside midfielders (p = 0.008, d = 0.91, moderate) and mobile forwards (p = 0.003, d = 1.39, large) recorded a significantly higher rate of CODLoadAlg than mobile defenders. CODAlg and CODLoadAlg were largely correlated (p < 0.01) with relative IMA-COD during each training drill as well as match play. Almost all relative physical output measures (except IMA-Decel) decreased during each subsequent period (quarter and half) of match play. The COD demands of three different types of match simulation training drills all exceeded the demands of match play, however, whilst at a lower rate, players are required to sustain these COD demands for a far greater duration (i.e. across an entire match where physical output markedly changes), when compared with training drills. Differences in COD demands present across positions may provide unique information that enables individualised, position-specific training prescription to more closely align with the evident differences during match play. These novel COD movement metrics may provide an alternative insight into the movement demands of team-sports and ultimately enhance load monitoring practice to optimise performance and reduce injury risk. These three experimental studies as a collective provide a valid solution to detecting COD events and quantifying the associated mechanical load of COD movement during on-field team-sport activity; as well as provides a unique insight into the COD prevalence and mechanical load requirements of AF training and match play. The findings of this thesis may extend beyond elite AF and have the potential to influence future practice in various other team-sport environments.

This Diploma thesis deals with design of the drive and frame of the face and side picking unit of the Multitower storage system, and deals with their strength analysis. The first part of the thesis is the research part and deals with the picking unit´s conception, power options, drive solutions, carriage and safety elements. The thesis also deals with the solution of the wheel´s passive resistance, drive and brakes of both picking units. There are designed appropriate solutions on the basis of the results. The final part of the thesis contains the description of the picking unit structure and the strength analysis.

The thesis summarizes the methods used to test and evaluate the characteristics of vertical masonry structures and further shows the evaluation procedure according to ČSN ISO 13 822. In the second part of this work there is a practical example of brick building assess-ment process, including determining the strength of the walls and the conversion of select-ed critical elements of the existing structure – window pier and wooden beamed ceiling.

This thesis examined the thermoregulatory and neuromuscular responses to passive heating in 42 °C hot water. The data suggest that hot-water immersion at 42 °C is an efficient, safe and tolerable method for passive heating therapy. Moreover, a single session of hot-water immersion can increase rapid force production and improve muscle contractile function. Findings from this thesis indicate that passive heating via hot baths may improve physical function in the older and patient populations and assist healthy people during sports injury recovery.

Introdução. O imobilismo durante a internação hospitalar pode levar a diversos efeitos deletérios, sendo a fraqueza muscular uma das principais alterações encontradas(1). Estudos mostram que pacientes críticos podem ter uma diminuição na força e na massa muscular com variações de 1 a 1,5% por dia e até 50% do total da massa muscular em duas semanas(2). Embora exista o conhecimento da pré-disposição a disfunções musculoesqueléticas durante a internação na Unidade de Terapia Intensiva (UTI), poucas são as evidências claras e consistentes que analisem o quanto que a força e a ativação muscular estão relacionadas com a perda funcional. Objetivo. Analisar a associação entre alterações musculares, perda funcional e variáveis clínicas de pacientes críticos após internação na Unidade de Terapia Intensiva através da avaliação da força, função e atividade muscular no momento da alta da UTI. Desenho do estudo. Estudo observacional, longitudinal. Métodos. O estudo incluiu pacientes de Unidades de terapia intensiva do Hospital das Clínicas de São Paulo e foi aprovado pelo Comitê de Ética e Pesquisa CAAE: 45060215.3.3001.0068. Foram incluídos no estudo pacientes com idade igual ou maior de 18 anos, internados diretamente na UTI desse hospital, não vindo de outros serviços, sem déficits neurológicos, sem contraindicações para a execução dos testes propostos e sem contraindicação para mobilização durante a estadia na UTI. Foram excluídos pacientes com menos de 4 dias de internação, que apresentarem edema no momento da avaliação de eletromiografia ou que durante a internação evoluíssem com alterações neurológicas. No momento da admissão foram colocados aceleromêtros nos indivíduos para o controle do nível de atividade física. No momento da alta da UTI foi realizada uma avaliação para a análise de força a ativação muscular através da Força de preensão palmar (FPP), medida pela dinamometria, e a Eletromiografia (EMG). Também foram realizados testes de campo, entre eles estão o teste de sentar e levantar de 30 segundos, teste de marcha estacionária de 2 minutos e Timed up and Go (TUG). Resultados. Foram analisados 107 pacientes com 53±15 anos, 51% do sexo feminino, 26% estiveram sob VMI, 20% apresentaram algum quadro séptico, com um tempo de internação na UTI de 10±8. Na análise de FPP obtivemos um valor médio de 20 kgf ±9, já para ativação muscular verificamos uma porcentagem de ativação de 30%±19 para o músculo vasto lateral. Na análise de associação verificamos valores significativos para ambos testes em relação a perda funcional na UTI, sendo que a diminuição da FPP aumentou 8% a chance de perda funcional (OD=1,084, IC 95% 1,025-1,147) e a menor ativação do vasto lateral 13% (OD=1,131, IC 95% 1,027 - 1,246). Os testes de campo mostraram associação com a FPP: o teste de sentar e levantar apresentou um R ajustado de 0,325 e um p < 0,001, já o teste de marcha estacionária teve um R ajustado 0,208 e p = 0,03. A FPP também teve associação com as variáveis clínicas: idade (R ajustado 0,22 e p = 0,031) e sepse (R ajustado 0,242 e p = 0,016). Já o músculo vasto lateral teve associação com a porcentagem de tempo em inatividade (R ajustado 0,235 e p = 0,01) e uso de VMI (R ajustado 0,2 e p = 0,03). Conclusão. Nossos resultados mostraram que a FPP e a ativação do músculo vasto lateral tem associação com o declínio funcional. Além disso a força muscular apresentou associação com o teste de sentar e levantar e de marcha estacionária. Percebemos que esses achados apresentaram também associação de variáveis como VMI, idade, sepse e porcentagem de tempo em inatividade. Portanto a avaliação dessas variáveis provou ser importante para auxiliar na proteção da perda funcional em pacientes de UTI<br>Introduction. Immobilism during hospitalization can lead to several deleterious effects, with muscle weakness being one of the main alterations found (1). Studies have shown that critical patients may have a decrease in strength and muscle mass ranging from 1 to 1.5% per day and up to 50% of total muscle mass in two weeks (2). Although there is knowledge of the pre-disposition to musculoskeletal disorders during hospitalization in the Intensive Care Unit (ICU), there are few clear and consistent evidences that analyze how much muscle strength and activation are related to functional loss. Goal. To analyze the association between muscle changes, functional loss and clinical variables of critically ill patients after admission to the Intensive Care Unit through the evaluation of muscle strength, function and activity at discharge. Study design. Observational, longitudinal study. Methods. The study included patients from Intensive Care Units of the Hospital das Clínicas of São Paulo and was approved by the Ethics and Research Committee CAAE: 45060215.3.3001.0068. The study included patients aged 18 years and over, admitted directly to the ICU of this hospital, not coming from other services, without neurological deficits, without contraindications to the proposed tests and without contraindication to mobilization during the ICU stay. Patients with less than 4 days of hospitalization were excluded, who presented edema at the time of electromyography evaluation or who, during hospitalization, progressed with neurological changes. At the time of admission, accelerometers were placed in the individuals to control the level of physical activity. At the time of ICU discharge, an evaluation was performed for the analysis of muscle activation through FPP, measured by dynamometry, and EMG. Field tests were also performed, among which are the sit-and-stand test of 30 seconds, 2-minute stationary gait test and 3-meter lift and walk test. Results. A total of 107 patients, 53 ± 15 years old, 51% female, 26% were under IMV, 20% presented septic, with an ICU length of 10 ± 8. In the FPP analysis we obtained a mean value of 20 kgf ± 9, whereas for muscle activation we verified a percentage of activation of 30% ± 19 for the vastus lateralis muscle. In the analysis of association, we found significant values for both tests in relation to the functional loss in the ICU. The FPP increased the chance of functional loss (OD = 1,084, 95% CI 1,025-1,147) and the vastus lateral activation 13% (OD = 1.131, 95% CI 1.027-1.246). Field tests showed association with FPP: the sit-up test had an adjusted R of 0.325 and a p < 0.001, while the stationary gait test had an adjusted R of 0.208 and p = 0.03. The FPP was also associated with clinical variables: age (adjusted R 0.22 and p = 0.031) and sepsis (R adjusted 0.242 and p = 0.016). The vastus lateralis muscle was associated with the percentage of time in inactivity (R adjusted 0.235 and p = 0.01) and VMI use (adjusted R 0.2 and p = 0.03). Conclusion. Our results showed that FPP and the activation of the vastus lateralis muscle are associated with functional decline. In addition, muscle strength was associated with sit-up and standing gait testing. We found that these findings also showed an association of variables such as VMI, age, sepsis and percentage of time in inactivity. Therefore, the evaluation of these variables proved to be important to assist in the protection of functional loss in ICU patients

The aim of this diploma thesis is to design the control picking unit for the storage system Multitower. This work deals with the storage of rods, safety requirements and design of structures. The design part solves the actuator design, choice of chain tensioning system and torque transmission. The strength analysis of important components is solved in last part.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T16:24:00Z No. of bitstreams: 0<br>Made available in DSpace on 2016-11-11T16:24:00Z (GMT). No. of bitstreams: 0<br>A operação dinamicamente estável com zonas conjuntas foi obtida para um ressonador laser contendo dois bastões de Nd:YAG com módulos laser comerciais. O ressonador não polarizado gerou 115 W de potência no modo transversal fundamental TEM00. Quando polarizado por lâmina de Brewster atingiu 100,5W de potência de saída com 91% de polarização. Quando o ressonador foi polarizado com um polarizador de filme fino, obteve-se melhora na qualidade de feixe e um aumento na polarização, com o valor de M2 sendo 1,56 e 1,84 nas direções x e y respectivamente com 95,4% de polarização. A potência de saída foi, ao nosso conhecimento, a mais alta obtida para lasers polarizados operando no modo fundamental e usando módulos lasers comerciais de Nd:YAG bombeados lateralmente por diodos sem nenhuma preparação especial.<br>Dissertação (Mestrado em Tecnologia Nuclear)<br>IPEN/D<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

This diploma thesis deals with the creation of engineering design of holder of projector lens. The thesis is created in cooperation with department of development in Varroc Lighting Systems, s.r.o. Initial part provides a brief description of the development of lighting technology used in car´s headlamps. The following part describes solutions currently used in clamping the lens in holder. The main part of the thesis focuses on the design of holder of projector lens itself. Projector lenses testing provide critical values of cohesive failure of the lens material, which cannot be exceed during the process of lens fitting and its subsequent clamping. In the final part the engineering design is verified and optimized using finite element analysis.

In the face of technological advances in concrete science emerged so-called special concretes and, among these, the self-compacting concrete (SCC), developed in Japan in the 1980s. This concrete is currently considered one of the greatest advances in concrete technology in view of its numerous advantages (decrease of construction duration, decrease of concreting labor, improvement of the working environment, improvement of the quality and durability of structures etc.). The production of SCC requires different mix design methods related to those applied for conventional concrete. Among these differences are highlighted the determination of the aggregate compositions and the addition of fine materials and chemical admixtures. In the case of determining the aggregate composition, the method of unit mass has been applied in SCC. However, it is common the use of this method in binary combinations, but for ternary and quaternary combinations it is quite limited. Thus, this work aimed to analyze the influence of different combinations and compositions of aggregates, determined by the method of unit mass and void ratio, to obtaining and characterization of SCC. For this, initially the procedures of the method was standardized. It was used two types of natural fine and coarse aggregates with different physical characteristics. It was produced 9 different aggregate compositions, four binary, ternary and quaternary four. For each composition, one SCC was formulated, based on previous dosage studies. The selfcompactability properties of the concrete were analyzed by spreading, V funnel test and L box test. In case hardened state the compressive strength was determined. The results showed that different methods of execution procedures showed no differences. The method of unit mass proved to be efficient in determining aggregate compositions to supply the SCC. For the same volume and paste composition (cement, water, chemical and mineral admixtures) the quaternary composition was the most efficient in meeting the properties of selfcompactability and compressive strength.<br>Diante dos avanços tecnológicos na ciência do concreto surgiram os chamados concretos especiais e, dentre estes, pode-se citar o concreto autoadensável (CAA), desenvolvido no Japão, na década de 1980. Este concreto é atualmente considerado um dos maiores avanços na tecnologia do concreto tendo em vista as suas inúmeras vantagens (diminuição do tempo da obra, diminuição da mão de obra de concretagem, melhora o ambiente de trabalho, melhora a qualidade e durabilidade da estrutura e etc.). A obtenção do CAA requer métodos de dosagens diferentes dos aplicados em concretos convencionais. Dentre essas diferenças se destacam a determinação das composições de agregados e a adição de materiais finos e aditivos químicos. Em se tratando da determinação da composição de agregados o método da massa unitária vem sendo aplicado em CAA. Entretanto é comum sua utilização em combinações binárias, já para combinações ternárias e quaternárias é bastante limitado. Neste sentido, foram analisadas diferentes combinações e composições de agregados, determinadas pelo método da massa unitária e do índice de vazios, na obtenção e caracterização de CAA. Para isso, inicialmente procurou-se padronizar os procedimentos de execução do método. Utilizou-se dois tipos de agregados miúdos e graúdos naturais com diferentes características físicas, sendo produzidas 9 composições distintas, sendo quatro binárias, quatro ternárias e uma quaternária. Para cada composição foi formulado um CAA, tomando como base a dosagem em estudos prévios. As propriedades de autoadensabilidade do concreto foram analisadas através dos ensaios de espalhamento, funil V e caixa L. No estado endurecido a resistência à compressão foi determinada. Os resultados mostraram que os diferentes procedimentos de execução do método não apresentaram divergências. O método da massa unitária mostrou-se eficiente na determinação de composições de agregado para atendimento ao CAA. Para um mesmo volume e composição de pasta (cimento, água, aditivos e adições) a composição quaternária foi a mais eficiente no atendimento às propriedades de autoadensabilidade e resistência à compressão.

This master’s thesis deals with design of technological system for heating and process steam generation. The source of energy is a cogeneration unit. The thesis is divided into several parts. The first part is design of technological system and description. The second part is realized stoichiometric calculation and the thermal balance of steam boiler. The main part of thesis is design of the waste heat steam boiler. The thermal calculation, aerodynamic calculation, hydraulic calculation and strength calculation were made. The thesis also includes the drawing of designed waste heat steam boiler.

This diploma thesis focuses on Lycoming drive unit mounting used in two-seater plane of VLA category (the very light aircraft). In the beginning characteristics of currently produced Bristell aircrafts are described. Following chapters aim at research selection of new drive unit mounting based on multi-criteria decision analysis. For selected unit, the weight, center of mass and flight performance are calculated. Additionally, the construction of engine mount is proposed. According to CS-VLA and CS-23 stress level of mounting is defined followed by strength verification. Later in this thesis, a suitable engine cover for engine and cockpit cooling is proposed. A complete fuel system is described in following chapter. Last chapter deals with financial costs of re-engining as well as aircraft operational costs.

The thesis deal with design of coaxial high-speed gear box for small-scale turboshaft engines. At the beginning a study of problems was performed and for design concept was elected version of single-shaft turbo-engine with electric generator. Kinematic diagram, type of gear design, material and lubrication method was designed. Further was solved proposal of basic gearing parameters, choice of the number of tooth and basic proposal calculations were performed. Was performed check calculation of gearing, calculation of bearings durability and was processed design documentation in required range. Designed gear reducer has two stage with three coutershafts, that are deployed evenly about main axis of reducer. First stage is gear with external gearing, second stage with internal gearing. The thesis may be used as a template for next similar gear reducers design.

The determination of strain properties of masonry in the direction parallel to bed joints is a fundamental pre-requisite for designing structures, where masonry is subjected to horizontal stresses (e. g. strengthening with prestressing). The diploma thesis summarized techniques of determination of masonry modulus of elasticity presented in available literature. The goal is to suggest suitable methodology of determination of masonry modulus in direction parallel to the bed joints. In the practical part of the diploma thesis is that methodology verified by experimental test and results of tests are analyzed and discussed.

[EN] Phononic crystals are artificial materials formed by a periodic arrangement of inclusions embedded into a host medium, where each of them can be solid or fluid. By controlling the geometry and the impedance contrast of its constituent materials, one can control the dispersive properties of waves, giving rise to a huge variety of interesting and fundamental phenomena in the context of wave propagation. When a propagating wave encounters a medium with different physical properties it can be transmitted and reflected in lossless media, but also absorbed if dissipation is taken into account. These fundamental phenomena have been classically explained in the context of homogeneous media, but it has been a subject of increasing interest in the context of periodic structures in recent years as well. This thesis is devoted to the study of different effects found in sonic and phononic crystals associated with transmission, reflection and absorption of waves, as well as the development of a technique for the characterization of its dispersive properties, described by the band structure. We start discussing the control of wave propagation in transmission in conservative systems. Specifically, our interest is to show how sonic crystals can modify the spatial dispersion of propagating waves leading to control the diffractive broadening of sound beams. Making use of the spatial dispersion curves extracted from the analysis of the band structure, we first predict zero and negative diffraction of waves at frequencies close to the band-edge, resulting in collimation and focusing of sound beams in and behind a 3D sonic crystal, and later demonstrate it through experimental measurements. The focusing efficiency of a 3D sonic crystal is limited due to the strong scattering inside the crystal, characteristic of the diffraction regime. To overcome this limitation we consider axisymmetric structures working in the long wavelength regime, as a gradient index lens. In this regime, the scattering is strongly reduced and, in an axisymmetric configuration, the symmetry matching with acoustic sources radiating sound beams increase its efficiency dramatically. Moreover, the homogenization theory can be used to model the structure as an effective medium with effective physical properties, allowing the study of the wave front profile in terms of refraction. We will show the model, design and characterization of an efficient focusing device based on these concepts. Consider now a periodic structure in which one of the parameters of the lattice, such as the lattice constant or the filling fraction, gradually changes along the propagation direction. Chirped crystals represent this concept and are used here to demonstrate a novel mechanism of sound wave enhancement based on a phenomenon known as "soft" reflection. The enhancement is related to a progressive slowing down of the wave as it propagates along the material, which is associated with the group velocity of the local dispersion relation at the planes of the crystal. A model based on the coupled mode theory is proposed to predict and interpret this effect. Two different phenomena are observed here when dealing with dissipation in periodic structures. On one hand, when considering the propagation of in-plane sound waves in a periodic array of absorbing layers, an anomalous decrease in the absorption, combined with a simultaneous increase of reflection and transmission at Bragg frequencies is observed, in contrast to the usual decrease of transmission, characteristic in conservative periodic systems at these frequencies. For a similar layered media, backed now by a rigid reflector, out-of-plane waves impinging the structure from a homogeneous medium will increase dramatically the interaction strength. In other words, the time delay of sound waves inside the periodic system will be considerably increased resulting in an enhanced absorption, for a broadband spectral range.<br>[ES] Los cristales fonónicos son materiales artificiales formados por una disposición periódica de inclusiones en un medio, pudiendo ambos ser de carácter sólido o fluido. Controlando la geometría y el contraste de impedancias entre los materiales constituyentes se pueden controlar las propiedades dispersivas de las ondas. Cuando una onda propagante se encuentra un medio con diferentes propiedades físicas puede ser transmitida y reflejada, en medios sin pérdidas, pero también absorbida, si la disipación es tenida en cuenta. La presente tesis está dedicada al estudio de diferentes efectos presentes en cristales sónicos y fonónicos relacionados con la transmisión, reflexión y absorción de ondas, así como el desarrollo de una técnica para la caracterización de sus propiedades dispersivas, descritas por la estructura de bandas. En primer lugar, se estudia el control de la propagación de ondas en transmisión en sistemas conservativos. Específicamente, nuestro interés se centra en mostrar cómo los cristales sónicos son capaces de modificar la dispersión espacial de las ondas propagantes, dando lugar al control del ensanchamiento de haces de sonido. Haciendo uso de las curvas de dispersión espacial extraídas del análisis de la estructura de bandas, se predice primero la difracción nula y negativa de ondas a frecuencias cercanas al borde de la banda, resultando en la colimación y focalización de haces acústicos en el interior y detrás de un cristal sónico 3D, y posteriormente se demuestra mediante medidas experimentales. La eficiencia de focalización de un cristal sónico 3D está limitada debido a las múltiples reflexiones existentes en el interior del cristal. Para superar esta limitación se consideran estructuras axisimétricas trabajando en el régimen de longitud de onda larga, como lentes de gradiente de índice. En este régimen, las reflexiones internas se reducen fuertemente y, en configuración axisimétrica, la adaptación de simetría con fuentes acústicas radiando haces de sonido incrementa la eficiencia drásticamente. Además, la teoría de homogenización puede ser empleada para modelar la estructura como un medio efectivo con propiedades físicas efectivas, permitiendo el estudio del frente de ondas en términos refractivos. Se mostrará el modelado, diseño y caracterización de un dispositivo de focalización eficiente basado en los conceptos anteriores. Considérese ahora una estructura periódica en la que uno de los parámetros de la red, sea el paso de red o el factor de llenado, cambia gradualmente a lo largo de la dirección de propagación. Los cristales chirp representan este concepto y son empleados aquí para demostrar un mecanismo novedoso de incremento de la intensidad de la onda sonora basado en un fenómeno conocido como reflexión "suave". Este incremento está relacionado con una ralentización progresiva de la onda conforme se propaga a través del material, asociado con la velocidad de grupo de la relación de dispersión local en los planos del cristal. Un modelo basado en la teoría de modos acoplados es propuesto para predecir e interpretar este efecto. Se observan dos fenómenos diferentes al considerar pérdidas en estructuras periódicas. Por un lado, si se considera la propagación de ondas sonoras en un array periódico de capas absorbentes, cuyo frente de ondas es paralelo a los planos del cristal, se produce una reducción anómala en la absorción combinada con un incremento simultáneo de la reflexión y transmisión a las frecuencias de Bragg, de forma contraria a la habitual reducción de la transmisión, característica de sistemas periódicos conservativos a estas frecuencias. En el caso de la misma estructura laminada en la que se cubre uno de sus lados mediante un reflector rígido, la incidencia de ondas sonoras desde un medio homogéneo, cuyo frente de ondas es perpendicular a los planos del cristal, produce un gran incremento de la fuerza de<br>[CAT] Els cristalls fonònics són materials artificials formats per una disposició d'inclusions en un medi, ambdós poden ser sòlids o fluids. Controlant la geometría i el contrast d'impedàncies dels seus materials constituents, és poden controlar les propietats dispersives de les ondes, permetent una gran varietatde fenòmens fonamentals interessants en el context de la propagació d'ones. Quan una ona propagant troba un medi amb pèrdues amb propietats físiques diferents es pot transmetre i reflectir, però també absorbida si la dissipació es té en compte. Aquests fenòmens fonamentals s'han explicat clàssicament en el context de medis homogenis, però també ha sigut un tema de creixent interés en el context d'estructures periòdiques en els últims anys. Aquesta tesi doctoral tracta de l'estudi de diferents efectes en cristalls fonònics i sònics lligats a la transmissió, reflexió i absorció d'ones, així com del desenvolupament d'una tècnica de caracterització de les propietats dispersives, descrites mitjançant la estructura de bandes. En primer lloc, s'estudia el control de la propagació ondulatori en transmissió en sistemes conservatius. Més específicament, el nostre interés és mostrar com els cristalls sonors poden modificar la dispersió espacial d'ones propagants donant lloc al control de l'amplària per difracció dels feixos sonors. Mitjançant les corbes dispersió espacial obtingudes de l'anàlisi de l'estructura de bandes, es prediu, en primer lloc, la difracció d'ones zero i negativa a freqüències próximes al final de banda. El resultat és la collimació i focalització de feixos sonors dins i darrere de cristalls de so. Després es mostra amb mesures experimentals. L'eficiència de focalització d'un cristall de so 3D està limitada per la gran dispersió d'ones dins del cristall, que és característic del règim difractiu. Per a superar aquesta limitació, estructures axisimètriques que treballen en el règim de llargues longituds d'ona, i es comporten com a lents de gradient d'índex. En aquest règim, la dispersió es redueix enormement i, en una configuració axisimètrica, a causa de l'acoblament de la simetría amb les fonts acústiques que radien feixos sonors, l'eficiència de radiació s'incrementa significativament. D'altra banda, la teoria d'homogeneïtzació es pot utilitzar per a modelar, dissenyar i caracteritzar un dispositiu eficient de focalització basat en aquests conceptes. Considerem ara una estructura periòdica en la qual un dels seus paràmetres de xarxa, com ara la constant de xarxa o el factor d'ompliment canvia gradualment al llarg de la direcció de propagació. Els cristalls chirped representen aquest concepte i s'utilitzen ací per a demostrar un mecanisme nou d'intensificació d'ones sonores basat en el fenòmen conegut com a reflexió "suau". La intensificació està relacionada amb la alentiment progressiva de l'ona conforme propaga al llarg del material, que està associada amb la velocitat de grup de la relació de dispersió local en els diferents plànols del cristall. Es proposa un model basat en la teoria de modes acoblats per a predir i interpretar este efecte. Dos fenòmens diferents cal destacar quan es tracta d'estructures periòdiques amb dissipació. Per un costat, al considerar la propagació d'ones sonores en el plànol en un array periòdic de capes absorbents, s'observa una disminució anòmala de l'absorció i es combina amb un augment simultani de reflexió i transmissió en les freqüències de Bragg que contrasta amb la usual disminució de transmissió, característica dels sistemes conservatius a eixes freqüències. Per a un medi similar de capes, amb un reflector rígid darrere, les ones fora del pla incidint l'estructura des de un medi homogeni, augmentaran considerablement la interacció. En altres paraules, el retràs temporal de les ones sonores dins del sistema periòdic augmentarà significativament produint un augmen<br>Cebrecos Ruiz, A. (2015). Transmission, reflection and absorption in Sonic and Phononic Crystals [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/56463<br>TESIS<br>Premiado

Thesis (M.A.)--Florida State University, 2008.<br>Advisor: Eric Walker, Florida State University, College of Arts and Sciences, Dept. of English. Title and description from dissertation home page (viewed Aug. 7, 2008). Document formatted into pages; contains v, 67 pages. Includes bibliographical references.

Motor unit synchronization is phenomenon driven by a common input that results in the near-simultaneous firing of two or more motor units, which is referred to as short-term synchronization. The relationship between motor unit synchronization and force steadiness is still unclear, even after numerous experiments and simulations. Our main hypothesis was that the decreased force tetanus brought on by motor unit synchronization would be correlated to reduced steadiness at very low hand muscle forces. To determine if this correlation existed, young, healthy adults performed a submaximal, isometric pinch at four forces to determine if motor unit synchronization increased with a progressive decrease in force steadiness driven by reduced force levels. However, before performing synchronization analyses, we had to establish the best technique for measuring motor unit coherence, which quantifies the strength and frequency of a periodic common input. We used a pool of simulated spike trains with various firing rates, coefficients of variation (CV), common input frequencies and trial durations to explore the effects of data segmentation and spike train properties on coherence. We found that tapered segments overlapped by at least 50% maximized coherence measurements, regardless of taper type and that increasing common input frequency CV from 0.15-0.50 made coherence measurements unusable, even at high synchronization levels. During an isometric pinch at 2, 4, 8, and 12% of maximum digit force, we recorded thumb and index finger forces and EMG from the first dorsal interosseous (FDI) and adductor pollicis (AdP) muscles. As expected, the force CV dropped as each digit force increased. Pooled coherence revealed a dominant peak for the 2-10 Hz, but power for both digits' forces was limited to the 0-2 Hz bandwidth. There was a weak correlation for thumb force CV and coherence for within-AdP pairs, but no significant correlations were found for within-FDI pair coherence and finger force CV. Therefore, motor unit synchronization was not a strong driver of force steadiness for this protocol. To ensure that inherent firing rate nonstationarity of spike train data did not affect coherence measurements, we produced a new set of spike train pairs with firing rates and variances that approximated those for physiological motor units, which varied from 0-25%. Stationarity level was not significantly correlated to peak coherence (max R² = 0.082). Therefore, coherence measurements of spike train data with characteristics similar to those of the simulated trains were not significantly affected by nonstationarity. The establishment of the best method for computing coherence, the lack of a strong correlation between force steadiness and motor unit synchronization for submaximal isometric forces, and the knowledge that spike train nonstationarity has no significant effect on coherence measurements are all important discoveries needed for progress in the areas of basic neuromuscular function, motor unit synchronization, and pathological force unsteadiness.

Masters Research - Master of Philospohy (MPhil)<br>It has been shown that masonry material properties, in particular, unit flexural bond strength (ft), vary significantly throughout masonry structures, despite the fact that often only one type of brick and mortar are used. Unit flexural bond strength was previously identified as one of the most important material parameters contributing to the strength of clay brick unreinforced masonry (URM) walls in flexure. It was the objectives of this research, in the context of clay brick URM walls subject to vertical bending, to examine how unit flexural bond strength varied spatially in a clay brick URM wall, determine a best fit probability distribution function which can describe expected variability in unit flexural bond strength and determine how this variability and other factors affect wall behaviour and failure load using 3D non-linear finite element analysis (FEA). It was hoped that modelling a full sized clay brick URM wall subject to vertical bending using a 3D non-linear FEA model would more accurately predict wall failure load (compared to current analytical methods) and allow the examination of crack pattern development as the wall progresses to failure upon being laterally loaded. The first part of the research project was to conduct an experimental program to examine unit-to-unit spatial strength correlation within six full sized clay brick URM walls and to characterise a unit flexural bond strength probability distribution. It was observed that although weak correlation in unit flexural bond strength exists in some courses and between courses, these locations were difficult to predict and didn't follow any particular pattern relating to for example, mortar batch. Therefore, although somewhat counter-intuitive, the results indicate that statistically significant correlation between adjacent unit flexural bond strengths is not likely to be observed. It was also observed that clay brick wall unit flexural bond strengths obtained for all of the walls tested best fit a truncated Normal probability distribution. Strength of the brick/mortar interface appeared to be governed by factors relating to workmanship (and therefore mortar quality and moisture content), weather (which can affect material characteristics like brick suction rate) and inherent material variability. It would appear that brick suction rate can significantly affect the overall strength of a URM wall. Stochastic analysis was conducted for walls with and without uncorrelated spatial variability in unit flexural bond strength and associated tensile fracture energy (GfI ). It was found that the TNO DIANA 9.2 FEA package could be used to implement spatial variability of various material parameters and reasonably accurately model failure of clay brick URM walls in vertical bending. From the non-linear FEA model development stage, it was observed that because the brick/mortar bond has significantly more strength capacity in compression, it appears that the lateral load resistance of the wall comes from a combination of the ability of the brick/mortar bond to tensile soften while providing significant compressive resistance at the compressive edge. It was found for a spatial stochastic analysis with spatial variability in bond strength (referred to from now on as a spatial stochastic analysis), with COVs of 0.1, 0.3 and 0.5, that COV of wall failure loads were relatively small, being 0.02, 0.04 and 0.06 respectively. For the non-spatially varying stochastic analysis with fully correlated bond strength (now referred to as non-spatial stochastic analysis), with COVs of 0.1, 0.3 and 0.5, COV of wall failure loads were 0.07, 0.20 and 0.32 respectively. For the spatial stochastic analysis, it was found that with a bond strength COV increase from 0.1 to 0.5 the mean wall failure load dropped from 2.25 kPa to 2.0 kPa (an 11% reduction). Despite the relatively small drop in magnitude of the mean wall failure load with increase in bond strength COV, the mean wall failure loads were statistically different to one another. For the non-spatial stochastic analysis, mean failure load stayed relatively constant at 2.24-2.25 kPa. These results could be explained by examining the 3D wall progression to failure. For walls with spatial variability in bond strength, it is expected that wall failure load COVs would be smaller because those walls would consistently be composed of smaller valued bond strengths which would consistently contribute to weakness in the wall. For the non-spatial wall simulations, this effect would not occur as failure load is determined by one uniform weak or strong bond strength. It was proposed that failure of a clay brick URM wall is not governed by one course only cracking, but rather, instability in the wall is governed by several courses in the vicinity of locations of large bending moment. It was shown that various current stochastic approximations which employ a unit failure hypotheses in combination with a linear/elastic approximation for first cracking load all underestimated wall capacity significantly. The reason for this is suggested as being because all hypotheses only assume failure is governed by one course and linear/elastic theory only considers the tensile capacity of a joint and neglects strength capacity available as a result of joint tension softening and the resistance to failure provided by compressive strength on the compression side of the wall. The hypotheses also don’t take into consideration factors which affect overall wall bond strength mean which result from influences such as workmanship, weather and material variability factors, such as (for example), variation in brick suction rate due to weather conditions which can make the overall strength of the wall stronger or weaker. Based upon a comparison in wall failure load COV for the spatial and non-spatial stochastic wall analysis results, a more realistic approach for future modelling attempts of spatial variability in masonry material properties is suggested. This would address the issue of external factors such as workmanship and weather on the overall strength of the wall, as well as the inherent bond strength variability due to material variability. For walls with spatial variability in bond strength, upon examination of numerous wall simulation results, several crack patterns were witnessed and are discussed.

Masters Research - Master of Philospohy (MPhil)<br>It has been shown that masonry material properties, in particular, unit flexural bond strength (ft), vary significantly throughout masonry structures, despite the fact that often only one type of brick and mortar are used. Unit flexural bond strength was previously identified as one of the most important material parameters contributing to the strength of clay brick unreinforced masonry (URM) walls in flexure. It was the objectives of this research, in the context of clay brick URM walls subject to vertical bending, to examine how unit flexural bond strength varied spatially in a clay brick URM wall, determine a best fit probability distribution function which can describe expected variability in unit flexural bond strength and determine how this variability and other factors affect wall behaviour and failure load using 3D non-linear finite element analysis (FEA). It was hoped that modelling a full sized clay brick URM wall subject to vertical bending using a 3D non-linear FEA model would more accurately predict wall failure load (compared to current analytical methods) and allow the examination of crack pattern development as the wall progresses to failure upon being laterally loaded. The first part of the research project was to conduct an experimental program to examine unit-to-unit spatial strength correlation within six full sized clay brick URM walls and to characterise a unit flexural bond strength probability distribution. It was observed that although weak correlation in unit flexural bond strength exists in some courses and between courses, these locations were difficult to predict and didn����t follow any particular pattern relating to for example, mortar batch. Therefore, although somewhat counter-intuitive, the results indicate that statistically significant correlation between adjacent unit flexural bond strengths is not likely to be observed. It was also observed that clay brick wall unit flexural bond strengths obtained for all of the walls tested best fit a truncated Normal probability distribution. Strength of the brick/mortar interface appeared to be governed by factors relating to workmanship (and therefore mortar quality and moisture content), weather (which can affect material characteristics like brick suction rate) and inherent material variability. It would appear that brick suction rate can significantly affect the overall strength of a URM wall. v Stochastic analysis was conducted for walls with and without uncorrelated spatial variability in unit flexural bond strength and associated tensile fracture energy (GfI ). It was found that the TNO DIANA 9.2 FEA package could be used to implement spatial variability of various material parameters and reasonably accurately model failure of clay brick URM walls in vertical bending. From the non-linear FEA model development stage, it was observed that because the brick/mortar bond has significantly more strength capacity in compression, it appears that the lateral load resistance of the wall comes from a combination of the ability of the brick/mortar bond to tensile soften while providing significant compressive resistance at the compressive edge. It was found for a spatial stochastic analysis with spatial variability in bond strength (referred to from now on as a spatial stochastic analysis), with COVs of 0.1, 0.3 and 0.5, that COV of wall failure loads were relatively small, being 0.02, 0.04 and 0.06 respectively. For the non-spatially varying stochastic analysis with fully correlated bond strength (now referred to as non-spatial stochastic analysis), with COVs of 0.1, 0.3 and 0.5, COV of wall failure loads were 0.07, 0.20 and 0.32 respectively. For the spatial stochastic analysis, it was found that with a bond strength COV increase from 0.1 to 0.5 the mean wall failure load dropped from 2.25 kPa to 2.0 kPa (an 11% reduction). Despite the relatively small drop in magnitude of the mean wall failure load with increase in bond strength COV, the mean wall failure loads were statistically different to one another. For the non-spatial stochastic analysis, mean failure load stayed relatively constant at 2.24-2.25 kPa. These results could be explained by examining the 3D wall progression to failure. For walls with spatial variability in bond strength, it is expected that wall failure load COVs would be smaller because those walls would consistently be composed of smaller valued bond strengths which would consistently contribute to weakness in the wall. For the non-spatial wall simulations, this effect would not occur as failure load is determined by one uniform weak or strong bond strength. It was proposed that failure of a clay brick URM wall is not governed by one course only cracking, but rather, instability in the wall is governed by several courses in the vicinity of locations of large bending moment. It was shown that various current stochastic approximations which employ a unit failure hypotheses in combination with a linear/elastic approximation for first cracking load all underestimated wall capacity significantly. The reason for this is suggested as being vi because all hypotheses only assume failure is governed by one course and linear/elastic theory only considers the tensile capacity of a joint and neglects strength capacity available as a result of joint tension softening and the resistance to failure provided by compressive strength on the compression side of the wall. The hypotheses also don’t take into consideration factors which affect overall wall bond strength mean which result from influences such as workmanship, weather and material variability factors, such as (for example), variation in brick suction rate due to weather conditions which can make the overall strength of the wall stronger or weaker. Based upon a comparison in wall failure load COV for the spatial and non-spatial stochastic wall analysis results, a more realistic approach for future modelling attempts of spatial variability in masonry material properties is suggested. This would address the issue of external factors such as workmanship and weather on the overall strength of the wall, as well as the inherent bond strength variability due to material variability. For walls with spatial variability in bond strength, upon examination of numerous wall simulation results, several crack patterns were witnessed and are discussed.

碩士<br>國立成功大學<br>機械工程學系碩博士班<br>100<br>In recent years, in order to reduce the cost of dental bridge produced using hollow design, the metal part of the dental bridge to save material. However, the research about the change dental bridge is seldom seen. The purpose of this study was to investigate the stresses and deformations in porcelain-fused-to-metal bridge by using finite element method(FEM), The parameters under consideration were loading modes and metal frame shapes. The dental bridge model consists of the outermost layer of the ceramic materials, metal frame design of the bridge and ceramic materials filled in the hollow part of metal. Two different loading models, in which loadings are applied on the pontic and the entire metal-ceramic dental bridge, respectively, are simulated and analyzed. And then the 3-D stress and deformation are performed by using the finite element code ANSYS. The results show that the stress will be higher at the location of the dental bridge connecting the body and dental bridge. Moreover, external ceramic part of the stress will be greater than the internal stress of the metal frame. The hollow design of the pontic has no significant effect on the strength of the dental bridge structure. In addition, phenomenon of interface debonding between the ceramic and metal may be happened as the loading is higher than 1000N.

Mobile offshore drilling units are being used in the Gulf of Mexico to produce oil and gas. Anchoring systems such as drag embedment anchors and vertically loaded anchors are used to keep these units in place. Past mooring system failures due to hurricanes in 2004 and 2005 initiated a need to better understand the performance of these anchors to in-plane and out-of-plane loading conditions. In-plane and out-of-plane loading cause the anchor to translate or rotate in the directions of its six degrees of freedom. Behavior and holding capacity of the anchors when loaded in each of is six degrees of freedom are important in understanding and predicting their behavior. An experimental program was devised to investigate the behavior of anchors in pure translation and rotation loading. The scaled-model anchors were embedded at a measured depth in a soil bed of clay with an undrained shear strength between 10 and 20 psf and then loaded to failure. A rotation testing frame was designed to impose rotational loading in the yaw, roll and pitch directions. Test results from the experimental program are consistent and repeatable. The bearing factors for pure bearing fell well within the range of existing experimental and analytical studies on simple plates. Bearing factors for in-plane and out-of-plane shear and for all rotations are higher than those for simple plates due to presence of the shank. When the resistance is normalized by area of the fluke, the wider model provide greater normalized resistance to yawing, similar normalized resistance to pitching and rolling and less normalized resistance to bearing and shearing. It was concluded that the holding capacity of an anchor in its six degrees of freedom depends largely on its geometry, including the fluke and the shank.<br>text

碩士<br>國立成功大學<br>國際經營管理研究所<br>102<br>Organizations today are on the hunt for employees who are willing to engage in extra-role behaviors for the benefit of the firm. One such extra-role behavior, employee voice, has been shown in academic research and managerial applications to have a positive effect on the organization. This study moves to a group level analysis of employee voice by examining two potential determinants of group voice behavior, work unit TMX and group voice climate. In addition, the dispersion constructs of TMX differentiation and climate strength are analyzed as moderating influences on the relationships between group voice climate, work unit TMX, and group voice behavior. After the data was collected, confirmatory factor analysis and ICCI/ICC2 were performed to test the validity of the items and the group respondent variability. Hierarchical Regression also completed for all five relationships. The results show a positive relationship between group voice behavior and its antecedents, group voice climate and work unit TMX. Climate strength and TMX differentiation were not determined to have moderating effects on the direction relationships between group voice behavior and its determinants. These results broaden the field of employee voice at the group level while still leaving some questions unanswered for future researchers to explore.

碩士<br>國防大學管理學院<br>運籌管理學系<br>101<br>The decreasing of military equipments and weapons are becoming the trend in recent years. The National Defense Ministry considering the factors of enemies threaten, fighting concept adjustment and defense resources limitation etc. started the military downsizing program from 1st July 1997, coming up with the 2nd and 3rd military downsizing programs plus the soldier recruit change policy, and expect the military staff lessen from 22 to 18 thousand people at 31st Dec. 2014. At the same time, in a series of organizational combination and positions cutting down, the organization members adjust revolution pressure of the combination project in new working unit, even cause the problems like resisted behavior or cannot access the new work etc. that is the urgently overcome issues in defense organization change. Therefore, the main research purpose is discussing the relationship of members resisting intensity, range, and organizational preventin strategies under the uncertainty of organization change. The questionnaire objects are the A unit of Logistics Headquarter, and distribute 70 questionnaires and recoveries 100%. The results show that it is different when members resisting intensity in uncertainty organization change. The reason is the members are used to the uniform working module. When the uncertainty occurs, it needs more time and higher cost because it cannot control the future organization change. According to the research results, an objective analysis of the Compare Organization prevention strategies provides the unit members behavior of resisting strength and range, and response to the reaction relationship provide the reference of organization change and improve the working performance and efficiency.

Les moteurs de recherche font partie de notre vie quotidienne. Actuellement, plus d’un tiers de la population mondiale utilise l’Internet. Les moteurs de recherche leur permettent de trouver rapidement les informations ou les produits qu'ils veulent. La recherche d'information (IR) est le fondement de moteurs de recherche modernes. Les approches traditionnelles de recherche d'information supposent que les termes d'indexation sont indépendants. Pourtant, les termes qui apparaissent dans le même contexte sont souvent dépendants. L’absence de la prise en compte de ces dépendances est une des causes de l’introduction de bruit dans le résultat (résultat non pertinents). Certaines études ont proposé d’intégrer certains types de dépendance, tels que la proximité, la cooccurrence, la contiguïté et de la dépendance grammaticale. Dans la plupart des cas, les modèles de dépendance sont construits séparément et ensuite combinés avec le modèle traditionnel de mots avec une importance constante. Par conséquent, ils ne peuvent pas capturer correctement la dépendance variable et la force de dépendance. Par exemple, la dépendance entre les mots adjacents "Black Friday" est plus importante que celle entre les mots "road constructions". Dans cette thèse, nous étudions différentes approches pour capturer les relations des termes et de leurs forces de dépendance. Nous avons proposé des méthodes suivantes: ─ Nous réexaminons l'approche de combinaison en utilisant différentes unités d'indexation pour la RI monolingue en chinois et la RI translinguistique entre anglais et chinois. En plus d’utiliser des mots, nous étudions la possibilité d'utiliser bi-gramme et uni-gramme comme unité de traduction pour le chinois. Plusieurs modèles de traduction sont construits pour traduire des mots anglais en uni-grammes, bi-grammes et mots chinois avec un corpus parallèle. Une requête en anglais est ensuite traduite de plusieurs façons, et un score classement est produit avec chaque traduction. Le score final de classement combine tous ces types de traduction. Nous considérons la dépendance entre les termes en utilisant la théorie d’évidence de Dempster-Shafer. Une occurrence d'un fragment de texte (de plusieurs mots) dans un document est considérée comme représentant l'ensemble de tous les termes constituants. La probabilité est assignée à un tel ensemble de termes plutôt qu’a chaque terme individuel. Au moment d’évaluation de requête, cette probabilité est redistribuée aux termes de la requête si ces derniers sont différents. Cette approche nous permet d'intégrer les relations de dépendance entre les termes. Nous proposons un modèle discriminant pour intégrer les différentes types de dépendance selon leur force et leur utilité pour la RI. Notamment, nous considérons la dépendance de contiguïté et de cooccurrence à de différentes distances, c’est-à-dire les bi-grammes et les paires de termes dans une fenêtre de 2, 4, 8 et 16 mots. Le poids d’un bi-gramme ou d’une paire de termes dépendants est déterminé selon un ensemble des caractères, en utilisant la régression SVM. Toutes les méthodes proposées sont évaluées sur plusieurs collections en anglais et/ou chinois, et les résultats expérimentaux montrent que ces méthodes produisent des améliorations substantielles sur l'état de l'art.<br>Search engine has become an integral part of our life. More than one-third of world populations are Internet users. Most users turn to a search engine as the quick way to finding the information or product they want. Information retrieval (IR) is the foundation for modern search engines. Traditional information retrieval approaches assume that indexing terms are independent. However, terms occurring in the same context are often dependent. Failing to recognize the dependencies between terms leads to noise (irrelevant documents) in the result. Some studies have proposed to integrate term dependency of different types, such as proximity, co-occurrence, adjacency and grammatical dependency. In most cases, dependency models are constructed apart and then combined with the traditional word-based (unigram) model on a fixed importance proportion. Consequently, they cannot properly capture variable term dependency and its strength. For example, dependency between adjacent words “black Friday” is more important to consider than those of between “road constructions”. In this thesis, we try to study different approaches to capture term relationships and their dependency strengths. We propose the following methods for monolingual IR and Cross-Language IR (CLIR): We re-examine the combination approach by using different indexing units for Chinese monolingual IR, then propose the similar method for CLIR. In addition to the traditional method based on words, we investigate the possibility of using Chinese bigrams and unigrams as translation units. Several translation models from English words to Chinese unigrams, bigrams and words are created based on a parallel corpus. An English query is then translated in several ways, each producing a ranking score. The final ranking score combines all these types of translations. We incorporate dependencies between terms in our model using Dempster-Shafer theory of evidence. Every occurrence of a text fragment in a document is represented as a set which includes all its implied terms. Probability is assigned to such a set of terms instead of individual terms. During query evaluation phase, the probability of the set can be transferred to those of the related query, allowing us to integrate language-dependent relations to IR. We propose a discriminative language model that integrates different term dependencies according to their strength and usefulness to IR. We consider the dependency of adjacency and co-occurrence within different distances, i.e. bigrams, pairs of terms within text window of size 2, 4, 8 and 16. The weight of bigram or a pair of dependent terms in the final model is learnt according to a set of features. All the proposed methods are evaluated on several English and/or Chinese collections, and experimental results show these methods achieve substantial improvements over state-of-the-art baselines.

Title: Spectral Analysis of Electromyography Data of Power Lifters Objectives: The aim of this thesis is a description of muscle activity and its measu- rement using electromyography (EMG), description of parameters of EMG signal and their relationship to neuromuscular physiology. The aim of the practical part is an implementation of spectral analysis of EMG data of power lifters when performing 4 series of 5 split-squats carrying loading in one hand. Methods: The spectral analysis of EMG data of 35 athletes is presented. The athletes performed 4 series of 5 split-squats with one sided loading. The loading was 25% and 50% of their body mass and the carrying position was homolateral and contralateral to stance leg. Muscles chosen for measurement were vastus medialis obliquus, vastus lateralis obliquus, gluteus medius and biceps femoris of both sides. The implementation of digital signal proces- sing algorithm was done using Matlab and its Signal Processing Toolbox. The spectral analysis was implemented using discrete Fourier transform with sliding 256-sample window size and 32-sample window increment. The resulting spectrogram was divided into parts based on smoothed EMG. Median frequency for each split-squat was calculated. For the statistical processing we used median frequency differencies...