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Dissertations / Theses on the topic 'Distance function'
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1
Regula, Meyer Lisa. "Genetic distance as a function of geographic distance in Ohio Dusky salamanders." Connect to resource, 2005. http://hdl.handle.net/1811/470.
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Thesis (Honors)--Ohio State University, 2005.Title from first page of PDF file. Document formattted into pages: contains 20 p. Includes bibliographical references (p. 12-14). Available online via Ohio State University's Knowledge Bank.
2
Mody, Ravi. "Optimizing the distance function for nearest neighbors classification." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p1470299.
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Thesis (M.S.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed December 2, 2009). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 48-49).
3
Parker, M. J. "Mean values and distance functions in potential theory." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382068.
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Rasouli, Alireza. "Calibrating the Distance-Deterrence Function for the Perth Metropolitan Area." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/59663.
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The Perth metropolitan area and its surrounding regions have been expanding rapidly. With this rapid growth, consideration should be given to strategic modelling. Development of reliable model depends significantly on the calibrated parameters to reflect the existing situation. Deterrence functions play an important role for distribution of the trips and would simulate the trip distances. Therefore they should be calibrated for any particular models. This study aims to review the most common deterrence functions and calibrate them for the work trips.
5
Singh, Rupesh Kumar. "Distance Learning and Attribute Importance Analysis by Linear Regression on Idealized Distance Functions." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1495909607902884.
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Ragipi, Rushid Ajsuna. "Technical efficiency of Swedish district courts : - a stochastic distance function analysis." Thesis, Linnéuniversitetet, Institutionen för nationalekonomi och statistik (NS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-78120.
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The aim of this study is to measure Swedish district courts’ technical efficiency for the period between 2000 and 2016 by applying the stochastic distance function approach. Although a very important issue from a policy perspective, a few studies have measured the efficiency of the courts. The narrow literature is also limited to using nonparametric methods, such as the DEA. The stochastic distance function has not been used for this purpose before and hence this is the first study to do so. The estimated mean score of technical efficiency is 93%. However, this study observes that efficiency levels increase throughout the studied period. Large variations between efficiency levels of different courts are also observed. Policy recommendations are to learn from courts with higher efficiency levels.
7
Östman, Martin. "Video Coding Based on the Kantorovich Distance." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2330.
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In this Master Thesis, a model of a video coding system that uses the transportation plan taken from the calculation of the Kantorovich distance is developed. The coder uses the transportation plan instead of the differential image and sends it through blocks of transformation, quantization and coding.
The Kantorovich distance is a rather unknown distance metric that is used in optimization theory but is also applicable on images. It can be defined as the cheapest way to transport the mass of one image into another and the cost is determined by the distance function chosen to measure distance between pixels. The transportation plan is a set of finitely many five-dimensional vectors that show exactly how the mass should be moved from the transmitting pixel to the receiving pixel in order to achieve the Kantorovich distance between the images. A vector in the transportation plan is called an arc.
The original transportation plan was transformed into a new set of four-dimensional vectors called the modified difference plan. This set replaces the transmitting pixel and the receiving pixel with the distance from the transmitting pixel of the last arc and the relative distance between the receiving pixel and the transmitting pixel. The arcs where the receiving pixels are the same as the transmitting pixels are redundant and were removed. The coder completed an eleven frame sequence of size 128x128 pixels in eight to ten hours.
8
Corbin, Sierra Fontaine. "Keeping Your Friends Close: Perceived Distance as a Function of Psychological Closeness." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1497502217239512.
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Tang, Siu-shing. "Integrating distance function learning and support vector machine for content-based image retrieval /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?CSED%202006%20TANG.
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Furumatsu, Noriko, and Jiro Nemoto. "Scale and scope economies of Japanese private universities revisited with an input distance function approach." Springer, 2014. http://hdl.handle.net/2237/20574.
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Dharmarajan, Lakshmi. "Structure-Function Studies on Two Phosphoenolpyruvate Carboxylases." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77040.
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Phosphoenolpyruvate carboxykinase (PEPCK) and phosphoenolpyruvate carboxylase (Pepc) are two important CO₂-fixation enzymes which share a similar reaction mechanism. Both operate through a lid-gated active site and have a hypothesized enol-pyruvate intermediate in their catalytic pathway. While PEPCK is an important metabolic enzyme in animals and plays a broad role in cataplerosis, gluconeogenesis and glyceroneogenesis, Pepc reaction in plants catalyzes the first committed step in CO₂ fixation in CAM and C₄ plants via Rubisco. We are studying the structure-function aspects of both enzymes, with a goal of discovering new elements in these enzymes which can modulate catalysis. We have undertaken an interdisciplinary approach for this work and have shown that a combination of experimental and computational techniques can be complementary and can provide novel information.
We have determined that in human PEPCK, Tyr235 forms an anion-quadrupole interaction with the carboxylate of PEP and thus positions the latter with respect to the enzyme-bound Mn²+ for optimal phosphoryl transfer and catalysis. We have also identified Pro82 as a catalytically influential residue in this enzyme. Using molecular dynamics simulations we have noted that absence of ligands induces active-site lid opening in GTP-PEPCKS and we have made the first observation of the intermediary structures of the lid opening event, the dynamics of which is an important element that controls GTP-PEPCK catalysis.
We have determined the first three-dimensional crystal structure of an archaeal-type Pepc, i.e. C. perfringens PepcA. Our experimental data also provide information about the oligomerization of PepcAs and reveal that aspartate inhibits the C. perfringens enzyme competitively compared to the allosteric inhibition in Pepcs. Structure-based modeling has led to the identification of putative aspartate- and bicarbonate-binding residues in C. perfringens PepcA, of which Arg82, His11, Ser201, Arg390, Lys340, Arg342 and Arg344 probably play an important role.Ph. D.
12
Trappe, Scott W. "Skeletal muscle morphology and function in former elite distance runners : a 20 year follow-up." Virtual Press, 1994. http://liblink.bsu.edu/uhtbin/catkey/902507.
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The purpose of this investigation was to examine the effects of 20 years of distance running training on the morphological and functional characteristics of skeletal muscle. Sixty men (current age = 49.2 ± 2.4 yr.) were first studied between 1966-1974 when they were all highly trained. Based on their training regimens in the interim between testing, subjects were described as highly trained (HI), fitness trained (FIT) or untrained (UT). Gastrocnemius muscle biopsy samples revealed an increase (p<0.05) in the proportion of type I fibers of the FIT (52.9 ± 5.3 vs. 61.9 ± 5.2%) and UT (56.3 ± 2.9 vs. 65.4 ± 3.8%) groups, while the HI group, who was initially characterized by a high percentage (>70%) of type I muscle fibers, was unchanged. Among the elite distance runners who had continued high volume, high intensity running, succinate dehydrogenase (SDH) activity and type I and type II muscle fiber areas were similar between evaluations. In 1993, the HI group had higher (p<0.05) SDH and citrate synthase (CS) activities compared with the FIT and UT groups, whereas phosphorylase activity did not differ. Capillary density and capillary-to-fiber ratio were also greater (p<0.05) in the HI group compared with the other two groups. Isokinetic plantar flexion strength at 60°/s and 180°/s and cross-sectional area (CT scans) of the lower leg (gastrocnemius and soleus) were similar among groups. These data suggest that aging may have a significant effect upon the distribution of muscle fibers and may be dependent upon fiber composition as a young adult. In addition, sustained endurance training appears to maintain the oxidative characteristics of the skeletal muscle, but does not provide an advantage in absolute calf muscle strength compared with individuals who train considerably less or not at all.School of Physical Education
13
Hassan, Muhammad Yusuf. "Left ventricular function after ultra-distance triathlon : response is dependent on the cardiac loading conditions." Master's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/25803.
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The purpose of this thesis is to establish if there is any evidence to support the hypothesis that altered ventricular loading conditions after the cessation of exercise may cause "cardiac fatigue". The studies that have shown post-exercise "cardiac fatigue" have not controlled for either preload or afterload or both, before and after exercise. These studies may rather have identified the effects of alterations in peripheral vascular function on left ventricular function after prolonged exercise. The research study in this thesis is to evaluate if the loading conditions of the heart affect the echocardiographic measurements after exercise that may be misinterpreted as "cardiac fatigue". Echocardiography as a tool of cardiac evaluation cannot be done during exercise because of the technical difficulty of doing a cardiac ultrasound on a human being in motion. The studies that have investigated post exercise "cardiac fatigue" have therefore measured cardiac function after exercise and retrospectively assumed that the cardiac dysfunction was present during exercise since the cardiac demands are at their peak during exercise. However, the post exercise period may be associated with altered loading conditions that may cause changes in the echocardiographic measurements that are similar to cardiac abnormalities.
14
Mykhaylyk, O. O. "Structural Characterization of Colloidal Core-shell Polymer-based Nanoparticles Using Small-angle X-ray Scattering." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/34779.
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Colloidal particle complexes are often characterized by small angle X-ray scattering (SAXS) techniques.
The present work demonstrates SAXS analysis of inhomogeneous core-shell nanoparticles with complex
shell morphologies. Different experimental techniques such as variation of particle composition and
contrast variation method, and analytical techniques such as Monte Carlo simulation and indirect Fourier
transformation are applied to obtain structural parameters of polymer-based core-shell nanoparticles. It is
shown that the SAXS results are consistent with other measurements performed by electron microscopy,
atomic force microscopy, dynamic light scattering, thermogravimetry, helium pycnometry and BET.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34779
15
Uhlenbroek, Charlotte. "The structure and function of the long-distance calls given by male chimpanzees in Gombe National Park." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388038.
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Samuel, Carlos. "Frequency analysis of hazardous material transportation incidents as a function of distance from origin to incident location." [Ames, Iowa : Iowa State University], 2007.
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Posireddy, Sudhir Reddy. "Optimization of Meshfree Method with Distance Fields using Localized Solution Structure and Radial Basis Function Collocation Method." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/279.
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To avoid the meshing problems with traditional engineering analysis methods many meshfree methods have been developed, and one of the most powerful methods proposed is meshfree method with distance fields. This research work aims at reducing the computational cost of meshfree method with distance fields. The main idea of the proposed approach is to apply a solution structure operator only to those basis functions whose supports are in the vicinity of the boundary and leave other basis functions unaffected. Unfortunately, straightforward implementation of this approach leads to elevated errors in partial derivatives of the solution. To overcome this drawback I propose to modify distance fields in such a way that they behave as a Euclidean distance in the region near the boundary and have smooth transition to a constant value within some distance away from the boundary. The uniqueness of the proposed method over other approaches is its adaptability to all kinds of boundary conditions. This narrow band technique improves the computational cost of meshfree method with distance fields with reasonable impact on accuracy. Another technique proposed in this work is to glue the global solution structures of meshfree method with distance fields with radial basis functions (RBF) and collocation technique. RBF with collocation method itself is proved to give good accurate results with less computational cost [12]. So using RBF-collocation technique with meshfree method with distance fields demands for more accuracy even with less computational cost. Later, these techniques are applied to solve heat transfer problems and the results are compared with global solution techniques to show that the proposed methods are close to global approach and computationally very effective.
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Wrobel, Shannon Alicia. "Multi-Function LIDAR Sensors for Non-Contact Speed and Track Geometry Measurement in Rail Vehicles." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23134.
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A Doppler LIght Detection And Ranging (LIDAR or lidar) system is studied for the application of measuring train ground speed in a non-contacting manner, as an alternative to the current train speed measurement devices such as wheel-mounted tachometers or encoders. The ability to accurately measure train speed and distance is a critical part of monitoring track geometry conditions.Wheel-mounted tachometer speed measurements often fluctuate due to wheel vibrations, change in wheel diameter, or wheel slip affecting the measurement accuracy. Frequent calibrations are needed to account for changes in wheel diameter due to wear. Additionally, the high levels of vibrations at the wheel can cause occasional mechanical failure of the encoder.
This thesis examines LIDAR as a non-contact train speed measurement device as a direct retrofit for wheel-mounted encoders. LIDAR uses Doppler technology to accurately measure train speed. The LIDAR system consists of two laser sensors and can be installed on either the car body or the truck on the underside of the train. The sensors measure the true ground speed of each rail, from which the track curvature can then be assessed based on the difference between the right and left rail speeds. The LIDAR train speed, distance, and curvature results are then evaluated against encoder readings and other conventional train measurement devices.
Various tests were performed, including field-testing onboard a track geometry railcar operated by Norfolk Southern for evaluating the efficacy, accuracy, and durability of the LIDAR system; and laboratory tests on a 40-foot rail panel for assessing the ability to obtain measurements at super low speeds.
The test results indicate that when compared with other conventional means used by the railroad industry, LIDAR is capable of accurately measuring train speed and distance from speeds as slow as 0.3 mph and up to 100 mph. Additionally, the curvature
measurements proved to be as accurate as Inertial Measurement Units (IMUs) that are commonly used in track geometry measurement railcars.
Master of Science
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Maupin, Richard E. "Luminosity classification of red stars and distances to nearby red dwarfs." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1259760.
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This investigation in the 24 Kapteyn Selected Areas along the celestial equator examined 21 red dwarf stars identified in an objective-prism survey. These stars were classified as red dwarf stars using light at wavelengths between 5800 A and 6800 A. Using calcium-hydride-based luminosity classification, this study found 13 of these stars to be red giant stars, and only 6 stars were found to be red dwarfs. One star was determined to be warm star. One star was not clearly distinguishable as a dwarf or giant. Distance calculations for the red dwarf stars found that these stars lie within 40 parsecs of the sun.Department of Physics and Astronomy
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Durak, Bahadir. "A Classification Algorithm Using Mahalanobis Distance Clustering Of Data With Applications On Biomedical Data Sets." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612852/index.pdf.
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The concept of classification is used and examined by the scientific community
for hundreds of years. In this historical process, different methods and algorithms
have been developed and used.
Today, although the classification algorithms in literature use different methods,
they are acting on a similar basis. This basis is setting the desired data into classes
by using defined properties, with a different discoursean effort to establish a relationship between known features with unknown result. This study was intended to bring a different perspective to this common basis. In this study, not only the basic features of data are used, the class of the data is also included as a parameter. The aim of this method is also using the information in the algorithm that come from a known value. In other words, the class, in which the data is included, is evaluated as an input and the data set is transferred to a higher dimensional space which is a new working environment. In this new environment it is not a classification problem anymore, but a clustering problem. Although this logic is similar with Kernel Methods, the methodologies are different from the way that how they transform the working space. In the projected new space, the clusters based on calculations performed with the Mahalanobis Distance are evaluated in original space with two different heuristics which are center-based and KNN-based algorithm. In both heuristics, increase in classification success rates achieved by this methodology. For center based algorithm, which is more sensitive to new input parameter, up to 8% of enhancement is observed.
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Hägglöf, Peter. "Plasminogen activator inhibitor type-1 : structure-function studies and its use as a reference for intramolecular distance measurements." Doctoral thesis, Umeå University, Medical Biochemistry and Biophsyics, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-177.
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Inhibitors belonging to the serpin (serine protease inhibitor) family control proteases involved in various physiological processes. All serpins have a common tertiary structure based on the dominant b-sheet A, but they have different inhibitory specificity. The specificity of a serpin is determined by the Pl-Pl’ peptide bond acting as a bait for the target protease which is made up of an exposed reactive centre loop (RCL). The serpin plasminogen activator inhibitor type-1 (PAI-1) is the main physiological inhibitor of urokinase-type and tissue-type plasminogen activators (uPA and tPA, respectively). Elevated plasma levels of PAI-l have been correlated with a higher risk of deep venous thrombosis, and PAI-1 is a risk factor for recurrent myocardial infarction. Furthermore, PAI-1 has a role in cell migration and has been suggested to regulate tumor growth and angiogenesis. PAI-1 is unique among the serpins in that it can spontaneously and rapidly convert into its latent form. This involves full insertion of the RCL into b-sheet A.
There were two partially overlapping goals for this thesis. The first was to use latent PAI-1 as model for development of a fluorescence-based method, Donor-Donor Energy Migration for intramolecular distance measurements. The second goal was to use DDEM, together with other biochemical methods, to reveal the structure of the PAI-1/uPA complex, the conformation of the RCL in active PAI-1, and molecular determinants responsible for the conversion of PAI-1 from the active to the latent form.
The use of molecular genetics for introduction of fluorescent molecules enables the use of DDEM to determine intramolecular distances in a variety of proteins. This approach can be applied to examin the overall molecular dimensions of proteins and to investigate structural changes upon interactions with specific target molecules. In this work, the accuracy of the DDEM method has been evaluated by experiments with the latent PAI-1 for which X-ray structure is known. Our data show that distances approximating the Förster radius (57±1 Å) obtained by DDEM are in good agreement (within 5.5 Å) with the distances obtained by X-ray crystallography.
The molecular details of the inhibitory mechanism of serpins and the structure of the serpin/protease complex have remained unclear. To obtain the structural insights required to discriminate between different models of serpin inhibition, we used fluorescence spectroscopy and cross-linking techniques to map sites of PAI-1/uPA interaction, and distance measurement by DDEM to triangulate the position of the uPA in the complex. The data have demonstrated clearly that in the covalent PAI-1/uPA complex, the uPA is located at the distal end of the PAI-1 molecule relative to the initial docking site. This indicates that serpin inhibition involves reactive center cleavage followed by full loop insertion, whereby the covalently linked protease is translocated from one pole of the inhibitor to the opposite one.
To search for molecular determinants that could be responsible for conversion of PAI-1 to the latent form, we studied the conformation of the RCL in active PAI-1 in solution. Intramolecular distance measurements by DDEM, the newly a developed method based on probe quenching and biochemical methods revealed that the RCL in PAI-1 is located much closer to the core of PAI-1 than has been suggested by the recently resolved X-ray structures of stable PAI-1 mutants, and it can be partially inserted. This possibly explains for the ability of PAI-1 to convert spontaneously to its latent form.
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Hägglöf, Peter. "Plasminogen activator inhibitor type-1 : structure-function studies and its use as a reference for intramolecular distance measurements /." Umeå : Umeå University, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-177.
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Marshall, Charlene. "Minimalist versus conventional running shoes : effects on lower limb injury incidence, pain and muscle function experienced distance runners." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/3019.
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Includes abstract.Includes bibliographical references.
The aim of this randomised clinical trial over 12 weeks was to determine if the gradual transition (accompanied by calf muscle training), from conventional to minimalist running shoes 1) increased the risk of lower limb pain or injury and 2) improved lower limb muscle function (endurance, flexibility and power) in experienced distance runners. In addition, the effects of the transition on runner satisfaction were studied. To determine whether there were significant differences in lower limb injury incidence and pain, calf endurance, lower limb muscle flexibility, lower limb muscle power, footposture index, hallux ROM and participants’ satisfaction with the type of running shoes and performance between an experimental group, that ran in minimalist shoes, and a control group that ran in conventional shoes. (b) To determine whether there were significant differences in lower limb injury incidence and pain, calf endurance, lower limb muscle flexibility, lower limb muscle power, foot posture index, hallux ROM and participants’ satisfaction with the type of running shoes and performance between groups over time.
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Akyol, Halime Iclal. "Blind Deconvolution Techniques In Identifying Fmri Based Brain Activation." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613869/index.pdf.
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In this thesis, we conduct functional Magnetic Resonance Imaging (fMRI) data analysis with the aim of grouping the brain voxels depending on their responsiveness to a neural task. We mathematically treat the fMRI signals as the convolution of the neural stimulus with the hemodynamic response function (HRF). We first estimate a time series including HRFs for each of the observed fMRI signals from a given set and we cluster them in order to identify the groups of brain voxels. The HRF estimation problem is studied within the Bayesian framework through a blind deconvolution algorithm using MAP approach under completely unsupervised and model-free settings, i.e, stimulus is assumed to be unknown and also no particular shape is assumed for the HRF. Only using a given fMRI signal together with a weak Gaussian prior distribution imposed on HRF favoring &lsquosmoothness&rsquo
, our method successfully estimates all the components of our framework: the HRF, the stimulus and the noise process. Then, we propose to use a modified version of Hausdorff distance to detect similarities within the space of HRFs, spectrally transform the data using Laplacian Eigenmaps and finally cluster them through EM clustering. According to our simulations, our method proves to be robust to lag, sampling jitter, quadratic drift and AWGN (Additive White Gaussian Noise). In particular, we obtained 100% sensitivity and specificity in terms of detecting active and passive voxels in our real data experiments. To conclude with, we propose a new framework for a mathematical treatment for voxel-based fMRI data analysis and our findings show that even when the HRF is unpredictable due to variability in cognitive processes, one can still obtain very high quality activation detection through the method proposed in this thesis.
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Bengtsson, Morgan. "Indoor 3D Mapping using Kinect." Thesis, Linköpings universitet, Datorseende, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-106145.
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In recent years several depth cameras have emerged on the consumer market, creating many interesting possibilities forboth professional and recreational usage. One example of such a camera is the Microsoft Kinect sensor originally usedwith the Microsoft Xbox 360 game console. In this master thesis a system is presented that utilizes this device in order to create an as accurate as possible 3D reconstruction of an indoor environment. The major novelty of the presented system is the data structure based on signed distance fields and voxel octrees used to represent the observed environment.Under de senaste åren har flera olika avståndskameror lanserats på konsumentmarkanden. Detta har skapat många intressanta applikationer både i professionella system samt för underhållningssyfte. Ett exempel på en sådan kamera är Microsoft Kinect som utvecklades för Microsofts spelkonsol Xbox 360. I detta examensarbete presenteras ett system som använder Kinect för att skapa en så exakt rekonstruktion i 3D av en innomhusmiljö som möjligt. Den främsta innovationen i systemet är en datastruktur baserad på signed distance fields (SDF) och octrees, vilket används för att representera den rekonstruerade miljön.
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Howell, Gareth. "Normalised distance function considered over the partition of the unit interval generated by the points of the Farey tree." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55096/.
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Kim, Nak-Kyoon. "Metal dependent structure, dynamics, and function in RNA measured by site-directed spin labeling and EPR spectroscopy." Diss., Texas A&M University, 2005. http://hdl.handle.net/1969.1/4900.
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The structure and function of RNA molecules are dependent on RNA-metal ion interactions in both diffusive and direct ways. Structural information for RNA has been obtained using various biophysical and biochemical methods. In this study, using site-directed spin labeling (SDSL) and EPR spectroscopy, distances in RNA duplexes, TAR RNA, and the hammerhead ribozyme have been measured to investigate RNA structures. Kinetic measurements have been performed in the extended hammerhead ribozyme to correlate the catalytic function with metal dependent ribozyme folding. As a basic model system for distance measurements, inter-spin distances in RNA duplexes with spin labels at various positions are measured using SDSL with continuous EPR and a Fourier deconvolution method. Divalent metal-ion dependent TAR RNA folding from bent to extended conformers is monitored by measuring inter-spin distances near the bulge region. In order to investigate a proposed loop-loop interaction in the extended hammerhead ribozyme which significantly enhances the ribozyme activity, distance measurements, dynamics studies, and kinetics measurements have been performed. We have introduced PELDOR long-distance measurements in order to investigate metal dependent folding of the hammerhead ribozyme. The dynamics of the spin labels attached to the hammerhead ribozyme with increasing mono- and divalent metal ion concentrations are monitored using CW EPR spectroscopy at room temperature. EPR data show that a loop-loop interaction occurs near the U1.6 nucleotide, and that in 0.1 M NaCl the docking occurs at submillimolar Mg2+ concentrations ([Mg2+]1/2, docking = ~ 0.7 mM). Kinetics measurements show that the hammerhead ribozyme requires high concentration of Mg2+ for the maximum cleavage activity ([Mg2+]1/2, cleavage = ~ 90 mM).
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Kennedy, Kristen. "Fynbos connectivity as a function of dispersal distance and the implications for bird conservation in the greater Cape Town area." Bachelor's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/14251.
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Connectivity is defined as the degree to which a landscape facilitates an organisms' movement. It is considered a vital element of landscape structure with key implications for metapopulation survival and ecological processes such as pollination. The connectivity of a landscape changes depending on an organisms' ability to move between patches of favourable habitat and this in turn is related to the dispersal ability of the organism. Connectivity thus changes with the scale at which the landscape is viewed; however the relationship between connectivity and dispersal ability is overlooked in many studies. This study looks at the connectivity of two types of fynbos: Highland fynbos (Thicket, Bushland, Bushclumps and High fynbos) which makes up 22.7%, and Lowland fynbos (Shrubland and Low Fynbos) which makes up 28% of the studied extent. These vegetation types are outlined by the National Land Cover Database (NLCD 2000) and analysed as a function of organism dispersal ability in the greater Cape Town area. It is shown that a relationship between dispersal ability and connectivity exists; however the relationship is not linear but sigmoidal with inflection points at 45% connectivity. This raises the question of a connectivity threshold in the Fynbos Biome. Characteristics of the landscape are assessed and it is shown that Fynbos vegetation in the greater Cape Town area is highly fragmented. Fragmentation and habitat loss decrease connectivity and are thus important factors in conservation. In order to simulate the effect of further fragmentation through habitat loss, patches of increasing size were removed and the results put into context for conservation of both the vegetation types and the dispersing organisms dependent on them. The importance of conserving patches of remnant vegetation in order to facilitate organism dispersal is highlighted by this study.
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Sun, Chunyi. "Ergonomic and Time Cost of One-Handed Lifting tasks as a Function of Shelf Height, Item Weight and Walking Distance." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1566123193772717.
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Zocher, Maria Teresa, Jos J. Rozema, Nicole Oertel, Jens Dawczynski, Peter Wiedemann, and Franziska G. Rauscher. "Biometry and visual function of a healthy cohort in Leipzig, Germany." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-205179.
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Background: Cross-sectional survey of ocular biometry and visual function in healthy eyes across the life span of a German population aged 20 to 69 years (n = 218). Subject number in percent per age category reflected the percentage within the respective age band of the population of Leipzig, Germany. Methods: Measurements obtained: subjective and objective refraction, best-corrected visual acuity, accommodation, contrast sensitivity, topography and pachymetry with Scheimpflug camera, axial length with non-contact partial coherence interferometry, and spectral-domain optical coherence tomography of the retina. Pearson correlation coefficients with corresponding p-values were given to present interrelationships between stature, biometric and
refractive parameters or their associations with age. Two-sample T-tests were used to calculate gender differences. The area under the logarithmic contrast sensitivity function (AULCSF) was calculated for the analysis of contrast sensitivity as a single figure across a range of spatial frequencies. Results: The results of axial length (AL), anterior chamber depth (ACD) and anterior chamber volume (ACV) differed as a function of the age of the participants (rho (p value): AL −0.19 (0.006), ACD −0.56 (< 0.001), ACV-0.52 (< 0.001)). Longer eyes had deeper ACD (AL:ACD 0.62 (< 0.001), greater ACV (AL:ACV 0.65 (< 0.001) and steeper corneal radii (AL:R1ant; R2ant; R1post; R2post 0.40; 0.35; 0.36; 0.36 (all with (< 0.001)). Spherical equivalent was associated with age (towards hyperopia: 0.34 (< 0.001)), AL (−0.66 (< 0.001)), ACD (−0.52 (< 0.001)) and ACV (−0.46 (< 0.001)). Accommodation was found lower for older subjects (negative association with age, r = −0.82 (< 0.001)) and contrast sensitivity presented with smaller values for older ages (AULCSF −0.38, (< 0.001)), no change of retinal thickness with age. 58 % of the study cohort presented with a change of refractive correction above ±0.50 D in one or both eyes (64 % of these were habitual spectacle wearers), need for improvement was present in the young age-group and for older subjects with increasing age. Conclusion: Biometrical data of healthy German eyes, stratified by age, gender and refractive status, enabled cross-comparison of all parameters, providing an important reference database for future patient-based research and specific in-depth investigations of biometric data in epidemiological research. Trial registration: ClinicalTrials.gov # NCT01173614 July 28, 2010
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Tsvigu, Chipo. "Students' experiences, learning styles and understanding of certain calculus concepts: A case of distance learning at the Zimbabwe open University." Thesis, University of the Western Cape, 2007. http://hdl.handle.net/11394/8480.
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Philosophiae Doctor - PhDThis study attempts to understand how distance education practices influence the learning of calculus. Understanding student learning in a distance education environment is an important factor to consider in improving the learning experiences of those students who for one reason or the other opt not to study in conventional institutions of higher education. On one hand, understanding student learning may illuminate the influences that the learning environment has on student learning and on the other hand, it may inform on how learning experiences can be improved. The aim of this study is to acquire a deeper understanding of the diverse manner in which distance students learn calculus. Specific focus is also placed on how the distance education context of the Zimbabwe Open University (ZOU) influences student learning. The study describes a group of students' experiences of learning calculus in the ZOU distance education environment. The study also describes the students' learning styles and relates these to their mathematical understanding of certain calculus concepts. The specific content topics of "limit of function" and "derivative of function" are used to view achievement and performance, thereby indicating the distance students' mathematical understanding. The information processing learning theory is used as the theoretical framework for this study. The constructs of learning styles and mathematical understanding are used to illuminate the student's learning processes. The study used the Felder-Silverman learning styles model and Hiebert and Carpenter's notion of mathematical understanding to expound these constructs. The distance education environment of the B.Sc. Mathematics and Statistics (BSMS) programme at the ZOU provided the context of the study and an interpretive case study approach was adopted. A group of students registered in a first year first semester calculus course were studied. Data were collected from students based in four ZOU regional centres; namely Harare, Mashonaland Central, Mashonaland West, and Masvingo. These regional centres were conveniently selected for the study on the basis of proximity and accessibility. A total sample of twenty six students was involved and data for the in-depth part of the study emanated from five students who were purposively selected to participate in interviews. The interviewees were selected on the basis of their performance in a written calculus test. Data for this study were collected through use of learning journals, learning styles preference questionnaires, calculus tests and interviews. The data on students' learning experiences were predominantly qualitative in nature though supported by some quantitative data. The data on learning styles and mathematical understanding were also qualitatively analysed and presented case by case for the five interviewees. The study established that in a distance education system, the type of learning environment has the potential to influence students' learning, both positively and negatively, of which the main contributing factor is the learning support system. The study found that the learning support system provided by the institution and distance educators can have an impact on student learning. With reference to the calculus course in the BSMS programme, the study identified specific aspects where the environment facilitated or deterred learning. The study also revealed that students have varied learning style preferences, and that the learning environment has the potential to impact on students' learning styles. Since learning styles occupy a central place when it comes to improving distance learning materials, the study further explored the relationship between the constructs of learning styles and mathematical understanding. The study revealed that students' learning styles can influence the students' mathematical understanding. Improving students' learning in a distance education environment rests mainly on improving the learning materials and the support systems. A carefully designed and well supported instructional distance learning package can facilitate learning. Implications of the findings point towards the improvement of the distance teaching processes through the improvement of learning materials and the learning support systems for the BSMS distance education programme.
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Mahoney, Patricia. "Perceptions of request strategy as a function of power, social distance and imposition : a study of Brown and Levinson's theory of politeness /." Title page, contents and abstract only, 1993. http://web4.library.adelaide.edu.au/theses/09ARPS/09arpsm216.pdf.
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Lazdauskaitė, Sandra. "Klasterinės ir diskriminantinės analizės taikymai mokinių pasiekimų tyrimui." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_171114-69914.
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Nacionalinių mokinių pasiekimų tyrimo metodologija yra nuolat plėtojama. Pasitarus su Švietimo plėtotės centro tyrimo skyriaus darbuotojais, buvo nuspręsta įsigilinti į klasterinės ir diskriminantinės analizės metodus, jų pritaikomumą nacionalinių tyrimų rezultatų analizei. Tai įtakojo šio darbo pasirinkimą ir tikslą - susipažinti su Klasterinės ir Diskriminantinės analizės metodais, pateikti ir aptarti jų taikymo pavyzdžius. Darbe išnagrinėti du daugiamačiai statistiniai metodai: klasterinė ir diskriminantinė analizė. Yra aptarti šių metodų teoriniai aspektai bei pateikti originalūs šių metodų pritaikymo mokinių pasiekimų tyrimams pavyzdžiai. Padarytos išvados apie šių metodų pritaikomumą nacionalinių mokinių pasiekimų tyrimo analizei atlikti.National research of student marches are continually evolving. With Educational evolve center’s help I decided to analyse Cluster and Disckriminant analysis methods and how they can be used in National research analysis. This was a reason of my work purpose - to have a look at Cluster and Disckriminant analysis methods, to offer examples of practical use. There are two statistical multidimensional methods discussed in this work (Cluster and Disckriminant analysis). There are discussed theoretical side of these methods, also you can find original examples of practical use. In conclusion I discuss about practical use of these methods in national research of student marches.
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Mustapha, Sami. "Sous-ellipticité, interpolation réelle et calcul de Weyl-Hormander." Paris 6, 1994. http://www.theses.fr/1994PA066205.
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Cette these est constituee de quatre articles et d'une note consacres a la sous-ellipticite ; au calcul s(m,g), aux distances sous-elliptiques et a l'interpolation reelle. Le but de cette these est double: en premier lieu introduire et etudier une notion de sous-ellipticite adaptee au cadre du calcul de weyl-hormander. Les techniques utilisees sont basees sur l'interpolation reelle et les techniques de semi-groupe et conduisent a une bonne generalisation des resultats classiques. Le second objectif de cette these est l'investigation de la conjecture suivante: soient deux operateurs differentiels, sous-elliptiques du second ordre a,b et soient d et les distances qui leurs correspondent, alors il est naturel de conjecturer l'equivalence des estimations d# #b et b#b a#. Les methodes developpees dans cette these permettent d'obtenir de nouveaux resultats concernant cette conjecture
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Générau, François. "Sur une approximation variationnelle stable du cut locus, et un problème isopérimetrique non local." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALM014.
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Cette thèse comporte deux parties. Dans la première partie, nous étudions une généralisation du problème variationnel de torsion élastique-plastique à des variétés. Nous montrons que dans le cas des variétés, le problème n'est pas équivalent à un problème d'obstacle, contrairement au cas euclidien, mais nous établissons l'équivalence lorsque le paramètre du problème tend vers l'infini. Nous montrons, comme dans le cas euclidien, que l'ensemble de non contact contient le cut locus de la variété, et converge vers ce dernier au sens de Hausforff. Nous montrons de plus que les miniseurs du problème sont uniformément semiconcaves. Nous en déduisons une approximation stable de cut locus, dans l'esprit du lambda axe médian de Chazal et Lieutier. Nous utilisons ensuite ce résultat pour calculer numériquement le cut locus de surfaces de géométries variées.Dans la seconde partie, nous étudions une extension d'un problème isopérimétrique non local. Précisément, on adjoint un potentiel de confinement au modèle de goutte liquide du noyau de Gamow. Nous étudions alors les minimiseurs de grand volume. Nous montrons que pour certains jeux de paramètres, les minimiseurs de grand volume convergent vers des boules, voire sont exactement des boules. Nous développons ensuite une méthode numérique pour ce problème variationnel. Cela permet de confirmer numériquement une conjecture de Choksi et Peletier en dimension 2 : dans ce cas les minimiseurs du modèle de Gamow semble être des boules si ils existentThis thesis is composed of two parts. In the first part, we study a generalization of the variational problem of elastic-plastic torsion problem to manifolds. We show that in the case of manifolds, the problem is not equivalent to an obstacle type problem, contrary to the euclidean case, but we establish the equivalence when the parameter of the problem goes to infinity. We show, as in the euclidean case, that the non contact set contains the cut locus of the manifold, and converges to the latter in the Hausdorff sense. What is more, we show that the minimizers of the problem are uniformly semiconcave. We deduce a stable approximation of the cut locus, in the spirit of the lambda medial axis of Chazal and Lieutier. We then use this result to compute numerically the cut locus of some surfaces of varied geometries.In the second part, we study an extension of a nonlocal isoperimetric problem. More precisely, we add a confinement potential to Gamow's liquid drop model for the nucleus. We then study large volume minimizers. We show that for certain sets of parameters, large volume minimizers converge to the ball, or may even exactly be the ball. Moreover, we develop a numerical method for this variational problem. Our results confirm numerically a conjecture of Choksi and Peletier, in dimension 2: it seems that minimizers of Gamow'sliquid drop model are balls as long as they exist
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Boudjlida, Khaled. "Méthodes d’optimisation numérique pour le calcul de stabilité thermodynamique des phases." Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3025/document.
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La modélisation des équilibres thermodynamiques entre phases est essentielle pour le génie des procédés et le génie pétrolier. L’analyse de la stabilité des phases est un problème de la plus haute importance parmi les calculs d’équilibre des phases. Le calcul de stabilité décide si un système se présente dans un état monophasique ou multiphasique ; si le système se sépare en deux ou plusieurs phases, les résultats du calcul de stabilité fournissent une initialisation de qualité pour les calculs de flash (Michelsen, 1982b), et permettent la validation des résultats des calculs de flash multiphasique. Le problème de la stabilité des phases est résolu par une minimisation sans contraintes de la fonction distance au plan tangent à la surface de l’énergie libre de Gibbs (« tangent plane distance », ou TPD). Une phase est considérée comme étant thermodynamiquement stable si la fonction TPD est non- négative pour tous les points stationnaires, tandis qu’une valeur négative indique une phase thermodynamiquement instable. La surface TPD dans l’espace compositionnel est non- convexe et peut être hautement non linéaire, ce qui fait que les calculs de stabilité peuvent être extrêmement difficiles pour certaines conditions, notamment aux voisinages des singularités. On distingue deux types de singularités : (i) au lieu de la limite du test de stabilité (stability test limit locus, ou STLL), et ii) à la spinodale (la limite intrinsèque de la stabilité thermodynamique). Du point de vue géométrique, la surface TPD présente un point selle, correspondant à une solution non triviale (à la STLL) ou triviale (à la spinodale). Dans le voisinage de ces singularités, le nombre d’itérations de toute méthode de minimisation augmente dramatiquement et la divergence peut survenir. Cet inconvénient est bien plus sévère pour la STLL que pour la spinodale. Le présent mémoire est structuré sur trois grandes lignes : (i) après la présentation du critère du plan tangent à la surface de l’énergie libre de Gibbs, plusieurs solutions itératives (gradient et méthodes d’accélération de la convergence, méthodes de second ordre de Newton et méthodes quasi- Newton), du problème de la stabilité des phases sont présentées et analysées, surtout du point de vue de leurs comportement près des singularités; (ii) Suivant l’analyse des valeurs propres, du conditionnement de la matrice Hessienne et de l’échelle du problème, ainsi que la représentation de la surface de la fonction TPD, la résolution du calcul de la stabilité des phases par la minimisation des fonctions coût modifiées est adoptée. Ces fonctions « coût » sont choisies de telle sorte que tout point stationnaire (y compris les points selle) de la fonction TPD soit converti en minimum global; la Hessienne à la STLL est dans ce cas positif définie, et non indéfinie, ce qui mène a une amélioration des propriétés de convergence, comme montré par plusieurs exemples pour des mélanges représentatifs, synthétiques et naturels. Finalement, (iii) les calculs de stabilité sont menés par une méthode d’optimisation globale, dite de Tunneling. La méthode de Tunneling consiste à détruire (en plaçant un pôle) les minima déjà trouvés par une méthode de minimisation locale, et a tunneliser pour trouver un point situé dans une autre vallée de la surface de la fonction coût qui contient un minimum 9 à une valeur plus petite de la fonction coût; le processus continue jusqu'à ce que les critères du minimum global soient remplis. Plusieurs exemples soigneusement choisis montrent la robustesse et l’efficacité de la méthode de Tunneling pour la minimisation de la fonction TPD, ainsi que pour la minimisation des fonctions coût modifiéesThe thermodynamic phase equilibrium modelling is an essential issue for petroleum and process engineering. Phase stability analysis is a highly important problem among phase equilibrium calculations. The stability computation establishes whether a given mixture is in one or several phases. If a mixture splits into two or more phases, the stability calculations provide valuables initialisation sets for the flash calculations, and allow the validation of multiphase flash calculations. The phase stability problem is solved as an unconstrained minimisation of the tangent plan distance (TPD) function to the Gibbs free energy surface. A phase is thermodynamically stable if the TPD function is non-negative at all its stationary points, while a negative value indicates an unstable case. The TPD surface is non-convex and may be highly non-linear in the compositional space; for this reason, phase stability calculation may be extremely difficult for certain conditions, mainly within the vicinity of singularities. One can distinguish two types of singularities: (i) the stability test limit locus (STLL), and (ii) the intrinsic limit of stability (spinodal). Geometrically, the TPD surface exhibits a saddle point, corresponding to a non-trivial (at the STLL) or trivial solution (at the spinodal). In the immediate vicinity of these singularities, the number of iterations of all minimisation methods increases dramatically, and divergence could occur. This inconvenient is more severe for the STLL than for the spinodal. The work presented herein is structured as follow: (i) after the introduction to the concept of tangent plan distance to the Gibbs free energy surface, several iterative methods (gradient, acceleration methods, second-order Newton and quasi-Newton) are presented, and their behaviour analysed, especially near singularities. (ii) following the analysis of Hessian matrix eigenvalues and conditioning, of problem scaling, as well as of the TPD surface representation, the solution of phase stability computation using modified objective functions is adopted. The latter are chosen in such a manner that any stationary point of the TPD function becomes a global minimum of the modified function; at the STLL, the Hessian matrix is no more indefinite, but positive definite. This leads to a better scheme of convergence as will be shown in various examples for synthetic and naturally occurring mixtures. Finally, (iii) the so-called Tunneling global optimization method is used for the stability analysis. This method consists in destroying the minima already found (by placing poles), and to tunnel to another valley of the modified objective function to find a new minimum with a smaller value of the objective function. The process is resumed when criteria for the global minimum are fulfilled. Several carefully chosen examples demonstrate the robustness and the efficiency of the Tunneling method to minimize the TPD function, as well as the modified objective functions
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Rolo, Roberto Mentzingen. "Modelagem geológica implícita com funções distância assinaladas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/163406.
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Previamente à cada estimativa ou simulação geoestatística os domínios geológicos do depósito devem ser modelados, o que tradicionalmente é feito de forma manual por um geomodelador, em um processo laborioso, demorado e subjetivo. Por essa razão novas técnicas conhecidas como métodos implícitos veem surgindo. Essas técnicas fornecem algoritmos que substituem o processo de digitalização manual dos métodos explícitos por alguma forma de procedimento automático. Essa dissertação visita alguns métodos implícitos bem estabelecidos com atenção especial à modelagem geológica implícita com funções distância assinalada. Um estudo de caso em um banco de dados real é apresentado e a aplicabilidade do método discutida. Embora não substitua por completo um geomodelador experiente, o método provou ser capaz de gerar modelos geológicos semi-automáticos realistas a partir dos dados amostrais, e se mostra útil principalmente nas fases iniciais da pesquisa mineral.Prior to every geostatistical estimation or simulation study there is a need for delimiting the geologic domains of the deposit, which is traditionally done manually by a geomodeler in a laborious, time consuming and subjective process. For this reason, novel techniques referred to as implicit modelling have appeared. These techniques provide algorithms that replace the manual digitization process of the traditional methods by some form of automatic procedure. This dissertation covers a few well established implicit methods currently available with special attention to the signed distance function methodology. A case study based on a real dataset was performed and its applicability discussed. Although it did not replace an experienced geomodeler, the method proved to be capable in creating semi-automatic geological models from the sampling data, especially in the early stages of exploration.
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Hatta, Ichiro, Susumu Okazaki, Kimiko Oono, and Yoshimichi Andoh. "A molecular dynamics study of the lateral free energy profile of a pair of cholesterol molecules as a function of their distance in phospholipid bilayers." AIP Publishing, 2012. http://hdl.handle.net/2237/20839.
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Grierson, Greg Michael Jr. "Analysis of Amur honeysuckle Stem Density as a Function of Spatial Clustering, Horizontal Distance from Streams, Trails, and Elevation in Riparian Forests, Greene County, Ohio." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1621942350540022.
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Benyamine, Charif Abdallah. "Sections finies d'inégalités multiplicatives de Hilbert et multiplicateurs de l'espace de Dirichlet." Thesis, Bordeaux, 2022. http://www.theses.fr/2022BORD0187.
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Nous étudions deux problèmes. Le premier concerne les sections finies de l'inégalité multiplicative de Hilbert. Nous donnons le comportement asymptotique de la meilleure constante $lambda_n$ dans l'inégalité$$Big|sum_{i,j=2}^{n}frac{a_ioverline{a_j}}{ijlog(ij)}Big|leq lambda_n sum_{i=2}^n|a_i|^2.$$Nous donnons aussi le comportement asymptotique de la version $ell^p$ des sections finies de l'inégalité multiplicative de Hilbert.Le deuxième problème concerne l'appartenance des fonctions distance à l'algèbre des multiplicateurs de l'espace de Dirichlet. Les fonctions distance sont les fonctions extérieures dont les valeurs au bord ne dépendent que de la distance par rapport à un ensemble fermé du cercle unité de mesure nulle. Nous donnons une estimation de l'intégrale de Dirichlet d'une fonction distance pour qu'elle appartienne à l'algèbre des multiplicateursWe study two problems. The first one concerns finite sections of the Hilbert multiplicative inequality. We give the asymptotic behaviour of the best constant $lambda_n$ in the inequality$$Big|sum_{i,j=2}^{n}frac{a_ioverline{a_j}}{ijlog(ij)}Big|leq lambda_n sum_{i=2}^n|a_i|^2.$$We also give the asymptotic behaviour of the $ell^p$ version of the finite sections of the Hilbert multiplicative inequality.The second problem concerns the membership of the multiplier algebra of the Dirichlet space of so-called distance functions, namely outer functions whose boundary values depend only on distance to a closed subset of measure zero. We establish an estimate for the Dirichlet integral of such function to belong to the multiplier algebras of the Dirichlet space
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Kishore, Nanad, and Ramesh Chandra. "An apt perspective of analysis." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-80375.
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Ribeiro, Luis Otoni Meireles. "Planejamento e gestão de um centro de educação a distância (CEAD) voltado para educação profissional e tecnológica : um estudo de caso." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/17243.
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Este trabalho estuda os requisitos técnicos e operacionais para que um gestor de um Centro de Educação a Distância (CEAD), em seus estágios iniciais de implantação e estruturação, possa planejar e organizar suas atividades e fundamentar a decisão de seu planejamento estratégico, em particular aquelas relacionadas às diversas equipes multidisciplinares que compõem o setor. Trata-se de um estudo interdisciplinar, que agrega as contribuições das áreas de informática na educação, ensino a distância, educação profissional e tecnológica e gestão da qualidade, a partir de uma visão sistêmica de todos os elementos que constituem a educação a distância. Foi realizada pesquisa exploratória, tomando-se como estudo de caso as atividades de planejamento e implantação de um CEAD, em uma instituição de ensino superior, com vocação consolidada na educação profissional e tecnológica. Utilizou-se o método de Desdobramento da Função Qualidade (QFD) como ferramenta para extrair as demandas de qualidade esperadas dos produtos e serviços ofertados, na visão dos clientes internos - equipes multidisciplinares - do CEAD.This work studies the technical and operational requirements related to a center of distance education, in its early foundations, in order to improve management and strategic decision, particularly the ones related to the multidisciplinary teams that compose this sector. It is an interdisciplinary study, which aggregate the contribution of informatic in education, distance education, technological and professional education and quality management, for a systemic approach of all elements that constitute the distance education. It is presented an exploratory research, based in case study about activities of planning and implant of CEAD, in a college, acknowledged in technological and professional education. The Quality Function Deployment (QFD) method was applied to extract products and services quality requirements, through the eyes of internal clients - multidisciplinary teams - of the CEAD.
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Danijela, Karaklić. "Prostori sa fazi rastojanjem i primena u obradi slike." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110710&source=NDLTD&language=en.
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Merenje kvaliteta slike korišćenjem indeksa za kvalitet slike, ne mora da odražava i praktični kvalitet slike, odnosno nije baziran na HVS (Human visual system) modelu. Formiranje razmatranih funkcija, koje se koriste u algoritmu filtriranja za određivanje rastojanja među pikselima, može se vršiti na različite načine, što se može videti u radovima iz oblasti filtriranja slike, daje širok spektar mogućnosti da se ispita uticaj fazi rastojanja npr. fazi T-metrike ili fazi Ѕ-metrike mogu imati na sam proces filtriranja slike. Cilj je poboljšanje kvaliteta slike u odnosu na medijanski filter. U okviru teorijskih razmatranja prostora sa fazi rastojanjem dobijeni su i rezultati iz teorije nepokretne tačke koji pružaju mogućnost dalje primene ovih prostora u tehnici.Measuring the image quality using a given image quality index does not necessarily reflect the practical quality of the image, that is, it is not based on the HVS (Human Visual System) model. The formation of given functions, which are used in the filtering algorithm for determining the distance between the pixels, can be done in different ways, which can be seen in works in the field of image filtering, provides a wide range of possibilities to examine the effect of fuzzy distance, for example, of the fuzzy T-metric or the fuzzy S-metric can have on the image filtering process itself. The goal is to improve image quality in relation to a vector median filter. Within the theoretical considerations of space with fuzzy distance, results from the fixed point theory have been obtained which provide the possibility of further application of these spaces in the technique.
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Skočdopol, Petr. "Hodnocení a rozklad efektivnosti pomocí Malmquistova výkonnostního indexu." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-72102.
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At first, the basics of microeconomics from the perspective of companies, effectiveness and methods of its measurement and the most important information on the distance function this thesis, are shown. It also contains the development of the Malmquist productivity index. The aim of this work is the description of this index and its components. Indicate how these values are calculated and what expressed. Secondary objectives are to introduce different variants of Malmquist indexes and their use. Four models are used for calculating individual components of the Malmquist productivity index. These are the DEA models, Aigner-Chu, Stochastic production frontiers and Stochastic activity analysis. The first three in this work are described in detail. In conclusion is an illustrative example of calculation Malmquist productivity index using DEA models. For the calculation I used the program Lingo.
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Paduru, Anirudh. "Fast Algorithm for Modeling of Rain Events in Weather Radar Imagery." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/1097.
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Weather radar imagery is important for several remote sensing applications including tracking of storm fronts and radar echo classification. In particular, tracking of precipitation events is useful for both forecasting and classification of rain/non-rain events since non-rain events usually appear to be static compared to rain events. Recent weather radar imaging-based forecasting approaches [3] consider that precipitation events can be modeled as a combination of localized functions using Radial Basis Function Neural Networks (RBFNNs). Tracking of rain events can be performed by tracking the parameters of these localized functions. The RBFNN-based techniques used in forecasting are not only computationally expensive, but also moderately effective in modeling small size precipitation events. In this thesis, an existing RBFNN technique [3] was implemented to verify its computational efficiency and forecasting effectiveness. The feasibility of modeling precipitation events using RBFNN effectively was evaluated, and several modifications to the existing technique have been proposed.
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Huang, Wei [Verfasser], Bernhard [Akademischer Betreuer] Brümmer, Thomas [Akademischer Betreuer] Glauben, Xiaohua [Akademischer Betreuer] Yu, and Matin [Akademischer Betreuer] Qaim. "Environmental Efficiency Measurement of Grassland Grazing using Stochastic Distance Function on the Qinghai-Tibetan Plateau of China / Wei Huang. Gutachter: Thomas Glauben ; Xiaohua Yu ; Matin Qaim. Betreuer: Bernhard Brümmer." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1076398693/34.
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Adetutu, Morakinyo O. "Three essays on rebound effects." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/19044.
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This thesis investigates three major aspects of energy consumption rebound effects (RE) in three papers. More specifically, the issues addressed are (i) the magnitude of economy-wide rebound effect (ii) the role of energy policy instruments in mitigating it and (iii) its channels of impact. The research begins with the estimation of cross-country economy-wide rebound effects for a panel of 55 countries over the period 1980 to 2010. A two-stage approach is utilized in which energy efficiency is first estimated from a stochastic input distance frontier (SIDF). The estimated energy efficiency is then used in a second stage dynamic panel model to derive short-run and long-run RE for an array of developing and developed countries. The cross-country point estimates indicate substantial RE magnitudes across sampled countries during the period under consideration, although a positive and encouraging finding is the declining RE trend across most of the sampled countries during the study period. The second paper contains an RE benchmark for 19 EU countries, as well as an investigation of the effects of two energy policy instruments (energy taxes and ener-gy R&D) on RE performance over the period 1995 to 2010. The results indicate that RE performance improved over the sample period, reinforcing the results from paper one. In addition, there is also some evidence suggesting that binding market-based instruments such as energy taxes have been more effective in restricting RE than in-direct instruments such as energy R&D during the period under consideration. This is consistent across both estimated model specifications. An important observation from the first essay is the slightly larger average RE across the non-OECD countries. For this reason, the last empirical chapter evaluated the channels through which RE stimulated energy use across productive sectors of major developing/emerging economies, namely Brazil, Russia, India, Indonesia and China. To achieve this, the essay relied on duality theory to decompose changes in energy demand into substitution and output effects through the estimation of a trans-log cost function using data spanning 1995-2009. Findings reveal that energy use elasticities across sampled sectors/countries are dominated by substitution effects. One intriguing result that also emerges from this analysis is the role of economies of scale and factor accumulation, rather than technical progress, in giving rise to eco-nomic growth and energy consumption in these countries during the period under consideration.
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Amir, Asgari Azadeh. "Robust Image Hash Spoofing." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12822.
Full textAbstract:
With the intensively increasing of digital media new challenges has been created for authentication and protection of digital intellectual property. A hash function extracts certain features of a multimedia object e.g. an image and maps it to a fixed string of bits. A perceptual hash function unlike normal cryptographic hash is change tolerant for image processing techniques. Perceptual hash function also referred to as robust hash, like any other algorithm is prone to errors. These errors are false negative and false positive, of which false positive error is neglected compared to false negative errors. False positive occurs when an unknown object is identified as known. In this work a new method for raising false alarms in robust hash function is devised for evaluation purposes i.e. this algorithm modifies hash key of a target image to resemble a different image’s hash key without any significant loss of quality to the modified image. This algorithm is implemented in MATLAB using block mean value based hash function and successfully reduces hamming distance between target image and modified image with a good result and without significant loss to attacked imaged quality.
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Galbany, i. Gonzàlez Lluís. "Supernova studies in the SDSS-II/SNe Survey: Spectroscopy of the peculiar SN 2007qd, and photometric properties of Type-Ia supernovae as a function of the distance to the host galaxy." Doctoral thesis, Universitat Autònoma de Barcelona, 2011. http://hdl.handle.net/10803/83974.
Full textAbstract:
Aquesta tesi engloba el treball fet durant els ultims quatre anys com a estudiant
de doctorat a l’Institut de Física d’Altes Energies (IFAE), emmarcat dins de la
col·labaració Sloan Digital Sky Survey II Supernova (SDSS-II/SNe) Survey.
Al primer capítol (§1) s’introdueixen els principals conceptes del Model Estàndar
de Cosmologia, presentant els seus orígens, les propietats dels seus continguts, i les
mesures de distància i brillantor. També es reconstrueix l’història de l’univers des del
Big Bang i es resumeixen alguns dels descobriments més excitants que han confirmat
les prediccions del Model Estàndar.
Seguidament (§2), es dona una explicació detallada de les supernoves (SNe), incloenthi
el mecanisme físic que dóna lloc a les explosions, les diferències entre els diferents
tipus, i la seva classificació espectral. També es descriuen les propietats fotomètriques i
espectroscòpiques de les supernoves de tipus Ia. Tot seguit, es resumeixen les mesures
del ritme d’explosions, les propietats de les gal·làxies on resideixen les supernoves, i
el seu ús en Cosmologia a través del diagrama de Hubble.
Al següent capítol, (§3) es descriu la col·laboració SDSS-II/SNe Survey, una extensió
de tres anys (2005-2007) del projecte Sloan (SDSS) que ha detectat i mesurat corbes
de llum de centenars de supernoves tot escanejant el cel en repetides ocasions.
Vam contribuir al seguiment espectroscòpic de les supernoves de SDSS-II/SNe,
obtenint 23 espectres de supernoves durant 4 nits d’Octubre i Novembre (5-6 Oct. i 4-5
Nov.) del 2007, utilitzant el Telescopio Nazionale Galileo (TNG) situat a l’Observatorio
del Roque de Los Muchachos (ORM) a l’illa de La Palma. Al capítol §4 es descriu tot
el procés de reducció de les dades, des de l’adquisició de les imatges fins als espectres
calibrats en flux i longitud d’ona.
A continuació de la reducció dels espectres, al capítol §5, s’analitza una de les
supernoves de tipus Ia menys lluminoses mai conegudes, la peculiar 2007qd, per la
qual vam mesurar el primer espectre. Les propietats observades de la 2007qd la situen
a la subclasse anomenada 2002cx, com a membre intermig entre la 2002cx i la 2008ha,
enllaçant aquetes. Es presenten les observacions espectroscòpiques i fotomètriques
de la supernova 2007qd i es comparen les seves propietats peculiars amb un ventall
d’altres supernoves. Aquest anàlisi va ser publicat a McClelland et al. (2010).
Al capítol §6, s’utilitzen les supernoves Ia descobertes pel SDSS-II/SNe Survey durant
els tres anys d’activitat, per buscar dependències entre les propietats fotomètriques
de les supernoves Ia i la projecció de la distància fins al centre de la gal·làxia on
resideixen, utilitzant la distància com a aproximació a les propietats locals de les
gal·làxies (ritme de creació d’estrelles, metalicitat local, etc.). Trobem que l’excés de
color de les supernoves, parametritzat per AV a MLCS2k2 i per c a SALT2 decreix
amb la distància projectada, en particular per les gal·làxies espirals. A més, amb
menys significància, també es troba que l’amplada de la corba de llum, obtinguda
amb MLCS2k2, està correlacionada amb la separació entre la supernova i el centre de
la gal·làxia per les el·líptiques, així les supernoves amb corbes de llum més estretes,
per tant menys lluminoses, s’observen més aviat a més distància del centre gal·làctic.
Aquest anàlisi va ser presentat a la conferència Supernovae and their Host Galaxies que
es va fer al Juny del 2011 a Sydney, i serà publicat a Galbany et al. (2011).
Finalment, al capítol §7, es resumeix i es donen les conclusions d’aquesta tesi.Esta tesis engloba el trabajo realizado durante los últimos cuatro años como estudiante de doctorado en el Institut de Física d’Altes Energies (IFAE), enmarcardo en la colabaración Sloan Digital Sky Survey II Supernova (SDSS-II/SNe) Survey. En el primer capítulo (§1) se introducen los principales conceptos del Modelo Estándar de Cosmología, presentando sus orígenes, las propiedades de sus contenidos, y las medidas de distancia y brillo. También se reconstruyen la historia del universo desde el Big Bang y se resumen algunos de los descubrimientos más excitantes que han confirmado las predicciones del Modelo Estándar. Seguidamente (§2), se da una explicación detallada de las supernovas (SNe), incluyendo el mecanismo físico que da lugar a las explosiones, las diferencias entre los diferentes tipos, y su clasificación espectral. También se describen las propiedades fotomètricas y espectroscópicas de las supernovas de tipo Ia. A continuación, se resumen las medidas del ritmo de explosión, las propiedades de las galaxias donde residen las supernovas, y su uso en Cosmología a través del diagrama de Hubble. En el siguiente capítulo, (§3) se describe SDSS-II/SNe Survey, una extensión de tres años (2005-2007) del proyecto Sloan (SDSS) que ha detectado y medido curvas de luz para centenares de supernovas a través de escanear el cielo en repetidas ocasiones. Como parte del seguimiento espectroscópico de las supernova de SDSS-II/SNe, contribuímos obteniendo 23 espectros de supernovas durante 4 noches de Octubre y Noviembre (5-6 Oct. y 4-5 Nov.) del 2007, utilizando el Telescopio Nazionale Galileo (TNG) situado en el Observatorio del Roque de Los Muchachos (ORM) en La Palma. En el capítulo §4 se describe toda la reducción de datos, desde la adquisición de las imágenes hasta los espectros calibrados en flujo y longitud de onda. Siguiendo la reducción de los espectros, en el capítulo §5, se describe una de las supernovas de tipo Ia menos luminosa jamàs conocida, la peculiar 2007qd, para la cual medimos el primer espectro. Las propiedades observadas de la 2007qd la sitúan en la subclase llamada 2002cx, como miembro intermedio entre las supernovas 2002cx y 2008ha, enlazándolas. Se presentan las observaciones espectroscópicas y fotométricas de la supernova 2007qd y se comparan su propiedades con un conjunto de otras supernovas. Éste análisis fue publicado en McClelland et al. (2010). En el capítulo §6, se utilizan las supernovas Ia descubiertas por SDSS-II/SNe Survey durante los tres años de actividad, para buscar dependencias entre las propiedades fotométricas de las supernovas Ia y la proyección de la distancia hasta el centro de la galaxia donde residen, utilizando la distancia como aproximación a las propiedades locales de las galaxias (ritmo de creación de estrellas, metalicidad local, etc.). Encontramos que el exceso de color de las supernovas, parametrizado por AV en MLCS2k2 y por c en SALT2 decrece con la distancia, en particular para las galaxias espirales. Además, y con menos significancia, también se encuentra que la amplitud de la curva de luz, obtenida con MLCS2k2, está correlacionada con la separación entre la supernova y el centro de la galaxia para las galaxias elípticas, así las supernovas con curvas de luz más estrechas, y menos luminosas, se observan a más distancia del centro galactico. Este análisis fue presentado en la conferencia Supernovae and their Host Galaxies que tuvo lugar en Junio del 2011 en Sydney, y serà publicado en Galbany et al. (2011). Finalmente, en §7, se resume y se presentan las conclusiones de esta tesis.
This thesis comprises the work I have been doing during the last four years at Institut de Física d’Altes Energies (IFAE) as a PhD student, and has to be understood within the context of the Sloan Digital Sky Survey II Supernova (SDSS-II/SNe) survey. The content of this thesis is ordered as follows. In the next Chapter (§1) I introduce the main concepts of the Standard Model of Cosmology, presenting the origins, the properties of its contents, and the distance and the brightness measurements. I also reconstruct the history of universe since the Big Bang and summarize some of the most exciting discoveries that have confirmed the Standard Model predictions. In §2, a detailed explanation of supernovae (SNe) is given, including the physical mechanism that accounts for their explosions, the differences among the several types of SNe, and their spectral classification. We also describe the spectroscopic and photometric properties of Type-Ia SNe. After that, we review the SNe rate of the explosion measurements, the properties of their host galaxies, and their use in Cosmology through the Hubble diagram. After that, in §3, I describe the SDSS-II/SNe survey, a three-year (2005-2007) extension of SDSS of which I am an external collaborator, which has detected and measured light-curves for several hundred supernovae through repeat scans of the sky. As a part of the spectroscopic follow-up of the SDSS-II/SNe candidates, we contributed to the project taking spectra of 23 SNe during four nights in October and November (5-6 Oct. and 4-5 Nov.) of 2007 using the Telescopio Nazionale Galileo (TNG) located at the Observatorio del Roque de Los Muchachos (ORM) in La Palma. In §4, the whole reduction procedure, from the acquisition of the raw data by the telescope camera to the final flux-calibrated spectra, is described. Following the spectra reduction, in §5, I describe one of the most subluminous type-Ia events known, the peculiar 2007qd supernova, for which we took the first spectrum. The observed properties of 2007qd place it in the 2002cx subclass of supernovae, specifically as a member intermediate to 2002cx and 2008ha, linking these objects. We present the photometric and spectroscopic observations of 2007qd and compare its unique properties with a range of other SNe. This work was compiled and published in McClelland et al. (2010). Then, in §6, the three-year sample of Type Ia supernovae (SNe Ia) discovered by the SDSS-II/SNe Survey is used to look for dependencies between photometric SN Ia properties and the projected distance to the host galaxy center, using the distance as a proxy for local galaxy properties (local star-formation rate, local metallicity, etc.). We find that the excess color of the SN, parametrized by AV in MLCS2k2 and by c in SALT2 decreases with the projected distance, in particular for spiral galaxies. At a lower significance we find that the light-curve width, as obtained from MLCS2k2 , is correlated with the SN-galaxy separation for elliptical hosts, so that SNe Ia with narrower light-curves, hence dimmer, are more commonly observed at large distances from the host galaxy core. This analysis was presented in the Supernovae and their Host Galaxies conference which was held at Sydney, Australia in June 2011, and will be published in Galbany et al. (2011). Finally, in §7 we give a summary and the conclusions of this thesis.
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Rundgren, Emil. "Automatic Volume Estimation of Timber from Multi-View Stereo 3D Reconstruction." Thesis, Linköpings universitet, Datorseende, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-142513.
Full textAbstract:
The ability to automatically estimate the volume of timber is becoming increasingly important within the timber industry. The large number of timber trucks arriving each day at Swedish timber terminals fortifies the need for a volume estimation performed in real-time and on-the-go as the trucks arrive. This thesis investigates if a volumetric integration of disparity maps acquired from a Multi-View Stereo (MVS) system is a suitable approach for automatic volume estimation of timber loads. As real-time execution is preferred, efforts were made to provide a scalable method. The proposed method was quantitatively evaluated on datasets containing two geometric objects of known volume. A qualitative comparison to manual volume estimates of timber loads was also made on datasets recorded at a Swedish timber terminal. The proposed method is shown to be both accurate and precise under specific circumstances. However, robustness is poor to varying weather conditions, although a more thorough evaluation of this aspect needs to be performed. The method is also parallelizable, which means that future efforts can be made to significantly decrease execution time.