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Eriksen, Niklas. "Combinatorial methods in comparative genomics." Doctoral thesis, KTH, Mathematics, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3508.
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Purvis, A. "Comparative methods : theory and practice." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315843.
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Singh, Jagmeet 1980. "Comparative analysis of robust design methods." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35630.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 161-163).
Robust parameter design is an engineering methodology intended as a cost effective approach to improve the quality of products, processes and systems. Control factors are those system parameters that can be easily controlled and manipulated. Noise factors are those system parameters that are difficult and/or costly to control and are presumed uncontrollable. Robust parameter design involves choosing optimal levels of the controllable factors in order to obtain a target or optimal response with minimal variation. Noise factors bring variability into the system, thus affecting the response. The aim is to properly choose the levels of control factors so that the process is robust or insensitive to the variation caused by noise factors. Robust parameter design methods are used to make systems more reliable and robust to incoming variations in environmental effects, manufacturing processes and customer usage patterns. However, robust design can become expensive, time consuming, and/or resource intensive. Thus research that makes robust design less resource intensive and requires less number of experimental runs is of great value. Robust design methodology can be expressed as multi-response optimization problem.
(cont.) The objective functions of the problem being: maximizing reliability and robustness of systems, minimizing the information and/or resources required for robust design methodology, and minimizing the number of experimental runs needed. This thesis discusses various noise factor strategies which aim to reduce number of experimental runs needed to improve quality of system. Compound Noise and Take-The-Best-Few Noise Factors Strategy are such noise factor strategies which reduce experimental effort needed to improve reliability of systems. Compound Noise is made by combing all the different noise factors together, irrespective of the number of noise factors. But such a noise strategy works only for the systems which show effect sparsity. To apply the Take-The-Best-Few Noise Factors Strategy most important noise factors in system's noise factor space are found. Noise factors having significant impact on system response variation are considered important. Once the important noise factors are identified, they are kept independent in the noise factor array. By selecting the few most important noise factors for a given system, run size of experiment is minimized.
(cont.) Take-The-Best-Few Noise Factors Strategy is very effective for all kinds of systems irrespective of their effect sparsity. Generally Take-The-Best-Few Noise Factors Strategy achieves nearly 80% of the possible improvement for all systems. This thesis also tries to find the influence of correlation and variance of induced noise on quality of system. For systems that do not contain any significant three-factor interactions correlation among noise factors can be neglected. Hence amount of information needed to improve the quality of systems is reduced.
by Jagmeet Singh.
Ph.D.
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Zeitler, Berndt. "A comparative study of source substitution methods." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974828165.
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Fuxelius, Hans-Henrik. "Methods and Applications in Comparative Bacterial Genomics." Doctoral thesis, Uppsala universitet, Molekylär evolution, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8398.
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Comparative studies of bacterial genomes, now counting in the hundreds, generate massive amounts of information. In order to support a systematic and efficient approach to genomic analyses, a database driven system with graphic visualization of genomic properties was developed - GenComp. The software was applied to studies of obligate intracellular bacteria. In all studies, ORFs were extracted and grouped into ORF-families. Based on gene order synteny, orthologous clusters of core genes and variable spacer ORFs were identified and extracted for alignments and computation of substitution frequencies. The software was applied to the genomes of six Chlamydia trachomatis strains to identify the most rapidly evolving genes. Five genes were chosen for genotyping, and close to a 3-fold higher discrimination capacity was achieved than that of serotypes. With GenComp as the backbone, a massive comparative analysis were performed on the variable gene set in the Rickettsiaceae, which includes Rickettsia prowazekii and Orientia tsutsugamushi, the agents of epidemic and scrub typhus, respectively. O. tsutsugamushi has the most exceptional bacterial genome identified to date; the 2.2 Mb genome is 200-fold more repeated than the 1.1 Mb R. prowazekii genome due to an extensive proliferation of conjugative type IV secretion systems and associated genes. GenComp identified 688 core genes that are conserved across 7 closely related Rickettsia genomes along with a set of 469 variably present genes with homologs in other species. The analysis indicates that up to 70% of the extensively degraded and variably present genes represent mobile genetic elements and genes putatively acquired by horizontal gene transfer. This explains the paradox of the high pseudogene load in the small Rickettsia genomes. This study demonstrates that GenComp provides an efficient system for pseudogene identification and may help distinguish genes from spurious ORFs in the many pan-genome sequencing projects going on worldwide.
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Mota, Pedro Jorge Gomes. "Comparative analysis of multicriteria decision making methods." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11263.
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Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de ComputadoresThe main objective of this dissertation is to perform a Comparative Analysis of different Multicriteria Decision Making Methods applied to real-world problems, in order to produce relevant information to enable the incorporation of those methods on computational platforms. The current document presents a simple case study concerning a decision support application targeted for a real problem regarding retrofitting alternatives of a building with energy efficiency impact. The application process was started with the selection of two Multicriteria Decision Making Methods guided by a preexisting framework, and resulted in the choice of AHP and PROMETHEE II methodologies. These two methods were then combined with three different decision maker profiles (Conservative, Moderate and Aggressive) created by means of risk assessment profiling techniques for portfolio allocation. Afterwards, the chosen decision criteria were disposed in a Risk Pyramid according to their inherent level of risk regarding project evaluation. A match was then performed between the decision maker profiles and each criterion, so as to define a proper set of weights for the decision criteria and preference functions, with corresponding preference and indifference thresholds. Finally, three different sets of results (one for each decision maker profile) were produced using appropriate software, and a Sensitivity Analysis was performed over the criteria to understand their influence on the solution. The general conclusion of this Comparative Analysis is that the increase in the preference modelling ability of the methods brings up the least expected alternatives as recommendations for the decision maker. Besides, we have concluded that the decision profiles that allocate bigger weights to the riskiest criteria are the ones that produce the more dispersed set of results within each method application and within each decision maker profile.
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Perkins, Crysta. "A Comparative Evaluation of Functional Analytic Methods." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157622/.
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The individual functional analysis (FA) is the most widely used method to identify variables that influence the occurrence of problem behavior. Researchers often modify the FA after the analysis reveals undifferentiated responding. The interview-informed synthesized contingency analysis (IISCA) is one of the most substantial variations of the FA that builds upon the FA modifications. We evaluated the use of the two different functional analytic methods, the FA and IISCA, and the subsequent function-based treatment to reduce problem behavior for three children with autism spectrum disorder (ASD). The individual FA and the IISCA demonstrated differentiated responding for all participants. The treatment based on the results from the traditional FA was effective for all children. We discuss the implications of these findings.
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Alqahtani, Abdullah Ayed F. "Comparative Analysis of Roundabout Capacity Analysis Methods." University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1557252181941848.
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Hawley, Kevin J. "A comparative analysis of areal interpolation methods." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1139949635.
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Meyer, Irmtraud Margret. "Mathematical methods for comparative Ab initio gene prediction." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619669.
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Sanna, Fausto. "Timber modern methods of construction : a comparative study." Thesis, Edinburgh Napier University, 2018. http://researchrepository.napier.ac.uk/Output/1256099.
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The doctoral research revolves around a comparative study of timber modern methods of construction for low-rise, residential buildings in Scotland. The building techniques studied involve both timber-frame panel construction (open-panel and closed-panel systems and structural insulated panels) and massive-timber construction (cross-laminated and nail-laminated timber panels). A non-timber technique is also included in the study: more traditional, load-bearing masonry (blockwork). These different building techniques have been analysed from two complementary aspects: environmental impacts and thermal performance. The environmental study is based on the life-cycle assessment methodology and embraces various aspects: environmental impacts (e.g., climate change, acidification, eutrophication, ozone depletion, etc.), consumption of energy (renewable and non-renewable resources) and production of waste (from non-hazardous to radioactive). The assessment takes a cradle-to-gate approach and, in its structure and method, is informed by the current recommendations of the international standards in the field (i.e., ISO 14040 series). Various environmental trade-offs between construction methods have been identified. In terms of global-warming potential (excluding biogenic carbon sequestration), results suggest that timber-frame buildings show a better performance than masonry buildings; this is particularly true for the open-panel system, which emits about 10% less carbon than the masonry counterpart. Massive-timber buildings tend to cause more carbon emissions than masonry ones. In terms of consumption of non-renewable primary energy, timber buildings do not generally show significant advantages with respect to blockwork-based masonry. In particular, structural-insulated panel systems tend to show very high energy requirements. Timber-based buildings show a tendency to cause increased acidification, eutrophication and creation of low ozone than their masonry counterpart. The level of offsite fabrication that is employed for the erection of the buildings plays an important role in the magnitude of most environmental impacts, which show an average decrease between 5% and 10% when some of the operations are shifted from the construction site to the factory. v The thermal study investigates the performance of the building envelope, and, in particular, of external walls, by means of tests whereby the thermal behaviour of a sample of walls (of full-size section) has been observed and measured over time. On the outside, the walls were exposed to real, natural weather variations throughout the summer. The study especially focuses on the time-dependent response of three different walling systems (which results from their individual cross-sectional arrangements of building components and the associated combination of heat-storage capacity and thermal resistance): a timber-framed wall, a cross-laminated-timber wall and a masonry wall. Thus, the main goal of the study was to characterise the thermal-inertia parameters of these walls. This type of thermal behaviour is related to the repercussions of global climate change at UK level, especially in terms of increase in solar irradiance and temperature, which requires an adaptation of the building-envelope such that it can perform well both during wintertime and summertime, by providing maximum indoor comfort with minimum economic and environmental costs from the construction and operation of buildings. The timber-framed wall possesses the greatest capacity to slow down the propagation of temperature waves from the outer surface to the inner surface (time lag), whereas the masonry wall performs best with respect to reducing the amplitude of temperature oscillation on the inner surface (decrement factor). The cross-laminated-timber wall exhibits intermediate values of both time lag and decrement factor, relative to the other two walls. Both the thermal and life-cycle assessment of the construction alternatives aim at assisting the design and decision-making process in the residential field and at suggesting areas that need to be addressed and improved, towards a coherent evolution of the building techniques included in this study and a step forward in the realisation of sustainable, low-rise dwellings.
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Aslam, Gulshan, and Faisal Farooq. "A comparative study on Traditional Software Development Methods and Agile Software Development Methods." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH. Forskningsområde Informationsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15383.
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Everyone is talking about the software development methods but these methods are categorised into the different parts and the most important are two categories, one is agile software development methods and second is using the traditional software development methods. Agile software methods are relatively considered to be quick and for the small teams. Our main mission is to check which method is better from each other, so for that purpose we go out in the software development market to meet the professional to ask about their satisfaction on these software development methods. Our research is based on to see the suitable method for the professionals; see the challenges on the adoptability of methods and which method is quicker. To perform this study we have gone through a survey questionnaire, and results are analysed by using mixed method approach. Results shows that professionals from both types of methods are satisfied but professionals with traditional methods are more satisfy with their methods with respect to development of quality software, whereas agile professionals are more satisfied with their methods with respect of better communication with their customers. With agility point of view, our study says that both methods have characteristics which support agility but not fully support, so in such case we need to customize features from both types of methodologies.
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Jamali, Hamadi. "Adaptive control methods for mechanical manipulators: a comparative study." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/26847.
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Malmgren, Christoffer. "A Comparative Study of Routing Methods in Capsule Networks." Thesis, Linköpings universitet, Datorseende, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156673.
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Recently, the deep neural network structure caps-net was proposed by Sabouret al. [11]. Capsule networks are designed to learn relative geometry betweenthe features of a layer and the features of the next layer. The Capsule network’smain building blocks are capsules, which are represented by vectors. The ideais that each capsule will represent a feature as well as traits or subfeatures ofthat feature. This allows for smart information routing. Capsules traits are usedto predict the traits of the capsules in the next layer, and information is sent toto next layer capsules on which the predictions agree. This is called routing byagreement.This thesis investigates theoretical support of new and existing routing al-gorithms as well as evaluates their performance on the MNIST [16] and CIFAR-10 [8] datasets. A variation of the dynamic routing algorithm presented in theoriginal paper [11] achieved the highest accuracy and fastest execution time.
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Desai, Unmesh Jeetendra. "Comparative Analytical Methods for the Measurment of Chlorine Dioxide." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34134.
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Four commercially available methods used for the analysis of low-level Chlorine Dioxide (ClO2) concentrations in drinking water were evaluated for accuracy and precision and ranked according to cost, efficiency and ease of the methods under several conditions that might be encountered at water treatment plants.
The different analytical methods included:
1.The DPD (N, N-diethyl-p-phenylenediamine) method
2.Lissamine Green B (LGB) wet-chemical method
3.Palintest® kit LGB
4.Amperometric titration
All these tests were performed with standard 1.0 mg/L ClO2 either alone or in the presence of different chlorine species, including chlorite ion (ClO2-, 0.5 mg/L), chlorate ion (ClO3-, 0.5 mg/L) and chlorine (Cl2, 1.0 mg/L). The tests were performed with four different matrices, with different concentrations of 0.1 mg/L ClO2, 0.5 mg/L ClO2 and 1.0 mg/L ClO2 at a constant temperature of 20oC and at different temperatures of 0oC, 10oC and 20oC at a fixed ClO2 concentration of 1.0 mg/L.
None of the four methods produced the desired level of either accuracy or precision. For all four methods, interference to the measured ClO2 concentration from the addition of ClO2-, ClO3-, and Cl2 was minimal when the methods were performed according to specifications. The Palintest® was the best all-round method because it was easy to perform, performed well at all concentrations tested, and its colored product was stable. The HACH® DPD method was also easy to perform and gave the best results when measuring concentrations of 1.0 mg/L ClO2.
The DPD method was less accurate than the Palintest® at lower concentrations. The DPD colored product that formed upon reaction of ClO2 and DPD was unstable, making it necessary to measure the intensity of the colored product at exactly 1 minute. The amperometric titration and lissamine green methods were more cumbersome and time-consuming to perform than either the DPD or Palintest® methods; for this reason they are less desirable for routine use.Master of Science
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Kelley, Edward T. II. "Comparative Analysis of Obesity Classification Methods in Aging Adults." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1429283749.
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Shenoi, Sangeetha Chandra. "A Comparative Study on Methods for Stochastic Number Generation." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1511881394773194.
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Pathak, Subrat. "A Comparative Study of Non Linear Conjugate Gradient Methods." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc283864/.
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We study the development of nonlinear conjugate gradient methods, Fletcher Reeves (FR) and Polak Ribiere (PR). FR extends the linear conjugate gradient method to nonlinear functions by incorporating two changes, for the step length αk a line search is performed and replacing the residual, rk (rk=b-Axk) by the gradient of the nonlinear objective function. The PR method is equivalent to FR method for exact line searches and when the underlying quadratic function is strongly convex. The PR method is basically a variant of FR and primarily differs from it in the choice of the parameter βk. On applying the nonlinear Rosenbrock function to the MATLAB code for the FR and the PR algorithms we observe that the performance of PR method (k=29) is far better than the FR method (k=42). But, we observe that when the MATLAB codes are applied to general nonlinear functions, specifically functions whose minimum is a large negative number not close to zero and the iterates too are large values far off from zero the PR algorithm does not perform well. This problem with the PR method persists even if we run the PR algorithm for more iterations or with an initial guess closer to the actual minimum. To improve the PR algorithm we suggest finding a better weighing parameter βk, using better line search method and/or using specific line search for certain functions and identifying specific restart criteria based on the function to be optimized.
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Kunz, Lauren Margaret. "Statistical Methods for Comparative Effectiveness Research of Medical Devices." Thesis, Harvard University, 2014. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14226082.
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A recent focus in health care policy is on comparative effectiveness of treatments--from drugs to behavioral interventions to medical devices. Medical devices bring a unique set of challenges for comparative effectiveness research. In this dissertation, I develop statistical methods for comparative effectiveness estimation and illustrate the methodology in the context of three different medical devices. In chapter 2, I review approaches for causal inference in the context of observational cohort studies, utilizing a potential outcomes framework demonstrated using data for patients undergoing revascularization surgery with radial versus femoral artery access. Propensity score methods; G-computation; augmented inverse probability of treatment weighting; and targeted maximum likelihood estimation are implemented and their causal and statistical assumptions evaluated. In chapter 3, I undertake a theoretical and simulation-based assessment of differential follow-up information per treatment arm on inference in meta-analysis where applied researchers commonly assume similar follow-up duration across treatment groups. When applied to the implantation of cardiovascular resynchronization therapies to examine comparative survival, only 3 of 8 studies report arm-specific follow-up. I derive the bias of the rate ratio for an individual study using the number of deaths and total patients per arm and show that the bias can be large, even for modest violations of the assumption that follow-up is the same in the two arms. Furthermore, when pooling multiple studies with Bayesian methods for random effects meta-analysis, the direction and magnitude of the bias is unpredictable. In chapter 4, I examine the statistical power for designing a study of devices when it is difficult to blind patients and providers, everyone wants the device, and clustering by hospitals where the devices are implanted needs to be taken into account. In these situations, a stepped wedge design (SWD) cluster randomized design may be used to rigorously assess the roll-out of novel devices. I determine the exact asymptotic theoretical power using Romberg integration over cluster random effects to calculate power in a two-treatment, binary outcome SWD. Over a range of design parameters, the exact method is from 9% to 2.4 times more efficient than designs based on the existing method.
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Gesteira, Costa Filho Ivan. "Comparative analysis of clustering methods for gene expresion data." Universidade Federal de Pernambuco, 2003. https://repositorio.ufpe.br/handle/123456789/2538.
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Previous issue date: 2003Large scale approaches, namely proteomics and transcriptomics, will play the most important role of the so-called post-genomics. These approaches allow experiments to measure the expression of thousands of genes from a cell in distinct time points. The analysis of this data can allow the the understanding of gene function and gene regulatory networks (Eisen et al., 1998). There has been a great deal of work on the computational analysis of gene expression time series, in which distinct data sets of gene expression, clustering techniques and proximity indices are used. However, the focus of most of these works are on biological results. Cluster validation has been applied in few works, but emphasis was given on the evaluation of the proposed validation methodologies (Azuaje, 2002; Lubovac et al., 2001; Yeung et al., 2001; Zhu & Zhang, 2000). As a result, there are few guidelines obtained by validity studies on which clustering methods or proximity indices are more suitable for the analysis of data from gene expression time series. Thus, this work performs a data driven comparative study of clustering methods and proximity indices used in the analysis of gene expression time series (or time courses). Five clustering methods encountered in the literature of gene expression analysis are compared: agglomerative hierarchical clustering, CLICK, dynamical clustering, k-means and self-organizing maps. In terms of proximity indices, versions of three indices are analysed: Euclidean distance, angular separation and Pearson correlation. In order to evaluate the methods, a k-fold cross-validation procedure adapted to unsupervised methods is applied. The accuracy of the results is assessed by the comparison of the partitions obtained in these experiments with gene annotation, such as protein function and series classification
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Mesclier, Évelyne. "Dynamics of the local territories: why and how to study and compare them within a globalized world." Pontificia Universidad Católica del Perú. Centro de Investigación en Geografía Aplicada, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/119664.
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Globalization is not only a transformation of the economical world, but also of geographical space in its totality. The local territories participate in this transformation. To study and compare their evolution can help us to analyze the globalisation as well as its construction, its effects and in its limits, as the existence of social and political dynamics which are not globalized. This reflexion rests on case studies in Peru, made in collaboration with other French and Peruvian researchers.La globalización no es solo una transformación del mundo económico sino también del espacio geográfico en su conjunto. Los territorios locales participan en esta transformación. Estudiar y comparar sus evoluciones nos puede ayudar a analizar tanto la globalización, en su construcción, en sus efectos y en sus límites, como la existencia de dinámicas sociales y políticas que no son globalizadas. La reflexión se fundamenta sobre casos estudiados en el Perú, en colaboración con otros investigadores franceses y peruanos.
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Murphy, Timothy J. "A comparative evaluation of liquid infiltration methods for bioreactor landfills." Connect to resource, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1086213619.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xvii, 342 p.; also includes graphics. Includes bibliographical references (p. 164-171). Available online via OhioLINK's ETD Center
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Ataie, Feraidon Farahmand. "A comparative study of strength assessment methods for RC columns." Thesis, Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4263.
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Sartaj, Majid. "Comparative study of methods of aeration for composting manure slurries." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/9842.
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Composting is a simple and economically attractive method to treat and stabilize animal waste slurries. However, a comparison of different methods of aeration for composting under high moisture content (MC) and the influence zones of the aeration pipes have not been reported in the literature. Therefore, a large scale study was conducted to investigate and compare the performance of three modes of aeration, namely natural, passive and forced aeration. A total of 9 piles, 3 replicates for each treatment, were built in trapezoidal shape with a volume of 5.03 m$\sp3$ each and monitored for a period of 90 days. Peat was used as the bulking agent. Initial MC of raw compost was 76%. A total of 233 thermocouples were built and installed in the compost piles to monitor the temperature profiles and distribution. (Abstract shortened by UMI.)
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Palacios, Cuesta Aitor. "A comparative study of structured prediction methods for sequence labeling." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186385.
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Some machine learning tasks have a complex output, rather than a real number or a class. Those outputs are composed by elements which have interdependences and structural properties. Methods which take into account the form of the output are known as structured prediction techniques. This study focuses on those techniques, evaluating their performance for tasks of sequence labeling and comparing them. Specifically, tasks of natural language processing are used as benchmarks. The principal problem evaluated is part-of-speech tagging. Datasets of different languages (English, Spanish, Portuguese and Dutch) and environments (newspapers, twitter and chats) are used for a general analysis. Shallow parsing and named entity recognition are also examined. The algorithms treated are structured perceptron, conditional random fields, structured support vector machines and trigram hidden Markov models. They are also compared to different approaches to solve these problems. The results show that, in general, structured perceptron has the best performance for sequence labeling with the conditions evaluated. However, with few training examples, structured support vector machines can achieve a similar or superior accuracy. Moreover, the results for conditional ranom fields is near those two methods. The relative results of the algorithms are similar across different datasets, but the absolute accuracies are dependent on their specificities.
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Bhattacharya, Sutanuka. "A comparative study of different methods of predicting time series." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq25985.pdf.
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Shi, Xie-Qi. "Comparative studies of modern methods for caries detection and quantification /." Stockholm, 2001. http://diss.kib.ki.se/2001/91-628-4702-3/.
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Belton, V. "A comparative study of methods for multiple criteria decision aiding." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377201.
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Waibler, Saskia [Verfasser]. "Comparative Studies on Manufacturing Methods for Cationic Liposomes / Saskia Waibler." Aachen : Shaker, 2004. http://d-nb.info/1181603102/34.
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Chau, Eric T. F. "Comparative study of joining methods for a SMART aerospace application." Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/7033.
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The adaptive serrated nozzle (ASN) is one of the most promising concepts to help reduce the noise level generated by aero-engines. Shear between a hot air stream and ambient air at the nozzle exit creates noise. The serrated nozzle is designed to protrude into the air stream causing mixing between the two air streams reducing the noise level. Adaptive control system using shape memory alloy (SMA) actuators deploy the protrusion only when required in order to maximise fuel efficiency. The successful joining of NiTi shape memory alloy (SMA) to the titanium parent structure is critical to the development of the adaptive serrated nozzle. However, joining of SMAs to dissimilar metals is widely known as extremely difficult if not impossible. This research provides a preliminary study into the potential of using SMAs in large engineering applications such as the ASN and the development of viable joining methods for joining SMA to titanium based alloy. Five most favourable conventional joining methods were selected for experimental investigation. Results proved that the successful joining of SMA to dissimilar alloys was extremely difficult, joint failures were mainly due to the formation of brittle intermetallics at joint interfaces. The formation of these intermetallics occurs irrespective of the type of joining method and level of heat input employed. However, it has been shown that the formation of these intermetallics can be suppressed by the manipulation of the joint composition. A marked improvement in joint performance has been achieved for joints that contained no more than 25 at% nickel. Joint improvement has also been achieved through the addition of titanium at the joint, although further research is necessary to investigate the effect of titanium addition to joint performance.
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Lu, An. "Comparative assessment of several SPECT scatter correction methods using SimSPECT." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/39773.
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Walter, Klaudia. "Statistical methods for comparative genomics in the field of bioinformatics." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611909.
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Bolfarine, Henrique. "Comparative evaluation of network reconstruction methods in high dimensional settings." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/45/45133/tde-18052017-001105/.
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In the past years, several network reconstruction methods modeled as Gaussian Graphical Model in high dimensional settings where proposed. In this work we will analyze three different methods, the Graphical Lasso (GLasso), Graphical Ridge (GGMridge) and a novel method called LPC, or Local Partial Correlation. The evaluation will be performed in high dimensional data generated from different simulated random graph structures (Erdos-Renyi, Barabasi-Albert, Watts-Strogatz ), using Receiver Operating Characteristic or ROC curve. We will also apply the methods in the reconstruction of genetic co-expression network for the differentially expressed genes in cervical cancer tumors.Vários métodos tem sido propostos para a reconstrução de redes em alta dimensão, que e tratada como um Modelo Gráfico Gaussiano. Neste trabalho vamos analisar três métodos diferentes, o método Graphical Lasso (GLasso), Graphical Ridge (GGMridge) e um novo método chamado LPC, ou Correlação Parcial Local. A avaliação será realizada em dados de alta dimensão, gerados a partir de grafos aleatórios (Erdos-Renyi, Barabasi-Albert, Watts-Strogatz ), usando Receptor de Operação Característica, ou curva ROC. Aplicaremos também os metidos apresentados, na reconstrução da rede de co-expressão gênica para tumores de câncer cervical.
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Kajaste, I. (Inna). "Comparative evaluation of instruction methods for mobile fitness assessment applications." Master's thesis, University of Oulu, 2016. http://urn.fi/URN:NBN:fi:oulu-201612073209.
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This study examines the instructing of standardized physical fitness assessment in a mobile environment. The main focus of this research was to determine if the fitness tests can be performed with correct techniques with the aid of a mobile application. Different types of visual aids, instructions and mobile devices were evaluated and compared in relation to usability and prevalence of errors. A prototype of a mobile fitness assessment application, My Energy Test, was used in a 2 x 2 x 3 between-subjects user study with a total of 72 participants. Data was gathered using a postquestionnaire and recording user tests. The questionnaire measured the perceived usability, and video recordings were analyzed for deviations, i.e. errors, from the correct test techniques. Main findings show that the device used did not have an effect on the perceived usability, but influenced the quantity of errors made. Moreover, it was found that audio and text instructions were perceived with equal usability with each other. The visual aid used had a statistically significant effect on the perceived usability score with video and picture series being rated more favorably compared to animation. The best combination of least amount of errors and perceived usability was observed when either video or picture series visual aid was combined with text instructions. It was concluded that standardized physical fitness tests can be carried out with sufficient correctness without the help of a professional instructorTämä tutkimus tarkastelee standardoitujen kuntotestien ohjeistusta mobiiliympäristössä. Tutkimuksen pääpaino oli selvittää voiko kuntotestit suorittaa oikeilla tekniikoilla mobiilisovelluksen avulla. Eri visuaalisia apukeinoja, ohjeistuksia ja mobiililaitteita arvioitiin ja vertailtiin käytettävyyden ja virheiden esiintymisen suhteen. My Energy Test -kuntotestisovelluksen prototyyppiä käytettiin 2 x 2 x 3 kohteiden välisessä käyttäjätutkimuksessa, jossa oli kokonaisuudessaan 72 osallistujaa. Tietoa kerättiin kyselyllä käyttäjätestauksen jälkeen sekä videokuvaamalla käyttäjätestejä. Kysely mittasi koettua käytettävyyttä, videotallenteet analysoitiin poikkeamien, eli virheiden, testien oikeista suoritustekniikoista varalta. Tutkimuksen päälöydökset osoittavat, että käytetyllä mobiililaitteella ei todettu olevan vaikutusta koettuun käytettävyyteen, mutta se vaikutti tehtyjen virheiden lukumäärään. Lisäksi todettiin, että ääni- ja tekstiohjeistuksen koetussa käytettävyydessä ei ollut eroa. Visuaalisella apukeinolla oli tilastollisesti merkittävä vaikutus koetun käytettävyyden tulokseen; video ja kuvasarja arvioitiin animaatiota paremmiksi. Vähimpien virheiden ja käytettävyyden paras yhdistelmä havaittiin, kun video tai kuvasarja yhdistettiin tekstiohjeistukseen. Tutkimuksen tulosten perusteella pääteltiin, että standardoituja kuntotestejä on mahdollista suorittaa riittävällä moitteettomuudella ilman ammattilaisohjaajaa
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Kim, Andrew Y. "A Comparative Study of Feature Detection Methods for AUV Localization." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1852.
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Underwater localization is a difficult task when it comes to making the system autonomous due to the unpredictable environment. The fact that radio signals such as GPS cannot be transmitted through water makes autonomous movement and localization underwater even more challenging. One specific method that is widely used for autonomous underwater navigation applications is Simultaneous Localization and Mapping (SLAM), a technique in which a map is created and updated while localizing the vehicle within the map. In SLAM, feature detection is used in landmark extraction and data association by examining each pixel and differentiating landmarks pixels from those of the background. Previous research on the performance of different feature detection methods have been done in environments such as cisterns and caverns where the effects of the ocean are reduced. Our objective, however, is to achieves robust localization in the open ocean environment of the Cal Poly pier. This thesis performs a comparative study between different feature detection methods including Scale Invariant Feature Transform (SIFT), Speeded-Up Robust Features (SURF), and Oriented FAST and Rotated BRIEF (ORB) on different sensors. We evaluate the feature detection and matching performance of these algorithms in a simulated open-ocean environment.
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Visa, Sofia. "Comparative Study of Methods for Linguistic Modeling of Numerical Data." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1043254774.
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Ma, Jiachen. "Comparative Study of Structural Optimization Methods for Automotive Hood Frames." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu159353142765874.
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Brock, Chad Daniel. "Comparative phylogenetic approaches to macroevolution methods, models, and marine fishes /." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/c_brock_041509.pdf.
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Kwag, Jae-Hwan. "A comparative study of LP methods in MR spectral analysis /." free to MU campus, to others for purchase, 1999. http://wwwlib.umi.com/cr/mo/fullcit?p9962536.
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Stoker, Emily B. "Comparative Studies on Scale-Up Methods of Single-Use Bioreactors." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/889.
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This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant kLa was achieved during scale-up from 50 to 2000 L. Using the scale-up constant Pg/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern was recognized in the mixing time data over an increase in volume.
Commonly used methods for predicting kLa upon scale-up were compared to experimental data. New coefficients were determined to fit the historic models to the parameters of this study, namely the unique geometry and low agitation and aeration rates used in the single-use systems. Each of the resulting four models was found to have average error rates from 16-23%. Although the error rates are not statistically different, the Moresi and Patete model was determined to be most conceptually accurate. The Moresi and Patete model found kLa to be more dependent on aeration than on the power input. This finding was consistent with the results of the experimental studies.
The results of this study were for aeration rates (0.02-0.04 vvm) and agitation rates (Pg/V range of 2-20 W/m3) that are commonly used in single-use bioreactor systems.
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Cobb, Matthew. "Recoverable resources calculation using non-linear methods: a comparative study." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2016. https://ro.ecu.edu.au/theses/1809.
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The prediction of recoverable resources at an operating manganese mine is currently undertaken using univariate ordinary kriging of the target variable manganese, and 5 deleterious variables. Input data densities at the time of this calculation are considerably lower than at the time of final selection (grade control), and the potential for unnacceptable conditional bias to be introduced through the use of linear geostatistical methods when determining grade estimates over a small support has led to assessment of the potential benefit of employing the local change of support methods Localised Uniform Conditioning (LUC) and Conditional Simulation (CS). Allowances for the operating conditions, including time frames for estimation / simulation, and likely software limitations are accounted for by also requiring decorrelation to be used in instances where the data are considered in a multivariate sense. A novel method for decorrelation of geostatistical datasets, Independent Components Analysis (ICA), is compared against the more common method of Minimum-Maximum Autocorrelation Factorisation (MAF). ICA performs comparably against MAF in terms of its ability to diagonalise the variance-covariance matrix of the test dataset over multiple lags, for a variety of input data densities and treatments (log-ratio transformed and raw oxide data).
Based on these results, ICA decorrelated data were incorporated into a comparative study of LUC and CS against block ordinary kriging (BOK), using an input dataset of reduced density, treated variously as raw univariate oxide data, decorrelated oxide data, and log-ratio transformed decorrelated data. The use of the log-ratio transform, designed to account for the 100% sum constraint inherent to the input data, proved impractical for LUC due to difficulties associated with the discrete Gaussian model change of support method employed by this technique. Log-ratio data transformation was restricted to use with CS where back transformation to raw oxide space could take place on a pseudo-equivalent support to the input data, prior to change of support. While use of the log-ratio transformation for CS guaranteed adherence to the sum constraint for results (the only method to do so) it resulted in distortion to both the spatial and grade distribution of results.
Decorrelation by ICA also posed difficulties, with biases introduced to final back transformed results as a result of the decorrelation algorithm in both log-ratio transformed and oxide data, which in some instances caused impossible negative values to be returned for some variables in the final results. In a comparison of net profit calculations for each method, the distortions introduced from both log-ratio transformation, and decorrelation become evident in either overly optimistic or conservative profit distributions for methods in which they were used. Of the results presented, only BOK, CS and LUC of non-decorrelated oxide data appear to show results similar to those which would be used at the operation during final selection (based on ordinary kriging of a complete dataset). Based on the comparison of spatial grade distributions and both net profit spatial distribution and summary, the decision to employ a non-linear method of recoverable resource calculation at the operation under question would be questionable in terms of its reward for effort, given that the current method of BOK appears to produce equivalent results.
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Snowden, Kelly E. "Teacher Perceptions of the Flipped Classroom: Using Video Lectures Online to Replace Traditional In-class Lectures." Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc149663/.
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Advancements in media technologies have resulted in increased student usage causing teachers to struggle to be able to engage and hold student’s interest in a typical classroom. As students’ needs change, the field of education changes. One strategy that is gaining in popularity among teachers is the implementation of the “flipped classroom” also known as the “inverted classroom” or “reverse instruction” - a method incorporates technology to “flip” or “reverse” what is typically done in class with what is typically done as homework. Through teacher interviews of eight core teachers, this study attempts to discover teacher perceptions of the use of this method. Results of the study reveal that perceptions of the method are more positive among teachers who typically use lecture as a primary mode of information dissemination.
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Neequaye, Beryl Koteikor. "Reviewing the Quality of Mixed Methods Research Reporting in Comparative and International Education: A Mixed Methods Research Synthesis." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1565886346044592.
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Rattfält, Linda. "A comparative study of two structural methods for fault isolation analysis." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2222.
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Technical systems of today are often complex and integrated. If a fault occurs, the consequences can be disastrous both for the system itself and its surroundings. To maintain the operation and the security it is necessary to have a surveillance system which can detect a fault in an early stage.
In this thesis two structural methods for fault isolation analysis are discussed. The result from the studied algorithms shows what fault isolation properties a diagnostic model is expected to have. If the isolability is not good enough, it also gives information on where further modelling needs to be done.
To base a comparison of the two structural analysis algorithms on, four criteria are defined concerning for example realizability of residuals and time complexity. One interesting part of the methods is how dynamic models are handled. It is shown how differential constraints can end up in differential cycles which implies calculatory problems and what effects structural differentiation has on a system.
The algorithms have been tested on an application from the research training network DAMADICS. The result shows how different types of input models in this case give the same result.
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Villacampa, Osiris. "Feature Selection and Classification Methods for Decision Making: A Comparative Analysis." NSUWorks, 2015. http://nsuworks.nova.edu/gscis_etd/63.
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The use of data mining methods in corporate decision making has been increasing in the past decades. Its popularity can be attributed to better utilizing data mining algorithms, increased performance in computers, and results which can be measured and applied for decision making. The effective use of data mining methods to analyze various types of data has shown great advantages in various application domains. While some data sets need little preparation to be mined, whereas others, in particular high-dimensional data sets, need to be preprocessed in order to be mined due to the complexity and inefficiency in mining high dimensional data processing. Feature selection or attribute selection is one of the techniques used for dimensionality reduction. Previous research has shown that data mining results can be improved in terms of accuracy and efficacy by selecting the attributes with most significance. This study analyzes vehicle service and sales data from multiple car dealerships. The purpose of this study is to find a model that better classifies existing customers as new car buyers based on their vehicle service histories. Six different feature selection methods such as; Information Gain, Correlation Based Feature Selection, Relief-F, Wrapper, and Hybrid methods, were used to reduce the number of attributes in the data sets are compared. The data sets with the attributes selected were run through three popular classification algorithms, Decision Trees, k-Nearest Neighbor, and Support Vector Machines, and the results compared and analyzed. This study concludes with a comparative analysis of feature selection methods and their effects on different classification algorithms within the domain. As a base of comparison, the same procedures were run on a standard data set from the financial institution domain.
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Bird, Annette Elizabeth. "Thermal methods and comparative seed longevity in the genus Ranunculus L." Thesis, Birkbeck (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428766.
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Štúriková, Elena. "Correlation based methods for ultrasound blood velocity estimation a comparative study /." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 1997. http://arno.unimaas.nl/show.cgi?fid=6817.
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Liang, Xiaodong, and 梁？東. "A comparative study of Galerkin mesh-free and finite element methods." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30147694.
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Ntie, Stephan. "Comparative Phylogeography of Central African Duikers Using Non-invasive Sampling Methods." ScholarWorks@UNO, 2012. http://scholarworks.uno.edu/td/1538.
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The present study sets out to assess patterns of evolutionary diversification in central African duikers (subfamily Cephalophinae). The sampling strategy consisted of collecting geo-referenced duiker feces across 43 sites and seven countries. However, several challenges related to the use of non-invasive samples needed to be addressed prior to large scale DNA amplification. First, the best storage method for obtaining DNA from fecal samples needed to be established. Our study revealed that while silica is best for nuclear microsatellite analyses, RNAlater is the best storage medium for maximal mitochondrial amplification. Moreover, extracting DNA as early as possible always provided the best results. Second, since it is impossible to determine the species identity of duiker feces solely based on their morphology, a simple and reliable molecular method was needed. A tree-based approach based on ~650 base pairs of the control region amplified from reference samples was found to be the most reliable method to recover the identity of unknown samples. Third, for fine scale analyses of population genetic structure, a set of twelve nuclear microsatellites were assembled from existing bovid data. These microsatellites markers were chosen because they are very polymorphic, cross amplify among targeted taxa, co-amplify with combined markers of the same multiplex, and are powerful enough for individual identification. Patterns of mitochondrial and nuclear microsatellite variation were used to test two important hypotheses of diversification in the tropics: the Pleistocene refugia and the riverine barrier hypotheses. Analyses of historical and contemporary population genetic structure were carried out on the three most abundant species in our sampling area: the bay duiker (C. dorsalis), the Peter’s duiker (C. callipygus), and the blue duiker (P. monticola) using mitochondrial and nuclear markers described above. These data show that (1) southwest Nigeria and southwest Cameroon comprise genetically distinct populations in C. callipygus and P. monticola species, (2) signatures of demographic expansion for all three taxa are broadly coincident with the location of hypothesized upland refugia in Gabon and Equatorial Guinea and (3) the Sanaga, Ogooué, and Sangha rivers may constitute a partial riverine barrier and/or act as fluvial refugia for duikers.
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Mackay, Katherine. "A comparative study of analysis methods in quantitative label free proteomics." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2050359/.
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The large amounts of data generated by modern proteomics experiments necessitates the use of software pipelines to conduct the bulk of the post-processing. While many software packages (both commercial and open-source) are available to perform some or all of the necessary post-processing steps, it is usual for each research group to use only the instrumentation and software packages with which they are most familiar and/or which are available to analyse their unknown data. The intention of the studies presented within this thesis was to assess the correlation between the experimental results obtained when; - a single result dataset is obtained and post-processed in parallel using four separate software pipelines - a single sample is analysed on two different mass spectrometers and post-processed in parallel and; - when different identification thresholds are applied to a dataset prior to parallel quantitation of the resultant data sets Correlation between different mass spectrometry instruments was assessed and found to yield high r values, especially at the protein level, and was also found to improve following the application of abundance thresholds, however the result of applying score thresholds was unpredictable. The use of manual FDR thresholds prior to importing data into Progenesis LC-MS yielded interesting results, which suggest that a threshold of 1% peptide FDR and 1 or 2% protein FDR is most effective in terms of yielding accurate ratios while maintaining acceptable sensitivity. In addition, a consensus method is suggested to utilise the results from multiple software pipelines in order to increase sensitivity and reduce the FDR, through the use of the QPROT tool and manual post-processing.