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A New Measure For Clustering Model SelectionMcCrosky, Jesse January 2008 (has links)
A new method for determining the number of k-means clusters in a given data set is presented. The algorithm is developed from a theoretical perspective and then its implementation is examined and compared to existing solutions.
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Influence of damping winding, controllersettings and exciter on the damping of rotorangle oscillations in a hydroelectric generator : The testing of a mathematical modellHanning, Jonathan January 2011 (has links)
This thesis has been performed in the university context for Master thesis 30 credits,which is a compulsory exercise in order to gain a degree in electrical engineering. The thesis main objectives were to investigate how the damping and the stiffness of ahydroelectric generator changed depending on different parameter values, and to testa new mathematical model to calculate the damping and stiffness constants Kd and Ks.The work has been performed at the request of VG Power, but has been performedat the division for electricity at Uppsala University. The reason for undertaking thisthesis was to ensure that generators are robust. But also when building future modelsfor generators, to have a system that can be used to compute robustness. During this thesis a power cabinet has also been constructed to be able to test thesimulated model on a real generator. Under the first five weeks a power cabinet wasconstructed in the laboratory at the division for electricity. The tests were thenperformed at a generator with a rated power of 75 kVA.
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Parameterized Code Generation From Template SemanticsProut, Adam January 2006 (has links)
We have developed a tool that can create a Java code generator for a behavioural modelling notation given only a description of the notation's semantics as a set of parameters. This description is based on template semantics, which has previously been used to describe a wide variety of notations. As a result, we have a technique for generating Java code for models written in any notation describable in template semantics. Since template semantics allows for models containing nondeterminism, we introduce mechanisms for eliminating this nondeterminism when generating code. We describe Java implementations of several template-semantics composition operators that have no natural Java representations and give some techniques for optimizing the generated code without sacrificing correctness. The efficiency of our generated code is comparable to that of commercial notation-specific code generators.
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A New Measure For Clustering Model SelectionMcCrosky, Jesse January 2008 (has links)
A new method for determining the number of k-means clusters in a given data set is presented. The algorithm is developed from a theoretical perspective and then its implementation is examined and compared to existing solutions.
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The importance of the F4 receptor in post-weaned pigs In eliciting F4 specific immune responses in the intestineDanabassis, Michael 29 May 2006 (has links)
In this Masters dissertation, various doses of solubulized crude F4 fimbrial protein in conjunction with the adjuvants CpG ODN and porcine â-defensin 1 (pBD-1) were used to enhance the F4-specific intestinal immune response against Enterotoxigenic Escherichia coli (ETEC) F4 in post-weaned pigs. Using the mechanically shearing method we isolated the F4 fimbrial protein of ETEC with a molecular weight of 26 kDa. We verified this using a Western blot probed with a rabbit anti-F4 fimbrial antibody. Binding of the F4 fimbrial protein to the F4 receptor (F4R), present on the brush border of the villi in the small intestine of pigs, was demonstrated using an in vitro villus adhesion assay (IVVA). To demonstrate specificity rabbit polyclonal and mouse monoclonal anti-F4 antibodies, or the F4 protein were used to inhibit the adhesion of ETEC F4ac to F4R positive (F4Rpos) villi. <p>To examine immunogenicity of the 500 micrograms (ìg) of the F4 were administered into surgically created jejunal gut-loops in pigs. Three weeks later Peyers patches (PP) from immunized and control loops as well as gut-wall tissue were analyzed for their F4-specific antibody secreting cells (ASCs) by a modified enzyme linked immunosorbent spot (ELISPOT) assay. The F4-specific immune response in the serum was analyzed by an enzyme linked immunosorbant assay (ELISA). High numbers of F4-specific ASCs were isolated from the loops of pigs that contained high levels of the F4R. Conversely nominal or low numbers of F4-specific ASCs were found in loops of pigs expressing low levels of the F4R or no F4R (F4Rneg). The IVVA was used to categorize the pigs into either F4Rpos or F4Rneg animals. <p>Next three different concentrations of the crude F4 protein 50, 250, and 500 µg in the loops of individual pigs were used to analyze if dose affected the F4-specific immune response. Interestingly dose had no effect on the magnitude of the response. Therefore we hypothesized that the F4-specific immune response in the loops could be enhanced through the use of the adjuvants CpG ODN 2007 and pBD-1. The F4 protein was co-administered with either CpG ODN 2007 or pBD-1 and immune responses were assessed after 3 weeks. However neither CpG ODN 2007 nor PBD-1 at the doses used made an improvement in the immune response. Thus, these results demonstrated that the expression level of the F4R was the most important parameter for eliciting of the local immune response against the F4 protein. Furthermore our studies revealed that both F4Rneg and F4Rpos pigs responded to F4 immunization, however the former respond only nominally to F4-immunization in the loops. Moreover, an inverse relationship existed between the level of the F4-specific IgG in the serum and the F4-specific immune response seen in the loops. Thus our findings have important implications for oral vaccination using fimbrial based antigens (Ags) that utilize a receptor for their immunogenicity. Our results indicate that only animals with high levels of enterocyte F4R will have the ability to elicit high levels of protective F4-specific anti-fimbrial antibodies in their intestine after oral immunization. Therefore unless an effective adjuvant is available, animals with low to moderate levels of the fimbrial receptor in their small intestine will mount only weak immune responses making herd immunity after vaccination currently unattainable.
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Evaluation of commercial air dispersion models for livestock odour dispersion simulationXing, Yanan 02 January 2007 (has links)
The public nuisance and health concerns caused by odours from livestock facilities are among the key issues that affect neighbouring communities and the growth of the livestock industry across Canada. A setback distance is the common regulatory practice to reduce odour impact on the neighbouring areas. The air dispersion modeling method may be a more accurate tool for establishing setback distances since it considers site-specific airborne emissions, such as odour and gases from the animal production site as well as weather conditions and then estimates a concentration of the pollutant (odour, ammonia, etc.). Although various dispersion models have been studied to predict odour concentration from agricultural sources, limited field data exist to evaluate their applicability in agricultural odour dispersion. Thus, the purpose of this project was to evaluate the selected commercial air dispersion models with field plume measurements from swine operations. <p>Firstly, this thesis describes a sensitivity analysis of how the climatic parameters affect model simulations for four selected air dispersion models, ISCST3, AUSPLUME, CALPUFF, and CALPUFF. Under the steady state weather condition, mixing height had no effect on the livestock odour dispersion, while atmospheric stability, wind speed and wind direction had great effect on the livestock odour dispersion. Ambient temperature had a moderate effect compared with other parameters. Under variable weather conditions, the predicted odour concentrations were much lower than the results under steady state weather conditions. <p>A series of comparisons between model predictions of the same four models and field odour measurements were conducted. When using the livestock odour plume measurement data from University of Manitoba, three equations were used to convert the model predicted odour concentration to field measured odour intensity. The equations did not predict odour intensity very well. No model showed obvious better performance than the others. Scaling factors did not improve the results considerably. When using the odour plume measurement data from University of Minnesota, INPUFF2 performed better than CALPUFF. Scaling factors did improve the modeled results. When using the odour plume measurement data from University of Saskatchewan, INPUFF2 also performed better than CALPUFF. Scaling factors were still useful for the results improvements.<p>Finally, because CALPUFF is the US EPA preferred model and predicted the highest values under variable weather conditions in the sensitivity study, we used it to simulate odour plumes on selected three swine sites using hourly weather data from 1993 to 2002 in Yorkton, Saskatchewan. The maximum predicted distance were 2.9 km for 1 OU, which was lower than the recommended maximum setback distance of 3.2 km. <p>It is recommended that the variable weather conditions be used in the setback distance determination. CALPUFF is the preferred model and INPUFF2 is another option for field odour plume simulation, however scaling factors are needed to bring the model predictions close to the field measured results. Because the models evaluated were not developed for odour dispersion simulation, a model that can accurately predict livestock odour dispersion should be developed to take into account of the difference between odour and gas and wind direction shifts within the simulation time interval.
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Juvenile Delinquency in Five High Schools in Shenyang, China: An Empirical Analysis under an Integrated ModelWang, Wei 12 August 2009 (has links)
Youth crime has been increasing rapidly since the Economy Reform and Open-door Policy in 1979 and become a serious social problem in China. Researches on explanations of juvenile delinquency, however, are relatively limited, while a number of scholars in western countries have developed delicate theoretical models to explore this problem. General strain, differential association, and social bond theory are employed in the current study to test if western theories can be applied to a different social context and to empirically explain the causes of youth crime in China. An integrated model is addressed through a self-reported survey with 385 respondents. The respondents are high school students in the city of Shenyang, aged from 16 to 18. Data from the questionnaire survey suggests that these three theories could explain Chinese youth crime. Two separate Ordinary Least Squares (OLS) models are built for analyzing delinquency of males and females. Predictors related to strain and differential association theory are directly associated with youth crime, while weak social bonds have indirect impacts on juvenile delinquency. Males and females are influenced by different factors when they are involved in delinquency. The thesis concludes with a discussion of establishing a theoretical integrated model for Chinese adolescence and provides policy implications for protection programs.
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Using data mining to dynamically build up just in time learner modelsLiu, Wengang 09 February 2010 (has links)
Using rich data collected from e-learning systems, it may be possible to build up just in time dynamic learner models to analyze learners' behaviours and to evaluate learners' performance in online education systems. The goal is to create metrics to measure learners' characteristics from usage data. To achieve this goal we need to use data mining methods, especially clustering algorithms, to find patterns from which metrics can be derived from usage data. In this thesis, we propose a six layer model (raw data layer, fact data layer, data mining layer, measurement layer, metric layer and pedagogical application layer) to create a just in time learner model which draws inferences from usage data. In this approach, we collect raw data from online systems, filter fact data from raw data, and then use clustering mining methods to create measurements and metrics.<p>
In a pilot study, we used usage data collected from the iHelp system to create measurements and metrics to observe learners' behaviours in a real online system. The measurements and metrics relate to a learner's sociability, activity levels, learning styles, and knowledge levels. To validate the approach we designed two experiments to compare the metrics and measurements extracted from the iHelp system: expert evaluations and learner self evaluations. Even though the experiments did not produce statistically significant results, this approach shows promise to describe learners' behaviours through dynamically generated measurements and metric. Continued research on these kinds of methodologies is promising.
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The Business Model of Chinese Manufacturing Born Global CompaniesHuang, Hanjun, Shen, Ran January 2012 (has links)
Regarding that the business model is widely used in e-business, we consider that every business should have its own business model which helps a company to evaluate the business and also create a dynamic business. In addition, the emphasis of this research is combined with another element – Born Global, which caters the globalization trend in recent decades. In fact, there are more and more Born Globals setting up in emerging market countries such as China, especially most of them are involved in manufacturing industry. In this case, the focus of this research is on the business model of Chinese manufacturing Born Globals. We investigate deeply through the interaction of each component of the business model to see how Chinese manufacturing Born Globals design and manage their business to achieve successful internationalization within China’s particular political and social background. After reviewing abundant literatures about business model components, we conclude them into 11 components categories. Furthermore, we combine the critical success factors of Chinese Born Globals with the business model components we summarized together to find what elements may more important to Chinese Born Globals’ internationalization. Based on these, we build a new framework which includes all the 11 elements, 3 interfaces, 2 frames and 1 external environment factor to investigate how these elements interact with each, what is the logic behind the business model generally and how the external environment influence the business model. At the end, we give out a probable evaluation method for the business model. Qualitative case study is adopted in this paper. We choose a Chinese manufacturing Born Global as case company. Both secondary and primary data are used in this research. We gather primary data through questionnaire survey and 4 times interviews. Due to the wide range of our topic and large size of our case company, we use a lot secondary data to get more comprehensive understandings of the case company. Through the analysis of case company, we get the main picture of how Chinese manufacturing Born Glonals’ business model look like. In the conclusion, firstly we give out a brief description of what is Chinese manufacturing Born Globals’ business model. Moreover, we find the human resources within the business model cause Chinese Born Globals’ production ability, innovation ability and finally contribute to its important OEM production. As a result, we actually use the Chinese manufacturing Born Globals’ business model to explain their rapid international success. Besides that, we also get some new findings of Chinese manufacturing Born Globals from the aspects of internationalization motivation, process and success factors. According to the evaluation of Chinese manufacturing Born Globals’ business model, we find some crucial problems for example the lost brand value, the low profit and poor sustainability. These conclusions actually provide some managerial suggestions for Chinese manufacturing companies who aim to go abroad or reform their business models. / no
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A study of the reaction products of lignin model compounds and sodium hydrosulfide.Zentner, Thomas G. (Thomas Glenn) 01 January 1952 (has links)
No description available.
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