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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

A Multi-Factor Model and Enhanced Index Fund- with Application in Singapore Market

Tsai, Yan-Gen 05 July 2011 (has links)
Quantitative analysis is one branch of portfolio management. The advantages of quantitative analysis are fast and objective. It has developed significantly in recent years because of the improvements in computer technology. This thesis applies the structure of a multi-factor model (MFM) to undertake quantitative analysis. Singapore has one of the most prosperous financial markets in Southeast Asia. The Singapore Stock Exchange (SGX) and Financial Times and the London Stock Exchange (FTSE) are now in cooperation, which has added vitality to this market. It has great influence in global financial markets, and this is why we select its security market to be our target in MFM. The model refers the multi-factor processes of Jeng and Tsai (2011) . For backtesting, we adopt an enhanced strategy as testimony. We transmit information from the MFM to the enhanced strategy. Then we create the stock weightings to constitute the enhanced portfolio. This model includes 68 significant descriptors, 14 composite factors and 7 industry factors. The Singapore MFM shows 43% adjusted R-Square in the sample period. The enhanced portfolio we suggested has an information ratio of 76.80% with a tracking error of 4.02% and 1.53% for monthly turnover rate.
62

Studying the Risk Management Model of Petrochemical Enterprises by Risk Base Inspection System

Chen, Kuo-Liang 24 August 2011 (has links)
ABSTRACT Redirecting the inspection plan to place emphasis on high risk equipment items is not the only objective when implementing Risk Base Inspection (RBI). Rather it would be much more fruitful if company staff were educated to be equipped with the capability of identifying potential risks and were willing to actually put into real practice in eliminating all these potential threats to an enterprise. Since its release, the API-580 technology has seen growing acceptance and becomes a popular methodology in maintaining the mechanical integrity of pressure equipment and piping. In addition to U.S.A, many other country including European nations and Japan have also assimilated the same risk concepts into regulations that require plant operators to aim for practical performance of equipment management, not at the extent of obligations required by the government. Such a risk-based concept is not just incorporated in regulations, when utilized in close conjunction with plant maintenance and inspection, becomes a powerful tool in helping determine optimal inspection intervals of pressure equipment. In order for the equipment management system to perform effectively, fundamental tasks such as failure mechanisms identification and effectiveness of inspection methods are keys to a successful RBI program. Some might question Risk Base Inspection (RBI) to be a conservative, less aggressive approach that rather than opting for more aggressive managerial methods, it recommends to focus on the whole life cycle of plant equipment. Keywords: API-581¡BRBI¡Bbusiness risk¡Bbusiness administration¡Bquantitative analysis¡Bconsequence analysis¡Brisk base inspection
63

An Assessment of International Regulations for the Prevention of Air Pollution from Ships

Kuo, Wen-Tzu 18 July 2012 (has links)
The International Maritime Organization(IMO) has adopted a draft of the International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto and by the Protocol of 1997(termed as MARPOL 73/78/97)since September 1997, amended the Convention and added a new Annex VI which regulates gas pollution emitted from ships, the latest Annex came into effect after the MARPOL convention. This study aims to discuss the effect of the Annex VI Prevention of Air Pollution from Ships after it was implemented on 19 May 2005 and the growth and decline status of pollution by document analysis and quantitative analysis methods. This study find that there were different concern positions from each PSC region, the enforcement state of Europe, Asia-Pacific and Indian Ocean regions were better than Black Sea, west and central Africa, Latin America and Caribbean regions. The statistical show that sulfur oxides decreased notably, nitrogen oxides and carbon dioxides decreased slowly by UNFCCC web; in addition, some countries did not submit their gas inventory, including developed countries: Canada, United States of America, Japan, Luxembourg and Netherlands et al. The quantitative analyses show that some countries has decreased or slow down the ship-source gas pollution with countries¡¦ economy developed, including Denmark, Ireland, Norway, Germany, Belgium, Luxembourg, Japan, Australia and United States of America et al.
64

Meta-regression Analysis of Purchasing Power Parity Puzzles

Tseng, Po-Hsin 18 January 2008 (has links)
Purchasing Power Party (PPP) has long been intensively studied in empirical researches. However, a unanimous conclusion has not been reached. As an alternative to a narrative literature review, this paper conducts a meta-regression analysis of a collection of thirty-three studies, in order to uncover the sources of variation in the empirical findings relating to PPP. We also test the validities of suggestions made by the narrative literature reviewers that the use of more years of data, more countries, more powerful tests, more general model specifications, and an allowance for non-linearity might mitigate the issue of PPP puzzle. We find that the proposition is true and that whether PPP holds in the long run mainly depends on the methodology employed, the regimes the data are sampled from, and the length of the sample of data that is used. When addressing the persistence of the deviations from PPP, it mostly depends on the methodologies adopted.
65

”What’s the difference between men and women?” : En studie av genusporträttering i TV-serien The Walking Dead

Hasani, Amila, Marinoni, Sandra January 2015 (has links)
This study aims to find out how gender roles are portrayed in the series The Walking Dead. Using a quantitative content analysis where every episode of The Walking Dead was analyzed the study shows gender role portrayal in the everyday activities done by the characters. A qualitative study based on a semiotic analysis was also executed where focus lies on analyzing the characters attributes and their trait of character. The result shows that the series maintains a stereotypical representation of men and women. The men take on the typical “manly” work and the women do the majority of the domestic work. The killing of zombier and humans are mostly done by the men in the series. Their trait of character also shows a stereotypical gender role representation where the men are portrayed as tough, fighters, protectors and providers. The women on the other hand are more weak, sensitive and dependent.
66

MODELING AND QUANTITATIVE ANALYSIS OF WHITE MATTER FIBER TRACTS IN DIFFUSION TENSOR IMAGING

Liang, Xuwei 01 January 2011 (has links)
Diffusion tensor imaging (DTI) is a structural magnetic resonance imaging (MRI) technique to record incoherent motion of water molecules and has been used to detect micro structural white matter alterations in clinical studies to explore certain brain disorders. A variety of DTI based techniques for detecting brain disorders and facilitating clinical group analysis have been developed in the past few years. However, there are two crucial issues that have great impacts on the performance of those algorithms. One is that brain neural pathways appear in complicated 3D structures which are inappropriate and inaccurate to be approximated by simple 2D structures, while the other involves the computational efficiency in classifying white matter tracts. The first key area that this dissertation focuses on is to implement a novel computing scheme for estimating regional white matter alterations along neural pathways in 3D space. The mechanism of the proposed method relies on white matter tractography and geodesic distance mapping. We propose a mask scheme to overcome the difficulty to reconstruct thin tract bundles. Real DTI data are employed to demonstrate the performance of the pro- posed technique. Experimental results show that the proposed method bears great potential to provide a sensitive approach for determining the white matter integrity in human brain. Another core objective of this work is to develop a class of new modeling and clustering techniques with improved performance and noise resistance for separating reconstructed white matter tracts to facilitate clinical group analysis. Different strategies are presented to handle different scenarios. For whole brain tractography reconstructed white matter tracts, a Fourier descriptor model and a clustering algorithm based on multivariate Gaussian mixture model and expectation maximization are proposed. Outliers are easily handled in this framework. Real DTI data experimental results show that the proposed algorithm is relatively effective and may offer an alternative for existing white matter fiber clustering methods. For a small amount of white matter fibers, a modeling and clustering algorithm with the capability of handling white matter fibers with unequal length and sharing no common starting region is also proposed and evaluated with real DTI data.
67

Microfluidic systems and analytical tools for genetic screening, optogenetics, and neuroimaging of C. elegans

Lee, Hyewon 09 April 2013 (has links)
This thesis seeks to address the critical bottlenecks of current technologies that have slowed the neuroscience research in C. elegans. The objective of this research is to enhance the currently developed systems through the design and construction of simple microdevices and quantitative analytical tools for high-throughput phenotyping C. elegans to investigate functions of nervous systems. First, we developed and used the integrated system combining user-friendly single-layer microfluidics and quantitative analytical tools to study the genetic regulation of target gene expression. We found several putative mutants based on large-scale screens, which would have previously been too labor-intensive to attempt. Second, we developed a simple mathematical model that describes the regulation of a target gene expression. Using the model developed, we simulated phenotypical space of hypothetical mutants to suggest plausible genetic pathways some isolated mutants may affect. Lastly, we developed a high-density multichannel device for rapid trapping, parallel selective stimulating, long-term culturing, and (often repeatedly). We used this integrated system to study the neurodegenerative process based on selective ablation of multiple animals using an optogenetic tool, which would have been taken at least 1 order of magnitude longer. Taken together, we expect that these developments will greatly facilitate a broad range of fundamental, and application studies including aging, neurodegeneration, circuit and behavior.
68

Development of a cheap and rapid method to determine calcium in milk fractions in an industrial environment

Kaur, Daljit January 2007 (has links)
Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.
69

Development of a cheap and rapid method to determine calcium in milk fractions in an industrial environment

Kaur, Daljit January 2007 (has links)
Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.
70

Trade-off in resource allocation between behaviour and production in fowl : phenotypic studies and QTL-analyses in red junglefowl, white leghorn and their F₂-progeny /

Schütz, Karin, January 2002 (has links) (PDF)
Diss. (sammanfattning) Skara : Sveriges lantbruksuniv., 2002. / Härtill 4 uppsatser.

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