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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.
171

生產線外品質工程在食品製造業應用之研究 / Application of Off-line Quality Engineering in Food manufactoring

許禎娟, Hsu,Chen Chuan Unknown Date (has links)
近年來,隨著消費意識的提升,食品業者正面臨最嚴格的考驗,品質 產 生變異,將會反應在銷售量上,嚴重影響企業的經營。而目前台灣食品 造業者,有許多廠家仍停留在經驗掛帥、老式的檢驗品質階段,對於源流 瑊z的觀念仍不甚了解,致使品質提昇的效率不盡理想。有鑑於此,本研 究B用田口玄一博士生產線外品質工程理念架構,靈活搭配各種工具(如 系統洈k、直交表),以使田口方法更臻完善。同時利用S/N比(signal- to-Noes Ratio)變異數分析兩種方法進行資料解析,提供食品製造業者 最佳生ㄡ捰X。最後,乃以本人所親自參與之食品製造業品質改善研究實 驗為例,憭什ㄟ筆嗾膋熊痕G報告外,另詳述記載寶貴的實驗經歷,可進 一步提供相鶻t商作為改善品質的借鏡。
172

Empirical Bayes Methods for DNA Microarray Data

Lönnstedt, Ingrid January 2005 (has links)
<p>cDNA microarrays is one of the first high-throughput gene expression technologies that has emerged within molecular biology for the purpose of functional genomics. cDNA microarrays compare the gene expression levels between cell samples, for thousands of genes simultaneously. </p><p>The microarray technology offers new challenges when it comes to data analysis, since the thousands of genes are examined in parallel, but with very few replicates, yielding noisy estimation of gene effects and variances. Although careful image analyses and normalisation of the data is applied, traditional methods for inference like the Student <i>t</i> or Fisher’s <i>F</i>-statistic fail to work.</p><p>In this thesis, four papers on the topics of empirical Bayes and full Bayesian methods for two-channel microarray data (as e.g. cDNA) are presented. These contribute to proving that empirical Bayes methods are useful to overcome the specific data problems. The sample distributions of all the genes involved in a microarray experiment are summarized into prior distributions and improves the inference of each single gene.</p><p>The first part of the thesis includes biological and statistical background of cDNA microarrays, with an overview of the different steps of two-channel microarray analysis, including experimental design, image analysis, normalisation, cluster analysis, discrimination and hypothesis testing. The second part of the thesis consists of the four papers. Paper I presents the empirical Bayes statistic <i>B</i>, which corresponds to a <i>t</i>-statistic. Paper II is based on a version of <i>B</i> that is extended for linear model effects. Paper III assesses the performance of empirical Bayes models by comparisons with full Bayes methods. Paper IV provides extensions of <i>B</i> to what corresponds to <i>F</i>-statistics.</p>
173

Empirical Bayes Methods for DNA Microarray Data

Lönnstedt, Ingrid January 2005 (has links)
cDNA microarrays is one of the first high-throughput gene expression technologies that has emerged within molecular biology for the purpose of functional genomics. cDNA microarrays compare the gene expression levels between cell samples, for thousands of genes simultaneously. The microarray technology offers new challenges when it comes to data analysis, since the thousands of genes are examined in parallel, but with very few replicates, yielding noisy estimation of gene effects and variances. Although careful image analyses and normalisation of the data is applied, traditional methods for inference like the Student t or Fisher’s F-statistic fail to work. In this thesis, four papers on the topics of empirical Bayes and full Bayesian methods for two-channel microarray data (as e.g. cDNA) are presented. These contribute to proving that empirical Bayes methods are useful to overcome the specific data problems. The sample distributions of all the genes involved in a microarray experiment are summarized into prior distributions and improves the inference of each single gene. The first part of the thesis includes biological and statistical background of cDNA microarrays, with an overview of the different steps of two-channel microarray analysis, including experimental design, image analysis, normalisation, cluster analysis, discrimination and hypothesis testing. The second part of the thesis consists of the four papers. Paper I presents the empirical Bayes statistic B, which corresponds to a t-statistic. Paper II is based on a version of B that is extended for linear model effects. Paper III assesses the performance of empirical Bayes models by comparisons with full Bayes methods. Paper IV provides extensions of B to what corresponds to F-statistics.
174

Alignment and Variable Selection Tools for Gas Chromatography – Mass Spectrometry Data

Sinkov, Nikolai Unknown Date
No description available.
175

Rational Supply Planning In Resource Constrained Electricity Systems

Balachandra, P 12 1900 (has links)
Electricity is the most preferred source of energy, because of its quality and convenience of usage. It is probably one of the most vital infrastructural inputs for economic development of a country. Indeed it is the fulcrum which can leverage the future pace of growth and development. These reasons have made the electric power industry one of the fastest growing sectors in most developing countries and particularly in India. Therefore it is not surprising to observe the economic growth of a country being related to the increase in electricity consumption. In India, the growth rate of demand for power is generally higher than that of Gross Domestic Product (GDP). However, to achieve this kind of growth in electricity supply, the capital investments required are very huge. Even though the electricity sector generally gels a major share in the budgetary allocations in India, this is inadequate to add the required quantum of new generation capacity to keep pace with the increase in demand for electricity. Additional constraints like capital scarcity in the public sector, lack of enthusiasm among the private and foreign investors, and strong opposition from the environmentalists have further contributed to this slow pace of new generating capacity addition. This has resulted in severely constrained systems in India. The main focus of the present research work is on the development of an integrated approach for electricity planning using a mathematical modeling framework in (he context of resource constrained systems. There are very few attempts in the literature to integrate short, medium and long term issues in electricity planning. This is understandable from the point of view of unconstrained electricity systems where this type of integration is unnecessary since such systems have a luxury of surplus capacity to meet the current demand and capacity additions are required only for meeting predicted future increase in demand. However, in the case of constrained electricity systems, which are characterized by shortages, this kind of integration is very essential. These systems have to manage with inadequate capacity in the present, plan capacity additions to bridge the existing gap and to meet future increase in demand, and always explore the possibility of adding capacity with short gestation period. The integrated approach is expected to achieve effective supply-demand matching on a continuous basis encompassing both the short term and long term horizons. To achieve this, we have considered three alternatives- existing supply, new supply and non-supply (rationing) of electricity. The electricity system of the state of Karnataka, which is severely constrained by both limited capital and energy resources, has been selected for this purpose. As a first step, the supply and demand situation has been studied in the context of resource constraints. In terms of supply, both existing and future additions are studied in detail with respect to the potential created, generation types, import potential, technical constraints, energy and power shortages, planned and proposed capacity additions by both public and private sectors, etc. The demand patterns have been studied by introducing a new concept of "Representative Load Curves (RLCs)". These RLCs are used to model the temporal and structural variations in demand for electricity. Also, appropriate non-supply options (rationing measures) for effective management of shortages are identified. Incorporating this information, an integrated mathematical model, which is expected to generate a target plan for a detailed generation scheduling exercises and a requirement plan for a regular generation expansion planning, has been developed. The other important alternative "Demand-Side-Management (DSM)", which could be considered as an effective option to achieve efficient supply-demand matching has not been included in the present research work. The major reason for not including the DSM alternatives is due to the difficulty in integrating these in the modelling approach adopted here. In the present approach we have used typical daily load curves (RLCs) to represent the demand for electricity. These are aggregate load curves and do not contain any sector-wise or end-use-wisc details. On the other hand, DSM alternatives are end-use focused. To incorporate DSM alternatives, we should have information on end-usc-wisc power demand (kW or MW), savings potential, time-of-use, etc. For this purpose it may be required to have end-use-wisc daily load curves. This information is not available and a separate detailed survey may be required to generate these load curves. This, we felt, is out of the scope of this present research work and a separate study may be required to do this. Therefore, we restricted our focus to supply planning alone. A detailed literature review is conducted to understand different types of modeling approaches to electricity planning. For the present study, however, the review of literature has been restricted to the methods of generation expansion planning and scheduling. In doing so, we attempted to bring out the differences in various approaches in terms of solution methods adopted, alternatives included and modifications suggested. Also, we briefly reviewed the literature on models for power and energy rationing, because management of shortages is an important aspect of the present study. Subsequently, a separate section is devoted to present an overview of the non-supply of electricity and its economic impacts on the consumers. We found that the low reliability of the electrical system is an indicator of the existence of severe shortages of power and energy, which cause non-supply of electricity to the consumers. The overview also presented a discussion on reasons for non-supply of electricity, and the types of non-supply options the utilities adopt to over come these shortages. We also attempted to explain what we mean by non-supply of electricity, what are its cost implications, and the methods available in the literature to estimate these costs. The first objective of the research pertains to the development of a new approach to model the varying demand for electricity. Using the concept of Representative Load Curves (RLCs) we model the hourly demand for a period of four years, 1993-94, 1994-95, 1995-96 and 1996-97, to understand the demand patterns of both unconstrained and constrained years. Multiple discriminant analysis has been used to cluster the 365 load curves into nine RLCs for each of the four years. The results show that these RLCs adequately model the variations in demand and bring out the distinctions in the demand patterns existed during the unconstrained and constrained years. The demand analysis using RLCs helped to study the differences in demand patterns with and without constraints, impacts of constraints on preferred pattern of electricity consumption, success of non-supply options in both reducing the demand levels and greatly disturbing the electricity usage patterns. Multifactor ANOVA analyses are performed to quantify the statistical significance of the ability of the logically obtained factors in explaining the overall variations in demand. The results of the ANOVA analysis clearly showed that the considered factors accounted for maximum variations in demand at very high significance levels. It also brought out the significant influence of rationing measures in explaining the variations in demand during the constrained years. Concerning the second objective, we explained in detail, the development of an integrated mixed integer-programming model, which we felt is appropriate for planning in the case of resource constrained electricity systems. Two types of integrations are attempted (i) existing supply, non-supply and new supply options for dynamically matching supply and demand, (ii) operational and strategic planning in terms of providing target plans for the former and requirement plans for the latter. Broadly, the approach addresses the effective management of existing capacity, optimal rationing plan to effectively manage shortages and rationally decide on the new capacity additions both to bridge the existing gap between supply and demand, and to meet the future increases in demand. There is also an attempt to arrive at an optimal mix of public and private capacity additions for a given situation. Finally, it has been attempted to verify the possibility of integration of captive generation capacity with the grid. Further, we discussed in detail about the data required for the model implementation. The model is validated through the development of a number of scenarios for the state of Karnataka. The base case scenario analyses are carried out for both the unconstrained and constrained years to compare the optimal allocations with actual allocations that were observed, and to find out how sensitive are the results for any change in the values of various parameters. For the constrained years, a few more scenarios are used to compare the optimal practice of managing shortages with to what has been actually followed by the utility. The optimal allocations of the predicted demand to various existing supply and non-supply options clearly showed that the actual practice, reflected by the actual RLCs, are highly ad hoc and sub-optimal. The unit cost comparisons among different scenarios show that the least cost choice of options by the utility does not necessarily lead to good choices from the consumers’ perspective. Further, a number of future scenarios are developed to verify the ability of the model to achieve the overall objective of supply-demand matching both in the short and long term. For this purpose both the short horizon annual scenarios (1997-98 to 2000-01) and long horizon terminal year scenarios (2005-06 and 2010-11) are developed assuming capacity additions from only public sector. Overall, the results indicated that with marginal contributions from non-supply options and if the public sector generates enough resources to add the required capacity, optimal matching of supply and demand could be achieved. The scenario analyses also showed that it is more economical to have some level of planned rationing compared to having a more reliable system. The quantum of new capacity additions required and the level of investments associated with it clearly indicated the urgent need of private sector participation in capacity additions. Finally, we made an attempt to verify the applicability of the integrated model to analyse the implications of private sector participation in capacity additions. First, a number of scenarios are developed to study the optimal allocations of predicted hourly demand to private capacity under different situations. Secondly, the impacts of privatisation on the public utility and consumers are analysed. Both short term and long term scenarios are developed for this purpose. The results showed the advantage of marginal non-supply of electricity both in terms of achieving overall effective supply-demand matching and economic benefits that could be generated through cost savings. The results also showed the negative impacts of high guarantees offered to the private sector in terms of the opportunity costs of reduced utilization of both the existing and new public capacity. The estimates of unit cost of supply and effective cost of supply facilitated the relative comparison among various scenarios as well as finding out the merits and demerits of guarantees to private sector and non-supply of electricity. The unit cost estimates are also found to be useful in studying the relative increase in electricity prices for consumers on account of privatization, guarantees and reliable supply of electricity. Using the results of scenario analyses, likely generation expansion plans till the year 2010-11 are generated. The analyses have been useful in providing insights into fixing the availability and plant load factors for the private sector capacity. Based on the analysis, the recommended range for plant utilization factor is 72.88 - 80.57%. The estimated generation losses and the associated economic impacts of backing down of existing and new public capacity on account of guarantees offered to private sector are found to be significantly high. The analyses also showed that the backing down might take place mainly during nights and low demand periods of monsoon and winter seasons. Other impacts of privatization that studied are in terms of increased number of alternatives for the utility to buy electricity for distribution and the associated increase in its cost of purchase. Regarding the consumers, the major impact could be in terms of significant increase in expected tariffs. The major contributions of this thesis are summarized as follows: i. An integrated approach to electricity planning that is reported here, is unique in the sense that it considers options available under various alternatives, namely, existing supply, non-supply and new supply. This approach is most suited for severely constrained systems having to manage with both energy and capital resource shortages. ii. The integration of operational and strategic planning with coherent target plans for the former and requirement plans for the latter bridges the prevailing gap in electricity planning approaches. iii. The concept of Representative Load Curves (RLCs), which is introduced here, captures the hourly, daily and seasonal variations in demand. Together, all the RLCs developed for a given year are expected to model the hourly demand patterns of that year. These RLCs are useful for planning in resource constrained electricity systems and in situations where it is required to know the time variations in demand (e.g. supply-demand matching, seasonal scheduling of hydro plants and maintenance scheduling). RLCs are also useful in identifying the factors influencing variations in demand. This approach will overcome the limitations of current method of representation in the form of static and aggregate annual load duration curves. iv. A new term, "non-supply of electricity" has been introduced in this thesis. A brief overview of non-supply presented here includes reasons for non-supply, type of non-supply, methods to estimate cost of non-supply and factors influencing these estimates. v. The integrated mixed integer programming model developed in the study has been demonstrated as a planning tool for- • Optimal hourly and seasonal scheduling of various existing supply, non-supply and new supply options • Estimation of supply shortages on a representative hourly basis using the information on resource constraints • Effectively planning non-supply of electricity through appropriate power/energy rationing methods • Estimation of the need for the new capacity additions both to bridge the existing gap and to take care of increase in future demand levels • Optimal filling of gaps between demand and supply on a representative hourly basis through new supply of electricity • Optimally arriving at the judicious mix of public and private capacity additions • Studying the impacts of private capacity on the existing and new public sector capacity, and on the consumers • Optimally verifying the feasibility of integrating the captive generation with the total system vi. The demand analysis using RLCs helped to bring out the differences in demand patterns with and without constraints, impacts of constraints on preferred pattern of electricity consumption, success of non-supply options in both reducing the demand levels and greatly disturbing the electricity usage patterns. Multifactor ANOVA analyses results showed that the logically obtained factors accounted for maximum variations in demand at very high significance levels. vii. A comparison of optimal (represented by optimal predicted RLCs) and actual (reflected by actual RLCs) practices facilitated by the model showed that the actual practice during constrained years is highly ad hoc and sub-optimal. viii. The results of the scenario analyses showed that it is more economical to have some amount of planned rationing compared to having a more reliable system, which does not allow non-supply of electricity. ix. The scenarios, which analysed the impacts of high guarantees offered to the private sector, showed the negative impacts of these in terms of reduced utilization of both the existing and new public capacity. x. Generation expansion plans till the year 2010-11 are developed using the results of various kinds of scenario analyses. Two groups of year-wise generation expansion plans are generated, one with only public sector capacity additions and the other with private sector participation. xi. The impacts of privatization of capacity additions are studied from the point of view of the utility and consumers in terms of expected increase in cost of purchase of electricity and tariffs. xii. The analyses are also made for developing some insights into fixing the availability and plant load factors for the private capacity. Based on the analysis, the recommended range for plant utilization factor is 72.88 - 80.57%. We believe that the integrated approach presented and the results obtained in this thesis would help utilities (both suppliers and distributors of electricity) and governments in making rational choices in the context of resource constrained systems. The results reported here may also be used towards rationalization of Government policies vis-a-vis tariff structures in the supply of electricity, planning new generation capacity additions and effective rationing of electricity. It is also hoped that the fresh approach adopted in this thesis would attract further investigations in future research on resource constrained systems.
176

Dynamics of Invariant Object Representations in the Monkey Inferotemporal Cortex

Ratan Murty, Naredle Apurva January 2016 (has links) (PDF)
Vision is computationally challenging because objects in the real world can change in size, position, viewpoint etc., and therefore cast a myriad images on the retina. Viewpoint changes are particularly challenging because new features can appear or disappear and existing features can be stretched or compressed. Even though humans are adept at recognizing objects across changes in viewpoint, the underlying neural representations are poorly understood. The goal of this thesis is to investigate viewpoint invariant object representations in the brain using recordings of single neurons in monkey visual cortex, and using behavioural experiments in humans. This thesis summarizes the results from a series of six experiments in which we recorded the responses of single neurons in the monkey inferior temporal cortex, an area critical for object recognition. In Experiment 1, we recorded neural responses to objects across two views and elucidated the dynamics of viewpoint invariance and the factors that modulate it. We observed a dramatic transition from view dependence in the early part of the neural response to view invariance in the later part. In Experiment 2, we investigated the effect of silhouetting and inversion on view invariance. In Experiment 3, we generalized our findings to multiple viewpoints and characterized view invariance for impoverished non-generic viewpoints and mirror views. In Experiment 4, we compared the magnitude and dynamics of viewpoint invariance with other known identity-preserving transformations such as size, position and rotation. In Experiment 5, we demonstrate that IT neurons potentially encode object features even after they rotate out of view. In Experiment 5, we demonstrate a generalization of view invariance, whereby neurons can decouple patterns across non-rigid surface changes. Taken together, our results reveal a dynamic picture of how view invariant representations are constructed in the brain to enable complex perceptual inferences.
177

Temperature Coefficients and Thermal Uniformity Mapping of PV Modules and Plants

January 2016 (has links)
abstract: The operating temperature of photovoltaic (PV) modules is affected by external factors such as irradiance, wind speed and ambient temperature as well as internal factors like material properties and design properties. These factors can make a difference in the operating temperatures between cells within a module and between modules within a plant. This is a three-part thesis. Part 1 investigates the behavior of temperature distribution of PV cells within a module through outdoor temperature monitoring under various operating conditions (Pmax, Voc and Isc) and examines deviation in the temperature coefficient values pertaining to this temperature variation. ANOVA, a statistical tool, was used to study the influence of various factors on temperature variation. This study also investigated the thermal non-uniformity affecting I-V parameters and performance of four different PV technologies (crystalline silicon, CdTe, CIGS, a-Si). Two new approaches (black-colored frame and aluminum tape on back-sheet) were implemented in addition to the two previously-used approaches (thermally insulating the frame, and frame and back sheet) to study temperature uniformity improvements within c-Si PV modules on a fixed latitude-tilt array. This thesis concludes that frame thermal insulation and black frame help reducing thermal gradients and next best viable option to improve temperature uniformity measurements is by using average of four thermocouples as per IEC 61853-2 standard. Part 2 analyzes the temperature data for two power plants (fixed-tilt and one-axis) to study the temperature variation across the cells in a module and across the modules in a power plant. The module placed in the center of one-axis power plant had higher temperature, whereas in fixed-tilt power plant, the module in north-west direction had higher temperatures. Higher average operating temperatures were observed in one-axis tracking as compared to the fixed-tilt PV power plant, thereby expected to lowering their lifetime. Part 3 focuses on determination of a thermal model coefficients, using parameters similar to Uc and Uv thermal loss factors used in PVsyst, for modules of four different PV technologies experiencing hot-desert climate conditions by statistically correlating a year-long monitored data. Thermal models help to effectively quantity factors influencing module temperatures to estimate performance and energy models. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016
178

Mapa da pilosidade H de fios de algod?o em sistemas de fia??o de anel/viajante trados por nitreta??o ? plasma

Melo, Mois?s Vieira de 09 July 2012 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T19:31:01Z No. of bitstreams: 1 MoisesVieiraDeMelo_TESE.pdf: 3298262 bytes, checksum: 6c8131d4ccbb84ead6360566fbd11a1e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-10T23:52:39Z (GMT) No. of bitstreams: 1 MoisesVieiraDeMelo_TESE.pdf: 3298262 bytes, checksum: 6c8131d4ccbb84ead6360566fbd11a1e (MD5) / Made available in DSpace on 2017-03-10T23:52:39Z (GMT). No. of bitstreams: 1 MoisesVieiraDeMelo_TESE.pdf: 3298262 bytes, checksum: 6c8131d4ccbb84ead6360566fbd11a1e (MD5) Previous issue date: 2012-07-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este trabalho experimental mapeou a qualidade de fios de algod?o produzidos em duas ind?strias t?xteis distintas, de acordo com as refer?ncias USTER? para avalia??o da qualidade de um fio. Os resultados das m?dias de pilosidade H de amostras de fios representativas de cada produ??o di?ria foram testados usando ANOVA por meio da ferramenta estat?stica Statgraphics? Centurion XVI. Um mapa de pilosidade H foi projetado e constru?do sistematicamente para avaliar a qualidade de fios de algod?o NE 30/1 cardados malharia produzidos durante toda a vida de viajantes, deslizando continuamente a 28 m/s e 42 m/s em dois filat?rios, com 528 e 1.480 fusos, constituindo dois sistemas, A e B, respectivamente. Ensaios tribol?gicos de abras?o foram projetados e executados em Laborat?rio a 3,5 m/s, exercendo sete n?veis de press?o de contato de Hertz para simular a zona de contato do sistema anelviajante nitretado e analis?-la por Microscopia Eletr?nica de Varredura para identificar mecanismos de desgaste desenvolvidos nos corpos-de-prova. Foram nitretados por duas condi??es distintas de processamento, C e D, lotes de 100 viajantes nitretados, para o sistema de fia??o A e 740 viajantes nitretados (esquemas C e D) para o sistema B, os quais foram ensaiados experimentalmente, para comparar aos resultados da qualidade dos fios de algod?o obtidos pelos viajantes convencionais. Par?metros peri?dicos da Rugosidade Superficial, Rsm, e n?o-perI?dicos, Ra, Rq e Rz, da borda dos viajantes nitretados, ou n?o, na zona de contato com o fio produzido, foram medidos por AFM, Microscopia de For?a At?mica, em duas condi??es, Novos e Desgatados ap?s a sua vida em servi?o. O Mapa de Pilosidade H desenvolvido nesta Tese mostrou ser uma ferramenta ?til para uma ampla visualiza??o da funcionalidade do viajante, da relev?ncia da nitreta??o a plasma e da evolu??o da rugosidade superficial durante a sua vida em servi?o. Os viajantes nitretados a plasma demonstraram um aumento da vida em servi?o de 14 DIAS PARA 63 DIAS e produziram fios de algod?o NE 30/1 cardados malharia com 39% de pilosidades H menor que aqueles obtidos pelos viajantes convencionais que duraram 17 dias em servi?o. / This experimental investigation concerning to cotton yarn quality was conducted in two different textile industries according to USTER? yarn quality benchmarks. The results of the Hairiness H of yarn samples representing each diary production were tested using ANOVA by means of Statgraphics? Centurion XVI statistical tool. A hairiness H map was designed and systematically constructed for evaluate the quality of NE 30/1 Cotton Carded Knitting Yarns produced during all the life of travelers running continuously at 28 m/s and 42 m/s in two ring spinning machines, with 528 and 1,480 spindles, so constituting two systems, A and B, respectively. Tribological abrasion tests were designed and performed in Laboratory at 3.5 m/s in order to simulate Hertzian contact pressures since severe to moderate range for simulate the contact zone of the ring-traveller system and analyze by Scanning Electron Microscopy their main wear mechanisms. Ion nitrided travellers were obtained by two different processing conditions, C and D, to compose lots of 100 nitrided travellers for A spinning machine system and 740 nitrided travellers (C and D schemes) for B system and were experimentally tested in comparison with conventional travellers. Periodical Surface Roughness, Rsm, and Nonperiodical Ra, Rq and Rz parameters of nitrided and conventional travellers, in the Position of Yarn Bath, i.e., the contact zone between the traveller and the yarn, were measured by Atomic Force Microscopy (AFM), in two conditions, new and worn after their service life. The Hairiness H Map developed in this thesis showed is a useful tool for a broad visualization of the traveller functionality, the relevance of its surface treating and the evolution of the surface roughness during its service life. The nitrided travellers demonstrated longer life and they produced NE 30/1 Cotton Carded Knitting Yarns with lower H hairiness that those obtained by conventional travellers.
179

An investigation into the relationship between satisfaction with life and sense of coherence amongst the unemployed

Mankayi, Dolphia Thozama January 1996 (has links)
Magister Commercii (Industrial Psychology) - MCom(IPS) / The present study investigated the relationship between the Sense Of Coherence and Satisfaction With Life amongst the unemployed. The study attempted to test the following hypotheses. 1. People with a high Sense Of Coherence tend to be satisfied with their lives in general. 2. Demographic variables such as age, gender, race and level of education have an influence on the subjects' scores on the Sense Of Coherence and Satisfaction With Life scales. 3. Length of unemployment has an impact on the subjects' Sense Of Coherence and Satisfaction With Life. In this study, subjects were drawn from the Department of Manpower in the Western Cape region. The data were obtained from a sample of 100 participants. Of this 100, 52 were males. Subjects were asked to complete the Sense Of Coherence and the Satisfaction With Life scales. Statistical procedures that were used are Multiple Linear Regression analysis, Product Moment Correlational Co-efficients, Analysis of Variance test (ANOVA) and the Cronbach Alphas of the various scales. It was found that Sense Of Coherence correlated significantly with Satisfaction With Life, thus supporting the first hypothesis. This led to the conclusion that a person with a strong Sense Of Coherence tends to be more satisfied with his/her life. However, a person with a weaker Sense Of Coherence finds it difficult to make sense out of his/her life. It was also found that most of the demographic variables did not reach any statistical significance. The general trend in this sample was that younger people had higher education and had been unemployed for fewer years. In comparison, older people were found to have less education and had been unemployed for more years. It was concluded that formal and informal education system will be necessary to develop and equip both young and older people with the experience and skills to use at work. This study was concluded by the discussion of the implications of the findings and suggestions for future research.
180

Návrh postupu kontroly vybraných součástí revolveru / Design of inspection procedure for selected revolver components

Úlehlová, Eva January 2020 (has links)
The goal of this master’s thesis was design of the inspection procedure for hammer and trigger of the specific revolver model. Thesis was developed in cooperation with the manufacturer of the revolvers. The theoretical part deals with the MSA methodology, which is used to assess acceptability of measurement systems. The practical part describes the current measurement system and performs gage repeatability and reproducibility study. It was confirmed that the current measurement system requires improvement. Subsequently coordinate systems were designed, based on functional features of the hammer and trigger. Automated optical measurements, based on the coordinate systems, were performed. The results from these measurements were again assessed by the gage R&R study. The analysis confirmed improvement of acceptability of the designed measurement systems. Based on these results, it is recommended to apply suggested procedures in practice. Results and recommendations of this master’s thesis can contribute to develop metrology in the company and improve the existing measurement system.

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