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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.
71

Finite Element Analysis and Genetic Algorithm Optimization Design for the Actuator Placement on a Large Adaptive Structure

Sheng, Lizeng 29 December 2004 (has links)
The dissertation focuses on one of the major research needs in the area of adaptive /intelligent/smart structures, the development and application of finite element analysis and genetic algorithms for optimal design of large-scale adaptive structures. We first review some basic concepts in finite element method and genetic algorithms, along with the research on smart structures. Then we propose a solution methodology for solving a critical problem in the design of a next generation of large-scale adaptive structures -- optimal placements of a large number of actuators to control thermal deformations. After briefly reviewing the three most frequently used general approaches to derive a finite element formulation, the dissertation presents techniques associated with general shell finite element analysis using flat triangular laminated composite elements. The element used here has three nodes and eighteen degrees of freedom and is obtained by combining a triangular membrane element and a triangular plate bending element. The element includes the coupling effect between membrane deformation and bending deformation. The membrane element is derived from the linear strain triangular element using Cook's transformation. The discrete Kirchhoff triangular (DKT) element is used as the plate bending element. For completeness, a complete derivation of the DKT is presented. Geometrically nonlinear finite element formulation is derived for the analysis of adaptive structures under the combined thermal and electrical loads. Next, we solve the optimization problems of placing a large number of piezoelectric actuators to control thermal distortions in a large mirror in the presence of four different thermal loads. We then extend this to a multi-objective optimization problem of determining only one set of piezoelectric actuator locations that can be used to control the deformation in the same mirror under the action of any one of the four thermal loads. A series of genetic algorithms, GA Version 1, 2 and 3, were developed to find the optimal locations of piezoelectric actuators from the order of 10<SUP>21</SUP> ~ 10<SUP>56</SUP> candidate placements. Introducing a variable population approach, we improve the flexibility of selection operation in genetic algorithms. Incorporating mutation and hill climbing into micro-genetic algorithms, we are able to develop a more efficient genetic algorithm. Through extensive numerical experiments, we find that the design search space for the optimal placements of a large number of actuators is highly multi-modal and that the most distinct nature of genetic algorithms is their robustness. They give results that are random but with only a slight variability. The genetic algorithms can be used to get adequate solution using a limited number of evaluations. To get the highest quality solution, multiple runs including different random seed generators are necessary. The investigation time can be significantly reduced using a very coarse grain parallel computing. Overall, the methodology of using finite element analysis and genetic algorithm optimization provides a robust solution approach for the challenging problem of optimal placements of a large number of actuators in the design of next generation of adaptive structures. / Ph. D.
72

Chemical Compositions of Edamame Beans and Valorization of Edamame Shells

Yu, Dajun 23 January 2023 (has links)
Edamame is becoming more popular in the U.S. due to its high nutritional value and potential health benefits. However, more than 70% of edamame is imported from outside of the U.S. Therefore, developing elite edamame genotypes is critically desirable to increase the domestic production of edamame in the U.S. Genotype, planting location, and harvest time play essential roles in the chemical composition of edamame, which further decide edamame's nutritional value and sensory characteristics. Therefore, the first goal of this study is to comprehensively evaluate the chemical composition of edamame genotypes grown in different locations. Ten selected edamame genotypes were grown in three locations in the U.S. - Whitethorne, Virginia (VA), Little Rock, Arkansas (AR) and Painter, VA. Sugars, alanine, protein, oil, neutral detergent fiber (NDF), starch, ash, and moisture contents, were comprehensively analyzed. The results showed that location had significant effects on all chemical components of edamame with p < 0.05. Compared to Painter and Little Rock, genotypes planted in Whitethorne had higher averaged free sucrose, fructose, glucose, raffinose, stachyose, and starch contents and total sweetness. The highest crude protein and oil contents were found on edamame planted in Painter, while Little Rock produced edamame with the highest free alanine, ash, and moisture contents. Genotype significantly affected chemical compositions except for NDF and raffinose. Therefore, planting location and edamame genotype should be considered when producing elite edamame for the U.S. market. Chemical composition changes with the development of edamame; therefore, harvest time is essential for harvesting high-quality edamame. The second objective of this study is to quantify the changes in both physical and chemical properties of edamame over bean development and apply a combined spectroscopy and machine learning (ML) technique to help determine the optimal harvest time. Physical and chemical properties were analyzed for edamame harvested at R5 (beginning seed), R6 (full seed), and R7 (beginning maturity) growth stages, and the spectral reflectance (360 – 740 nm) of edamame pods was measured using a handheld spectrophotometer. The samples harvested at different stages were labeled as 'early,' 'ready,' and 'late.' At R6, pod/bean weight and pod thickness reached the peak and then stayed stable, while sugar, alanine, starch, and glycine also peaked at R6 but declined afterward. The spectra-based ML method had high accuracy (0.95) when classifying 'early' and 'late' edamame, and the accuracy was 0.87 for classifying 'early' and 'ready' edamame. These results indicated that this spectra-based ML method could determine the optimal harvest time of edamame. Food waste and loss not only lead to economic loss but also significant greenhouse gas emissions. With edamame food/snack production increasing, edamame shells, the low-value byproduct from this processing, will potentially threaten the environment. Similar to other food processing byproducts, edamame shell is rich in dietary fiber (DF). However, the high concentration of insoluble dietary fiber (IDF) limits its application as a food additive. Therefore, extraction/modification processes are needed to convert IDF to soluble dietary fiber (SDF) and improve the properties of edamame shell-derived DF. Ball milling is one of the most efficient techniques to break down biomaterials into sub-micro-level particles. Citric acid, as a natural and safe food additive, can help break down cell walls and improve the dissolution of SDF by ionizing the hydrogen ions with carboxyl groups. Therefore, the third objective of this study is to develop a process that combines ball milling and citric acid treatments to produce SDF from edamame shells. We investigated different treatment parameters, including different citric acid concentrations, treatment temperatures and time, and the application of ball milling. To determine if the combined treatment can potentially improve the properties of the produced SDFs, we characterized the physicochemical, morphological, structural, rheological, thermal, and functional properties of SDFs produced at different conditions. The results showed that the highest SDF yield (19.5%) was found when the edamame shells were pretreated by a ball mill. In addition, the combined citric acid and ball milling treatment altered several properties of the produced SDFs, including particle size, morphology, and crystallinity. Moreover, ball milling treatment led to a higher exothermic temperature peak of SDF indicating better thermal stability. All produced SDFs significantly elevated the production of short-chain fatty acids during in vitro fermentation (compared to the control fermentation) which indicated their potential benefits of promoting gut health. Overall, we demonstrated that ball-milling-assisted citric acid processing can be an effective green technique to produce SDF from edamame shells. The SDF produced from edamame shells can be regarded as a promising and novel ingredient with great potential to be used in foods. / Doctor of Philosophy / Edamame is becoming increasingly popular among consumers in the U.S. because it is nutritious and good for health. However, more than 70% of edamame in the U.S. market is imported from other countries. Therefore, having more edamame genotypes that adapt to the growing environment in the U.S. will help increase the domestic production of edamame. Genotype and planting location are essential in deciding edamame's nutritional value and taste. Therefore, the first objective of this study is to comprehensively understand the nutritional value of different edamame genotypes grown in three planting locations. The results showed that both location and genotype affected the nutritional values of edamame, indicating that planting location and edamame genotype should be considered when developing better edamame for the U.S. market. Nutritional value and sweetness change with the growth of edamame beans. Therefore, harvest time is crucial for harvesting edamame with better nutrition and taste. This study's second objective is to observe edamame's nutritional factors and sweetness over bean development and develop a method using a handheld colorimeter to help determine the optimal harvest time. The results showed that the edamame harvested at the full seed stage (called R6) is the sweetest compared to the other two stages. In addition, the handheld colorimeter combined with the machine learning technique showed high accuracy in separating 'early' and 'late' harvested edamame and 'early' and 'ready' harvested samples. These results indicated that the combination of colorimeter and machine learning could help determine the optimal harvest time of edamame. Food waste and loss not only lead to economic loss but also significant greenhouse gas emissions. Edamame shells, the low-value byproduct from edamame snack/food processing, will potentially threaten the environment if edamame consumption keeps increasing. Like other food waste, edamame shell is rich in dietary fiber (DF). Therefore, it is vital to find a way to recover the DF in edamame for other applications. Ball milling is a green technology that can efficiently break down big particles. Citric acid is a natural and safe food additive and can help break down insoluble cell walls. Therefore, this study aims to produce soluble dietary fiber (SDF) from edamame shells using ball milling and citric acid. We proved that ball-milling assisted acid processing can be an environmentally friendly method to produce edamame shell SDF which can potentially be used as a suitable food ingredient.
73

旗艦廠商投資母國區位選擇之研究

吳秉鴻, Wu, Ping Hung Unknown Date (has links)
綜觀台灣過去數十年來的產業經濟發展歷程,在國際間有許多正面的評價,稱之為「台灣經濟奇蹟」。在政府政策致力於塑造有利於科技產業發展的環境下,製造業為台灣產業帶來重大的貢獻,當我國不同的產業類別之製造業發揮其優勢競爭力的同時,亦使得台灣地區北、中、南三大區域發展出各自獨特且具有潛力的製造業特性。 事實上,區域產業特性與賦能之優劣將可透過區域中廠商與行動者的活動來表現,尤其是區域中的模範角色,是檢視區域中有無可學習的模範者和模仿其整體投資階段過程的重要指標,對於區域內外企業進駐和設立工廠的組織決策相當重要(Bandura, 1986; van Praag, 1996; Kriegesmann, 1999; Fornahl, 2003)。這樣的仿效行為將指向區域中旗艦廠商投資設廠區位選擇與組織決策行動,換句話說,旗艦廠商(flagship firm)是區域發展中重要的模範角色(role model)(Fornahl, 2003),而其區位選擇與組織決策行為對於區域發展將佔有舉足輕重的地位。另一方面,過去傳統投資區位選擇的討論,多論及單一廠商設立工廠在地理空間的決策行為。然而本研究認為旗艦廠商多工型工廠(multiplant)的特性在組織決策上的區位選擇行為,面對各區域經濟與產業發展特性的差異,應有不同於過去文獻與理論的考量。 是故,本研究透過天下雜誌公佈台灣地區2007年製造業1000大廠商,聚焦台灣地區製造業旗艦廠商面對投資母國區位選擇的考量,透過旗艦廠商在台投資多工型工廠歷程決策之整體分析,藉由投資時間與空間區位,以及廠商組織型態面向的討論,了解台灣地區旗艦廠商投資多工型工廠於母國區位選擇之因素。透過多項羅吉特模型的實證研究,本研究歸納研究成果,提出下列政策建議: 一、推動企業總公司在地化發展,有助區域內旗艦廠商再投資母國之活動 二、透過旗艦廠商在區域內之投資經驗,引導再投資活動,以利區域發展 三、區域內產業特性強化與升級,以加強區域高科技產業支撐力 四、科學工業園區與區域內科技基礎產業優勢分進合擊,提升產業關聯性 五、提升區域總體經濟發展,有助於吸引區域內高科技產業再投資之活動
74

Nálezové kontexty etruských spon / Finding contexts of etruscan fibulae

Eštoková, Petra January 2014 (has links)
This thesis is dealing with Villanovan and Etruscan fibulae, their typology, chronology and location within the tombs of necropolises of Veii. The aim of this thesis is to point to the occurance of fibulae in different time horizonts, to show their development and to compare the necropolises of Veii with other specific locations in Italy. The thesis focuses on evaluation of development and relations of the components of funerary equipments, localy and outside the area of Veii as well. Based on the data collected it is possible to point out the similarities of the necropolises of Veii and to compare them with more distant locations in Italy. Key words: Veii, necropolis, fibulae, typology of fibulae, manufacture, funerary contexts, relations with paralel locations.
75

Souvislost mezi sociálním prostředím a konvertitou k extremismu / Coherence between social environment and conversion to Extremism

Mikšíková, Renata January 2016 (has links)
The Graduation work "Coherence between social environment and conversion to extremism" sets forth an insight into the issue of extremism and socially excluded locations.The aim of the work was to find relations between these two notions. The extremist scene in the Czech Republic was described in details as well as the crime connected to extremism, and psychological expert account of extremist crime perpetrators. Further, the situation of socially excluded locations was introduced, their increase within recent years, and especially problems of children growing up in these locations. Also were mentioned possible mental deprivations, which may occur at children from these location. In the practical part, 37 directed interviews were carried out with Czech extremist parties (both right and left - wing) members. Based on these interviews a conclusion was reached, whether life in socially excluded location may influence an individual's eventual conversion to extremism.
76

Zmapování vhodných pražských parků a cyklostezek pro volnočasové aktivity se zaměřením na výuku in-line bruslení pro žáky 1. stupně / Mapping appopriate Prague parks and trails for leisure activities focused on in-line skating for the pupils of a primary school

Suchý, Jan January 2011 (has links)
In the introduction of theoretical part, a sport discipline In line skating is described. Legislative aspect together with use of cycle paths is considered.The second chapter describes system of cyclopaths in the cities. Following chapters are describing the concept of parks and cyclopaths development in the rural area until 2020. Next, the work establishes criteria for evaluation of locations discussed in charter 5. Theoretical part of this work discusses in chapter six general rules for cyclopaths and park use. In chapter seven traffic signalization and in line skaters' equipment are discussed. Further chapters focus on sport and safety equipment. In the end of theoretical part of chapter ten and eleven I comment on particularities of in line skating education for children 7- 10 years old. Practical part describes mapping and evaluation of 10 selected cyclopaths located on the left side of Vltava River and close surroundings in chapter 12-13. Chapter 14 is dedicated to in-line skating and its categories. In the end of the practical part, the structure and methodology of teaching lesson of in-line skating is depicted together with description of basics of in line skating. Appendix consists of graphical comparison of results from public survey Keywords In-line skating, skating lessons, mapping of...
77

Análise da tolerância à ferrugem asiática em dialelo parcial com genitores transgênicos e convencionais de soja / Analysis of the tolerance to Asian rust in partial diallel with transgenic and conventional soybean parents

Nazato, Felipe Maniero 14 January 2015 (has links)
Essa pesquisa buscou comparar as tecnologias transgênica (soja RR e manejo com glifosato) e convencional (soja e manejo convencionais) quanto à maior tolerância à ferrugem asiática (Phakopsora pachyrhizi) e obtenção de genótipos promissores para produtividade de grãos (PG) e tamanho das sementes (representado pelo peso de cem sementes, PCS). Foram avaliadas 200 progênies F2:5 e F2:6 oriundas de dois dialelos parciais 5 x 2, ambos com cinco genitores de alta produtividade de óleo (USP 70.108, USP 70.010, USP 70.113, USP 70.007 e USP 70.042) em cruzamentos com: (1) duas cultivares elites convencionais (BRS 133 e Conquista); (2) suas versões essencialmente derivadas transgênicas (BRS 245 RR e BRS Valiosa RR). Os experimentos envolveram: a) dois manejos com herbicidas, manejo convencional para soja convencional e manejo com glifosato para a soja RR; b) dois manejos de fungicidas, sendo um experimento com aplicações sucessivas de Opera & Nativo (O&N, para controle da ferrugem e das doenças de final de ciclo, DFC) e outro experimento com aplicações de Derosal para controle apenas das DFC. O efeito da ferrugem para cada genótipo foi expresso pela taxa de reação da ferrugem sobre a produtividade (FP) e o tamanho das sementes (FT), calculados pelas diferenças entre médias ajustadas de PG e PCS nos dois experimentos com fungicidas. As comparações foram feitas em análises de variância, testes de médias e de parâmetros de capacidade de combinação. O controle da ferrugem com fungicidas (O&N) resultou em maiores médias de PG e PCS. Houve grande variação entre os efeitos de capacidades geral e específica, com destaque dos genitores USP 70.108, USP 70.010 e BRS 133 para PG e FP. O genitor mais divergente e com dominância positiva para PG foi USP 70.042. As duas tecnologias foram numericamente semelhantes para tolerância à ferrugem (FP e FT). A tecnologia convencional apresentou a vantagem de ser estatisticamente mais produtiva (PG e PCS) do que a tecnologia transgênica. Por outro lado, a tecnologia transgênica tem a vantagem de ter uso mais fácil e menor custo de cultivo aos produtores. / This research aimed to compare the performance of transgenic (RR soybean and management with glyphosate) and conventional (conventional soybean and herbicides) technologies for tolerance to rust (Phakopsora pachyrhizi ) and obtaining promising genotypes for seed yield and size (represented by the weight of one hundred seeds, PCS). A total of 200 progenies were evaluated in F2:5 and F2:6 generations; these progenies were obtained in two partial diallel 5 x 2, both involving five parents with high oil yield (USP 70.108, USP 70.010, USP 70.113, USP 70.007 and USP 70.042) in crosses with: (1) two elites conventional cultivars (BRS 133 and Conquista); (2) their essentially derived transgenic versions (BRS 245 RR and BRS Valiosa RR). The experiments involved: a) two managements with herbicides: conventional management for conventional soybean and management based in glyphosate herbicide to RR soybean; b) two managements with fungicides: an experiment with successive applications of Opera & Native (O&N, fungicides that control rust and late season leaf diseases, DFC), and another experiment with Derosal applications (fungicide that controls only DFC). The effect of rust for each genotype was expressed by the rate of reaction to rust on seed yield (FP) and on seed size (FT) as calculated from the differences in seed yield (PG) and seed size (PCS) between adjusted means in the two experiments with different fungicides. The soybean genotypes were compared by analysis of variance, multiple comparisons and parameter estimation of combining ability. In general, the control of rust with fungicides (O&N) resulted in higher means of PG and PCS. There was great variation among the effects of general and specific combining abilities, with major outstanding of USP 70.108, USP 70.010, and BRS 133 parents for PG and FP. The parent USP 70.042 was the most divergent and showed positive dominance for PG. Both technologies were numerically similar for FP and FT. The conventional technology has the advantage to be statistically more productive (PG and PCS) than transgenic technology. However, the transgenic technology has the advantage to be easier to use and less expensive to soybean producers.
78

The impact on knowledge spillovers on MNE ownership modes and sub-national locations : evidence from India

Konwar, Ziko January 2013 (has links)
The thesis investigates how FDI intra-industry spillovers are affected by MNE ownership modes and sub-national locations. A conceptual framework is developed which utilises IB theories to propose how MNE ownership modes and sub-national locations are likely to matter for FDI spillovers. The research propositions are explored quantitatively using an unbalanced firm-level panel dataset of 1624 Indian manufacturing firms (1991-2008) with 5203 firm-year observations. The model estimation is carried out in STATA 13.0 in two stages; firstly, by using semi-parametric (Levinsohn-Petrin) method to derive the dependent variable (TFP of domestic firms); and secondly, by using fixed effects model estimated in first-differences to relate TFP of domestic firms' with different measures of foreign presence. Results from the first model reveal that WOSs and MAJVs have positive spillover effects whereas MIJVs have negative spillover effects in the Indian manufacturing sector. The second model finds that the net spillover effect in non-metropolitan regions is higher than in metropolitan regions. The thesis discusses the possible major policy implications of the results and considers possible reasons for the differences in the spillovers for different ownership modes and sub-national locations.
79

Zmapování vhodných pražských parků a cyklostezek pro volnočasové aktivity se zaměřením na výuku in-line bruslení pro žáky 1. stupně / Mapping appopriate Prague parks and trails for leisure activities focused on in-line skating for the pupils of a primary school

Suchý, Jan January 2011 (has links)
In the introduction of theoretical part, a sport discipline In line skating is described. Legislative aspect together with use of cycle paths is considered.The second chapter describes system of cyclopaths in the cities. Following chapters are describing the concept of parks and cyclopaths development in the rural area until 2020. Next, the work establishes criteria for evaluation of locations discussed in charter 5. Theoretical part of this work discusses in chapter six general rules for cyclopaths and park use. In chapter seven traffic signalization and in line skaters' equipment are discussed. Further chapters focus on sport and safety equipment. In the end of theoretical part of chapter ten and eleven I comment on particularities of in line skating education for children 7- 10 years old. Practical part describes mapping and evaluation of 10 selected cyclopaths located on the left side of Vltava River and close surroundings in chapter 12-13. Chapter 14 is dedicated to in-line skating and its categories. In the end of the practical part, the structure and methodology of teaching lesson of in-line skating is depicted together with description of basics of in line skating. Appendix consists of graphical comparison of results from public survey Keywords In-line skating, skating lessons, mapping of...
80

Ve stínu Lidic - srovnání proměn paměti obcí vyhlazených v období Protektorátu Čechy a Morava / In the Shadow of Lidice - Comparison of changes in the memory of the villages exterminated during the Protectorate of Bohemia and Moravia

Kyliášová, Sandra January 2019 (has links)
This diploma thesis is focused on changes of perception of selected municipalities, which were affected by extermination action during the existence of the Protectorate of Bohemia and Moravia. Unlike Lidice and Ležáky, however, they are not so well-known today. For comparison, I chose five Moravian villages and settlements, of which Zákřov and Javoříčko lay in the Olomouc, Ploština, Prlov and Vařákovy paseky were in the area of Wallachia. The introductory part is devoted to the theory of memory, focusing on collective memory and memory space with inspiration from sociology and history authors. Namely Maurice Halbwachs, Pierre Nora, Jan Assmann and Miroslav Hroch in Czechia. This is followed by a chronological summary of historical developments in individual localities, from their origin, through their destruction to development after World War II. The main passage of this work is an overview of professional, non-fiction and, rarely, fictional literary sources and media sources that have created memory of these places since the end of World War II to the present day. These sources show a political and social shift between periods of time, including propaganda based on the omission of some information or the fabrication of ideologically burdened theories. It also includes a final comparison of...

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