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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.
341

Atomistic Modelling of Materials for Clean Energy Applications : hydrogen generation, hydrogen storage, and Li-ion battery

Qian, Zhao January 2013 (has links)
In this thesis, a number of clean-energy materials for hydrogen generation, hydrogen storage, and Li-ion battery energy storage applications have been investigated through state-of-the-art density functional theory. As an alternative fuel, hydrogen has been regarded as one of the promising clean energies with the advantage of abundance (generated through water splitting) and pollution-free emission if used in fuel cell systems. However, some key problems such as finding efficient ways to produce and store hydrogen have been hindering the realization of the hydrogen economy. Here from the scientific perspective, various materials including the nanostructures and the bulk hydrides have been examined in terms of their crystal and electronic structures, energetics, and different properties for hydrogen generation or hydrogen storage applications. In the study of chemisorbed graphene-based nanostructures, the N, O-N and N-N decorated ones are designed to work as promising electron mediators in Z-scheme photocatalytic hydrogen production. Graphene nanofibres (especially the helical type) are found to be good catalysts for hydrogen desorption from NaAlH4. The milestone nanomaterial, C60, is found to be able to significantly improve the hydrogen release from the (LiH+NH3) mixture. In addition, the energetics analysis of hydrazine borane and its derivative solid have revealed the underlying reasons for their excellent hydrogen storage properties.  As the other technical trend of replacing fossil fuels in electrical vehicles, the Li-ion battery technology for energy storage depends greatly on the development of electrode materials. In this thesis, the pure NiTiH and its various metal-doped hydrides have been studied as Li-ion battery anode materials. The Li-doped NiTiH is found to be the best candidate and the Fe, Mn, or Cr-doped material follows. / <p>QC 20130925</p>
342

Authenticating Cultural Tourism: Folk Villages in Hainan, China

Xie, Philip Feifan January 2001 (has links)
Cultural tourism provides opportunities for ethnic minorities to showcase their cultures, customs and heritage. At the same time, it causes a series of tensions and issues of authenticity and commodification have been the subjects of lively debate among tourism researchers. However, little research has been done to date concerning the roles of stakeholders who authenticate cultural resources. This thesis develops a conceptual framework that is employed to enhance understanding of the authenticity of cultural tourism when ethnic Li communities in Hainan Island, China, experience tourism development. Folk villages are used as a significant point of access for investigating the tensions which emerge in authenticating cultural resources. Four key stakeholders are identified: (1) governments; (2) tourism businesses; (3) visitors; and, (4) ethnic communities. Five pairs of yardsticks were developed based upon Swain's (1989) work to examine the issue of authentification. These constructs are: non-commercialization versus commodification, cultural evolution versus museumification, economic development versus cultural preservation, ethnic autonomy versus state regulation, and mass tourism development versus sustainable cultural tourism. The findings suggest that authenticity is relative rather than absolute and, like beauty, is in the eye of the beholder. Therefore, it is necessary to shift from a previous focus on the nature and identification of authenticity to the more tractable question of authentification. The various stakeholders exhibit different positions with respect to the various paradoxes and the tensions that exist between their poles. For example, governments pay more attention on the control of ethnic autonomy whilst tourism businesses prioritize the economic development. Tourists exhibit blurred perceptions of authenticity whilst ethnic minority supports the maintenance of their of culture but gives priority to jobs and remuneration. This thesis demonstrates that it is more useful to evaluate who authenticates and the interests that such claims serve, rather than to adhere to some absolute standard of 'authentic' ethnicity. It makes recommendations for tourism planners, such as ethnic participation in the decision-making process, the development of strategic alliance among tourism stakeholders, and the taking of steps to promote the maintenance of Li culture. It also suggests opportunities for applying this conceptual framework of cultural tourism to other different situations, both within Hainan and elsewhere.
343

Li Yu's Theory of Chinese Drama

Liu, Yo-hsien 24 July 2004 (has links)
Li Yu¡¦s Theory of Chinese Opera Abstract Li Yu (1611-1680) is a renowned Chinese opera writer in the early Qing dynasty. His work ¡§Ten Operas¡¨ features surprising plots and easy-to-understand scripts, criticized as ¡§intended to make common¡¨ and ¡§simple to comprehend¡¨, reflecting his writing attitude and style in developing popular and entertainment culture. This deviates himself from the literary direction of drama (chuanqi) writing since the mid-Ming dynasty. In addition, Li Yu is also a Chinese opera critic. The ¡§script¡¨ and ¡§play act¡¨ sections in his ¡§Xian Qing Ou Ji ¡¨(Journal of Leisure Time) discussed mainly the writing and performing of Chinese operas. The journal was written after the publication of the ¡§Ten Operas¡¨, which can be regarded as a summary of Li Yu¡¦s seasoned experience in writing Chinese operas. The journal is also a main research subject of this study. Literature on Chinese operas in Ming and Qing dynasties is rich. On the format, some focused their discussions in a specific book while some discussions were found scattered in anthologies and critics¡¦ notes. On the content, some examined the stories from historical perspectives, some centered on the wording as well as on tones and singing skills; or some were precise investigations on the development of Chinese opera history. The literature is documented with quite a few unique perceptions on the presentations of Chinese operas. These critiques, even as specific works, only present checklist style discussions. Some greater volumes manage to categorize various works but yet to conclude a coherent theory on Chinese opera. The results are usually unsystematic. Li Yu¡¦s theory is distinguished as having a subjective intension to establish a critique system on Chinese operas. In other words, he intended to construct the foundation and writing principles that ¡§others can follow¡¨ and clearly control the essence and development of Chinese operas. His emphasis of ¡§structure¡¨ in making critiques is the result of fully understanding the ¡§dramatic characteristics¡¨ in Chinese operas. Li Yu presented his theory mainly in the ¡§Xian Qing Ou Ji¡¨ with the ¡§script¡¨ and ¡§play act¡¨ sections, the ¡§script¡¨ section stressed on the writing theory while the ¡§play act¡¨ on the presentation. ¡§Dramatic presentation¡¨ is related to the professionalism of actors, not judged by writers¡¦ imagination, thus there are not many discussions on the performance. Li Yu doubled himself as writer and director and developed a system of perception and opinions of his own towards performing Chinese operas. Comparing his writing and presenting Chinese operas, the latter is weaker in depth than the former. Some of the discussions on presentation focus on how to handle scripts on stage and can be regarded as the extension of script writing. Therefore this study is led to focus on Li Yu¡¦s writing. Although Li Yu intended to establish a theory and principle of Chinese opera writing in the ¡§Script section of the Xian Qing Ou Ji¡¨, he only managed to reinforce the importance of the ¡§structure-first¡¨ principle and categorized rhetoric system, tonal pattern, rhyme scheme, conversation and humorous acts with the supplementary discussions of Chinese operas¡¦ ¡§forms¡¨. His categorization seems yet to reach a literature theory defined by modern literary norms. Actually Li Yu produced versatile discussions on Chinese operas. Some of his discussions are related to the fundamental definition, characteristics and functions of Chinese operas. Some belong to the construct of literary principles of Chinese opera. Some are the exploration of the principles and practical skills of Chinese opera writing. Furthermore, there is some comment on some specific works, as well as the discussion of different presentation styles in terms of the development in literary history. Li Yu made a clear intension in constructing the theory of Chinese opera, yet there is quite some space for adjustment in certain areas. Thus this study tries to integrate and summarize Li Yu¡¦s theory on Chinese opera, in a hope of re-constructing and re-translating from modern literary perspectives for eliciting more meaningful implications. During the process, the most important task is to analyze and formulate a theory structure on Li Yu¡¦s perspectives as three major aspects: fundamental theory of Chinese opera, theory of writing Chinese opera and theory of presenting Chinese opera. Fundamental theory of Chinese opera discusses the basic features of Chinese opera as the fundamental basis to construct theories on writing and presentation. These theories also project that his emphasis on the special formulation of Chinese operas and stagecraft. These distinguish him from other theories on Chinese opera in his contemporary era. This study develops as the following structure: Chapter one ¡§Introduction¡¨ states the research motives, scope, methodology and thesis summary in addition to the description of Li Yu¡¦s life and his literary achievements. Chapter two ¡§General Discussion¡¨ explores Li Yu¡¦s fundamental theory of Chinese opera, including the discussions on the artistic characteristics, position of Chinese operas in literature, the essence of Chinese operas, core values in appreciating Chinese operas and functions of Chinese operas ¡Ketc. Chapters three to seven are on theory of Chinese opera writing. Principles and standards in writing Chinese operas are discussed in terms of specific elements that compose Chinese operas. Chapter three ¡§Plot¡¨ redefines viewpoints on the structure in Li Yu¡¦s theory of Chinese opera. Chapter four ¡§Format¡¨ describes the regular formation of traditional Chinese opera presentation after the discussion on structure because set formation results in certain impact on the presentation. Chapter five ¡§Characters¡¨ is on the roles in Chinese opera. Li Yu embedded character formation in the design of plot structure, without independent character theory. The chapter is limited to the relationship among the language of characters, character descriptions and roles. Chapter six ¡§Language¡¨ discusses the common features of opera languages: rhymes and scripts, including the characteristics of representatives in Chinese operas and the standard the opera language should have. Chapter seven ¡§Rules of Tones and Rhymes¡¨ is divided as rhyme scheme and tone patterns with rhyme scheme as the main theme for discussion. The chapter also establishes the common principles of ¡§rule abiding¡¨ and proposed concrete suggestions on handling the rhymes and tones. Finally the thesis discusses Li Yu¡¦s theory of Chinese operas presentation in terms of scripts processing before performance, actor training and guiding and stage presentation. These concluded chapter eight ¡§Performance¡¨. It is hoped, through this thesis, to establish a specific theory structure of Li Yu¡¦s works on Chinese opera.
344

Study on Estimation of Intelligent Residual Capacity of Li-ion Batteries

Lai, Shih-Jung 19 October 2004 (has links)
This research proposes a method for estimating the residual capacity of Li-ion batteries. The charging and discharging characteristics of Li-ion batteries are investigated and analyzed by a battery test system. The measurement of the initial capacity is based on the improved open-circuit voltage measurement, which compensates the effects of battery aging and self-discharging. The measurement of the used capacity is based on the improved coulomb counting measurement, which compensates the effects of output current and environmental temperature. The designed system provides various functions for battery charging and discharging, battery voltage measuring and recording, battery capacity estimation and calculation, and the log files can be used for further battery characteristics analysis.
345

Research and Development of a Smart Li-Battery Management System

Hung, Yu-Huan 29 June 2005 (has links)
This research proposes a smart battery management system applied to Li-Battery. The system not only can monitor the batteries for all kinds of parameters but also modify them by users. Besides, in estimating the residual capacity of Li-ion batteries, an automatic measurement platform is set up in order to record the data of Li-battery in different kinds of charge-discharge condition and to analysis the characteristics. In monitoring used battery capacity, Modified-Coulomb-Measuring method is proposed and it can accurately estimate the residual capacity according to the effect of output current and environment temperature. In addition to estimate the residual capacity accurately, Smart Battery System can record the information of Li-batteries over a long period of time, and the log files can be used for further battery characteristics analysis.
346

none

Haung, Mei-Lan 11 July 2005 (has links)
none
347

The Patriarchal Structure, Female Consciousness-raising and Female Subjectivity in The Peony Pavilion¡X¡XTake Example by Tu Li-Niang

Lan, Yu-Chin 01 August 2001 (has links)
none
348

none

Wu, Wan-jung 26 July 2008 (has links)
none
349

A Study of Village Chiefs Role: A Case Study of An-Shun Li

Chang, Kuei-chen 29 July 2008 (has links)
Village chiefs¡¦ role has been facing great impact and challenge ever since the transition of society, development of information, raise of education level and popularity of communitarianism. Therefore, how village chiefs¡¦ legal position should be set and integrate with village officers as well as community development have been brought into discussion in recent years. While gaps do exist between current academic study and practical operation, this study centers on village chiefs¡¦ position with the case of An-Shun Li of Kaohsiung City for further study. The exploration of literature is divided into three parts: role theory, village chiefs¡¦ position and village systems, and the relationship between village chiefs and community development. Literature review, in-depth interview, and participants¡¦ observation are adopted as research methods. With the concept of status, role expectation, role conflict and role performance in role theory, the study explores the interaction between village chiefs and other connecting village officers, analyzes the problems that chiefs¡¦ encounter under current legal system and then generalizes the role current chiefs should play. The research finds that the biggest difference between current and traditional chiefs is that the role they play as citizens¡¦ participation navigators and community development managers. While government is examining and adjusting village controlling area and government-assigned chief policy, it is advised that concrete solution to be proposed for individual cases which require specific environment. The regulation of village chiefs is wished to become better in the future. A new organization is looking forward to be setting up as a mediator between village chief and community development organization to deal with community affairs, thus to make the local system in line with modern society demands.
350

Onboard Impedance Diagnostics Method of Li-ion Traction Batteries using Pseudo-Random Binary Sequence

Savvidis, Charalampos, Geng, Zeyang January 2015 (has links)
Environmental and economic reasons have lead automotive companies towards the direction of EVs and HEVs. Stricter emission legislations along with the consumer needs for more cost-efficient and environmental friendly vehicles have increased immensely the amount of hybrid and electric vehicles available in the market. It is essential though for Li-ion batteries, the main propulsion force of EVs and HEVs, to be able to read the battery characteristics in a high accuracy manner, predict life expectancy and behaviour and act accordingly. The following thesis constitutes a concept study of a battery diagnostics method. The method is based on the notion of a pseudo-random binary signal used as the current input and from its voltage response, the impedance is used for the estimation of parameters such as the state of charge and more. The feasibility of the PRBS method at a battery cell has been examined through various tests, both in an experimental manner at the lab but also in a simulation manner. The method is compared for validation against the electrochemical impedance spectroscopy method which is being used as a reference. For both the experimental and the simulation examinations, the PRBS method has been validated and proven to work. No matter the change in the parameters of the system, the method behaves in a similar manner as in the reference EIS method. The level of detail in the research and the performed experiments is what makes the significance of the results of high importance. The method in all ways has been proven to work in the concept study and based on the findings, if implemented on an EV’s or HEV’s electric drive line and the same functionality is observed, be used as a diagnostics method of the battery of the vehicle.

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