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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.
251

Mathematical modelling and improvement of operating practices of sun drying of rice : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Phylosophy [i.e. Philosophy] at Massey University

Meas, Pyseth Unknown Date (has links)
In Cambodia, sun drying of rice has always been of great importance for preserving rice. The main goal of this study was to find the conditions for sun drying that maximise the throughput while minimising quality loss. A whole-bed approach was taken to investigate the conditions of the grain and the air at different layers during the drying process. Seven sets of sun-drying experiments were conducted in Cambodia using a range of methods practiced by rice farmers. These methods included drying with different bed depths (2 to 6 cm), with the bed on different pads (water-proof tarpaulin, mat, net, polystyrene or rice husk), and with different bed tempering methods (stirring regularly or shading and/or covering the bed around midday) for four Cambodian rice varieties (Pka Knhey, CAR11, Masary and IR66). The grain temperature was found to be more affected by the solar intensity than the temperature of the ambient air. Fastest drying was achieved when the bed was thin, less compacted, stirred regularly but not shaded or covered around midday, dried on a pad which allows some air and moisture movement and with high or strong solar intensity. Only the mechanical impact (MI) and milling tests of the rice quality provided useful results. Higher quality was found for grain that was dried in thin beds, stirred regularly, shaded with or without covering around midday and dried on pads with less air circulation. Among the methods used to determine the glass transition temperature of the grain, only the Differential Scanning Calorimetry method gave meaningful results. The glass transition temperature data were highly variable but generally decreased with increasing moisture content and compared quite well with the published glass transition temperatures for other varieties of rice. To provide additional detail on the local conditions within the bed, to better understand the drying process and the interactions between variables and to predict alternative parameters that might be used to correlate with the head rice yields (HRYs), a mathematical model for heat and moisture transport within the bed was developed. The model covered all the drying methods/conditions studied experimentally. A lumped parameter approach to energy and mass transfer in individual kernels was used in the bed model. The model was validated against experimental data. The predicted drying time, temperatures, moisture contents and water activities (relative humidity of the air within the bed) were found to compare very well with the experimental data except when a polystyrene pad was used. The model proved to be a very good mechanistic tool with advantages of simplicity and practical accuracy in the design and management of the sun drying system. A number of parameters related to postulated grain damage mechanisms were derived from the predicted conditions within the bed during drying. The best predictors of the grain quality were found to be rewetting the kernels when the grain is bulked (especially when the kernels are partly below and partly above critical moisture content) grain temperature and distance from the glass transition temperature line. It was concluded that in order to get the fastest drying conditions rice should be sun dried with thin bed, stirring, not shaded or covered around midday and dried on a pad with air circulation. For the highest quality grain, that is grain which would have the least breakage during milling, rice should be sun dried with a thin bed, stirring, shaded or covered around midday and dried on a pad with less air circulation. The optimal drying conditions to get the best quality combined with the fastest practical drying rate, the drying conditions should be drying with 2 cm bed depth, stirring the grain bed every hour, shading or covering the bed around midday and using a tarpaulin or net pad placed directly on the ground.
252

中山先生「民族國家論」之研究 / A Study of Dr. Sun's Theory of Nation-State

金南怡, Kim, Nam I Unknown Date (has links)
本論文之目的,即在採「民族國家建設」、「民族國家整合」的觀點,研究中山先生「民族國家論」的基本意涵,並根據此一理論意涵,探計和比較處理民族國家建設與整合問題的不同策咯以及提出此一理論的特殊之意義與重要功能。   本論文計分六章,僅能論文結構及其內容要點簡述如下:   第一章:諸論   第二章:為了確定中山先生民族國家論的歷史與理論背景,首先歸納出民族主義與民族國家的理論分析。   第三章:民族國家的建設,是時代潮流使然。我們從世界史眼光看來,建設民族國家是現代民族主義所要追求的目標。而致力於提高民族的同質性,乃是建設民族國家的重要策略。在本章中將進一步探計民族國家建設策略與民族國家整合策略。   第四章:中山先生的民族主義積極目的在建設「民族國家」,所以「民族國家論」不僅是其民族主義的理論核心,因此,在本章中將探討中山先生民族國家建設思想的系統分析。   第五章:民族國家整合仍是各國追求的目標,而且經由有效途徑,才有可能在最短的時間內,匯集國內最充足的人力資源,逐漸接近現代化的總目標,但此處所面臨的問題是,甚麼才是解決整合問題約有效途經?吾人在本章中,將特別深計中山先生民族國家整合思想的系統分析。   第六章:詰論。對於本論文之內容做一總結,並提出中山先生「民族國家論」的特殊之意義與重要功能。
253

中國大陸學界對中山先生思想的詮釋與評價之研究(一九七八?一九九三) / Research on The Interpretation and Appraisement of Thoughts of Sun Yet-Sen in Mainland China Schools

李宏文, Lee Hong-Wen Unknown Date (has links)
中山先生思想的歷史哲學是民生史觀,馬克思主義的歷史哲學是唯物史觀,兩者各有其不同的哲學基礎和理論體系,是本質截然不同的思想學說,不宜相混。以馬克思主義立場、觀點和方法研究中山先生思想,其結果將悖離中山先生思想的原貌。將中山先生思想和馬克思主義進行學術上的比較研究,自有其研究價值。但若要正確認識、瞭解中山先生思想,最恰當的方式是根據中山先生思想自身的觀點、體系去進行研究。以馬克思主義的立場、觀點和方法,去從事解釋中山先生思想的作法,那是強將馬克思主義的靈魂注入中山先生思想的軀殼,會造成扞格不入的後果。一些較少遭受馬克思主義束縛的學者的詮釋見解,自然較能反映中山先生思想的本來面貌。 本論文撰寫的主旨,是要探討在馬克思主義意識形態支配下的中國大學界對中山先生思想所作詮釋與評價的諸般情況。 本文共為八章二十五節,全文約四十萬字,各章節重點如下: 第一章:緒論。分為三節,旨在分別闡明本論文的研究動機與研究目的、研究途徑與研究方法,以及資料處理與名詞界定。 第二章:大陸學界詮釋與評價中山先生思想的演變歷程。分為四節,其中包括中共建黨後至建立政權前、中共建立政權後至文革前、文革時期以及文革結束後的改革開放等四個時期,主要在探討中共黨人和大陸學者在這些不同時期詮釋與評價中山先生思想的嬗遞、變遷過程。 第三章:大陸學界詮釋與評價中山先生思想的理架構。分為三節,其中分別對大陸學界據以詮釋、評價中山先生思想的指導架構:馬克思歷史唯物主義,列寧、毛澤東評價中山先生思想的論點,作一觀察與分析。 第四章:大陸學界研究中山先生思想的全局性觀點研析。分為三節,分別就大陸學界如何如「資產階級革命思想」、「三大政策」、「新舊三民主義」等思維模式、制式名辭,以關涉全局式的脈絡融入整個對中山先生思想的詮釋、評價系統,進行研析。 第五章:大陸學界對中山先生民族思想的詮釋與評價。分為三節,主要在探討大陸學界對中山先生的反帝思想與政策、中山先生反滿與大漢族主義間的關係,以及大陸學界對中山先生恢復中國傳統文化和固有道德等思想主張所作的詮釋與評價。 第六章:大陸學界對中山先生權思想的詮釋與評價。分為三節。旨在探討大陸學界對中山先生的革命三程序、權能區分,以及五權憲法等思想主張所作的詮釋與評價。 第七章:大陸學界對中山先生民族思想的詮釋與評價。分為三節,主要在探討大陸學界對中山先生有關資本問題、土地問題,以及發展實業和利用外資等思想主張所作的詮釋與評價。 第八章:結論。分為三節,綜合各章所論,對大陸學界詮釋與評價中山先生思想的全過程作一整體性回顧與提出檢討,並提出對大陸學界詮釋與評價中山先生思想的未來展望和建議,最後一節則在敘明中國統一問題的解決與中山先生建國理念間的重要關聯。
254

Multi Agents for Heterogeneous Operating System Environments

Mathur, Abhishek, n/a January 2007 (has links)
As IT industries develop, upgrade and diversify, heterogeneous operating environments running a mix of new and legacy systems become increasingly important. Such environments are currently inadequate due to lack of compatibility with each other. This thesis investigates how agents can be utilised to facilitate such heterogeneous environments, aiding enterprise systems in building bridges between incompatible software and hardware systems. An autonomous agent has independent agency and decision-making astuteness. When placed in heterogeneous environments to interact with other such agents, the consequences of its action and its preferred choice of actions are greatly influenced by actions of other agents interacting in heterogeneous environments. The main objectives of this thesis include examining the roles of agents in heterogeneous operating environments, development of a novel multi agent base architecture and an associated framework for single and heterogeneous environment. The research work also studies the plausible application to test the developed proof of concept by developing application and using the framework that utilises Windows services in a totally incompatible Solaris based Sun Ray ultra thin client environment. The work includes a novel method of modeling agent based communication architecture suitable for correspondence between two inherently different operating systems - Solaris and Microsoft Windows. The circumstances in which coordination or coordination failure occurs between these systems are investigated. The proposed method of agent based communication that can potentially overcome the barriers formed by two completely different software and hardware architectural regimes. An analysis of printing services in MS Windows and Solaris environments, review the age long problem of lack of device drivers for commonly (and cheaply) available Ink Jet printers for Unix (and like) operating systems. A novel method is proposed that uses agents in heterogeneous environment to overcome this problem. A new architecture that utilises Windows based printing services on a Sun Ray ultra thin client is presented to test and evaluate the proof of concept. This thesis is motivated by the need to provide a low cost printing solution to Sun Ray users. Most Windows based desktop users currently have access to variety of low cost printing solutions. Printer vendors ship device drivers only for Windows or at most Macintosh, as other operating systems such as Solaris, MVS, z/OS are used for corporate solutions and low cost desktop printing have not been a major requirement in the past.
255

Solär Tragedi : Herakleitos Fragm 94

Lindström, Anders January 2009 (has links)
<p>What are the basic thoughts formulated in the Heraclitean fragments? A cosmology, a philosophy of nature, the idea that all can be reduced to a single substance? There is always a risk that Heraclitus is fitted into a thought pattern he doesn’t belong to, if we – from our present horizon – focus on continuity in an attempt to frame his thinking as part of an overall progress, running from the so-called pre-Socratics to Aristotle, in the history of philosophy. If we picture the dawn of Western civilization as an early development of scientific thinking, built on a gradual and continuous growth of knowledge, we will easily go astray as we try to discover the Greek origins of philosophy. Assuming, for example, that the readings of Heraclitus as a natural philosopher have come to a dead end, can we approach the fragments from a different angle?</p><p>The aim of this paper is not to give a systematized reading of all the remaining fragments of Heraclitus, but neither to necessarily contradict the various interpretations that emphasise how these shattered remains reflect a coherent philosophy. The focal point is the role of the sun in the fragments, but every chapter presents different perspectives, thematically possible to connect to (Diels-Kranz) Fragm 94: “The sun will not transgress his measures. If he does, The Furies, ministers of Justice (<em>Dikê</em>), will find him out.” (transl. C.H. Kahn)  This is the centre of the text, the hub that thematically will intertwine the Heraclitean sun with philosophical questions of measure, necessity, law, violence and destiny.</p><p>It is argued that a tragic structure is discernable in Fragm 94, a structure distinguished and displayed as three oscillating layers: myth, tragedy and philosophy. The archaeological approach shows remains of an archaic (Homeric) heritage, a mythological framework crucial for the expression of a tragic experience. The mytopoetical background of the fragment indicates a series of tragic markers – <em>helios</em>, <em>metra</em>, <em>furies</em> etc. – a layer revealing possible resemblances to early Greek tragedy. The third layer shows how this experience, from a philosophical perspective, in the first phase of philosophy, before the consolidation of philosophical concepts, is staged as the tragic harmony we find in Heraclitus Fragm 94.</p>
256

Macromolecular Engineering of Cyclic Aliphatic Polyesters

Li, Haiying 25 January 2007 (has links)
Summary of the thesis This works aims at reporting a novel strategy that combines controlled ring-opening polymerization of lactones initiated by a cyclic tin(IV) dialkoxide and intramolecular cyclization by photo-cross-linking of pendant unsaturations next to the propagating sites. No linear species is ever involved in the polymerization, which allows higher molecular weight macrocycles to be prepared with high efficiency. Moreover, the synthetic route is very flexible to the point where macrocyclic polyesters with more complex although well-defined architectures, such as tadpole-shaped and sun-shaped copolyesters, can be tailored. Synthesis of well-defined star- and eight-shaped polyesters and twin tadpole-shaped amphiphilic copolymers has also been explored by using a spirocyclic tin(IV) alkoxide as initiator.
257

Measuring the solar atmosphere

de la Cruz Rodríguez, Jaime January 2010 (has links)
The new CRISP filter at the Swedish 1-m Solar Telescope provides opportunities for observing the solar atmosphere with unprecedented spatial resolution and cadence. In order to benefit from the high quality of observational data from this instrument, we have developed methods for calibrating and restoring polarized Stokes images, obtained at optical and near infrared wavelengths, taking into account field-of-view variations of the filter properties. In order to facilitate velocity measurements, a time series from a 3D hydrodynamical granulation simulation is used to compute quiet Sun spectral line profiles at different heliocentric angles. The synthetic line profiles, with their convective blueshifts, can be used as absolute references for line-of-sight velocities. Observations of the Ca II 8542 Å line are used to study magnetic fields in chromospheric fibrils. The line wings show the granulation pattern at mid-photospheric heights whereas the overlying chromosphere is seen in the core of the line. Using full Stokes data, we have attempted to observationally verify the alignment of chromospheric fibrils with the magnetic field. Our results suggest that in most cases fibrils are aligned along the magnetic field direction, but we also find examples where this is not the case. Detailed interpretation of Stokes data from spectral lines formed in the chromospheric data can be made using non-LTE inversion codes. For the first time, we use a realistic 3D MHD chromospheric simulation of the quiet Sun to assess how well NLTE inversions recover physical quantities from spectropolarimetric observations of Ca II 8542 Å. We demonstrate that inversions provide realistic estimates of depth-averaged quantities in the chromosphere, although high spectral resolution and high sensitivity are needed to measure quiet Sun chromospheric magnetic fields. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: Manuscript. Paper 3: Submitted. Paper 4: Submitted.
258

Solär Tragedi : Herakleitos Fragm 94

Lindström, Anders January 2009 (has links)
What are the basic thoughts formulated in the Heraclitean fragments? A cosmology, a philosophy of nature, the idea that all can be reduced to a single substance? There is always a risk that Heraclitus is fitted into a thought pattern he doesn’t belong to, if we – from our present horizon – focus on continuity in an attempt to frame his thinking as part of an overall progress, running from the so-called pre-Socratics to Aristotle, in the history of philosophy. If we picture the dawn of Western civilization as an early development of scientific thinking, built on a gradual and continuous growth of knowledge, we will easily go astray as we try to discover the Greek origins of philosophy. Assuming, for example, that the readings of Heraclitus as a natural philosopher have come to a dead end, can we approach the fragments from a different angle? The aim of this paper is not to give a systematized reading of all the remaining fragments of Heraclitus, but neither to necessarily contradict the various interpretations that emphasise how these shattered remains reflect a coherent philosophy. The focal point is the role of the sun in the fragments, but every chapter presents different perspectives, thematically possible to connect to (Diels-Kranz) Fragm 94: “The sun will not transgress his measures. If he does, The Furies, ministers of Justice (Dikê), will find him out.” (transl. C.H. Kahn)  This is the centre of the text, the hub that thematically will intertwine the Heraclitean sun with philosophical questions of measure, necessity, law, violence and destiny. It is argued that a tragic structure is discernable in Fragm 94, a structure distinguished and displayed as three oscillating layers: myth, tragedy and philosophy. The archaeological approach shows remains of an archaic (Homeric) heritage, a mythological framework crucial for the expression of a tragic experience. The mytopoetical background of the fragment indicates a series of tragic markers – helios, metra, furies etc. – a layer revealing possible resemblances to early Greek tragedy. The third layer shows how this experience, from a philosophical perspective, in the first phase of philosophy, before the consolidation of philosophical concepts, is staged as the tragic harmony we find in Heraclitus Fragm 94.
259

Precise nuclear physics for the sun

Bemmerer, Daniel 08 May 2013 (has links) (PDF)
For many centuries, the study of the Sun has been an important testbed for understanding stars that are further away. One of the first astronomical observations Galileo Galilei made in 1612 with the newly invented telescope concerned the sunspots, and in 1814, Joseph von Fraunhofer employed his new spectroscope to discover the absorption lines in the solar spectrum that are now named after him. Even though more refined and new modes of observation are now available than in the days of Galileo and Fraunhofer, the study of the Sun is still high on the agenda of contemporary science, due to three guiding interests. The first is connected to the ages-old human striving to understand the structure of the larger world surrounding us. Modern telescopes, some of them even based outside the Earth’s atmosphere in space, have succeeded in observing astronomical objects that are billions of lightyears away. However, for practical reasons precision data that are important for understanding stars can still only be gained from the Sun. In a sense, the observations of far-away astronomical objects thus call for a more precise study of the closeby, of the Sun, for their interpretation. The second interest stems from the human desire to understand the essence of the world, in particular the elementary particles of which it consists. Large accelerators have been constructed to produce and collide these particles. However, man-made machines can never be as luminous as the Sun when it comes to producing particles. Solar neutrinos have thus served not only as an astronomical tool to understand the Sun’s inner workings, but their behavior on the way from the Sun to the Earth is also being studied with the aim to understand their nature and interactions. The third interest is strictly connected to life on Earth. A multitude of research has shown that even relatively slight changes in the Earth’s climate may strongly affect the living conditions in a number of densely populated areas, mainly near the ocean shore and in arid regions. Thus, great effort is expended on the study of greenhouse gases in the Earth’s atmosphere. Also the Sun, via the solar irradiance and via the effects of the so-called solar wind of magnetic particles on the Earth’s atmosphere, may affect the climate. There is no proof linking solar effects to short-term changes in the Earth’s climate. However, such effects cannot be excluded, either, making it necessary to study the Sun. The experiments summarized in the present work contribute to the present-day study of our Sun by repeating, in the laboratory, some of the nuclear processes that take place in the core of the Sun. They aim to improve the precision of the nuclear cross section data that lay the foundation of the model of the nuclear reactions generating energy and producing neutrinos in the Sun. In order to reach this goal, low-energy nuclear physics experiments are performed. Wherever possible, the data are taken in a low-background, underground environment. There is only one underground accelerator facility in the world, the Laboratory Underground for Nuclear Astrophysics (LUNA) 0.4MV accelerator in the Gran Sasso laboratory in Italy. Much of the research described here is based on experiments at LUNA. Background and feasibility studies shown here lay the base for future, higher-energy underground accelerators. Finally, it is shown that such a device can even be placed in a shallow-underground facility such as the Dresden Felsenkeller without great loss of sensitivity.
260

The Attitude Determination and Control System of the Generic Nanosatellite Bus

Greene, Michael R. 16 February 2010 (has links)
The Generic Nanosatellite Bus (GNB) is a spacecraft platform designed to accommodate the integration of diverse payloads in a common housing of supporting components. The development of the GNB at the Space Flight Laboratory (SFL) under the Canadian Advanced Nanospace eXperiment (CanX) program provides accelerated access to space while reducing non-recurring engineering (NRE) costs. The work presented herein details the development of the attitude determination and control subsystem (ADCS) of the GNB. Specific work on magnetorquer coil assembly, integration, and testing (AIT) and reaction wheel testing is included. The embedded software development and unit-level testing of the GNB sun sensors are discussed. The characterization of the AeroAstro star tracker is also a major focus, with procedures and results presented here. Hardware models were developed and incorporated into SFL's in-house high-fidelity attitude dynamics and control simulation environment. This work focuses on specific contributions to the CanX-3, CanX-4&5, and AISSat-1 nanosatellite missions.

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