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台灣與韓國行動電話號碼可攜服務之比較研究 / The Comparative Study of Mobile Number Portability Service between Taiwan and South Korea劉家興, Liu, Chia-Hsin Unknown Date (has links)
近年來國際間電信市場上,由於電信自由化風潮的影響,促進電信市場競爭和保障消費者用戶的相關規定和政策陸續制定出現。號碼可攜服務隨著電信市場的逐漸成熟與開放新進業者的加入等,其實施的迫切性和需求性則越來越重要。另一方面,韓國和台灣兩國皆有相同的共識,先後推動實施所謂的行動電話號碼可攜 (Mobile Number Portability)服務,讓民眾在更換不同行動電話業者服務時,仍能夠保有使用原號碼之權利和便利性。
本論文的研究目的:(一)是想以較台灣先實施行動電話號碼可攜服務的韓國為主要的研究比較個案國家,瞭解韓國電信主管機關的政策制定過程、探討行動通信市場現況、消費者用戶的需求與行動通信業者的回應與市場策略;(二)再輔以參考其他已實施國家經驗中的成功與失敗的因素,與台灣的相關政策、業者策略和消費者用戶的態度等,做綜合性的對照和分析比較,提供台灣在未來實施過程中的建議。
主要的研究方法為文獻分析法與深度訪談法。並且針對「政府相關部門的政策制定」、「消費者用戶的需求」和「行動通信業者之因應策略」,以及「政策實施後所造成的影響」四大問題面向進行探討和分析。
研究分析結果整理發現,韓國和台灣在先後實施行動電話號碼可攜服務之後,的確增加消費者用戶選擇業者的權利,和促進行動通信市場上各家業者的競爭和發展。行動通信業者為了鞏固既有用戶基礎和吸引別家用戶上門,無不提供更多樣的費率包裝和增加服務內容。
研究建議台灣目前已實施之行動電話號碼可攜服務,應該:(一)縮短申請攜碼移轉作業的時程;(二) 加強維護消費者用戶的權益措施;(三) 健全新舊業者之公平競爭機制。 / In recent years, because of the influence from telecommunication liberalization in the international telecommunication market, there are many policies of improving competition in the telecommunication market and protecting consumers are made one after another. Along with that the telecommunication market becomes gradually mature and new operators join competition, the implementation of the number portability service is getting more and more important. On the other hand, South Korea and Taiwan both implemented the so-called "Mobile Number Portability Service", allowing mobile subscribers to switch service operators while retaining the same mobile phone number.
The purpose of this research is: (1) to try to make a comparative study of Mobile Number Portability Service between Taiwan and South Korea. (2) And it will also give some useful suggestions to improve the implementation of Mobile Number Portability Service in Taiwan, by learning experiences from other countries which have implemented Mobile Number Portability Service.
Using literature review method and deep-in interview method, this research discusses and analyzes four major research questions: "the government’s policies", "the subscribers’ demands", "the operators’ strategies" and "the influence from implementing Mobility Number Portability Service".
This research finds out that, after implementation of Mobile Number Portability Service in South Korea and Taiwan, it indeed provides more freedom for subscribers to select service operators and stimulates the competition and development in the telecommunication market. Besides, every service operator provides more tariff packages to consolidate old subscribers and attracts new subscribers form other service operators.
This research suggests the implementation of Mobile Number Portability Service in Taiwan should: (1) reduce the time of application for Mobile Number Portability Service; (2) strengthen the measure of maintaining subscribers’ interests; (3) create a
fair competition mechanism.
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Experimental impact damage resistance and tolerance study of symmetrical and unsymmetrical composite sandwich panelsNash, Peter January 2016 (has links)
This thesis presents the work of an experimental investigation into the impact damage resistance and damage tolerance for symmetrical and unsymmetrical composite honeycomb sandwich panels through in-plane compression. The primary aim of this research is to examine the impact damage resistance of various types of primarily carbon/epoxy skinned sandwich panels with varying skin thickness, skin lay-up, skin material, sandwich asymmetry and core density and investigate the residual in-plane compressive strengths of these panels with a specific focus on how the core of the sandwich contributes to the in-plane compressive behaviour. This aim is supported by four specifically constructed preconditions introduced into panels to provide an additional physical insight into the loading-bearing compression mechanisms. Impact damage was introduced into the panels over a range of IKEs via an instrumented drop-weight impact test rig with a hemi-spherical nosed impactor. The damage resistance in terms of the onset and propagation of various dominant damage mechanisms was characterised using damage extent in both impacted skin and core, absorbed energy and dent depth. Primary damage mechanisms were found to be impacted skin delamination and core crushing, regardless of skin and core combinations and at high energies, the impacted skin was fractured. In rare cases, interfacial skin/core debonding was found to occur. Significant increases in damage resistance were observed when skin thickness and core density were increased. The reduction trends of the residual in-plane compressive strengths of all the panels were evaluated using IKE, delamination and crushed core extents and dent depth. The majority of impact damaged panels were found to fail in the mid-section and suffered an initial decline in their residual compressive strengths. Thicker skinned and higher density core panels maintained their residual strength over a larger impact energy range. Final CAI strength reductions were observed in all panels when fibre fracture in the impacted skin was present after impact. Thinner skinned panels had a greater compressive strength over the thicker skinned panels, and panel asymmetry in thin symmetrical panels appeared to result in an improving damage tolerance trend as IKE was increased due to that the impact damage balanced the in-plane compressive resistance in the skins with respect to the pre-existing neutral plane shift due to the uneven skin thickness.
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A synergy between well-defined homogeneous and heterogeneous catalysts : the case of Ring Opening - Ring Closing Metathesis of cyclooctene / Une synergie entre des catalyseurs hétérogènes ou homogènes bien définis : application à la réaction tandem d’ouverture et de fermeture de cycle par métathèse (RO-RCM) du cyclo-octèneKavitake, Santosh 14 October 2011 (has links)
Dans le cadre de la formation sélective d'oligomères cycliques à partir du cyclo-octène, des matériaux hybrides organiques-inorganiques mésostructurés bien-définis contenant les unités Ru-NHC dissymétriques le long des canaux poreux de leur matrice de silice ont été développés et caractérisés à un niveau moléculaire. Tous les systèmes obtenus ont montré des fortes activités et sélectivités en oligomères cycliques (dimères : 50% et trimères : 25%) en RO-RCM du cyclo-octène, contrairement aux complexes homogènes Ru-NHC analogues symétriques (G-II et GH-II), qui conduisent préférentiellement à la formation de polymères. La variation de la longueur et de la flexibilité des bras espaceurs, dans le cas des catalyseurs hétérogènes, a prouvé que les bras courts et flexibles stabilisent grandement les sites actifs Ru-NHC pendant la réaction de métathèse et ce, grâce à la présence d'interactions entre les sites Ru-NHC catalytiquement actifs et la surface silicique. La présence de telles interactions a été mise en évidence par RMN du phosphore 31 à l'état solide. Des études supplémentaires concernant les performances catalytiques de complexes organométalliques Ru-NHC dissymétriques (analogues aux sites Ru-NHC contenus dans les catalyseurs hétérogènes) et Ru-NHC symétriques (G-II et Nolan) ont clairement montré que le facteur clé influençant la sélectivité en oligomères cycliques est la dissymétrie des ligands NHC. Cette dissymétrie génère la présence de deux sites actifs de configurations différentes au sein même des espèces Ru-NHC. Un des sites favorise la réaction intramoléculaire de fermeture de cycle par métathèse alors que l'autre site permet la réaction intermoléculaire d'ouverture de cycle conduisant ainsi à la formation des oligomères cycliques de petite taille / In the context of the selective formation of cyclic oligomers from cyclooctene, well-defined hybrid organic-inorganic mesoporous materials containing unsymmetrical Ru-NHC units along the pore channel of their silica matrix have been developed and characterized at a molecular level. All systems displayed high activity and selectivity towards the formation of lower cyclic oligomers in the RO-RCM of cyclooctene yielding mainly the dimer and the trimer with 50% and 25% selectivity, respectively, in contrast to classical symmetrical homogeneous analogues (G-II and GH-II), which yield mainly to polymers. Variation of length and flexibility of the tethers showed that flexible short tethers were critical for high stability of the catalysts during metathesis, which is consistent with the stabilization of Ru-NHC active sites by surface functionalities; this surface interaction was further corroborated by the absence of a PCy3 ligand coordinated to Ru when short flexible linkers are used. Further investigations using homogeneous symmetrical (G-II and Nolan) and unsymmetrical (analogues to heterogeneous catalysts) Ru-NHC catalysts clearly showed that the key factor influencing the selectivity towards low cyclic oligomers is the unsymmetrical nature of NHC ligands, which creates dual site configuration in the catalyst architecture thus alternatively favouring one reaction over another, Ring Opening (ROM) vs. Ring Closing (RCM) Metathesis (propagation vs. backbiting), thus leading to the selective tandem RO RCM of cyclooctene. Finally, we have also investigated Grubbs Hoveyda-II (GH-II) type catalysts immobilized on silica support through adsorption, which showed the same product selectivity as that of the well-defined Ru-NHC materials. This result implies that the adsorbed symmetrical GH-II catalyst “becomes unsymmetrical upon adsorption”. Adsorbing unsymmetrical molecular GH II catalysts did not however improve the performances of these types of catalysts. Overall, the unique property of unsymmetrical NHC Ru catalyst, whether supported or not, opens new perspectives in the selective synthesis of macrocycles from other cyclic alkenes via metathesis
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Synthesis of Fluorescent Molecules and their Applications as Viscosity Sensors, Metal Ion Indicators, and Near-Infrared ProbesWang, Mengyuan 01 January 2014 (has links)
The primary focus of this dissertation is the development of novel fluorescent near-infrared molecules for various applications. In Chapter 1, a compound dU-BZ synthesized via Sonogashira coupling reaction methodology is described. A deoxyuridine building block was introduced to enhance hydrophilic properties and reduce toxicity, while an alkynylated benzothiazolium dye was incorporated for near-IR emission and reduce photodamage and phototoxicity that is characteristic of common fluorphores that are excited by UV or visible light. A 30-fold enhancement of fluorescence intensity of dU-BZ was achieved in a viscous environment. Values of fluorescence quantum yields in 99% glycerol/1% methanol (v/v) of varying temperature from 293 K to 343 K, together with fluorescence quantum yields, radiative and nonradiative rate constants and fluorescence lifetimes in glycerol/methanol solutions of varying viscosities from 4.8 to 950 cP were determined. It was found that both fluorescence quantum yields and fluorescence lifetimes increased with increasing viscosity, which is consistent with results predicted by theory. This suggests that the newly designed compound dU-BZ is capable of functioning as a probe of local microviscosity, and was later confirmed by in vitro bioimaging experiments. In Chapter 2, a new BAPTA (O,O*-bis(2-aminophenyl)ethyleneglycol-N,N,N*,N*-tetra acetic acid) and BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene)-based calcium indicator, BAPBO-3, is reported. A new synthetic route was employed to simplify both synthesis and purification, which tend to be low yielding and cumbersome for BAPTA derivatives. Upon excitation, a 1.5-fold increase in fluorescence intensity in buffer containing 39 ?? Ca2+ and a 3-fold increase in fluorescence intensity in buffer containing 1 M Ca2+ was observed; modest but promising fluorescence turn-on enhancements. In Chapter 3, a newly-designed unsymmetrical squaraine dye, SQ3, was synthesized. A one-pot synthesis was employed resulting in a 10% yield, a result that is generally quite favorable for the creation of unsymmetrical squaraines Photophysical and photochemical characterization was conducted in various solvents, and a 678 nm absorption maximum and a 692 nm emission maximum were recorded in DMSO solution with a fluorescence quantum yield of 0.32. In vitro cell studies demonstrated that SQ3 can be used as a near-IR probe for bioimaging.
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Dioxygen reactivity of new models of copper oxygenases : electrochemical and spectroscopic studies / Réactivité vis-à-vis de l’oxygène des nouveaux modèles dinucléaires au cuivre : études électrochimiques et spectroscopiquesGennarini, Federica 29 November 2017 (has links)
La molécule de méthane possède la liaison C-H la plus forte parmi les hydrocarbures (BDE = 104 kcal mol-1) : son oxydation en conditions douces représente un challenge d'importance. La Méthane Monoxygénase particulaire (pMMO) est une enzyme à cuivre qui catalyse l'oxydation du méthane (CH4) en méthanol (CH3OH). Le site actif de l'enzyme est composé d'atomes de cuivre séparés par 2.6 Å. Des recherches récentes suggèrent qu'un cluster Cu2 III,II/O2 à valence mixte soit un intermédiaire-clé du cycle catalytique. L'objectif de ce travail vise à la synthèse et caractérisation de nouveaux complexes dinucléaires à valence mixte de type bis(µ-oxo)Cu2 III,II ou (µ-OH, µ-O)Cu2 III,II. Deux familles de motifs coordinants ont été mises en oeuvre, polypyridyle ou polyamide ; les deux sites sont assemblés par des ponts courts et rigides, phenoxo, naphthyridine ou alkoxo. De nouveaux complexes ont été caractérisés par électrochimie, spectroscopies UV-visible et RPE, et par des calculs théoriques. Un dispositif original de cryo-spectroélectrochimie UV-vis-NIR a été développé en parallèle de cette étude : il permet l'identification spectroscopique d'intermédiaires transitoires, réputés très instables à température ambiante. De nouveaux composés à valence mixte, Cu2 III,II(μ-OH, μ-O) et Cu2 III,IIbis(μ-OH) ont été identifiés. Ces résultats élargissent le champ des données de cette famille d'intermédiaires instables limitée jusqu'ici à un seul exemple. / Methane has the strongest C-H bond of any hydrocarbon (BDE = 104 kcal mol-1); its oxidation under mild conditions remains a great challenge. The particulate Methane Monooxygenase (pMMO) is a copper enzyme that oxides methane (CH4) to methanol (CH3OH). In the active site of the enzyme, two copper ions are located at a short distance (2.6 Å). Recent researches have suggested a mixed-valent Cu2III,II/O2 cluster as a key intermediate in the catalytic cycle. The main objective of this work was the synthesis and characterization of new mixed-valent CuIIICuII bis(μ-oxo) and (μ-OH, μ-O) dinuclear complexes. For this purpose we designed promising symmetrical and unsymmetrical complexes based on specific and distinct scaffolds for each side of the structure. Two families of coordination pattern have been used, polypyridyle or polyamide; the two sites are shortly and rigidly bridged by phenoxo, alkoxo or naphthyridine linkers. New complexes have been characterized by electrochemistry, UV-vis and EPR spectroscopies, and by theoretical calculations. A new cryo-UV-Vis-NIR spectroelectrochemical set up, developed in parallel during this work, has allowed the spectroscopic identification of these transient intermediate species, known to be unstable at room temperature. New mixed-valence Cu2 III,II(μ-OH, μ-O) and Cu2 III,IIbis(μ-OH) complexes have been characterized. These results expand the recent knowledge on the only mixed valent CuIII(μ-OH)CuII species described so far.
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Testování lokátoru poruch na nesymetrickém vedení / Earth fault locator testing on the model of unsymmetrical linesKohůt, Miroslav January 2016 (has links)
This master’s thesis is about earth fault locator testing on the model of unsymmetrical lines. The introductory part of thesis describes the function of the selected locator, mainly for the used calculation algorithm of fault location, options setting of fault locator and connection of the locator to the network. Master’s thesis in its practical part deals, with the setting fault locator for a particular test system on the model of the MV line and implementation of selected testing on the model unsymmetrical lines. The first part of the testing is focusing on verify the accuracy locator on an unsymmetrical line. The second test is then designed for obtaining the most accurate information on the distance of the fault, which fault locator can give. The final part is focused on verification algorithm for more accurate calculation of the fault location.
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Modelling, Analysis, and Control Aspects of a Rotating Power Electronic Brushless Doubly-Fed Induction GeneratorMalik, Naveed ur Rehman January 2015 (has links)
This thesis deals with the modeling, analysis and control of a novel brushlessgenerator for wind power application. The generator is named as rotatingpower electronic brushless doubly-fed induction machine/generator (RPEBDFIM/G). A great advantage of the RPE-BDFIG is that the slip power recoveryis realized in a brushless manner. This is achieved by introducing an additionalmachine termed as exciter together with the rotating power electronicconverters, which are mounted on the shaft of a DFIG. It is shown that theexciter recovers the slip power in a mechanical manner, and delivers it backto the grid. As a result, slip rings and carbon brushes can be eliminated,increasing the robustness of the system, and reducing the maintenance costsand down-time of the turbine. To begin with, the dynamic model of the RPE-BDFIG is developed andanalyzed. Using the dynamic model, the working principle of the generatoris understood and its operation explained. The analysis is carried out atspeeds, ±20% around the synchronous speed of the generator. Moreover, thedynamics of the generator due to external load-torque disturbances are investigated.Additionally, the steady-state model is also derived and analyzed forthe machine, when operating in motor mode. As a next step, the closed-loop control of the generator is considered indetail. The power and speed control of the two machines of the generator andthe dc-link voltage control is designed using internal model control (IMC)principles. It is found that it is possible to maintain the stability of thegenerator against load-torque disturbances from the turbine and the exciter,at the same time maintain a constant dc-link voltage of the rotor converter.The closed-loop control is also implemented and the operation of the generatorwith the control theory is confirmed through experiments.In the third part of the thesis, the impact of grid faults on the behaviourof the generator is investigated. The operation of the generator and its responseis studied during symmetrical and unsymmetrical faults. An approachto successful ride through of the symmetrical faults is presented, using passiveresistive network (PRN). Moreover, in order to limit the electrical and mechanicaloscillations in the generator during unsymmetrical faults, the dualvector control (DVC) is implemented. It is found that DVC to a certain extentcan be used to safeguard the converter against large oscillations in rotorcurrents. Finally, for completeness of the thesis, a preliminary physical design ofthe rotating power electronic converter has been done in a finite elementsoftware called ANSYS. The thermal footprint and the cooling capability,with estimates of the heatsink and fan sizes, are presented. Besides, another variant of a rotating electronic induction machine whichis based on the Lindmark concept and operating in a single-fed mode is also investigated. It’s steady-state model is developed and verified through experiments. / <p>QC 20151006</p>
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Analysis and Control Aspects of Brushless Induction Machines with Rotating Power Electronic ConvertersMalik, Naveed ur Rehman January 2012 (has links)
This thesis deals with the steady-state, dynamic and control aspects of new type of brushless configuration of a doubly-fed induction machine in which the slip rings and carbon brushes are replaced by rotating power electronics and a rotating exciter. The aim is to study the stability of this novel configuration of the generator under mechanical and grid disturbances for wind power applications. The derivation, development and analysis of the steady-state model of the brushless doubly-fed induction machine with a rotating excitor and the power electronic converters mounted on the shaft and rotating with it, is studied. The study is performed at rated power of the generator between ±20% slip range. Moreover unity power factor operation between ±20% speed range is also discussed. Furthermore dynamic modeling and control aspects of the generator are also analyzed. The controllers were designed using Internal Model Control principles and vector control methods were used in order to control the generator in a closed-loop system. It is shown that through the use of proper feedback control, the generator behaves in a stable state both at super-synchronous and sub-synchronous speeds. Moreover Low Voltage Ride Through of the generator during symmetrical and unsymmetrical voltage dips is also investigated. Passive Resistive Network strategy is employed for Low Voltage Ride Through of the generator during symmetrical voltage dips. On the other hand, Extended Vector Control is used in order to control the negative sequence currents during unsymmetrical voltage dips. Suppression of negative sequence currents is important as they cause extra heating in the windings and affects the lifetime of the mechanical and electrical components of the generator and system due to oscillations in power and torque. In addition to the above studies a steady-state model of a single-fed induction machine is also developed and investigated where the rotating exciter is removed and the rotor windings are short-circuited through the two rotating power electronic converters. In this way the slip power circulates in the rotor and with the help of the two rotating electronic converters, rotor current is used to magnetize the induction machine thereby improving the power factor. The steady state model is verified through experimental results. / <p>20120914</p> / Brushless Wind Generator with Rotating Power Electronic Converters
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