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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.
151

Discussion of Charge Transfer Mechanism and Proteins Detection by Surface-Assisted Laser Desorption Ionization Method with Application of CdTe Quantum Dots

Chen, Zhen-yu 10 August 2010 (has links)
none
152

Investigation on Operating Characteristics of Individual Cell among Battery Pack

Chen, Wen-Chih 04 July 2006 (has links)
Due to the discrepancy among series-connected cells in a lead-acid battery pack, the restored capacities may not be the same during the charging/discharging processes. Through repeated charging and discharging, one can find that the unbalance of individual series-connected battery cell of lead-acid battery is getting worse, because those cells of poor state of charge may have negative voltage, causing reverse charging from the other cells. This abnormal operation results in not only more energy consumption, but also the acceleration of the battery-cell aging and the remarkable reduction of its lifetime. For the purpose of investigating this problem, the operating characteristics of each cell is under study. The battery cells are purposely charged by different floating voltages and discharged by different cutoff voltages. The investigation results show that the lifecycles of battery cells are affected more significantly by floating charging voltage than by the discharging cutoff voltage. It is also found that a long time reverse charging has a destructive effect on the battery cells.
153

Investigation into the Current Rezoning System and Related Concerns with Regard to Land Utilization in Taiwan Area

Huang, Chien-Lung 30 August 2001 (has links)
From the viewpoint of land economics, any change in land use manner will require new public facilities added to the area under development and bear external impact on the area. The merit of the fundamental principle to remove, through levying rezoning on land use, the external effects brought on by alterations in development should be recognized. However, because the levy of rezoning on land utilization involves people¡¦s rights and obligations, the proper execution of this system has a considerable impact on people¡¦s privilege. The current rezoning system on land utilization implemented in Taiwan has been in practice for many years; it is also widely criticized. Concerns over such subjects as ambiguous definition and nature of rezoning, lack of legal status for the levy of rezoning, lack of standard for the calculation of rezoning amounts are usually raised. Therefore, the government must work to try to establish a complete, reasonable rezoning system on land utilization. The author conducted the research by examining the system of impact fees and linkage fees implemented in the United States, the planning obligations system implemented in Britain, and the development charge system implemented in Singapore and examining their experience, and reviewing the relevant laws and concerns with regard to the current rezoning on land utilization in Taiwan. Moreover, after analyzing and describing the policy trend of the government¡¦s effort to establish the land development obligations system, the author tried to understand, through case study, questionnaire inquiry and interview methods, the opinion of scholars and experts, land and estate developers, government offices, and local residents, and then based on this understanding, tried to formulate a framework that would be appropriate for the rezoning system on land utilization in Taiwan. The study maintains that in implementing the rezoning system on land utilization, the most important principle is to respect the market function and endow the levy of rezoning with legal status. Then in conformity with this principle, complete and reasonable measures concerning the rezoning system on land utilization are to be constructed. This study suggests that, in a short period of time, the statute that governs the levy of rezoning, to name one ¡V Urban Planning law, be revised so that the rezoning system can gain legal ground and be implemented legally. At the same time, the negotiating mechanism for development permit should be strengthened so that the external cost influenced by development can be effectively included as the content for negotiation. For the long term, the central authority in charge should integrate the separate regulations on rezoning that belong to various offices in charge so as to establish a reasonable rezoning system on land utilization that conforms to the market function and to give this system a legal status. This status should be the basis for the implementation of this system. The applicant for alterations in land utilization should be the subject for the levy, and the levy should be executed in the form of cash donation, land donation and construction of public facilities. The government administration should be considered. For the levy amounts, calculation equations can be established as part of this system, and the concerned local government and the owner should negotiate to figure out the upper and lower limits of the estimated amount. The time to levy should be decided separately from the levy method, but they should match. With regard to the use, management and maintenance of rezoning items, the concerned local government should, according to the characteristics of rezoning items, establish accounts and authorities for special funds. These special funds should be only appropriated for improving, constructing, and managing the public facilities that have been influenced by alterations in land utilization. This perfect rezoning system on land utilization should enable the government, developer, and local residents to share land resources and harvest the plentiful fruit of perennial development.
154

Analysis of the Charge Transport Mechanisms in Bilayer Organic Light-Emitting Diode

Chu, Chiu-Ping 27 June 2002 (has links)
The charge-carriers of the organic layers are one of the dominant factors to influence the performance of OLEDs. Thus, it is very important to study and understand the charge transporting behaviors in the organic layers of OLED. However, the organic materials show usually to have very high resistivity and very low carrier mobility, and then using general modeling techniques suitable for common semiconductors cannot conveniently simulate that. First, a transporting model of the bilayer organic OLED are proposed in this dissertation, in which model were based on the current-voltage characteristics simulation proposed by Lampert and the continuous equation of current transport. The model contains a description of ohmic contacts, thermal emission and tunneling injection, space charge effects, trap effect, field dependent mobility and recombination processes. In addition, the method of Monte Carlo is a computational technique by using random numbers to compute an approximation to something whose exact value is difficult or impossible to compute, and that is used to simulate the bilayer organic OLED. In this study, a numerical model proposed is successfully applied to describe the characteristics of the bilayer organic light-emitting diode. The model is satisfyingly demonstrated not only for applying to simulate several bilayer devices (1-Naphdata/Alq3¡BTPD/Alq3) reported but also for some devices obtained in our results. Finally, it can be extended to optimize the analysis and fabrication of bilayer devices.
155

Relations Between Resonance Raman Spectra and The Second Order Optical Nonlinearity of Charge Transfer Chromophores

Hung, Sheng-Ting 10 July 2003 (has links)
The linear absorption spectrum and resonance Raman spectrum of a series of charge-transfer molecules in solution are measured. The results are fitted to theoretical expressions. The dispersion of the first hyper-polarizability is investigated by substituting the parameters, which are obtained from the fit. The results are compared with Wang's formula modified from the simple Oudar and Chemla two-level model. The resonance Raman spectra and Raman profiles show that only one excited state exists in two of the charge-transfer molecules and two excited states are present in three other molecules investigated in this expeariment. It is concluded that Wang's modified formula is only valid to account for the dispersion of the first hyperpolarizability when there is only one excited vibronic state.
156

Spectroscopic investigation of the excited state properties of platinum (II) charge transfer chromophores

Glik, Elena A. January 2009 (has links)
Thesis (Ph.D.)--Bowling Green State University, 2009. / Document formatted into pages; contains xv, 200 p. : ill. Includes bibliographical references.
157

Corrélations entre les propriétés diélectriques et mécaniques des polymères Influence de la température /

Dutriez, Cédric. Treheux, Daniel. January 2004 (has links) (PDF)
Thèse de doctorat : sciences. Génie des matériaux : Ecully, Ecole centrale de Lyon : 2004. / 98 réf.
158

Corrélations entre les propriétés diélectriques et mécaniques des polymères Influence de la température /

Dutriez, Cédric. Treheux, Daniel. January 2004 (has links) (PDF)
Thèse de doctorat : sciences. Génie des matériaux : Ecully, Ecole centrale de Lyon : 2004. / Titre provenant de l'écran-titre. 98 réf.
159

Caractéristique de la charge électrique d'un aérosol radioactif naturel

Abou-Khalil, Roger Nourreddine, Abdelmjid January 2009 (has links) (PDF)
Thèse de doctorat : Physique et instrumentation nucléaire : Strasbourg 1 : 2008. / Titre provenant de l'écran-titre. Bibliogr. p. 126-130.
160

Échanges de charge et perte d'énergie d'ions lourds ralentis, canalisés dans des cristaux de silicium

Testa, Étienne Chevallier, Michel. January 2005 (has links) (PDF)
Reproduction de : Thèse de doctorat : Physique des particules : Lyon 1 : 2005. / Titre provenant de l'écran titre. 92 réf. bibliographiques.

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