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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.
1

Comparative study of Indiana University Foundation and Peking University Education Foundation why they are different and what to learn? /

Xu, Zheng. January 2010 (has links)
Thesis (M.A.)--Indiana University, 2010. / Title from screen (viewed on July 19, 2010). Department of Philanthropic Studies, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Dwight F. Burlingame, William M. Plater, Leslie Lenkowsky. Includes vitae. Includes bibliographical references (leaves 88-95).
2

Comparative Study of Indiana University Foundation and Peking University Education Foundation: Why they are different and what to learn?

Xu, Zheng 19 July 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The thesis made a comparative study of two university foundations, namely Indiana University Foundation, the United States, and Peking University Education Foundation, China, from a historical approach. Many theories influenced the author’s thinking about the issues, such as nonprofit organizations, elite philanthropy, and civil society. The paper seeks to: (1) make an overview of the development of the two foundations; (2) analyze and compare their differences in nature, structure, and fundraising practices, etc.; (3) examine the underlying reasons which may involve social, political, economic and legal factors; and (4) explore the future development of university foundations in China. In an era of accelerated globalization, the boom of diaspora giving and growth of nonprofits set the stage for the development of philanthropy in China. While continuing to draw from the extensive experiences of its American counterparts, the Peking University Education Foundation needs to reflect on its own actual situation and explore a road tailored to Chinese-style university foundations.
3

Enhanced Light Extraction Efficiency from GaN Light Emitting Diodes Using Photonic Crystal Grating Structures

Trieu, Simeon S 01 June 2010 (has links) (PDF)
Gallium nitride (GaN) light emitting diodes (LED) embody a large field of research that aims to replace inefficient, conventional light sources with LEDs that have lower power, higher luminosity, and longer lifetime. This thesis presents an international collaboration effort between the State Key Laboratory for Mesoscopic Physics in Peking University (PKU) of Beijing, China and the Electrical Engineering Department of California Polytechnic State University, San Luis Obispo. Over the course of 2 years, Cal Poly’s side has simulated GaN LEDs within the pure blue wavelength spectrum (460nm), focusing specifically on the effects of reflection gratings, transmission gratings, top and bottom gratings, error gratings, 3-fold symmetric photonic crystal, and 2-fold symmetric nano-imprinted gratings. PKU used our simulation results to fabricate GaN high brightness LEDs from the results of our simulation models. We employed the use of the finite difference time domain (FDTD) method, a computational electromagnetic solution to Maxwell’s equations, to measure light extraction efficiency improvements of the various grating structures. Since the FDTD method was based on the differential form of Maxwell’s equations, it arbitrarily simulated complex grating structures of varying shapes and sizes, as well as the reflection, diffraction, and dispersion of propagating light throughout the device. We presented the optimized case, as well as the optimization trend for each of the single grating structures within a range of simulation parameters on the micron scale and find that single grating structures, on average, doubled the light extraction efficiency of GaN LEDs. Photonic crystal grating research in the micron scale suggested that transmission gratings benefit most when grating cells tightly pack together, while reflection gratings benefit when grating cells space further apart. The total number of grating cells fabricated on a reflection grating layer still affects light extraction efficiency. For the top and bottom grating structures, we performed a partial optimization of the grating sets formed from the optimized single grating cases and found that the direct pairing of optimized single grating structures decreases overall light extraction efficiency. However, through a partial optimization procedure, top and bottom grating designs could improve light extraction efficiency by 118% for that particular case, outperforming either of the single top or bottom grating cases alone. Our research then explored the effects of periodic, positional perturbation in grating designs and found that at a 10-15% randomization factor, light extraction efficiency could improve up to 230% from the original top and bottom grating case. Next, in an experiment with PKU, we mounted a 2-fold symmetric photonic crystal onto a PDMS hemi-cylinder by nano-imprinting to measure the transmission of light at angles from near tangential to normal. Overall transmission of light compared with the non-grating design increases overall light extraction efficiency when integrated over the range of angles. Finally, our research focused on the 3-fold symmetric photonic crystal grating structure and employed the use of 3-D FDTD methods and incoherent light sources to better study the effects of higher-ordered symmetry in grating design. Grating cells were discovered as the source of escaping light from the GaN LED model. The model revealed that light extraction efficiency and the far-field diffraction pattern could be estimated by the position of grating cells in the grating design.
4

北京出張報告

SAWAGUCHI, Yuko, 澤口, 由好 31 March 2012 (has links)
No description available.

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