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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.

The Study of Microstructure and Joint Strength for Fluxless AuSn Solders in Laser Diode Package

Ho, Yi-hsing 12 July 2004 (has links)
The joint strength and microsturcture for fluxless AuSn solders in packaging of InP substrate onto Si submount after thermal-aging testing were studied experimentally. Specimens were aged at 150¢XC for up to 64days. The joint strength decreased as aging time increased. Under the 64days aging,the bonding strength of AuSn solders decreased from 195g to 125g. This matches to the ¡§MIL-STD-METHOD 2019.7¡¨ which is the minimum bonding strength of 93g. The microstructure of the AuSn solders joint showed the joint strength decrease was caused by the enlargement of the initial voids and an increase in the thickness of intermetallic compound(IMC). The effect of temperature cycle testing on the power variation of 1550nm laser chips using fluxless AuSn solders in laser diode packages was also studied. The temperature cycle testing was from -20¢XC to +100¢XC within a cycle of 110 minutes. It was shown that the 1550nm laser diodes operated in the stable condition up to 300 cylces.

Economics of tour packaging

Sheldon, Pauline J January 1984 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1984. / Bibliography: leaves 182-185. / Microfiche. / lMaster negative: Microfiche MS33168. / ix, 185 leaves, bound ill. 29 cm

The Study of the Moisture Effect on the Interfacial adhesion of IC Packages in the IR-Reflow Process

Weng, Da-Jiun 16 July 2002 (has links)
Abstract¡G This study imitated the IC package with different solder mask thickness in different environment of the temperature and moisture to see if the adhesion strength changed after IR-Reflow process. The temperature and moisture of the environment were decided base on the possible conditions that the IC package might encounter in the real situation. After the temperature and moisture in the environment worked interactively and reciprocally, we found that the thickness of solder mask indeed cause the change of adhesion strength. The thickness of solder mask affected by the raising of the temperature and moisture caused the apparent reduction of the interface adhesion strength due to the softening of the material and the penetrating of the moisture. Besides, the specimen fracture surface occurred between solder mask and FR-4 substrate under any experimental conditions and progress confirmed that the measured strength is the adhesion strength between solder mask and FR-4.

A Study Of Technology Transfer Mechanism For IC Packing Process

Lin, Cheng-Nan 19 August 2004 (has links)
The current packaging trend toward smaller and thinner package has pushed the manufacturing technology to the limit. Due to fast development of encapsulation technology, the need for shortening factory time and upgrading technological ability are vital to promote companys¡¦ competitiveness. Most of IC packing factory are expanding resources to adapt on the technology development needs. Technology transfer methods are utilized to effectively cope with the technology trend. This research takes technology suppliers, characters of the technology and receivers of technology as three major independent variables. In other words, the negative effect of the absorptive capacity can be reduced effectively by using proper technology transfer mechanism and thus achieving satisfactory performance. In the technology transfer process , in-depth factors other than existing procedures and rules are considered. This will affect the effectiveness and goals of the transfer. Besides, the technology characteristics and technology transfer performance are related to each other. The knowledge and ability to technology transfer with shorter gap between technology provider and accepter, help developing new products and improving management process with consolidated firm competitiveness and has become the significant theme of the 21st century. Keyword: Technology transfer¡BIC Package

A systematic review on impact of plain cigarette packaging

Yim, Cheuk-yee, Wendy, 嚴綽怡 January 2013 (has links)
WHO recommends the use of plain packaging to combat marketing abuse of cigarette packaging. The present systematic review aims to review and synthesize existing significant findings for effect of plain cigarette packaging, discuss implications for Hong Kong cigarette packaging policy, and offer suggestions for future direction in the area of research studies. A total of 21 studies were selected and qualified through the PRISMA Statement. Results were synthesized according to primary and secondary findings. Significant findings indicate that plain cigarette packages lower the attractiveness of a pack, weaken the reinforcement of falsely perceived product strength and arm, while increase the effectiveness of health warnings. The relatively new topic gives the present review its strengths and limitations. The review recommends Hong Kong to conduct local research in the area to support governmental decision in the implementation. / published_or_final_version / Public Health / Master / Master of Public Health

Real-time three dimensional coordinate measurement and analysis : system design, implementation and testing

El-Gohary, Ahmed M. January 1989 (has links)
No description available.

The Study of Light Extraction Efficiency for High Power LED Package

Chen, Chien-chung 06 July 2006 (has links)
In this thesis, we focus on the light extraction efficiency of LED package. The light extraction efficiency of LED is limited by Fresnel Loss and total internal reflection, which result in the rare amount of luminious flux from LED. In order to improve the light extraction efficiency of high power LED package, we study the design of package structure and the matching refractive index of silicone resins. Instead of using one-layer structure, we use multi-layer structure which can raise the light extraction efficiency and the brightness. In order to destroy the total internal reflection, we change the geometric appearance and the interior structure and furthermore we use the different refractive index of silicone resins to decrease Fresnel Loss. In this work, we use the multi-layer structure whose the refractive indexes of the inner silicone resin and the outer silicone resin are 1.55 and 1.41 respectively. When the geometric appearance is convex, the light extraction efficiency of LED package can reach to 70%. Furthermore, by applying this result on phosphor conversion light emitting diode, we can get high efficiency of white light.

The Study of High Power White Phosphor-Conversion LED Package

Chen, Chiao-wen 15 July 2006 (has links)
Light emitting diodes (LEDs) are generally used in daily life. Our major target is to increase the brightness of LED. We study the package of white phosphor-conversion light emitting diodes (PC-LEDs) and analyze the effect on the luminous flux and color temperature from different locations and concentrations of phosphor coatings and deposition of phosphor. In this study, the color temperature and luminous flux are measured. When the phosphor is placed on the top of the reflected cup with 1.5% of concentration, or on the bottom with 7% of concentration, or when it fills the reflected cup with 1.5% of concentration, the luminous flux is about 40 lm under the CIE 1931 color coordinate of (0.33,0.33). We also studied the effect on deposition of phosphor of two different viscosities of resin used to package white PC-LED. The luminous flux which is packaged with higher viscosity resin is about 12% higher than the one found with the lower viscosity resin. After two hours of deposition, the luminous flux of the white PC-LED which is packaged with the resin of lower viscosity increased 4%, and the one packaged with the resin of higher viscosity increased 7%.

A postmodern poetics of the group package tour /

Leung, Sai-chung, Arthur. January 2002 (has links)
Thesis (M.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 55-57).

An analysis of Caribbean travel products and services used in tour packages developed by U.S. tour operators

Chansawang, Jeed Rochaporn. January 1999 (has links) (PDF)
Thesis--PlanA (M.S.)--University of Wisconsin--Stout, 1999. / Includes bibliographical references.

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