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991.
992.
Choi Kyunghee Yun Sungjae Jung Gihyun Naeheon Kim 《Electronics letters》1997,33(15):1301-1302
An optimal scheduling algorithm for imprecise systems is presented. The proposed algorithm aims at minimising the maximum weighted errors. A novel property of the algorithm is that the errors are evenly distributed among scheduled tasks. The complexity of the proposed algorithm is O(N3) in the worst case, where N is the number of tasks 相似文献
993.
Galtarossa A. Yongmin Jung Kim M.J. Lee B.H. Kyunghwan Oh Un-Chul Paek Palmieri L. Pizzinat A. Schenato L. 《Lightwave Technology, Journal of》2005,23(12):4184-4191
Spinning a fiber is the most viable and used technique to reduce polarization mode dispersion (PMD). Many papers have shown that by properly tuning the spin parameters, the differential group delay (DGD) of spun fibers can be greatly reduced. However, the precision with which these optimal profiles are practically implemented may be a problem. In this paper, we perform a statistical analysis of the effects that spin inaccuracy may have on fiber PMD, quantifying how the random uncertainty on spin parameters impairs the DGD. Some preliminary experimental results about spin-induced PMD reduction are also reported. 相似文献
994.
While extensive research on the lead-free solder has been conducted, the high melting temperature of the lead-free solder
has detrimental effects on the packages. Thermosonic bonding between metal bumps and lead-free solder using the longitudinal
ultrasonic is investigated through numerical analysis and experiments for low-temperature soldering. The results of numerical
calculation and measured viscoelastic properties show that a substantial amount of heat is generated in the solder bump due
to viscoelastic heating. When the Au bump is thermosonically bonded to the lead-free solder bump (Sn-3%Ag-0.5%Cu), the entire
Au bump is dissolved rapidly into the solder within 1 sec, which is caused by the scrubbing action of the ultrasonic. More
reliable solder joints are obtained using the Cu/Ni/Au bump, which can be applied to flip-chip bonding. 相似文献
995.
K. H. Jung M.S. T. Y. Hsieh M.A. D. L. Kwong Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1991,43(10):38-43
The future of ultralarge-scale integration technology is tending toward reduced thermal processing to realize devices with higher integration densities and better performance. Rapid thermal processing chemical vapor deposition (RTPCVD) is a promising technology that can preserve the advantages of high-temperature processing without degrading the fidelity of junction profiles. Defect free, thin silicon epilayers with extremely abrupt dopant-transition profiles can be re-producibly grown by RTPCVD. Very high quality n-type and p-type heavily doped epilayers, using boron, arsenic, and phosphorus as dopants, have been grown by RTPCVD. Through superior process control and reduced thermal exposure, RTPCVD is expected to play an important part in the next generation of fabrication technology and in the development of novel silicon-based materials. 相似文献
996.
997.
Yeonsub Jung PoongHyun Seong ManCheol Kim 《Reliability Engineering & System Safety》2004,83(3):351-362
A model for plant operating procedure based on flowchart and success logic tree has been developed. The tasks in procedures are classified into orthogonal actions and checks, which play the role of building units of the flowchart as well as an execution unit of procedures. Arrows relate actions and checks to indicate proper workflow. An action or a check is further decomposed into basic instructions considering function allocation between man and computer, characteristics of tasks, etc. N-out-of-M operator combines the instructions within a success logic tree. The flowchart and the tree are comprehensible, transparent, and dynamic. Computers support operators to execute the instructions. The effort to make the tree in allowable states is the driving force for an action or check to be executed successfully. This model improves understandings of procedures, minimizes context switching, and maximizes the usage of computers. Finally a computer based procedure complying with the model was implemented and evaluated with procedures after reactor trip. 相似文献
998.
999.
R Fries A Heisel N Nikoloudakis J Jung HJ Sch?fers H Schieffer 《Canadian Metallurgical Quarterly》1997,80(11):1487-1489
We analyzed spontaneous ventricular tachycardias treated by antitachycardia pacing during long-term follow-up in 138 recipients of an implantable cardioverter-defibrillator. An inverse circadian variation of the antitachycardia pacing termination and acceleration rates with the worst antitachycardia pacing success during the time period with the highest episode frequency (morning hours) was demonstrated. 相似文献
1000.
Kyu-Hyoun Kim Kwyro Lee Tae-Sung Jung Kang-Deog Suh 《Solid-State Circuits, IEEE Journal of》1998,33(11):1758-1762
This paper describes a fast and accurate nonvolatile analog memory (NVAM) and its programming scheme. Both constant programming rate and single-pulse programmability have been achieved, which drastically enhance programming speed and accuracy. A prototype chip containing 8×128 NVAM cells (cell size of 9×13.6 μm2) has been fabricated using 0.8-μm CMOS. Each cell is measured to store more than eight bit levels within 360 μs 相似文献