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22.
从PCI/ISA到双总线ePCI-X, 一种设计重用方法   在当今的PCI/ISA背板中,显然PC芯片组ISA插槽的数量在减少,PCI插槽的数量在增多.……  相似文献   
23.
We give generic constructions of several fundamental cryptographic primitives based on a new encryption primitive that combines circular security for bit encryption with the so-called reproducibility property (Bellare et al. in Public key cryptography—PKC 2003, vol. 2567, pp. 85–99, Springer, 2003). At the heart of our constructions is a novel technique which gives a way of de-randomizing reproducible public-key bit encryption schemes and also a way of reducing one-wayness conditions of a constructed trapdoor function family (TDF) to circular security of the base scheme. The main primitives that we build from our encryption primitive include k-wise one-way TDFs (Rosen and Segev in SIAM J Comput 39(7):3058–3088, 2010), chosen-ciphertext-attack-secure encryption and deterministic encryption. Our results demonstrate a new set of applications of circularly secure encryption beyond fully homomorphic encryption and symbolic soundness. Finally, we show the plausibility of our assumptions by showing that the decisional Diffie–Hellman-based circularly secure scheme of Boneh et al. (Advances in cryptology—CRYPTO 2008, vol. 5157, Springer, 2008) and the subgroup indistinguishability-based scheme of Brakerski and Goldwasser (Advances in cryptology—CRYPTO 2010, vol. 6223, pp. 1–20, Springer, 2010) are both reproducible.  相似文献   
24.
We report on the concentration- and pump-dependent lifetimes of the spontaneous emission in Er3+-doped fibers and Er3+ -doped waveguides. In addition, we measure the concentration dependence of the 550-nm fluorescence due to excited state absorption (ESA)  相似文献   
25.
Satellite and avionics applications represent an ideal application for the tremendous performance, cost, space, andreliability benefits of MCMs. These advantages are only realized,however, if accompanied by an efficient test strategy whichverifies defect-free fabrication. This paper describes a methodology developed to test high performance VLSI CMOS ICs thathave been mounted onto a multi-chip silicon substrate. A teststrategy, which addresses testing from the wafer level through tothe populated substrate, is detailed. This strategy uses acombination of LSSD, AC LSSD-On-Chip Self Test, Deterministic Delay Fault Testing, and Design for Partitionability to ensure high testquality at a reasonable cost. The methodology is then contrastedto alternative approaches.  相似文献   
26.
非洲油气勘探区战略选择建议   总被引:3,自引:5,他引:3  
非洲不同类型的沉积盆地主要可归纳为:古、中生代挠曲盆地,中、新生代大陆边缘断陷盆地,板内裂谷盆地和大陆边缘进积三角洲盆地。通过盆地油气成藏条件地质综合评价、不同勘探阶段的类比和最终勘探潜力分析,对非洲的沉积盆地进行了划分,在此基础上,总结出非洲油气勘探区选择应遵循的原则。对于油气勘探长期战略选区,原则上,优选低成本油气远景区,即使存在高风险,但亦可获得高回报;对于油气勘探中期发展策略选区,应该寻找地质条件好的油气资源区,投资中短期高利润项目;对于油气勘探中短期发展策略选区,一般应优选中低成本、低风险、低利润且短期能获得油气发现和勘探突破的有利油气勘探区。图1表3参5  相似文献   
27.
In this paper we analyse issues associated with overloads in tandem switching systems in Common Channel Signalling (CCS) networks. In particular, we examine the need for, and effectiveness of, Automatic Congestion Control (ACC), a CCS mechanism which allows a congested switching system to inform adjacent CCS nodes of its level of overload, and subsequently controls the rate at which traffic is sent to the congested node. We demonstrate the critical need for end-offices and tandem switching systems to implement some form of ACC if network performance is to be maintained during congestion, especially in tandem exchanges. In addition, we find that the presently defined ACC should be expanded to allow more levels of congestion to be reported to adjacent nodes, so that a more effective, finer grained control is produced.  相似文献   
28.
We report the gain, noise figure, output saturation power, and conversion efficiency of a highly concentrated Er/sup 3+/-doped alumino silicate fiber amplifier. We obtain a gain per unit length of 1.0 dB/cm, which corresponds to the highest gain per unit length obtained in an Er/sup 3+/-doped fiber amplifier. The pump power threshold ranges from 2 to 5 mW, depending on the fiber length.  相似文献   
29.
The development of nanostructured microcapsules based on a biomimetic lipid bilayer membrane (BLM) coating of poly(sodium styrenesulfonate) (PSS)/poly(allylamine hydrochloride) (PAH) polyelectrolyte hollow microcapsules is reported. A novel engineered ion channel, gramicidin (bis‐gA), incorporated into the lipid membrane coating provides a functional capability to control transport across the microcapsule wall. The microcapsules provide transport and permeation for drug‐analog neutral species, as well as positively and negatively charged ionic species. This controlled transport can be tuned for selective release biomimetically by controlling the gating of incorporated bis‐gA ion channels. This system provides a platform for the creation of “smart” biomimetic delivery vessels for the effective and selective therapeutic delivery and targeting of drugs.  相似文献   
30.
This paper presents a new low-cost RF BIST (Built-In Self-Test) scheme that is capable of measuring input impedance, gain, noise figure and input return loss for a low noise amplifier (LNA) in RF systems. The RF BIST technique requires an additional RF amplifier and two peak detectors, and its output is a DC voltage level. The BIST circuit is designed using 0.18 μm SiGe technology. The test technique utilizes output DC voltage measurements and these measured values are translated into the LNA specifications such as input impedance and gain using the developed mathematical equations. Simulation results are presented for an LNA working at 5 GHz. Measurement data are compared with simulation results to validate the developed mathematical equations. The technique is simple and inexpensive. Jee-Youl Ryu received the BS and MS degrees in 1993 and 1997 from Pukyong National University in Electronic Engineering, Pusan, South Korea respectively. He also received the PhD degree in 2004 from Arizona State University in Electrical Engineering, Arizona, USA. He is currently with Samsung SDI Co., Ltd. His current research interests include RF IC design and testing, MMIC design and testing, analog IC design and testing, passives modeling, testing and analysis, and MEMS technology. Dr. Bruce Kim received the B.S.E.E. degree from the University of California, Irvine in 1981, the M.S. degree in electrical engineering from the University of Arizona in 1985, and the Ph.D. degree in electrical engineering from Georgia Institute of Technology in 1996. He was an Associate Professor at Arizona State University until 2005. Currently, he is an Associate Professor at The University of Alabama. His current research interests include RF IC testing, MEMS integration and VLSI circuits. He has been working on SiP testing technologies, package electrical modeling, and measurements of RF IC packages. Dr. Kim is a 1997 recipient of the National Science Foundation's CAREER Award and received the Meritorious Award from IEEE. He serves as the Chair of the IEEE CPMT Society TC-Electrical Test, associate editor of the IEEE Transactions on Advanced Packaging, associate editor of Design and Test of Computers, and program committee member of Electronic Components and Technology Conference. He is a senior member of IEEE.  相似文献   
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