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31.
We examine the problem of building or fortifying a network to defend against enemy attacks in various scenarios. In particular,
we examine the case in which an enemy can destroy any portion of any arc that a designer constructs on the network, subject
to some interdiction budget. This problem takes the form of a three-level, two-player game, in which the designer acts first
to construct a network and transmit an initial set of flows through the network. The enemy acts next to destroy a set of constructed
arcs in the designer’s network, and the designer acts last to transmit a final set of flows in the network. Most studies of
this nature assume that the enemy will act optimally; however, in real-world scenarios one cannot necessarily assume rationality
on the part of the enemy. Hence, we prescribe optimal network design algorithms for three different profiles of enemy action:
an enemy destroying arcs based on capacities, based on initial flows, or acting optimally to minimize our maximum profits
obtained from transmitting flows. 相似文献
32.
33.
Security of the Cao-Li public key cryptosystem 总被引:1,自引:0,他引:1
Lim Lek Heng 《Electronics letters》1998,34(2):170-172
The author shows that the Cao-Li cryptosystem proposed [1991] is not secure. Its private key can be reconstructed from its public key using elementary means such as LU-decomposition and the Euclidean algorithm 相似文献
34.
35.
In the design of a digital filter, the frequency response is often optimized to meet a given set of specifications on a dense grid of frequency points. The density of the frequency grid points must be sufficiently high so that the frequency response of the filter does not violate the specifications at frequencies in between the grid points. However, the computational complexity of the design process and the storage requirements of the computer increase with the number of frequency grid points. We propose a novel dynamic: grid point allocation technique for the design of minimax optimum FIR filter. It uses a sparse frequency grid but will produce a design that is the same as one designed on very dense frequency grid points. It requires significantly less computer time and memory resources compared with fixed grid point algorithms 相似文献
36.
Analysis and characterization of traveling-wave electrode in electroabsorption modulator for radio-on-fiber application 总被引:1,自引:0,他引:1
Jiyoun Lim Young-Shik Kang Kwang-Seong Choi Jong-Hyun Lee Sung-Bock Kim Jeha Kim 《Lightwave Technology, Journal of》2003,21(12):3004-3010
Comparing with a lumped electroabsorption modulator (EAM), we show the merits of a long EAM with traveling-wave electrode with high radio-frequency (RF) gain that could be used in high-frequency analog application. By terminating the RF output port with the characteristic impedance of 30 /spl Omega/, the device exhibited a large enhancement of 6 dB above 10 GHz in the electrical-to-optical response and a wide fractional bandwidth as estimated from simulation. In addition, an input impedance matching circuit of stub embedded on the device chip was found to be very effective for improving RF characteristics in the narrow band of frequency. 相似文献
37.
The photonic quantum ring (PQR) laser is a three dimensional whispering gallery (WG) mode laser and has anomalous quantum wire properties, such as microampere to nanoampere range threshold currents and √T‐dependent thermal red shifts. We observed uniform bottom emissions from a 1‐kb smart pixel chip of a 32×32 InGaAs PQR laser array flip‐chip bonded to a 0.35 µm CMOS‐based PQR laser driver. The PQR‐CMOS smart pixel array, now operating at 30 MHz, will be improved to the GHz frequency range through device and circuit optimization. 相似文献
38.
JaeHyunKim JounHoLee JiChulLim ChangHoonLee MooHyoungSong JuYeonYoon HeeDongChoi JeomJaeKim ChangHoOh SangDeogYeo 李路海 《现代显示》2004,31(5):31-33
薄膜晶体管液晶电视(TFT-LCD TV)因为具有薄、轻、紧凑和可随意放置的特点,已经占据了大部分电视机市场。除了这些物理特性以外,最重要的特性是已具有了良好像质的对比度。为了将对比度提高到1:600以上,对偏振片膜、背光源板、滤色片树脂、电极锥角和摩擦条件等都进行了研究。优化的背光板组合,光滑的电极锥角和摩擦方法的控制是提高对比度的主要控制因素。应用新开发的滤色片树脂,对获得高对比度最为有效。 相似文献
39.
Teik-Cheng Lim 《Czechoslovak Journal of Physics》2004,54(5):553-559
A theoretical relation between the Bauer-Maysenholder-Seeger (BMS) and the Biswas-Hamann (BH) potential function has been developed herein for the case of 2-body interaction. By equating derivatives of these two potential functions for the 2-body part, a loose form of BMS is expressed in terms of BH parameters with a scaling factor. The validity of the developed parametric relationships has been graphically demonstrated, and the suitability discussed with reference to the extent and direction of bond distortion. 相似文献
40.
Electrically small spiral ground planes for a monopole and an electrically small antenna have been designed for HF ground wave transmission. Prototype ground planes have been built and tested. For the monopole, the transmission loss of the designed ground plane is 6 dB better than that of the same size ground radials. For the electrically small antenna, the transmission loss of the designed ground plane is 7 dB better than that of the same size solid ground plane at the antenna's operating frequency. 相似文献