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1.
We generalize the Negation-as-Failure procedure for disjunctive logic programming. Then we compare our method with related methods in the literature. We also propose a new completion theory for disjunctive logic programs which allows some program clauses to have inclusive meaning and the others exclusive meaning. 相似文献
2.
On the SEP of Cooperative Diversity with Opportunistic Relaying 总被引:1,自引:0,他引:1
We analyze the exact symbol error probability (SEP) of cooperative diversity with opportunistic amplify-and-forward (AF) relaying. The benefit of this opportunism to the SEP is assessed by comparing with maximal ratio combining of orthogonal multiple AF relay transmissions. 相似文献
3.
Feng Wang Chong-Wah Ngo Ting-Chuen Pong 《Multimedia, IEEE Transactions on》2008,10(5):926-935
4.
A Hammerstein-based dynamic model for hysteresis phenomenon 总被引:2,自引:0,他引:2
The Hammerstein configuration, which includes a nonlinear static block followed by a linear dynamic block, is applied to model the rate-dependent and temperature-dependent hysteresis phenomenon. The nonlinear static block is realized by a modified Preisach model, which includes both the irreversible and reversible components of magnetization. The linear dynamic block is realized by a low-pass filter, which takes into account the rate-dependent effects of hysteresis. Temperature dependencies are incorporated into the model by fitting the model parameters as piecewise-linear functions of temperature. A procedure is described for the extraction of a single set of model parameters over the frequency, amplitude, and temperature ranges of interest. The theory is verified experimentally 相似文献
5.
Sien Chi Jeng-Cherng Dung Senfar Wen 《Lightwave Technology, Journal of》1995,13(6):1121-1126
The maximum bit rate of a soliton communication system with lumped amplifiers and optical filters is considered. When the dispersion of the fiber varies from one amplifier spacing to another amplifier spacing, the maximum bit rate is significantly reduced. To overcome the effect, the amplitude of the soliton is amplified so that it is still the average soliton corresponding to the fiber dispersion for an amplifier spacing. Thus, the maximum bit rate is only slightly less than that without the dispersion variations. For a given distance, the maximum bit rate limited by the stability and soliton interaction is obtained. The result is compared with that limited by the Gordon-Haus effect. For shorter transmission distance, the maximum bit rate is limited by the stability and soliton interaction. For longer transmission distance, the maximum bit rate is limited by the Gordon-Haus effect 相似文献
6.
Nguyen-Huy Dung Pardo Marie-Paule Dogguy.Smiri Leïla 《Materials Research Bulletin》1982,17(3):293-300
The Mn0.23Ga1.85S3 phase belongs to the solid solution , stable at low temperature in the Ga2S3MnS system. It is hexagonal superstructure of the wurtzite, with the Ga2S3α′ type (; Z = 6; space groupe P61 or P65). Its crystal structure has been refined by the least squares method to a final R = 0.06 with 323 independant reflections. This structure is closely related to Ga2S3 α described by Hahn and Frank, and differs only by the partial occupation of the vacant metal site of Ga2S3 by Mn atoms in statistical disorder. 相似文献
7.
A multiserver queueing model of access control strategies for a wideband integrated services digital network (ISDN) is considered. There are two types of service requests (SRs): Type 1 SR requires b servers (basic bandwidth units, BBUs) of the c available servers, while Type 2 SR requires a single server. Both types of SRs are queuable in two separate infinite-size buffers. A Type 1 SR is allowed to seize d (⩽b ) servers at first and then acquire additional servers as they become available to meet the original requirement of b servers. The arrival processes of both types of SRs are Poisson and the service times are exponentially distributed with mean b /d μ1 and 1/μ2 for Type 1 SR and Type 2 SR, respectively. Preemptive and nonpreemptive priority disciplines with movable boundary are analyzed using the Neuts' matrix-analytic approach. Numerical examples of the queue length distribution and the mean waiting time of the SRs are presented 相似文献
8.
9.
Gerosa G. Gary S. Dietz C. Dac Pham Hoover K. Alvarez J. Sanchez H. Ippolito P. Tai Ngo Litch S. Eno J. Golab J. Vanderschaaf N. Kahle J. 《Solid-State Circuits, IEEE Journal of》1994,29(12):1440-1454
A 28 mW/MHz at 80 MHz structured-custom RISC microprocessor design is described. This 32-b implementation of the PowerPC architecture is fabricated in a 3.3 V, 0.5 μm, 4-level metal CMOS technology, resulting in 1.6 million transistors in a 7.4 mm by 11.5 mm chip size. Dual 8-kilobyte instruction and data caches coupled to a high performance 32/64-b system bus and separate execution units (float, integer, loadstore, and system units) result in peak instruction rates of three instructions per clock cycle. Low-power design techniques are used throughout the entire design, including dynamically powered down execution units. Typical power dissipation is kept under 2.2 W at 80 MHz. Three distinct levels of software-programmable, static, low-power operation-for system power management are offered, resulting in standby power dissipation from 2 mW to 350 mW. CPU to bus clock ratios of 1×, 2×, 3×, and 4× are implemented to allow control of system power while maintaining processor performance. As a result, workstation level performance is packed into a low-power, low-cost design ideal for notebooks and desktop computers 相似文献
10.
Gill J.J.-Y. Ngo L.V. Nelson P.R. Chang-Jin Kim 《Journal of microelectromechanical systems》1998,7(1):114-121
This paper describes the concept, analysis, fabrication, and testing of a new anchor for surface-micromachined beams. The anchor is designed to eliminate the extra spring effect at the step-up anchor common in conventional surface-micromachined beams, so that the boundary condition follows the ideal anchoring condition more accurately. The idea is to form a reinforcement hump at the beam anchor through a minor modification in the sacrificial-layer mask. No modification in the fabrication process is necessary. Formation of the reinforcement hump is tested using the multiuser MEMS Process (MUMP) foundry service at the Microelectronics Center of North Carolina (MCNC). The effectiveness of the new anchor is analyzed by finite-element analysis based on the actual anchor geometry obtained from the fabrication directly. Experimental verification is provided by making overhanging microcantilever pairs, one with the new anchor and the other with conventional, through MUMP's and postprocessing and comparing their frequency responses. Small-signal frequency response measurements are made with a modified Michaelson interferometer. Resonant frequency of a 2-μm-thick 300-μm-long polysilicon cantilever with the new anchor differed by less than 0.1% from the ideal anchor case. In comparison, the resonant frequency of the same beam with a conventional anchor is off by over 1% 相似文献