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231.
Shixin ZHU Xiaoshan KAI 《系统科学与复杂性》2008,21(1):60-66
The Hamming distances of all negacyclic codes of length 28 over the Gaiois ring GR (2^α, m) are given. In particular, the Lee distances of all negacyclic codes over Z4 of length 2^s are obtained. The Gray images of such negacyclic codes over Z4 are also determined under the Gray map. 相似文献
232.
Traditional Chinese medicine (TCM) has a rich knowledge about human health and disease by its special way evolved along a very long history. As modern medicine is achieving much progress, arguments and disputes toward TCM never end. To avoid losing precious knowledge of living TCM masters, endeavors have been engaged to systematic collection of those knowledge of TCM masters, such as their growth experiences, effective practical cases toward diseases and typical therapeutic principles and methods. Knowledge mining methods have been expected to explore some useful or hidden patterns to unveil some mysteries of the TCM system. In the paper, some computerized methods are applied toward those collected materials about some living TCM masters in China mainland to show a different way of exposing essential ideas of those TCM masters by correspondence visualization which aims to help people understand TCM holistic views toward disease and body, and facilitate tacit knowledge transfer and sense-making of the essence of TCM. The work is one kind of qualitative meta-synthesis of TCM masters' knowledge. 相似文献
233.
在分析经典回购合约的回购价格、回构批量及最高回购率的基础上,进一步讨论当供应商实际允许执行的最高回购率风险波动时,零售商相应的订货策略。建立了回购率风险波动时以利润最大化为目标的数学模型;分别讨论了有无风险波动等3种情况下零售商及供应链总体利润变化。得出了当相关参数风险波动时,零售商相应的最优订货策略。当回购率风险波动时,供应链成员及供应链总的期望利润都会下降。而回购率风险波动零售商却不做相应订货策略调整的话,整个供应链的期望利润跟经典回购时一样,但是零售商的利润会部向供应商转移,产生利润损失。 相似文献
234.
This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing (STAP) in airborne multi-channel early-warning radar. Based on this clutter model, STAP performance is then analyzed from the perspective of covariance matrix tapering (CMT). For STAP performance degradation due to array rotation, a determinate compensation method is proposed based on the CMT method. Numerical examples are provided to verify the analysis and the proposed compensation method. 相似文献
235.
A compressed sensing (CS) based channel estimation algorithm is proposed by using the delay-Doppler sparsity of the fast fading channel. A compressive basis expansion channel model with sparsity in both time and frequency domains is given. The pilots in accordance with a novel random pilot matrix in both time and frequency domains are sent to measure the delay-Doppler sparsity channel. The relatively nonzero channel coefficients are tracked by random pilots at a sampling rate significantly below the Nyquist rate. The sparsity channels are estimated from a very limited number of channel measurements by the basis pursuit algorithm. The proposed algorithm can effectively improve the channel estimation performance when the number of pilot symbols is reduced with improvement of throughput efficiency. 相似文献
236.
The problem of robust H∞ control for uncertain neutral stochastic systems with time-varying delay is discussed. The parameter uncertaintie is assumed to be time varying norm-bounded. First, the stochastic robust stabilization of the stochastic system without disturbance input is investigated by nonlinear matrix inequality method. Then, a full-order stochastic dynamic output feedback controller is designed by solving a bilinear matrix inequality (BMI), which ensures a prescribed stochastic robust H∞ performance level for the resulting closed loop system with nonzero disturbance input and for all admissible uncertainties. An illustrative example is provided to show the feasibility of the controller and the potential of the proposed technique. 相似文献
237.
The reverse construction and analysis of the networks of molecular interactions are essential for understanding their functions
within cells. In this paper, a logic network model is constructed to investigate the complicated regulation mechanism of shoot
genes of Arabidopsis Thaliana in response to stimuli. The dynamics of the complicated logic network is analyzed, discussed,
and simulated. The simulation results show that the logic network of the active genes of shoot eventually evolves into eleven
attractors under the stimuli, including five 1-periodic and six 2-periodic attractors. Our work provides valuable reference
and guidance for biologists to understand and explain Arabidopsis’ response to external stimuli by experiments. 相似文献
238.
<正> This paper considers finite-time χ-consensus problem for a multi-agent system with firstorderindividual dynamics and switching interaction topologies.Several distributed finite-time consensusrules are constructed for multi-agent dynamics in a unified way with the help of Lyapunovfunction and graph theory as well as homogeneity.Time-invariant non-smooth forms of finite-timeneighbor-based controllers are proposed and a numerical example is shown for illustration. 相似文献
239.
<正> This paper formulates and analyzes a line search method for general nonlinear equalityconstrained optimization based on filter methods for step acceptance and secant methods for searchdirection.The feature of the new algorithm is that the secant algorithm is used to produce a searchdirection,a backtracking line search procedure is used to generate step size,some filtered rules areused to determine step acceptance,second order correction technique is used to reduce infeasibility andovercome the Maratos effect.Global convergence properties of this method are analyzed:under mildassumptions it is showed that every limit point of the sequence of iterates generated by the algorithmis feasible,and that there exists at least one limit point that is a stationary point for the problem.Moreover,it is also established that the Maratos effect can be overcome in our new approach by addingsecond order correction steps so that fast local superlinear convergence to a second order sufficient localsolution is achieved.Finally,the results of numerical experiments are reported to show the effectivenessof the line search filter secant method. 相似文献
240.
China's aerospace enterprises carry on the multinational operation and participate in the international competition and the international division of labor and cooperation positively. This article first analyzs China aerospace enterprises' binary multinational business control objective and constructes its model. Then the article analyzes the tangible and intangible control mechanism of China aerospace enterprises' binary multinational operation respectively. Finally, the article constructs the model of China aerospace enterprises' binary multinational operation mechanisms. 相似文献