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排序方式: 共有1038条查询结果,搜索用时 796 毫秒
951.
质量、工期和成本是工程项目三大主要控制目标,对于工程项目中质量-工期-成本综合均衡优化问题,传统的基于权重的决策方法存在各目标权重难以合理确定的问题.为此引入物理规划方法建立工程项目质量-工期-成本综合均衡优化模型.决策者只需设定各目标的偏好,即可通过该均衡优化模型获得符合决策者偏好的优化方案,使决策过程更加符合工程实际,避免了确定无实际物理意义的各目标权重的问题.通过桥梁工程实例验证了该方法的有效性和实用性. 相似文献
952.
Optimal financing and dividend control of the insurance company with proportional reinsurance policy
We consider the optimal control problem of the insurance company with proportional reinsurance policy. The management of the company controls the reinsurance rate, dividends payout as well as the equity issuance processes to maximize the expected present value of the dividends minus the equity issuance until the time of bankruptcy. This is the first time that the financing process in an insurance model has been considered, which is more realistic. To find the solution of the mixed singular-regular control problem, we firstly construct two categories of suboptimal models, one is the classical model without equity issuance, the other never goes bankrupt by equity issuance. Then we identify the value functions and the optimal strategies corresponding to the suboptimal models depending on the relationships between the coefficients. 相似文献
953.
Juan González-Hernández Raquiel R. López-Martínez J. Rubén Pérez-Hernández 《Mathematical Methods of Operations Research》2007,65(1):27-44
In this paper we consider Markov Decision Processes with discounted cost and a random rate in Borel spaces. We establish the
dynamic programming algorithm in finite and infinity horizon cases. We provide conditions for the existence of measurable
selectors. And we show an example of consumption-investment problem.
This research was partially supported by the PROMEP grant 103.5/05/40. 相似文献
954.
Classical Communication Cost and Probabilistic Remote Preparation of Four-Particle Entangled W State
HOU Kui SHI Shou-Hua 《理论物理通讯》2009,51(3):411-418
We present a scheme for probabilistic remote preparation of the four-particle entangled W state by using four partial entangled two-particle states as the quantum channel. In this scheme, if Alice (sender) performs four-particle projective measurements and Bob (receiver) adopts some appropriate unitary operation, the remote state preparation can be successfully realized with certain probability. The classical communication cost is also calculated. However, the success probability of preparation can be increased to 1 for four kinds of special states. 相似文献
955.
Madoori Mrinalini Nanaji Islavath Seelam Prasanthkumar Lingamallu Giribabu 《Chemical record (New York, N.Y.)》2019,19(2-3):661-674
Today's solar cells are exceptionally in demand whilst excess exploitation of natural fossil fuels. In this context, the first and second generation solar cells commercially available in market for more than decades however limitations in production cost and large–scale applications insist to generate inexpensive materials for fabrication. Thereby, organic materials based solar cells explored and emerging as third generation solar cells which possess flexibility, low cost and large‐scale applications. For example, organic photovoltaics, dye sensitized solar cells and perovskite (organic‐inorganic) solar cells (PSCs) are considered third generation solar cells wherein PSCs reached the record power conversion efficiency (PCE ~23 %) and durability assists great advantages for commercialization in near future. Moreover, we reported various global renowned companies involved producing the modules and materials for three generation solar cells, hence, majority of companies considered commercialization of perovskite based solar cells assist low cost photovoltaics to meet the current energy necessities and environmental safety. 相似文献
956.
Probabilistic remote preparation of a high-dimensional equatorial multiqubit with four-party and classical communication cost 下载免费PDF全文
This paper presents a protocol for probabilistic remote preparation of a high-dimensional equatorial multiqubit with four-party,consisting of a sender and three receivers.The quantum channel is composed of a partial entangled high-dimensional four-particle state.We calculate the successful total probability and the total classical communication cost required for this scheme.It is shown that both the entangled resources and classical communication cost are greatly reduced. 相似文献
957.
Based on the trajectory design of a mission to Saturn, this paper discusses four different trajectories in various swingby cases. We assume a single impulse to be applied in each case when the spacecraft approaches a celestial body. Some optimal trajectories ofEJS, EMS, EVEJS and EVVEJS flying sequences are obtained using five global optimization algorithms: DE, PSO, DP, the hybrid algorithm PSODE and another hybrid algorithm, DPDE. DE is proved to be supe- rior to other non-hybrid algorithms in the trajectory optimi- zation problem. The hybrid algorithm of PSO and DE can improve the optimization performance of DE, which is vali- dated by the mission to Saturn with given swingby sequences. Finally, the optimization results of four different swingby sequences are compared with those of the ACT of ESA. 相似文献
958.
研究可数状态空间任意行动空间非一致性有界费用马氏决策过程(MDP)的强平均最优,给出了使得每个常用的平均最优策略也是强平均最优的条件,并实质性的推广了Cavazos-Cadena和Fernandez-Gaucheran(Math. Meth. Oper. Res., 1996, 43: 281-300)的主要结果. 相似文献
959.
Classical Communication and Entanglement Cost in Preparing a Class of Multi-qubit States 总被引:1,自引:0,他引:1
PAN Gui-Xia LIU Yi-Min ZHANG Zhan-Jun 《理论物理通讯》2008,49(3):631-634
Recently, several similar protocols [J. Opt. B 4 (2002) 380; Phys. Lett. A 316 (2003) 159; Phys. Lett. A 355 (2006) 285; Phys. Lett. A 336 (2005) 317] for remotely preparing a class of multi-qubit states (i.e, α[0...0〉 +β[1... 1〉) were proposed, respectively. In this paper, by applying the controlled-not (CNOT) gate, a new simple protocol is proposed for remotely preparing such class of states. Compared to the previous protocols, both classical communication cost and required quantum entanglement in our protocol are remarkably reduced. Moreover, the difficulty of identifying some quantum states in our protocol is also degraded. Hence our protocol is more economical and feasible. 相似文献
960.
以低成本航姿测量系统为研究对象,针对四元数描述姿态时存在冗余的不足,提出使用三维独立矢量的修正的Rodrigues参数进行姿态解算,利用与其影子参数相互切换的方法解决了修正的Rodrigues参数在描述姿态时存在奇异的问题,根据系统中器件的特点,以陀螺零偏和修正的Rodrigues参数为状态向量,以加速度计、磁强计输出为观测向量建立了基于扩展Kalman滤波的姿态估计算法,避免了利用四元数进行姿态估计时状态误差方差阵产生奇异的问题,并在一定程度上减小了估计算法的计算量。最后通过全姿态以及摇摆基座数据仿真验证了算法的有效性。 相似文献