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1.
BDI模型能够很好地解决在特定环境下的Agent的推理和决策问题,但在动态和不确定环境下缺少决策和学习的能力。强化学习解决了Agent在未知环境下的决策问题,却缺少BDI模型中的规则描述和逻辑推理。针对BDI在未知和动态环境下的策略规划问题,提出基于强化学习Q-learning算法来实现BDI Agent学习和规划的方法,并针对BDI的实现模型ASL的决策机制做出了改进,最后在ASL的仿真平台Jason上建立了迷宫的仿真,仿真实验表明,在加入Q-learning学习机制后的新的ASL系统中,Agent在不确定环境下依然可以完成任务。 相似文献
2.
In this paper, we study scheduling games under mixed coordination mechanisms on hierarchical machines. The two scheduling policies involved are ‐ and ‐, where ‐ (resp., ‐) policy sequences jobs in nondecreasing order of their hierarchies, and jobs of the same hierarchy in nonincreasing (resp., nondecreasing) order of their processing times. We first show the existence of a Nash equilibrium. Then we present the price of anarchy and the price of stability for the games with social costs of minimizing the makespan and maximizing the minimum machine load. All the bounds given in this paper are tight. 相似文献
3.
Ye Wan Jun Tan Guangling Song Chuanwei Yan 《Metallurgical and Materials Transactions A》2006,37(7):2313-2316
The focused ion beam technique was employed to investigate the atmospheric corrosion morphology of AZ91D. It was found that
the α matrix of the alloy was preferentially corroded in the areas adjacent to intermetallic phases. The most interesting
finding was that the corrosion products in corrosion cavities were pelletlike, which has never been reported before. 相似文献
4.
易前 《水利水电工程设计》2006,25(4):12-13
镜面混凝土是水电工程建设中新兴的一门施工技术,在乌江索风营水电站地下厂房岩锚梁混凝土施工中采用了镜面混凝土,这在技术上是一次大胆的尝试和创新,既满足了功能上的要求,同时也达到了美观和装饰地下厂房的效果,为今后水电工程施工中广泛采用镜面混凝土技术提供了样本和宝贵经验。 相似文献
5.
P(DBF-VA)型柴油低温流动性改进剂的研制 总被引:1,自引:1,他引:0
针对新疆地产柴油蜡含量较高的特点,以游离基聚合法合成了富马酸双链混合酯和醋酸乙烯酯共聚物型[P(DBF-VA)]柴油低温流动改进剂,利用正交实验研究了单体配比,引发剂用量,溶剂用量,聚合温度对聚合物降冷滤效果的影响。共聚物用IR进行表征,利用XRD初步探讨了该降凝剂的降凝机理。结果表明:该剂能使吐哈—10~#、0~#柴油冷滤点降低10℃和7℃;使独山子0~#柴油冷滤点下降12℃;使石化0~#柴油冷滤点下降8℃;使克拉玛依0~#柴油的冷滤点下降8℃。 相似文献
6.
7.
Uplink scheduling in wireless systems is gaining importance due to arising uplink intensive data services (ftp, image uploads
etc.), which could be hampered by the currently in-built asymmetry in favor of the downlink. In this work, we propose and
study algorithms for efficient uplink packet-data scheduling in a CDMA cell. The algorithms attempt to maximize system throughput
under transmit power limitations on the mobiles assuming instantaneous knowledge of user queues and channels. However no channel
statistics or traffic characterization is necessary. Apart from increasing throughput, the algorithms also improve fairness
of service among users, hence reducing chances of buffer overflows for poorly located users.
The major observation arising from our analysis is that it is advantageous on the uplink to schedule “strong” users one-at-a-time,
and “weak” users in larger groups. This contrasts with the downlink where one-at-a-time transmission for all users has shown
to be the preferred mode in much previous work. Based on the optimal schedules, we propose less complex and more practical
approximate methods, both of which offer significant performance improvement compared to one-at-a-time transmission, and the
widely acclaimed Proportional Fair (PF) algorithm, in simulations. When queue content cannot be fed back, we propose a simple modification of PF, Uplink PF (UPF), that offers similar improvement.
Hereafter, we refer to users with low recieved power at the base even when transmitting at peak transmit power as “weak” users,
and the strongly recieved users at the base as “strong” users.
Krishnan Kumaran is currently a member of the Complex Systems Modeling section in the Corporate Strategic Research of ExxonMobil Corp., Clinton,
NJ. Formerly, he was a Member of Technical Staff in the Mathematics of Networks and Systems Research Department at Bell Labs
in Murray Hill, NJ, where his research interests were in modeling, analysis and simulation of design, resource management
and scheduling issues in telecommunication networks.
Lijun Qian is an assistant professor in the Department of Electrical Engineering at Prairie View A&M University. He received his B.S.
from Tsinghua University in Beijing, M.S. from Technion-Israel Institute of Technology, and Ph.D. from WINLAB, Rutgers University,
all in electrical engineering. Before joining PVAMU, he was a researcher at Networks and Systems Research Department of Bell
Labs in Murray Hill, NJ. His major research interests are in wireless communications and networking technologies, especially
in radio resource management, protocol design, TCP/RLP optimization and MPLS traffic engineering. 相似文献
8.
9.
Chong D. Y. R. Lim B. K. Rebibis K. J. Pan S. J. Sivalingam K. Kapoor R. Sun A. Y. S. Tan H. B. 《Advanced Packaging, IEEE Transactions on》2006,29(4):674-682
The recent advancement in high- performance semiconductor packages has been driven by the need for higher pin count and superior heat dissipation. A one-piece cavity lid flip chip ball grid array (BGA) package with high pin count and targeted reliability has emerged as a popular choice. The flip chip technology can accommodate an I/O count of more than five hundreds500, and the die junction temperature can be reduced to a minimum level by a metal heat spreader attachment. None the less, greater expectations on these high-performance packages arose such as better substrate real estate utilization for multiple chips, ease in handling for thinner core substrates, and improved board- level solder joint reliability. A new design of the flip chip BGA package has been looked into for meeting such requirements. By encapsulating the flip chip with molding compound leaving the die top exposed, a planar top surface can be formed. A, and a flat lid can then be mounted on the planar mold/die top surface. In this manner the direct interaction of the metal lid with the substrate can be removed. The new package is thus less rigid under thermal loading and solder joint reliability enhancement is expected. This paper discusses the process development of the new package and its advantages for improved solder joint fatigue life, and being a multichip package and thin core substrate options. Finite-element simulations have been employed for the study of its structural integrity, thermal, and electrical performances. Detailed package and board-level reliability test results will also be reported 相似文献
10.
世界原油质量趋势及我国面临的挑战 总被引:3,自引:0,他引:3
评述了世界原油质量趋势、我国重质油现状以及我国加工含硫原油的现状和前景。 相似文献