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961.
Motivated by challenges in the smartphone manufacturing industry, we develop a dynamic production ramp-up model that can be applied to economically satisfy nonstationary demand for short-life-cycle products by high-tech companies. Due to shorter life cycles and more rapid evolution of smartphones, production ramp-up has been increasingly critical to the success of a new smartphone. In the production ramp-up, the key challenge is to match the increasing capacity to nonstationary demand. The high-tech smartphone manufacturers are urged to jointly consider the effect of increasing capacity and decreasing demand. We study the production planning problem using a high-dimensional Markov decision process (MDP) model to characterize the production ramp-up. To address the curse of dimensionality, we refine Monte Carlo tree search (MCTS) algorithm and theoretically analyze its convergence and computational complexity. In a real case study, we find that the MDP model achieves revenue improvement by stopping producing the existing product earlier than the benchmark policy. In synthetic instances, we validate that the proposed MCTS algorithm saves computation time without loss of solution quality compared with traditional value iteration algorithm. As part of the Lenovo production solution, our MDP model enables high-tech smartphone manufacturers to better plan the production ramp-up. 相似文献
962.
We study optimal pricing for tandem queueing systems with finite buffers. The service provider dynamically quotes prices to incoming price sensitive customers to maximize the long-run average revenue. We present a Markov decision process model for the optimization problem. For systems with two stations, general-sized buffers, and two or more prices, we describe the structure of the optimal dynamic pricing policy and develop tailored policy iteration algorithms to find an optimal pricing policy. For systems with two stations but no intermediate buffer, we characterize conditions under which quoting either a high or a low price to all customers is optimal and provide an easy-to-implement algorithm to solve the problem. Numerical experiments are conducted to compare the developed algorithms with the regular policy iteration algorithm. The work also discusses possible extensions of the obtained results to both three-station systems and two-station systems with price and congestion sensitive customers using numerical analysis. 相似文献
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964.
针对各类油库传统实物沙盘存在的诸多问题,提出以传统沙盘堆制理论为依据,以后台数据库为基础,结合现代先进的虚拟现实技术来研制油库三维电子沙盘。在介绍了系统功能需求的基础上,阐述了系统开发环境和系统结构,详细分析了系统实现的步骤:素材收集和处理、三维建模及优化处理、三维模型集成显示与碰撞检测、后台数据库连接设计,并指出了系统的发展建议。 相似文献
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967.
原始的全向图存在严重的同心圆环状变形,通常需展开为更适合人眼观察的柱面全景图像。结合折反射全向成像特点,提出一种基于双向映射的全向图展开为柱面全景图像的插值方法,通过光路跟踪得到图像间的坐标映射关系,将所要生成的柱面全景图中每一点正向映射到原始的全向图中,确定插值邻域点;将这些邻域点逆向投影到柱面全景图中,针对邻域点在柱面全景图中呈非网格型分布的特点,采用非均匀二维插值算法进行图像插值运算。该方法既准确地定位插值邻域点,又避免了全向图的非线性畸变对邻域点权重计算的不利影响。实验证明该方法能有效提高插值精度和展开后图像的质量。 相似文献
968.
Plug‐in hybrid electric vehicles (PHEVs), upon market penetration, will create additional recharging loads to the electric power systems. This article considers different recharging scenarios and uses game theoretic models to study the potential impact of the recharging loads on locational marginal prices (wholesale electricity prices). Computational results from a Pennsylvania‐New Jersey‐Maryland Interconnection case study show that, under the existing recharging infrastructures, even a small magnitude of load increase caused by PHEV recharging could have a significant undesirable impact on locational marginal prices. The impact could be mitigated to a varying extent by the availability of possible future recharging infrastructures, including realtime pricing recharging meters, battery stations, or vehicle‐to‐grid technology.© 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
969.
在超凸度量空间利用广义度量KKM映象原理的特性得到一类新的广义极大极小不等式,并进一步借助这类极大极小不等式,在更广泛的条件下,获得鞍点问题的一个新的存在性结果。 相似文献
970.