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91.
研究基于关键资源优先的单元化“装卸、搬运、装卸” 三级作业链的调度问题. 在已知关键资源调度方案的条件下, 将两个非关键各作业级的调度问题分别转化为最小单位流问题, 并建立相应的0/1 整数规划模型求解. 为求解大规模问题, 提出三级装卸搬运的分时协调策略. 参照宁波港码头数据, 设计面向集装箱码头的仿真算例, 实验结果验证了所提出模型和策略的有效性.
相似文献92.
Jun Yang Wei E. I. Sha Hongyang Chao Zhu Jin 《Multimedia Tools and Applications》2016,75(11):6189-6205
A novel framework to construct an efficient sensing (measurement) matrix, called mixed adaptive-random (MAR) matrix, is introduced for directly acquiring a compressed image representation. The mixed sampling (sensing) procedure hybridizes adaptive edge measurements extracted from a low-resolution image with uniform random measurements predefined for the high-resolution image to be recovered. The mixed sensing matrix seamlessly captures important information of an image, and meanwhile approximately satisfies the restricted isometry property. To recover the high-resolution image from MAR measurements, the total variation algorithm based on the compressive sensing theory is employed for solving the Lagrangian regularization problem. Both peak signal-to-noise ratio and structural similarity results demonstrate the MAR sensing framework shows much better recovery performance than the completely random sensing one. The work is particularly helpful for high-performance and lost-cost data acquisition. 相似文献
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Front cover: MALDI mass spectrometry imaging: A cutting‐edge tool for fundamental and clinical histopathology
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Reactive power compensation is an important issue in the control of electric power system. Reactive power from the source increases the transmission losses and reduces the power transmission capability of the transmission lines. Moreover, reactive power should not be transmitted through the transmission line to a longer distance. Hence Flexible AC Transmission Systems (FACTS) devices such as static compensator (STATCOM) unified power flow controller (UPFC) and static volt–ampere compensator (SVC) are used to alleviate these problems. In this paper, a voltage source converter (VSC) based STATCOM is developed with PI and Artificial Neural Network Controller (ANNC). The conventional PI controller has more tuning difficulties while the system parameter changes, whereas a trained neural network requires less computation time. The ANNC has the ability to generalize and can interpolate in between the training data. The ANNC designed was tested on a 75 V, ±3KVAR STATCOM in real time environment via state-of-the-art of digital signal processor advanced control engineering (dSPACE) DS1104 board and it was found that it was producing better results than the PI controller. 相似文献
97.
计算机操作系统课程教学改革的研究与探讨 总被引:2,自引:0,他引:2
分析了计算机操作系统课程教学中产生的问题和原因,从课程内容体系组建、教学方法、教学手段以及实践教学环节制定等多个方面对该课程的改革进行了深入研究和探讨,力求通过教学改革加强对学生思维方式、创新意识和能力的培养,进一步提高课程的教学质量。 相似文献
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加强信息安全风险评估工作的研究 总被引:2,自引:0,他引:2
简要介绍国内外信息安全风险评估工作的发展过程,指出各应用领域或各组织进行信息安全风险评估的重要性。阐述了信息安全风险评估需要解决的问题,介绍目前在信息安全风险评估领域所采取的主要方法,并对这些方法进行分析和评价。探讨信息安全风险评估工作的流程,并展望了信息安全风险评估的发展前景。 相似文献
99.
With more and more real deployments of wireless sensor network applications, we envision that their success is nonetheless determined by whether the sensor networks can provide a high quality stream of data over a long period. In this paper, we propose a consistency-driven data quality management framework called Orchis that integrates the quality of data into an energy efficient sensor system design. Orchis consists of four components, data consistency models, adaptive data sampling and process protocols, consistency-driven cross-layer protocols and flexible APIs to manage the data quality, to support the goals of high data quality and energy efficiency. We first formally define a consistency model, which not only includes temporal consistency and numerical consistency, but also considers the application-specific requirements of data and data dynamics in the sensing field. Next, we propose an adaptive lazy energy efficient data collection protocol, which adapts the data sampling rate to the data dynamics in the sensing field and keeps lazy when the data consistency is maintained. Finally, we conduct a comprehensive evaluation to the proposed protocol based on both a TOSSIM-based simulation and a real prototype implementation using MICA2 motes. The results from both simulation and prototype show that our protocol reduces the number of delivered messages, improves the quality of collected data, and in turn extends the lifetime of the whole network. Our analysis also implies that a tradeoff should be carefully set between data consistency requirements and energy saving based on the specific requirements of different applications. 相似文献
100.