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针对电力系统经济负荷分配问题,提出一种有效的差分蜂群算法.受差分进化算法的启发,该算法基于差分进化操作改进了雇佣蜂的搜索方式,提高了探索能力和收敛速度.此外,提出一种有效的修复机制以保证新个体的可行性.该算法在带有阀点效应和多燃料特征的典型电力系统经济负荷分配问题上进行了测试.仿真结果验证了所提算法的有效性. 相似文献
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LIN Li-xing 《数字社区&智能家居》2008,(21)
XML能够使用得Internet上的数据交换变得更方便,XML与数据库一样,都能够作为信息存储的途径。当数据量不大的时候,比如完成一个在线备忘录,XML作为数据存储具有关系数据库所无法比拟的优势。在asp.net中能够利用.net类库提供的类及方法轻松地构建一个基于XML的在线备忘录。 相似文献
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Rónán Kennedy 《Information & Communications Technology Law》2008,17(2):95-106
The new industry of Massively Multi-Player Online Role-Playing Games (MMORPGs) brings together two sets of fictions: the interactive stories of shared computer games and the legal devices of intellectual property. In these virtual worlds, scarcity need not exist, but players tend to prefer the competition it creates. This leads to the development of property rights within the game world and players trading real money for virtual objects, ‘land’ and characters. This new phenomenon brings with it familiar legal problems such as theft, fraud and ownership disputes. Game creators also challenge the right of the players to claim ownership outside the game world. The volume and value of the items traded make real money trading an important area of current interest for intellectual property lawyers. Something is being traded, but does it fit neatly into existing conceptions of property rights and who owns it? Analysing the novel problems that result from various theoretical perspectives (utilitarianism, labour-desert theory and personality theory) leads to the conclusion that with time, we will see the development of property rights for players in online games. This connects with a growing understanding that the traditional conception of copyright law dealing with creative work generated by the solitary author is becoming less appropriate in the new creative spaces that information and communications technology brings, where individuals are both consumer and producer. In virtual worlds, new forms of intellectual property, and perhaps even new rights, are taking shape. 相似文献
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In this note, we prove that both problems studied by Cheng et al. [Cheng, T. C. E., Hsu, C.-J., & Yang, D.-L. (2011). Unrelated parallel-machine scheduling with deteriorating maintenance activities. Computers and Industrial Engineering, 60, 602–605] can be solved in O(nm+3) time no matter what the processing time of a job after a maintenance activity is greater or less than its processing time before the maintenance activity, where m is the number of machines and n is the number of jobs. 相似文献
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《Ergonomics》2012,55(2):151-162
The paper attempts to list the most important fields in which research on human factors in road transport is required. The importance of improving the efficiency of road transport is emphasized, and the figures for road casualties are quoted to demonstrate the need to study the behaviour of cyclists, motor-cyclists and pedestrians as well as motorists. The problems on which research is required are grouped under the six headings of perception, communication of information, control of the vehicle, comfort, protection of occupants, and behaviour of drivers. Subjects regarded as of particular interest are (1) the communication of information to the driver, (2) the design of the vehicle to improve control by the driver, (3) crash injury protection for the motorist and for the motor-cyclist, and (4) the study of the driving task. 相似文献