吟到中华以外天——论黄遵宪的海外旅游诗

黄遵宪是近代思想启蒙运动的先驱和变法维新的领袖之一,也是当时诗坛光焰夺目的巨星。所著《人境庐诗草》中除反映时代风云的纪事诗外,大量写海外见闻的旅游诗,境界一新,成就突出。诗中描写东西洋各国的山川名胜和风俗人情,寄慨时事,向往民主,表现出先进、开放的全球意识和勇于探索、敢于革新的精神,给传统诗歌注入蓬勃的活力。在艺术上,诗人继承传统,厚植根基,开拓创新,形成雄奇壮美和多姿多彩的风格,写各种景物、人物,形象生动,语言精妙。黄诗的思想品格和艺术成就对当今的诗歌创作有多方面的启示,随着国门的开放,旅游诗有着更为远大的前景。     

Some Results on Node Lifting of TSP Inequalities

We can define important classes of TSP inequalities by performing Naddef and Rinaldi's node lifting operation on simple TSP inequalities.We present some new insights into the node lifting operation, namely that 1-node lifting of cut based inequalities always has a geometric interpretation if a certain claw-free condition which is satisfied by most of these TSP inequalities is met. We go on to show that node lifting of the subtour elimination inequalities does not yield any new inequalities.     

从旅游观念看明代文人士大夫的闲暇生活

自明代中期以后,对旅游的肯定已成一时之风,而旅游则已经成为文人士大夫闲暇生活的重要组成部分.文章通过对明代士大夫旅游观念系统的梳理,指出文人与道学家在旅游观念上具有很大的差异性.在此基础上,文章对士大夫的旅游体验又作了详细的分析,并对明代的游人进行了具体的细化,将其归为贵人之游、豪士之游、布衣之游与民众之游四类.     

基于系统仿真的高温行车空调器性能分析与实验研究

建立空调器部件和系统的仿真模型,将系统仿真技术应用到高温行车空调器的研制过程中,采用理论计算和实验验证相结合的方法研究产品的运行性能.通过数值求解,得到制冷系统循环的平衡点.通过模拟曲线和测试结果的对比分析,对仿真模型进行验证和完善.结果表明,高温行车空调器动态运行时,系统的各项参数均发生不同程度的波动,其中变化最显著的是制冷量和压缩机排气温度.在高温行车空调器系统设计过程中,应采取有效措施降低排气温度,以提高空调器整体性能.     

行波管与速调管的离子噪声分析

从波动理论与运动学理论出发,采用小信号近似,分析了行波管与速调管中的离子噪声现象,推导出基于离子张驰振荡引起的相位噪声表达式,并对离子噪声形成的相位噪声特性进行分析,指出随着电位波动的幅度增大,相位噪声同时增加;载波信号频率越高,相位噪声越高。     

The Flow Shop Scheduling Polyhedron with Setup Times

This paper addresses the problem of improving the polyhedral representation of a certain class of machine scheduling problems. Despite the poor polyhedral representation of many such problems in general, it is shown that notably tighter linear programming representations can be obtained for many important models. In particular, we study the polyhedral structure of two different mixed-integer programming formulations of the flow shop scheduling problem with sequence-dependent setup times, denoted by SDST flow shop. The first is related to the asymmetric traveling salesman problem (ATSP) polytope. The second is less common and is derived from a model proposed by Srikar and Ghosh based on the linear ordering problem (LOP) polytope. The main contribution of this work is the proof that any facet-defining inequality (facet) of either of these polytopes (ATSP and LOP) induces a facet for the corresponding SDST flow shop polyhedron. The immediate benefit of this result is that all developments to date on facets and valid inequalities for both the ATSP and the LOP can be applied directly to the machine scheduling polytope. In addition, valid mixed-integer inequalities based on variable upper-bound flow inequalities for either model are developed as well. The derived cuts are evaluated within a branch-and-cut framework.     

都市旅游：后奥运北京旅游产业的突破点

都市旅游是中国旅游发展的新潮流,是大城市发展到成熟和高水准阶段的产物。本文在对北京都市旅游发展潜力、发展现状进行分析的基础上,提出了今后北京都市旅游创新开发思路,就北京都市旅游产品整合开发策略进行了探讨。     

查慎行粤游诗的生态美

查慎行晚年游岭南,有诗《粤游集》二卷,查慎行的粤游诗体现了人与自然、人与人、人与社会、身与心、言与行、情与理的全面的生态和谐意识,对自然的诗意化观照和体验,对生命的认同和热爱,对社会和谐的追求和向往,对人生和现实的超越,是查慎行粤游诗最富有生态美意蕴的内核。从生态美学视野解读查慎行的粤游诗,对于理解清初朱彝尊、王士祯等诸大家的游粤诗创作有一定的借鉴意义。     

A Hybrid Genetic—GRASP Algorithm Using Lagrangean Relaxation for the Traveling Salesman Problem

Hybridization techniques are very effective for the solution of combinatorial optimization problems. This paper presents a genetic algorithm based on Expanding Neighborhood Search technique (Marinakis, Migdalas, and Pardalos, Computational Optimization and Applications, 2004) for the solution of the traveling salesman problem: The initial population of the algorithm is created not entirely at random but rather using a modified version of the Greedy Randomized Adaptive Search Procedure. Farther more a stopping criterion based on Lagrangean Relaxation is proposed. The combination of these different techniques produces high quality solutions. The proposed algorithm was tested on numerous benchmark problems from TSPLIB with very satisfactory results. Comparisons with the algorithms of the DIMACS Implementation Challenge are also presented.     

毫米波行波管电子光学系统计算机模拟

分析了毫米波行波管电子光学系统的基本特征和设计方法。提出了建立一体化电子光学模型,通过PIC模拟研究电子注静态传输特性的方法。对于改进和优化行波管电子光学系统设计,实现“设计制管一次成功”具有一定的参考价值。