浅议经评审的最低评标价法

经评审的最低评标价法是国际上普遍认可和通行的建筑工程招标方法。它有利于提高施工企业生产经营管理水平,节能降耗,向管理要效益,提高市场竞争力,最终促进施工企业生产力发展。就低价竞标的优点、存在问题及完善措施的具体做法做了叙述和探讨。     

发展农村物流业是推进新农村建设的重要途径

经实际调查了解了农村物流情况,并分析了农村物流问题,针对性提出了发展农村物流业的对策。     

运城地区高速公路服务设施冬季采暖环境问题分析及对策

通过调查对运城地区高速公路服务设施冬季采暖存在的环境问题进行分析,结合国家节能减排要求,提出了利用地源热泵清洁能源代替燃煤锅炉的对策措施,并从技术、经济和环境方面分析了地源热泵技术应用的可行性。     

一种改进蚁群优化算法的仿真研究

针对蚁群优化算法存在容易陷入局部最优、收敛速度慢、参数设置复杂等缺点,提出了一种改进的蚁群优化算法,研究了伪随机比例转移规则中参数 的取值方法,并对信息素的取值方式和信息素的更新规则进行了改进。最后以中国31个城市的旅行商问题和路径规划问题为实例,分别运用改进前后的蚁群算法进行了仿真研究。仿真结果表明：改进之后的算法不仅能够得到更好的解,更能显著地提高算法的收敛速度。     

有限经济批量和排序问题的模拟退火搜索算法

采用模拟退火算法,解决一个简单供应链中经济批量和排序问题。在这个供应链中,单一的一个生产系统要生产多种产品来满足装配系统的需求,假定参数、产品的需求率、生产率、整备时间和费用都是给定的常数。目标是求解最优的生产批量和排序,使得整个供应链中单位时间的库存、运输的总费用最小。     

基于环境协调理念的公路设计研究

在公路工程正式动工之前,设计单位要根据所收集的数据信息进行方案设计,为后期的施工作业提供合理的指导策略。针对近年来我国公路建设重心向山区转移的特点,以具体的工程案例为指导,采用环境协调理念对山区公路设计的新策略加以分析,为公路设计提供新的思路。     

集装箱港口船舶配载计划研究综述

梳理了集装箱港口船舶配载计划问题的国内外文献,从配载计划的分类、影响因素与求解方法三方面回顾了其研究现状和成果,探讨了目前研究中存在的不足与后续的研究方向。研究结果表明：在论文题目中直接点明主贝位规划问题或者箱位分配问题的文献越来越少,更多的是直接点明“配载计划问题”;多数文献考虑了船舶稳性、船舶强度、集装箱属性(尺寸、质量、类型等)、岸桥属性等影响配载计划问题中的几个因素,只有极少数文献将配载计划问题的影响因素全部考虑在内,因此,为了使研究更贴近港口实际操作,综合考虑配载计划问题的影响因素将成为未来的研究重点;配载计划还受到港口内其他作业的影响,因此,为了提高港口的作业效率和运营水平,应综合考虑集装箱港口各个区域之间的相互作用;随着铁水联运的发展,铁路集装箱也会堆放在船舶上,因而在配载计划问题中也需要考虑铁路集装箱的影响;多数文献都设计了智能算法,并获得了较多的优化解,但是为了更加直观形象地展示求解结果,应该将仿真优化与算法计算结合在一起。     

Two Bandwidth Packing Algorithms for the Centralized Wireless Network and Their Average-case Analysis

This paper presents a detail analysis of two bandwidth packing algorithms, used for processing connection requests in the centralized wireless network. Each call comes with a specific bandwidth request. A request can be satisfied only if there is sufficient bandwidth available during resource scheduling and allocation. Unsatisfied requests were held in a queue. The metric of bandwidth utilization ratio was used to quantify the performance of our algorithms. By theoretical analysis, our algorithms can improve the average bandwidth usage ratio significantly, about 8%~10% without adding much computation complexity. Moreover, our algorithms outperform next fit with fragmentation (NFF) algorithm when the bandwidth resource is scarce. In this paper, the contributions follows: Introducing bandwidth packing problem into wireless network; Proposing two new bandwidth packing algorithms for wireless network where the complicate scheduling algorithms are prohibited; Studying the average performance of our algorithms mathematically, which agree well with the simulation results.     

Regularization Method to the Parameter Identification of Interfacial Heat Transfer Coefficient and Properties during Casting Solidification

The accurate material physical properties, initial and boundary conditions are indispensable to the numerical simulation in the casting process, and they are related to the simulation accuracy directly. The inverse heat conduction method can be used to identify the mentioned above parameters based on the temperature measurement data. This paper presented a new inverse method according to Tikhonov regularization theory. A regularization functional was established and the regularization parameter was deduced, the Newton-Raphson iteration method was used to solve the equations. One detailed case was solved to identify the thermal conductivity and specific heat of sand mold and interfacial heat transfer coefficient (IHTC) at the meantime. This indicates that the regularization method is very efficient in decreasing the sensitivity to the temperature measurement data, overcoming the ill-posedness of the inverse heat conduction problem (IHCP) and improving the stability and accuracy of the results. As a general inverse method, it can be used to identify not only the material physical properties but also the initial and boundary conditions' parameters.     

基于MapBasic的战时运输最优路径问题研究

战时运输最优路径问题是一个多目标多约束随机动态路网寻优问题。在分析战时运输最优路径问题特性前提下,着重研究战时运输路阻函数模型,求出时间阻抗、风险阻抗和费用阻抗,标定阻抗参数μ1,μ2和μ3,及确定函数模型的MapBasic表达,在给出最优路径模型基础上,利用改进的Dijkstra算法求解。实例验证表明研究成果满足实用要求。