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排序方式: 共有350条查询结果,搜索用时 15 毫秒
1.
在多年来快速化、粗放型城镇化发展进程中,非集中建设区有关保护与发展、规划与建设、实施与管理等问题愈发突出,而我国空间规划与行政机构的变革为解决非集中建设区众多问题提供了时代契机。本文突破"城市非建设用地""非城市建设用地"概念的局限性,针对各市新一轮总体规划提出的"非集中建设区"进行概念内涵解析,剖析了非集中建设区规划管控现状问题,借鉴了西安、上海、台湾地区的实践经验,在统一规划体系建设的时代背景下,提出采取"多规合一"的全域空间规划模式,构建系统化、统一化规划编制与管控体系,以及通过功能主导的政策分区、"规土合一"的土地用途、"生态保护与建设控制"的双向指标等管控方式实现非集中建设区统一性规划、整体性治理的思路。  相似文献   
2.
为了能够在真实硬件平台上进行实现,本文对原有的误差校正构造性神经网络算法进行了优化,并对优化后的误差修正算法进行了FPGA设计与实现。提出算法通过在自动生成一个合适的神经架构的同时对二个参数进行设置来提高算法性能。本文对这种算法实现的所有步骤进行了全面的描述并利用两种基准问题对结果进行了深入分析。结果显示,与标准的基于个人计算机(PC)的实现相比,本文提出的神经网络算法FPGA实现在计算速度方面有着明显的提高,由此证明了FPGA在误差校正算法神经计算任务中的实用性及适用性。  相似文献   
3.
Energy-efficient scheduling is highly necessary for energy-intensive industries, such as glass, mould or chemical production. Inspired by a real-world glass-ceramics production process, this paper investigates a bi-criteria energy-efficient two-stage hybrid flow shop scheduling problem, in which parallel machines with eligibility are at stage 1 and a batch machine is at stage 2. The performance measures considered are makespan and total energy consumption. Time-of-use (TOU) electricity prices and different states of machines (working, idle and turnoff) are integrated. To tackle this problem, a mixed integer programming (MIP) is formulated, based on which an augmented ε-constraint (AUGMECON) method is adopted to obtain the exact Pareto front. A problem-tailored constructive heuristic method with local search strategy, a bi-objective tabu search algorithm and a bi-objective ant colony optimisation algorithm are developed to deal with medium- and large-scale problems. Extensive computational experiments are conducted, and a real-world case is solved. The results show effectiveness of the proposed methods, in particular the bi-objective tabu search.  相似文献   
4.
随着社会的发展,人居环境日新月异,景观设计专业顺理成章的成为各大院校的热门专业。但课程设置体系中存在着诸多问题。未能做到因材施教。本文针对艺术院校景观专业的现存问题,提出课程教学应着手于小尺度空间。以工作模型作为主要研究载体,渐进的培养掌生综合分析问题的能力,提高学生的空间感知,运用构成艺术语言转译空间精神,营造个性的艺术空间。  相似文献   
5.
采用SF-36生存质量量表对城郊煤矿井下掘进工作面的273名作业人员进行问卷调查,并采用回归分析确定其主要影响因素。分析结果表明,重测信度系数均大于0.7,显示重测信度较好;分半信度系数为0.7290.7,说明内部一致性分半信度较好;因子累积贡献为81.476%50%,体现此次量表调查具有良好的结构效度;Logistic回归分析发现年龄和工种是影响掘进工作面作业人员生存质量的主要因素,钻眼工和人力推车工是生存质量状况最差的工种。SF-36量表在煤矿井下掘进工作面作业人员生存质量调查中,显示出良好的信效度。  相似文献   
6.
防治水患是云冈石窟文物保护的重要措施,而水患的形成与石窟文物本身的建造特征具有很大的关系。云冈石窟依据古代风水理论进行选址规划,使其必然受到多种水源的侵袭。洞窟与入渗水、凝结水和地下水相互作用的特征取决于石窟的结构形式、规模、配套建筑物和石雕的造型工艺。采用修建窟檐和室内空气除湿的办法,可以提高窟内水汽环境的稳定性,减少凝结水和冻结过程产生的风化损害。  相似文献   
7.
The problem of assigning gates to arriving and departing flights is one of the most important problems in airport operations. We take into account the real multi-criteria nature of the problem by optimizing a total of nine gate allocation objectives that are oriented both on convenience for airport/airline services and passenger comfort. As far as we are aware, this is the largest number of objectives jointly optimized in the GAP literature. Given the complexity of the considered problem, we propose a heuristic approach based on the Breakout Local Search (BLS) framework. BLS is a recent variant of the Iterated Local Search (ILS) with a particular focus on the perturbation strategy. Based on some relevant information on search history, it tries to introduce an appropriate degree of diversification by determining adaptively the number and type of moves for the next perturbation phase. Moreover, we use a new memory-based greedy constructive heuristic to generate a starting point for BLS. Benchmark instances used for our experiments and comparisons are based on information provided by Manchester Airport.  相似文献   
8.
Assembly lines of big-size products such as buses, trucks and helicopters are very different from the lines studied in the literature. These products’ manufacturing processes have a lot of tasks most of which have long task times. Since traditional assembly line models including only one worker in each station (i.e. simple assembly lines) or at most two workers (two-sided assembly lines) may not be suitable for manufacturing these type of products, they need much larger shop floor for a number of stations and long product flow times. In this study, an assembly line balancing problem (ALBP) with parallel multi-manned stations is considered. Following the problem definition, a mixed integer programming formulation is developed. A detailed study of priority rules for simple ALBPs is also presented, and a new efficient constructive heuristic algorithm based on priority rules is proposed. In order to improve solutions found by the constructive heuristic, a genetic algorithm-based solution procedure is also presented. Benchmark instances in the literature are solved by using the proposed mathematical programming formulation. It has been seen that only some of the small-size instances can be solved optimally by this way. So the efficiency of the proposed heuristic method is verified in small-size instances whose optimal solutions are found. For medium- and big-size instances, heuristics’ results and CPU times are demonstrated. A comparative evaluation with a branch and bound algorithm that can be found in the literature is also carried out, and results are presented.  相似文献   
9.
超弹性体本构模型的理论和特种试验方法   总被引:2,自引:0,他引:2  
重点介绍了超弹性体本构模型的基本理论:常用应变能函数形式、应力表达方式、模型适用性。同时详细阐述了构建橡胶超弹性本构模型所需的3类特种测试:单轴拉伸、等双轴拉伸、纯剪切。明确了每种试验的试样制备方法、几何形状、试验条件、设备要求、数据处理方法,指出了利用试验数据建立超弹性本构模型以及非线性分析时的注意事项,对于提高橡胶类材料的有限元分析精度和结果可靠性有重要意义。  相似文献   
10.
General spousal perceived criticism (PC) robustly predicts psychological symptoms and is associated with marital discord (e.g., Hooley & Teasdale, 1989); however, it is unclear what types of criticism PC encompasses (Renshaw, 2008). One hundred eighteen couples rated general PC and both constructive and destructive criticism from their own videotaped spousal discussions. Independent judges also coded criticism from the discussions. Results suggest that destructive rather than constructive criticism is related to PC. That PC primarily reflects destructive criticism may explain its utility in predicting relapse. Future studies will benefit from separate application of constructive and destructive criticism measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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