全文获取类型
收费全文 | 270篇 |
免费 | 13篇 |
专业分类
财政金融 | 27篇 |
工业经济 | 16篇 |
计划管理 | 100篇 |
经济学 | 44篇 |
综合类 | 6篇 |
运输经济 | 37篇 |
旅游经济 | 5篇 |
贸易经济 | 29篇 |
农业经济 | 11篇 |
经济概况 | 8篇 |
出版年
2024年 | 2篇 |
2023年 | 7篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 17篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 20篇 |
2015年 | 17篇 |
2014年 | 15篇 |
2013年 | 15篇 |
2012年 | 15篇 |
2011年 | 24篇 |
2010年 | 7篇 |
2009年 | 20篇 |
2008年 | 17篇 |
2007年 | 20篇 |
2006年 | 13篇 |
2005年 | 11篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 7篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 6篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有283条查询结果,搜索用时 15 毫秒
121.
High multiplicity scheduling problems arise naturally in contemporary production settings where manufacturers combine economies of scale with high product variety. Despite their frequent occurrence in practice, the complexity of high multiplicity problems – as opposed to classical, single multiplicity problems – is in many cases not well understood. In this paper, we discuss various concepts and results that enable a better understanding of the nature and complexity of high multiplicity scheduling problems. The paper extends the framework presented in Brauner et al. [ Journal of Combinatorial Optimization (2005 ) Vol. 9, pp. 313–323] for single machine, non-preemptive high multiplicity scheduling problems, to more general classes of problems. 相似文献
122.
文章在建立配送车辆路径优化问题数学模型的基础上,构造了遗传算法来求解该问题,并在算法中引入了自然选择、交叉操作、变异操作等思想:实验结果表明,此算法可以有效求得车辆路径问题的优化解或近似优化解.是求解车辆路径问题的一个较好的方案。 相似文献
123.
124.
一种不确定环境下供应链的模型与算法 总被引:1,自引:0,他引:1
供应链管理作为一种新型的企业关系管理模式在现代市场竞争中为企业生存与发展提供了一种工具。本文针对不确定环境下供应链的优化进行了研究。给出了一个供应链的仿真模型及其优化算法。 相似文献
125.
Kelvin?BalcombeEmail author Alastair?Bailey Iain?Fraser 《Journal of Productivity Analysis》2005,24(1):49-72
In this paper we argue that the standard sequential reduction approach to modelling dynamic relationships may be sub-optimal when long lag lengths are required and especially when the intermediate lags may be less important. A flexible model search approach is adopted using the insights of Bayesian Model probabilities, and new information criteria based on forecasting performance. This approach is facilitated by exploiting Genetic Algorithms. Using data on U.K. and U.S. agriculture the bivariate time series relationship between R&D expenditure and productivity is analysed. Long lags are found in the relationship between R&D expenditures and productivity in the U.K. and in the U.S. which remain undiscovered when using the orthodox approach. This finding is of particular importance in the debate on the optimal level of public R&D funding.JEL Classification: C22, C51, Q16 相似文献
126.
127.
基于遗传算法的包装废弃物回收逆向供应链网络构建研究 总被引:1,自引:0,他引:1
随着人们对生态环保和经济可持续发展的进一步认识,面对可再利用包装废弃物资源的浪费和对环境造成的污染,越来越多的人们意识到包装废弃物回收的重要性。文章分析了国内包装废弃物回收的现状,提出了包装废弃物回收的逆向供应链网络模型,利用遗传算法,对模型进行了优化求解,并给出了算例。 相似文献
128.
为了提高仓储系统中物流分拣的效率,设计了一套基于多台自动导引运输车(AGV)的自动分拣系统。首先将整个系统分解为硬件部分和软件部分,硬件部分主要包含服务器、多台AGV和机械手等等,软件部分的设计主要包含智能调度算法设计、最短路径算法设计和多AGV之间的避障算法设计等等;之后,通过逐步完成上述子模块的设计工作,即可完成整个系统的设计。经过在工厂一段时间的试运行,实践结果表明,该套系统的设计能够完成多台AGV的调度,并较大地提高了物流分拣的效率。 相似文献
129.
One of the main challenges of retail units is to determine the order quantities of different types of products, each with a specific expiry date, so that the system cost including shortage cost is minimized. We study a new multi-product multi-period replenishment problem for a First Expired-First Out (FEFO) based warehouse management system. The proposed nonlinear model is first converted to a linear one and then solved by applying two evolutionary algorithms: the Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), in which design parameters are set using Taguchi method. Computational results demonstrate the applicability of the proposed model for perishable items and comparing the results shows the efficiency of the proposed metaheuristics as well. 相似文献
130.
Francisco J. Martínez-López Author Vitae Jorge Casillas Author Vitae 《Industrial Marketing Management》2009,38(7):714-731
In its introduction this paper discusses why marketing professionals do not make satisfactory use of the marketing models posed by academics in their studies. The main body of this research is characterised by the proposal of a brand new and complete methodology for knowledge discovery in databases (KDD), to be applied in marketing causal modelling and with utilities to be used as a marketing management decision support tool. Such methodology is based on Genetic Fuzzy Systems, a specific hybridization of artificial intelligence methods, highly suited to the research problem we face. The use of KDD methodologies based on intelligent systems like this can be considered as an avant-garde evolution, exponent nowadays of the so-called knowledge-based Marketing Management Support Systems; we name them as Marketing Intelligent Systems. The most important questions to the KDD process-i.e. pre-processing; machine learning and post-processing-are discussed in depth and solved. After its theoretical presentation, we empirically experiment with it, using a consumer behaviour model of reference. In this part of the paper, we try to offer an overall perspective of how it works. The valuation of its performance and utility is very positive. 相似文献