全文获取类型
收费全文 | 222篇 |
免费 | 18篇 |
专业分类
财政金融 | 6篇 |
工业经济 | 72篇 |
计划管理 | 101篇 |
经济学 | 3篇 |
综合类 | 15篇 |
贸易经济 | 17篇 |
农业经济 | 8篇 |
经济概况 | 18篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 9篇 |
2014年 | 25篇 |
2013年 | 26篇 |
2012年 | 19篇 |
2011年 | 26篇 |
2010年 | 28篇 |
2009年 | 12篇 |
2008年 | 15篇 |
2007年 | 11篇 |
2006年 | 14篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 7篇 |
2002年 | 1篇 |
2001年 | 2篇 |
1999年 | 4篇 |
1997年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有240条查询结果,搜索用时 128 毫秒
1.
Understanding the exploration–exploitation dilemma: An fMRI study of attention control and decision‐making performance 下载免费PDF全文
This paper studies the cognitive processes that enable decision makers to switch between exploitation and exploration. We use functional magnetic resonance imaging (fMRI) in a sample of expert decision makers to make two main contributions. First, we identify and contrast the specific brain regions and cognitive processes associated with exploitation and exploration decisions. Exploitation activates regions associated with reward seeking, which track and evaluate the value of current choices, while exploration relies on regions associated with attentional control, tracking the value of alternative choices. Second, we propose and test the idea that stronger activation of the brain circuits related to attentional control allows individuals to achieve better decision‐making performance as a result. We discuss the implications of these results for strategic management research and practice. Copyright © 2013 John Wiley & Sons, Ltd 相似文献
2.
冻结造孔施工过程中,控制井斜靶域半径问题是冻结造孔的关键点。以陕西麟北煤业开发有限责任公司园子沟煤矿冻结造孔施工为例,本文着重分析冻结造孔施工中靶域半径控制及钻孔防斜保直、测斜、定向技术实践应用。 相似文献
3.
通过改变搅拌桨形状,对8立方液固两相体系的羧化釜进行了搅拌流场、固含率进行模拟,从流体力学角度对羧化釜进行了优化。将模拟优化结果用于实际工业生产中,结果表明:计算流体力学(CFD)模拟优化后的羧化釜能够改善釜内流体流动情况,从而对反应产生影响,使原料转化率提高了5.6个百分点。 相似文献
4.
5.
We consider a framework for solving optimal liquidation problems in limit order books. In particular, order arrivals are modeled as a point process whose intensity depends on the liquidation price. We set up a stochastic control problem in which the goal is to maximize the expected revenue from liquidating the entire position held. We solve this optimal liquidation problem for power‐law and exponential‐decay order book models explicitly and discuss several extensions. We also consider the continuous selling (or fluid) limit when the trading units are ever smaller and the intensity is ever larger. This limit provides an analytical approximation to the value function and the optimal solution. Using techniques from viscosity solutions we show that the discrete state problem and its optimal solution converge to the corresponding quantities in the continuous selling limit uniformly on compacts. 相似文献
6.
目的:探讨限制性液体复苏治疗创伤性失血性休克的疗效及对炎症因子的影响。方法:选择2008年3月至2011年3月60例创伤性失血性休克患者,随机分为对照组和观察组,每组30例。对照组采用充分液体复苏治疗,观察组应用限制性液体复苏治疗,观察两组患者的术前输液量、红细胞压积、凝血酶原时间、死亡率以及C-反应蛋白、IL-6浓度变化。结果:观察组术前输液量、凝血酶原时间、死亡率、C-反应蛋白、IL-6浓度分别是(1768.79±236.54)ml、(12.14±4.13)s、6.67%、(102.43±33.57)ng/L、(213.49±64.82)ng/L,明显低于对照组的(2876.59±287.34)ml、(17.13±3.94)s、16.67%、(124.67±37.84)ng/L、(275.61±72.35)ng/L,P<0.05。观察组术前红细胞压积是(31.45±3.25)%,显著高于对照组的(24.37±3.69)%,P<0.05。结论:限制性液体复苏治疗创伤性失血性休克临床疗效较好,减轻机体炎症反应,有利于患者康复。 相似文献
7.
张祥兆 《石油工业技术监督》2011,27(5):38-42
"测量不确定度"是当前国际上表示检测结果的通用做法,如何对测量结果的不确定度进行合理的评定,是一直以来困扰检测实验室的一个难题。依据测量不确定度的评价原则,首先通过对四苯硼钠、滴定度等一系列可能产生不确定度的分量进行计算,最后合成钾含量测定的不确定度。对钻井液用聚丙烯酰胺钾盐中钾含量测定的不确定度进行了评定,对钻井液化学剂的准确检测具有借鉴意义。 相似文献
8.
本文研究了影响蒸汽驱效果的主要因素,分析了油藏地质条件和蒸汽驱过程中的操作参数两方面因素对蒸汽驱效果的影响,总结出适合蒸汽驱的油藏地质条件和合理的蒸汽驱操作条件。 相似文献
9.
通过高精度磁测和幅频激电探测两种方法对松林坪硫铁矿区进行了实地探测,进而了解了该矿区硫铁矿的分布及储量,为今后在该矿区的进一步工作奠定了基础。 相似文献
10.
《Enterprise Information Systems》2013,7(2):246-278
Multi-disciplinary design optimisation (MDO) is one of critical methodologies to the implementation of enterprise systems (ES). MDO requiring the analysis of fluid dynamics raises a special challenge due to its extremely intensive computation. The rapid development of computational fluid dynamic (CFD) technique has caused a rise of its applications in various fields. Especially for the exterior designs of vehicles, CFD has become one of the three main design tools comparable to analytical approaches and wind tunnel experiments. CFD-based design optimisation is an effective way to achieve the desired performance under the given constraints. However, due to the complexity of CFD, integrating with CFD analysis in an intelligent optimisation algorithm is not straightforward. It is a challenge to solve a CFD-based design problem, which is usually with high dimensions, and multiple objectives and constraints. It is desirable to have an integrated architecture for CFD-based design optimisation. However, our review on existing works has found that very few researchers have studied on the assistive tools to facilitate CFD-based design optimisation. In the paper, a multi-layer architecture and a general procedure are proposed to integrate different CFD toolsets with intelligent optimisation algorithms, parallel computing technique and other techniques for efficient computation. In the proposed architecture, the integration is performed either at the code level or data level to fully utilise the capabilities of different assistive tools. Two intelligent algorithms are developed and embedded with parallel computing. These algorithms, together with the supportive architecture, lay a solid foundation for various applications of CFD-based design optimisation. To illustrate the effectiveness of the proposed architecture and algorithms, the case studies on aerodynamic shape design of a hypersonic cruising vehicle are provided, and the result has shown that the proposed architecture and developed algorithms have performed successfully and efficiently in dealing with the design optimisation with over 200 design variables. 相似文献