首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   366篇
  免费   30篇
  国内免费   3篇
财政金融   61篇
工业经济   38篇
计划管理   92篇
经济学   54篇
综合类   26篇
运输经济   6篇
旅游经济   12篇
贸易经济   71篇
农业经济   18篇
经济概况   21篇
  2024年   1篇
  2023年   6篇
  2022年   6篇
  2021年   6篇
  2020年   11篇
  2019年   19篇
  2018年   21篇
  2017年   13篇
  2016年   9篇
  2015年   14篇
  2014年   16篇
  2013年   38篇
  2012年   18篇
  2011年   28篇
  2010年   27篇
  2009年   19篇
  2008年   15篇
  2007年   16篇
  2006年   21篇
  2005年   22篇
  2004年   15篇
  2003年   2篇
  2002年   6篇
  2001年   9篇
  2000年   9篇
  1999年   6篇
  1998年   4篇
  1997年   3篇
  1996年   4篇
  1995年   3篇
  1994年   2篇
  1993年   2篇
  1991年   3篇
  1990年   1篇
  1989年   2篇
  1987年   2篇
排序方式: 共有399条查询结果,搜索用时 15 毫秒
91.
针对机载综合射频传感器系统高度综合化的实际需求,基于部分可重构技术提出了一种机载传感器功能波形重构设计方法,以实现在现场可编程门阵列(Field Programmable Gate Array,FPGA)芯片局部区域上时分复用机载功能波形。该方法引入一种便于功能波形移植部署的FPGA平台设计,并在此平台上完成机载功能波形在FPGA芯片局部区域的可重构具体设计。工程应用表明,该设计能够灵活有效复用可编程逻辑器件资源,提高了综合射频传感器系统的功能波形集成度,具有较好的实践意义。  相似文献   
92.
When the UK leaves the EU, trade arrangements between the UK and EU will change. Most of the options for future UK‐EU relationships currently under discussion imply increased trade barriers, which will reduce trade and also have effects on output and prices. In this paper, we use a multi‐market partial equilibrium model to analyse the vulnerability of 122 manufacturing industries to Brexit. In all five Brexit scenarios we model, there is an overall reduction in UK manufacturing output. Output grows in some industries but at the expense of higher consumer and intermediate goods prices. High tech and medium–high tech sectors are more at risk of a decline in domestic production than lower tech sectors. In most areas of the country, demand for high‐skilled workers falls more than for medium and low‐skilled workers.  相似文献   
93.
This paper considers a non‐Markov control problem arising in a financial market where asset returns depend on hidden factors. The problem is non‐Markov because nonlinear filtering is required to make inference on these factors, and hence the associated dynamic program effectively takes the filtering distribution as one of its state variables. This is of significant difficulty because the filtering distribution is a stochastic probability measure of infinite dimension, and therefore the dynamic program has a state that cannot be differentiated in the traditional sense. This lack of differentiability means that the problem cannot be solved using a Hamilton–Jacobi–Bellman equation. This paper will show how the problem can be analyzed and solved using backward stochastic differential equations, with a key tool being the problem's dual formulation.  相似文献   
94.
赵晓晶  刘肖云 《价值工程》2011,30(20):184-185
利用锥理论和非对称迭代方法,讨论了一类非单调二元算子方程解的存在唯一性,给出了迭代序列收敛于解的误差估计,所得结果是某些已知结果的改进和推广。  相似文献   
95.
本文从企业并购的信息角度入手,采用事件研究方法,考察了我国大宗股权协议转让过程中,相关公司的地理位置相近性对大宗股权协议转让公告效应的影响。论证了大宗股权收购的收购方对于同城的目标公司有强烈的偏好;同城收购的目标公司相对于异城收购的目标公司,可以在首次公告日的事件窗内取得统计上显著更高的异常收益;并且当目标公司规模小、风险大、高管持股比例高、收购方在收购后成为第一大股东、财务杠杆高等情况出现时,异常收益会更加显著。  相似文献   
96.
This paper derives a sufficient and necessary condition for arbitrage-free pricing, by the mathematical definition of linear dependency. It states that any pricing function that can be expressed as a linear combination of some of its partial derivatives inherently possesses the arbitrage-free property. This condition can serve as a quick ‘reality check’ to help search for arbitrage-free asset pricing.  相似文献   
97.
孔祥凤 《价值工程》2011,30(10):236-236
本文对二元函数可微性及高阶混合偏导数与求导次序无关的充分条件进行了推广并加以证明.  相似文献   
98.
Research has shown consumers either form inferences to fill in missing information or adapt processing to accommodate missing values. This article illustrates that processing may influence which attributes are deemed necessary for the choice task and consequently inferred and that attribute-based processing,leads to inference use. The article also tests a framework that incorporates missing information, processing, inference use, and evaluation variables into a single parsimonious model that shows (1) the effects of missing information on processing and inference use and (2) the effects of inference use on evaluations. The model incorporates a link between processing and inference use that may help explain mixed results regarding the degree and direction of impact of missing information on evaluations. Finally, it explores other variables such as missing information overlap, product familiarity and importance, and attribute type that may also influence inference use.  相似文献   
99.
偏最小二乘神经网络在建筑造价预测中的应用   总被引:1,自引:0,他引:1  
偏最小二乘回归方法在提取主成分方面具有很好的解释性,而且可以避免因素之间的多重相关性,提取的成分作为输入变量再用神经网络进行预测仿真,影响因素考虑周全,不用计算工程量,计算速度快,克服了普通神经网络运算量大,样本有限情况下易出现问题的弊端。  相似文献   
100.
Considering a positive portfolio diffusion X with negative drift, we investigate optimal stopping problems of the form where f is a nonincreasing function, τ is the next random time where the portfolio X crosses zero and θ is any stopping time smaller than τ. Hereby, our motivation is the obtention of an optimal selling strategy minimizing the relative distance between the liquidation value of the portfolio and its highest possible value before it reaches zero. This paper unifies optimal selling rules observed for the quadratic absolute distance criteria in this stationary framework with bang–bang type ones observed for monetary invariant criteria but in finite horizon. More precisely, we provide a verification result for the general stopping problem of interest and derive the exact solution for two classical criteria f of the literature. For the power utility criterion with , instantaneous selling is always optimal, which is consistent with previous observations for the Black‐Scholes model in finite observation. On the contrary, for a relative quadratic error criterion, , selling is optimal as soon as the process X crosses a specified function φ of its running maximum . These results reinforce the idea that optimal stopping problems of similar type lead easily to selling rules of very different nature. Nevertheless, our numerical experiments suggest that the practical optimal selling rule for the relative quadratic error criterion is in fact very close to immediate selling.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号