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   781篇
  免费   34篇
  国内免费   15篇
财政金融   74篇
工业经济   46篇
计划管理   171篇
经济学   114篇
综合类   160篇
运输经济   4篇
旅游经济   4篇
贸易经济   97篇
农业经济   59篇
经济概况   101篇
  2024年   2篇
  2023年   5篇
  2022年   7篇
  2021年   21篇
  2020年   22篇
  2019年   10篇
  2018年   10篇
  2017年   17篇
  2016年   14篇
  2015年   24篇
  2014年   61篇
  2013年   50篇
  2012年   67篇
  2011年   79篇
  2010年   64篇
  2009年   40篇
  2008年   53篇
  2007年   69篇
  2006年   63篇
  2005年   52篇
  2004年   21篇
  2003年   20篇
  2002年   20篇
  2001年   13篇
  2000年   10篇
  1999年   3篇
  1998年   1篇
  1997年   2篇
  1996年   3篇
  1995年   2篇
  1994年   3篇
  1993年   1篇
  1991年   1篇
排序方式: 共有830条查询结果,搜索用时 15 毫秒
81.
Huge trade surplus attracks more and more attention to the China's economy operation, a controversial topic on people's lips as well.  相似文献   
82.
运用期权博弈方法,从无政府担保基本情形出发,构建 PPP 项目特许权期决策模型,考量政府参与风险分担对特许权期的影响。结果表明,收益波动率一定的情况下,特许权期随着政府最低收益担保期望价值的增加而减少;而在政府最低收益担保期望价值一定的情况下,特许权期随着收益波动率的增加而增加。鉴此,政府应根据项目的风险收益情况实施弹性特许权期制。  相似文献   
83.
对转型期中国劳动关系影响的分析   总被引:1,自引:0,他引:1  
对于转型期中国劳动关系影响的分析,学术界目前大多是从劳动关系内外部因素影响的角度采加以研究的,但却忽视了处于转型期的中国劳动关系对以上诸因素的反作用分析。转型期的中国劳动关系对劳动关系内部构成因素即企业、劳动者和政府有重大影响。  相似文献   
84.
DZ-1A重整预加氢催化剂的长周期工业应用   总被引:1,自引:0,他引:1  
DZ-1A催化剂开车一次成功,8个月以后进行了标定,结果表明,该催化剂的加氢油各项指标达到了重整原料油要求.现在已经连续运转5α.该催化剂是一种性能优良、寿命较长的催化剂.  相似文献   
85.
近年来,随着极端暴雨事件的出现,导致城市内涝灾害频繁发生,原有降雨历时仅为2h的市政排水设计暴雨强度公式已无法满足城市暴雨设计的需求,因此就要延长暴雨采样历时,推求出长历时(24h)暴雨强度公式。针对以上问题,根据北京市提供的52a(1961-2012)原始降雨资料并进行数字化处理,结合水利的长历时特点,采用兼顾市政排水,水利排涝,内涝防治的采样方法,应用P-Ⅲ分布曲线进行频率分析后采用6种经典方法推求暴雨强度公式的参数值,优选出误差最小且满足规范要求的暴雨强度公式参数值,进而推求长历时暴雨强度公式,在此基础上与短历时暴雨强度公式比较,分析两者的差异,为城市雨水排除规划设计提供科学依据和参考。  相似文献   
86.
为满足实际雷达系统对高精度和高实时性的要求,提出了一种改进的“当前”统计模型变采样率机动目标跟踪算法。该算法针对“当前”统计模型必须预设加速度极值和机动频率的问题,提出一种加速度方差和机动频率在线同步自适应方法,建立改进的“当前”统计模型机动目标跟踪算法;针对在线自适应方法计算量大的问题,结合采样周期的大小与目标机动特性的关系,引入变采样率方法。仿真结果表明,与传统“当前”统计模型相比,改进的“当前”统计模型机动目标跟踪算法能显著提高对不同机动强度目标的跟踪精度;变采样率方法通过减少采样点数,节省了系统资源,提高了跟踪实时性;所提算法将两者结合,用传统的“当前”统计模型1.5~2倍的平均采样周期得到了更小的位置均方根误差,实现了用单模型方法同时改善跟踪精度和实时性的目的。  相似文献   
87.
We examine the relationship between restatements of prior period financial results and firm value in China. This relationship is relevant to the millions of global investors who purchase Chinese equity securities because Chinese regulatory authorities must focus on the restatement events that, in their judgment, most warrant investigation. We recommend that they focus their attention on restatement announcements (and the firms that announce them) that possess the characteristics that most impact firm value.Prior studies of the American equity markets found evidence of a relationship between the nature of the restatement announcements and firm value, as well as evidence that core account adjustments and high-magnitude adjustments affect firm value more than noncore account adjustments and low-magnitude adjustments. However, based on a sample of Chinese listed firms that made corporate announcements that appeared in the Asian press between 2003 and 2011, we only find mixed evidence in the Chinese equity markets in support of the former relationship, and no evidence at all in support of the latter relationship.In other words, restatement announcements in China do not impact firm value to the same extent, and in the same manner, as restatement announcements in America. Chinese regulators must thus develop policies that are unique to the Chinese markets in order to effectively prioritize their oversight activities on firms that issue restatement announcements.What factors should be considered by Chinese regulators? We identify a collection of corporate governance variables, as well as a smaller collection of financial variables, that are significantly associated with decreases in firm value. We also develop a set of regression analyses that utilize these variables to explain a significant portion of the variability of firm value during the sample period. Interestingly, however, we find no evidence that the growth patterns of the firms are significantly associated with changes in firm value.Using this evidence, we recommend the development of a model of regulatory guidance that is customized for the unique characteristics of the Chinese equity markets. We believe that this model can help Chinese authorities focus their attention on specific restatement announcements that most impact firm value.  相似文献   
88.
方方的《乌泥胡年谱》通过不同的视角刻画了特定时代特定政治背景下知识分子的艰难行走。他视角是广角镜头,照出了知识分子的悲剧群像,内心独白是个体心态及命运写照,看出了知识分子人格萎缩的渐变过程,"我"视角浓缩了宏大的时空,将过去与未来衔接在一起,给读者深层的启发与感悟。  相似文献   
89.
徐福生 《价值工程》2013,(21):51-52
随着我国经济的迅猛发展,铁路客运出现了越来越多的客流高峰期。文章探讨在既有设施设备条件约束下,需要采用特殊运输组织方法解决客流高峰期问题。分析了客流高峰期的组成结构及行程原因后,提出了应对高峰期客流的运输组织策略。  相似文献   
90.
Rental markets for cultivated land and agricultural investments in China   总被引:1,自引:0,他引:1  
The purpose of this paper is to empirically track the progress and consequences of the emergence of cultivated land markets in China since 2000. We draw on a set of nationwide, household‐level panel data (for 2000 and 2008) and find that the markets for cultivated land rental have emerged robustly. According to our data, 19 of China's cultivated land was rented in farm operators in 2008. We also find that the nature of China's cultivated land rental contracts has become more formal and lengthened the period of time that the tenant is able to cultivate the rented‐in plots. While there may be benefits for lessors and tenants, our data show that there are falling rates of investment in organic manure. The farmers in our sample have reduced organic manure use from 13 tons/ha in 2000 to 5 tons/ha in 2008. Part of this fall is due to the rise of cultivated land rental markets. The analysis, however, does not find that improved property rights in cultivated land rental affect investment largely because property rights have largely been established by 2000, the first year of our sample. Our results, however, also show that there are forces that appear to be mitigating the negative consequences of rising cultivated land rental. After holding constant initial rental rates and other factors, we find that the gap between investment in organic manure in own land and rented‐in land is narrowing. One interpretation of our findings is that if policymakers can find ways to even further strengthen the rights of lessors and tenants as well as lengthen contract periods, farmers—even those that rent—will invest more in their land, because they will be able to capture the returns to their investments.  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