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   417篇
  免费   28篇
  国内免费   2篇
财政金融   13篇
工业经济   36篇
计划管理   194篇
经济学   23篇
综合类   32篇
运输经济   27篇
旅游经济   5篇
贸易经济   78篇
农业经济   3篇
经济概况   36篇
  2024年   2篇
  2023年   21篇
  2022年   8篇
  2021年   11篇
  2020年   19篇
  2019年   12篇
  2018年   6篇
  2017年   8篇
  2016年   5篇
  2015年   18篇
  2014年   40篇
  2013年   19篇
  2012年   42篇
  2011年   52篇
  2010年   36篇
  2009年   15篇
  2008年   25篇
  2007年   21篇
  2006年   15篇
  2005年   10篇
  2004年   18篇
  2003年   13篇
  2002年   9篇
  2001年   6篇
  2000年   2篇
  1999年   5篇
  1997年   3篇
  1996年   1篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
排序方式: 共有447条查询结果,搜索用时 906 毫秒
1.
介绍了一种新型的BCH码的译码方法,并给出了该译码算法的FPGA器件实现方法。与传统的译码算法相比,该算法具有译码速度快、硬件实现复杂度低等优点,从而使得该译码器具有速度快、体积小、性能稳定等特点。  相似文献   
2.
Chi-Yo  Joseph Z.  Gwo-Hshiung   《Technovation》2007,27(12):744-765
Since the year 2000, silicon intellectual property (SIP), which can minimize the gap in ‘design productivity’ that exists with systems-on-chip (SOC), has become one of the most important factors in the development of integrated circuit (IC) products in the SOC era. Although SIP is very important for IC industry development, complicated business, technical as well as legal issues inside SIP transactions have hindered successful transactions and the integration of SIPs into SOCs. Thus, web-based SIP e-Commerce mechanisms, called SIP Malls, have emerged, aiming to resolve complex SIP issues. To maintain its leading position and competitiveness in the World's IC industry, as well as the value added by SOC products in Taiwanese IC firms, the Taiwanese government has developed SIP Malls, using innovation policy tools. However, the Taiwanese SIP Mall industry remains immature. No existing Taiwanese SIP Malls generate a profit or account for a significant share of worldwide SIP transactions. This research will develop an analytical framework for defining an innovation policy portfolio that aims to develop Taiwan's SIP Mall industry, so that it will enhance the value added of SIP Malls and, thus, the nation's competitiveness in the SIP and IC industries, something which already has become one of the Taiwanese government's major concerns. The industry innovation requirements (IIRs) are summarized using the Delphi method. Meanwhile, the major IIRs identified by Decision Making Trial and Evaluation Laboratory (DEMATEL) are introduced. After the IIRs are derived, the relationships between the IIRs and innovation policy tools are derived by Grey relational analysis (GRA). Then, the innovation policy tools are clustered, based upon the Grey grades derived by GRA. Finally, reconfigured innovation policy portfolios are presented for the Taiwanese government's policy definition. The results demonstrate that developing an innovative policy portfolio that includes scientific, technical, educational, public enterprise, information, legal and regulatory, financial, and taxation policy tools will be the most necessary step towards developing Taiwan's SIP Mall industry.  相似文献   
3.
文章阐述了一种电话远程控制系统,并对其系统结构、各部分功能的实现和系统软件程序流程及主要软件功能进行了讨论,其摘机电路、挂机电路、密码电路简单实用;其受控对象如窗户状态、电器状态的反馈与控制电路稳定可靠。  相似文献   
4.
为提高彩电的安全性能,保护电路在大屏幕彩电中得到广泛应用。本文分析了康佳 T2988型画中画大屏幕彩电电源保护电路的保护模式和工作原理。  相似文献   
5.
文章介绍一种简单、实用、可靠的电机欠磁失磁检测电路及应用。在电气传动系统中该电路能有效地保证电机的安全运行。  相似文献   
6.
针对并行口设备开发的趋势及特点 ,详细介绍了 EPP协议的产生、特点及时序 ;并结合科研项目“ES2 42 0地震仪改造”提出了用 EPP协议仿 Intel 80 86系统接口的详细设计方案 ,该接口由读写逻辑生成电路、地址锁存器及译码器、仿 Intel 80 86总线及一些逻辑延时电路组成。并给出了电路框图及 Windows3 .x/95/98编程。经扩展后总线的双向通信速度为 850 KB/s与 ISA总线的速度相当。  相似文献   
7.
One of the main collective contributions of the various heterodox schools of monetary thought, such as circuit theory, Post Keynesian theory, modern money theory (MMT) and others, has been to stress the importance of the endogeneity of money via bank credit creation. It is necessary to stress the notion of a collective contribution because of the various claims and counter-claims to academic priority made in the literature. The recent exchange between T.I. Palley and E. Tymoigne and L.R. Wray in this journal provides a clear example of this. This response examines the differences between these writers in some detail.  相似文献   
8.
针对多层微波集成电路设计的微带线层间互连问题,介绍了垂直通孔互连、垂直带条互连和层耦合过渡互连三种高性能的互连方法,并且采用三维电磁仿真软件HFSS对这三种互连结构进行了建模和仿真。仿真结果表明,垂直通孔互连和垂直带条互连在0.1~25 GHz的频宽范围内,回波损耗S11<-20 dB,插入损耗S21>-1 dB,互连性能优良,而层耦合过渡互连在20~68 GHz内回波损耗S11 <-20 dB,插入损耗S21>-1 dB,具有在毫米波频段实现互连的潜力。  相似文献   
9.
This paper investigates the high-speed broadband situation in the EU and its prospects. It uses a deployment model to estimate the investment required to meet the Digital Agenda for Europe (DAE) broadband targets set by the European Commission in its Europe 2020 strategy at different stages: as of 2016, after expected operators’ deployment, after public subsidies and leveraged investment, and as expected in 2020. The model uses data at the NUTS3 level, which is the most granular level that has data available on the status of broadband deployment, to arrive at a coherent and comparable framework. From the different perspectives on the investment to meet DAE targets, the paper concludes on the need for an appropriate combination of incumbent and alternative operators investments, public subsidies and leveraged investments, and new investments, both public and private and non-existing as of 2016, examining their feasibility and the impact of different regulatory, technical, and policy strategies.  相似文献   
10.
田辰洋 《价值工程》2015,(12):164-167
本文主要分析了高速铁路在不同的供电方式下,容易出现的问题及产生的影响,在此基础上提出了解决的措施和建议,希望通过相关的改进措施达到更好地保护铁路沿线人员和设备安全的目的。  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