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51.
在建筑业高速发展的同时,高层建筑也迅速崛起。然而对于高危行业的建筑业,整个生命周期过程中都存在着很多的风险。因为在高层的施工中存在作业面较高,所用的机械设备和安全设施更多,作业周期更长等未知情况。文章中经研究分析确定了影响高层建筑施工安全的重要因素,通过对因素的分析划分构造指标体系,再利用层次分析法对各指标进行权重的确定,最后利用模糊数学原理对它进行评价。结合施工企业实例,利用综合评价模型得出了影响该企业安全施工的重要因素,提供了改进的方向和建议。  相似文献   
52.
This study analysed motorcycle crashes in Spain. Ninety-nine thousand three hundred and four motorcycle crash reports filed in the years 2006–2011 were extracted from the Directorate General of Traffic database of crashes with victims. These data were analysed in terms of gender, age groups, trip purpose, type of crash, speed violation, day of the week, harm caused, use of helmet and psychophysical conditions of the driver to study the characteristics of motorcycle crashes in Spain and to assess the differences between male and female motorcycle drivers in these crashes. Significant differences were found in all the variables considered in the study, which implies gender differences in the profile of the injured motorcycle driver. The severity of motorcycle crashes suffered by male drivers is higher than that of women. These results corroborate the need to develop measures differentiated by gender, based on their profile.  相似文献   
53.
在复杂电磁环境下,由于民航地空通信大频偏的要求,滤波器无法滤除波道内的干扰。针对此问题,提出了一种自适应抗干扰系统设计方法。对于落在波道内且与地空通信信号有效频带不重叠的干扰,首先对通信信号进行载波频率估计,然后使用自适应滤波方法进行干扰抑制;对于落在波道内且与地空通信信号有效频带重叠的恒包络干扰,首先重构载波信号,消除对恒包络信号估计的影响,然后根据恒包络信号的特性重构干扰信号并进行干扰分离。实验结果表明,该系统设计方法在不改变民航地空通信架构的前提下,抗有效频带外干扰的能力最大可以提升23.8 dB,抗恒包络干扰的能力最大可以提升39.4 dB,从而可以大幅提高航空飞行安全水平。  相似文献   
54.
目的了解某院药品不良反应(ADR)的发生特点及规律,为临床安全用药提供参考。方法对合肥市第二人民医院2016年至2018年上报的ADR报告进行回顾性分析。结果1864例ADR中,66~89岁患者所占比例最高(768例,占41.20%);女性患者984例,略多于男性(880例);静脉给药引发的ADR最多,占81.33%;发生ADR的药品主要为抗菌药品,其次为抗肿瘤药和中药制剂;ADR主要累及消化系统、皮肤及附件;ADR类型主要为一般ADR,导致严重的ADR主要是抗肿瘤药;ADR转归情况以痊愈和好转为主,两者占94.31%。结论老年患者更易发生ADR;抗菌药、抗肿瘤药等ADR发生率较高;所有剂型中注射剂型ADR发生率最高;消化系统、皮肤及附件损害最为常见。  相似文献   
55.
运用运筹学方法和理论,建立我国滨海旅游业的可拓物元模型,对2011-2015年滨海旅游业的安全度做出评价。结果表明,2011年我国滨海旅游业处于较安全状态,2012年其安全状态处于临界安全,2014年安全状态处于安全。5年来产业安全整体水平平稳提升,目前滨海旅游业产业安全处于较安全级别,系统比较稳定。建议从政府部门加大扶持力度、构建常态化旅游服务保障机制,重视文化内涵、深挖传统文化资源,树立以游客为本的理念,切实提高滨海旅游服务质量等几个维度,提升我国滨海旅游业的安全水平。  相似文献   
56.
Abstract

Accident risk analysis for human safety and infrastructural improvement are key requirements of the engineering sector. The purpose of this paper is to identify and prioritize problematic segments of roads based upon the risk evaluation concept and to focus on the severity of accidents regarding human life loss and easy manoeuvring. This study includes the concept of considering road segments as decision-making units for application of data envelopment analysis (DEA) technique which has no compulsion of the distribution function and critical assumptions, unlike the multiple regression models. According to the proposed methodology, a section of Motorway (M-2) Lahore-Islamabad has been analyzed. Out of 200 segments under consideration, 99 segments were selected with at least one accident and one injury or fatality. Furthermore, for risk calculation and ranking of road segments, the DEA technique along with the cross-risk matrix method was applied. This optimization technique could not only be helpful in ranking but also technical decision-making and prioritizations for safety improvement, policymaking and budget allocation.  相似文献   
57.
Food safety systems in emerging markets are currently facing a transformation period, becoming more stringent because of an increasing demand for safer food. Consequently, policy makers need to find strategies to increase food safety while giving the industry time to improve their performance. In Thailand, policy makers have adopted the strategy of upgrading food safety standards gradually. Government and private food safety brands and labels were introduced onto the market but little is known whether Thai consumers have preferences for them or not. This study is aimed at evaluating Thai consumers’ preferences for food safety labels and brands on fresh produce, using a surveyed based on discrete-choice experiments. A sample of 350 Thai consumers was surveyed in Bangkok and Nonthaburi in 2013. Quota sampling according to the shopping outlets and convenience sampling methods were adopted. Two hundred respondents were recruited at fresh-food markets and 150 respondents were recruited at supermarkets. We found that consumers are willing-to-pay more for both government led food safety label and private brands, but that there is high heterogeneity in their preferences. The high degree of social desirability for food safety labels confirms that food safety labelling policy should be supported. However, the provision of information and credibility are vital in order to mitigate the risk of consumer deception by self-claimed labels.  相似文献   
58.
《Journal of Retailing》2015,91(3):533-542
Retailers recently became required to provide specific country-of-origin information for muscle cuts of beef, chicken, pork, lamb, and goat. Drawing from the consumer inference and activation theory literatures, hypotheses are offered regarding how consumers use country-of-origin labeling (COOL) to draw inferences related to specific product attributes and how these inferences, in turn, lead to differences in mediation effects for purchase intentions. Results from a pilot study and two experiments reveal that consumers are more likely to purchase meat when it is identified as a U.S. product. Furthermore, the relative strength of the mediating effects of perceived food safety, taste, and freshness differs as expected. The authors show how the direct and indirect effects of the country-of-origin disclosure are attenuated by the presentation of objective information about the meat processing systems of competing countries. Given the recently mandated COOL disclosures, results have important implications for food retailers, members of the supply chain, and consumers.  相似文献   
59.
This study evaluated the effectiveness of red-light cameras in Dammam, the Kingdom of Saudi Arabia. Two methods were used to assess changes in crash risk at the intersections at which the red-light camera programme had been operating. Geospatial analysis was used to visualize trends in road crash density over the geographical region of Dammam and a pre--post-camera crash analysis was undertaken. The distribution of injury crashes was greater than that of crashes which included property damage, the latter of which was concentrated around central Dammam. The five red-light cameras installed in 2012 were located outside areas of high-crash and injury density, and the total number of crashes reported in the three-month periods after installation was double that before the cameras were installed. This increase in the number of crashes also occurred at the five comparison sites (without red-light cameras), indicating a null effect. The findings from this study are contrary to previous evaluations of speed management programmes associated with red-light cameras. The study highlights the challenges in obtaining data for such research and illustrates that a reliance on overt, fixed camera's to manage speed is unlikely to deliver significant reductions in road trauma.  相似文献   
60.
This study examines health inspection data from casual dining restaurants and compares differences of food code violations between ethnic and nonethnic restaurants. A total of 7,415 violations were retrieved from the restaurant inspection reports of 769 restaurants. Ethnic restaurants have more violations than nonethnic restaurant in categories related to food time/temperature violations, cross contamination, and food condition/surface/labels. Nonethnic and chain restaurants had fewer behavioral violations than ethnic and independently operated restaurants. Ethnic restaurants were 1.74 times more likely than nonethnic restaurants to have critical violations. Meanwhile, independent restaurants were 1.64 times more likely than chain restaurants to have critical violations.  相似文献   
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