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41.
Food waste has drawn increasing public attention, and the high levels of estimated waste are largely considered to be a failure of our current food system. Recently, economists have begun to weigh in, showing food waste can emerge as the result of a complex equilibrium affected by consumers’ preferences for convenience; expectations about future food prices and availability; food safety concerns; producers’ costs of holding inventory, transportation, and storage; government regulation; and technology. If food waste is a form of inefficiency, there are either strong economic motivations to reduce waste, or unmeasured costs or preferences affecting waste decisions. If consumers have behavioral biases, suffer from information asymmetries, or do not pay the full cost of their waste, there may be a role for government intervention to reduce waste, but most empirical models in the literature have not articulated or quantified the extent of the deadweight loss from the market failures in relation to food waste. In some cases, waste reduction efforts could harm producers if overall demand for food is reduced or harm consumers if overconsumption is encouraged, quality or safety degrades, or supply disruptions occur. Technological innovations, which lower the cost of storage or extend shelf life have the potential to improve both consumer and producer welfare. 相似文献
42.
在多传感器水质数据融合领域,证据理论是有效的数据融合方法之一,但基本概率分配一般不易确定,从而使数据融合能力难以有效发挥。支持向量机是统计学习理论之上的高级分类算法,具有普适性和全局优化等特点,但输出的基本概率分配有待进一步提高。提出了一种基于证据理论和新型模糊支持向量机相结合的数据融合方法,通过建立基于分类超平面距离的模糊隶属度,训练模糊支持向量机提高传统支持向量机的基本概率分配,并结合证据理论进行海河水质数据融合。通过证据理论分别结合支持向量机和模糊综合评价法与上述方法进行对比实验,经精度、平均绝对百分误差、均方根误差等指标验证,精度提高10.5%,表明所提方法是一种可靠的多传感器的水质融合方法,较其他方法具有更高的融合精度。 相似文献
43.
China has been conducting massive land consolidation (LC) projects since the late 1990s to ensure national food security which has been one of the common issues in the world. How the implementation of LC projects affects grain production stability is a question should be answered. Basing on an empirical analysis at the county level in Hubei Province, China, this paper separates the trend component and the fluctuation component from a time series of grain production over 1991-2016 using the H-P filtering method. Then we estimate the impacts of LC projects and climate change on the trend and fluctuation rate of grain production for the entire Hubei Province. Moreover, the effects on the production of different major crops for the central, eastern, southwestern, northwestern and northern areas are also examined, respectively. The results show that: (1) the production trends for five subareas and the whole area all have followed a trajectory of “increase-decrease-increase” from 1991 to 2016. The magnitude of fluctuation rate was large but became smaller in recent years. (2) The contribution of LC to the long-term trends of grain production for the entire samples in Hubei Province mainly benefits from the growth in the cultivated land area through LC; more LC investment and newly-added arable land area promote the sudden increase in grain production above the long-term trends, while the impacts of LC area are negative. (3) The impacts of LC on the major crop production vary across areas. LC exerts significant impacts on the production of major crops in the central and eastern Hubei, and this effect persists to the following year. Similarly, this influence also exists in the southwestern and northern area, while becomes insignificant in the following year. No significant effect of LC variables is found in the northwestern area. These findings may provide reference for the government to address LC inefficiency and food security problems, and an effective and innovative mechanism combining the agricultural production, land consolidation and meteorological factors needs to be established to ensure food security and long-term and stable agricultural production. In addition, the regional difference in natural conditions and LC orientations should also be considered. 相似文献
44.
传统的由计算机控制的门禁系统需要构建专用的控制网络,并且不能进行局域网之外的无线远程控制;而以IP通信为基础的融合通信,把计算机网络与传统通信网络融合为一体,将数据、音视频融合在一个网络平台上;本文实现的门禁系统,利用IP网络,将门禁和IP融合通信达成一个有机的整体,是一种能实现无线WIFI控制的门禁系统。 相似文献
45.
针对高职教育发展的新形势、新政策、新要求,中高职三二分段教育成为高职教育的一部分,传统大学生素质拓展系统均适用于普通高校,设计开发一个适用于高职教育,针对中高职学生特点、职业教育培养目标的学生素质拓展系统非常有必要,有利于职业技能人才的全面培养,也减轻了学校相关工作人员的工作量,为师生带来方便。 相似文献
46.
基于行业化的石油勘探开发项目监督管理体系研究 总被引:1,自引:0,他引:1
为了找出适宜行业发展的监督管理体制,在国内外相关研究成果的基础上,分析了我国石油勘探开发项目监督管理的现状。针对现行的甲方一体化监督存在的问题,提出了由三大石油公司联合,建立石油行业层面的勘探开发项目监督管理体系,对石油勘探开发项目实行全行业统一、规范的标准化监督管理。阐述了构建基于行业化的石油勘探开发项目监督管理体系的主要做法和监督管理机制的运行。 相似文献
47.
《Food Policy》2014
The paper analyses farm worker welfare on three different types of farms in Kenya producing vegetables for export. The three types of farms differ by certification to international production standards as well as by size. A multidimensional approach measures welfare using human capital, income, physical and mental health, and life satisfaction. The findings suggest that GlobalGAP certification has a positive impact on worker welfare as farm workers are given more training. Workers on large certified farms earn more than those on small farms but also show more health problems. Certification on small farms is associated with higher satisfaction of workers with their life compared to workers on non-certified small farms. From a development policy perspective this paper does not support a clear cut policy on which types of farm to support as overall benefits of a support strategy will depend of the number of beneficiaries reached through the different farm types. 相似文献
48.
本文阐述了复合调味料食品生产审查的前期工作、申请受理、技术审查和许可审批等方面的内容,论述了复合调味料生产技术审查的相关标准执行要点及存在问题,旨在引导企业在复合调味料国家食品安全生产规范下开展复合调味料的规范化生产及技术创新,实现复合调味料绿色、安全生产的目标. 相似文献
49.
以豌豆粉丝废水分离渣为原料,对豌豆纤维的提取过程进行研究.通过耐高温α-淀粉酶、糖化酶、蛋白酶多酶分步水解的方法,去除豌豆渣中的淀粉和蛋白质.结果表明,耐高温α-淀粉酶添加量1.2%,反应温度为90℃,反应时间为60 min的条件下,豌豆膳食纤维的提取率最高;糖化酶加酶量为4.5%,反应温度为60℃,反应时间为110 min,pH为5.0的条件下,可达到良好的水解效果;蛋白酶的加酶量为1.0%,反应温度为55℃,反应时间为80 min,pH为8.5的条件下,酶解效果最佳.此时豌豆粉丝废水分离渣的膳食纤维含量可达到94% 以上. 相似文献
50.
服装模板缝制技术目前在服装生产流程有着比较重要的作用,其模板工艺的成败直接关系到产品质量的整体水平,传统的车工工艺需要较长的时间在实践中获得技艺的提升,工艺模板对于传统的缝制工艺是一种创新和改进。可以起到节约成本、提高生产效率、提高产品质量的作用。 相似文献