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41.
Students involved in holistic technological practice need to develop an understanding of technological practice outside the classroom and to participate in tasks set as close as practicable to actual technological practice. This paper investigates the context of assessment and its relationship to achievement and the importance of teacher knowledge to student technological practice. I argue that ‘out of context’ assessment tasks do not give an accurate indication of achievement levels of the children assessed. Introduced is the Model of Student Technological Practice, which identifies four constraints that influence student technological practice. A significant factor is teacher knowledge, as it impacts greatly on the quality of feedback given to students by their teachers. Timely teacher intervention and formative assessment feedback will alter student technological practice and should improve the students’ likelihood of developing successful outcomes.  相似文献   
42.
阐述了计量标准考核的现状及存在问题,提出了在计量标准考核中运用数理统计技术的具体方法、步骤,即通过核查标准建立测量过程统计控制,进而实现实验室的运行控制。  相似文献   
43.
行业平均投资利润率和行业平均投资利税率是投资者进行投资机会选择的主要参考依据之一,是投资者对其投资项目收益的最低期望要求。从投资者角度来讲,恰当地确定平均投资利润率和行业平均投资利税率是一个相当重要而又比较棘手的问题。文章主要讨论了如何确定油气田勘探开发项目经济评价中平均投资利润率和行业平均投资利税率的一种简单方法。  相似文献   
44.
油气管道完整性评价的数据支持系统   总被引:2,自引:0,他引:2  
开发了管道完整性评价的数据库系统,介绍了该软件系统的结构、模块、特点、主要功能和操作界面。  相似文献   
45.
对石油资源价值评价中的4个成本因素之一——运销成本级差因素进行了讨论。文中分析了运销成本级差因素的组成因子之后.建立对之进行测算的数学模型,并就两个油田的实测数据给出了计算结果。  相似文献   
46.
本文以宁夏工商职业技术学院机电工程系《典型电气控制设备的安装》考试考核方式改革为例,分析了传统的教学方法和教学内容已经不能适应人才培养的需要。怎样按职业教育的规律和特点培养出符合企业需要的人才是目前高职院校的头等大事,机电工程系经过多年的研究和实践,探索出了校企合作、工学结合的人才培养模式是在高等职业教育中一种非常有效的人才培养模式,而这种人才培养模式的实施,其关键在于教育教学的课程改革。由此引出了课程体系构建、教学内容选择、教材编写、双师素质教师的培养、教学环境建设、教学方法、考试考核方式改革和教学组织等一系列课题。  相似文献   
47.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment.  相似文献   
48.
Background: QALYs are widely used in health economic evaluation, but remain controversial, largely because they do not reflect how many people behave in practice. This paper presents a new conceptual model (Load Model) and illustrates it in comparison with the QALY model.

Methods: Load is the average annual weight attributed to morbidity and mortality over a defined period, using weightings based on preference judgements. Morbidity Load is attributed to states of illness, according to their perceived severity. When people are in full health, Load is zero (no morbidity). Death is treated as an event with negative consequences, incurred in the year following death. Deaths may be weighted equally, with a fixed negative weight such as ?100, or differ according to the context of death. After death, Load is zero. In a worked example, we use the standard gamble method to obtain a weighting for an illness state, for both Load and QALY models. A judge is indifferent between certainty of 1.5 years’ illness followed by death, or a 50/50 chance of 1.5 years’ full health or 1-year illness, each followed by death. The weightings calculated are applied to a hypothetical life, 72 years in full health followed by 3 years with illness then death, using both models. Three other hypothetical outcomes are also compared.

Results: For an example life, the relative size of the morbidity component compared with the mortality component is much higher in the Load model than in the QALY model. When comparing alternative outcomes, there are also substantial differences between the two models.

Conclusions: In the Load model the weight of morbidity, relative to mortality, is very different from that in the QALY model. Given the role of the QALYs in economic evaluation, the implications of an alternative, which generates very different results, warrant further exploration.  相似文献   
49.
While a careful and accurate debt sustainability assessment (DSA) is crucial for an efficient macroeconomic management, the most widely used framework introduced by the International Monetary Fund (IMF) suffers from several drawbacks that render its results overoptimistic and misleading. In this article, we correct the methodology by demonstrating how policy makers can develop country-specific “intermediate” forecasts of the determinants of debt dynamics, in addition to coherent “optimistic” and “pessimistic” scenarios. Our application to the case of Egypt illustrates that the debt-to-GDP ratio could increase to more than 100 percent by 2015, in contrast with the 61 percent projected by the IMF in 2010.  相似文献   
50.
In this study, ten bioenergy crop rotations (corn, corn-stover, sorghum, soybean, corn-soybean, corn-soybean-canola, corn-stover-soybean, miscanthus, switchgrass, and sorghum-soybean) were selected based on local stakeholder (economically motivated) and regulator (environmentally motivated) preferences. These crops were implemented on diverse landscapes (agricultural, marginal, and agricultural plus marginal lands) one at time for 17 years using a SWAT model of the Saginaw River Watershed in Michigan. The bioenergy crops were evaluated based on 100 percent, 50 percent, and zero percent weight assigned to both stakeholders’ and regulators’ preferences using analytic hierarchy process (AHP), an optimization and decision-making technique that aims to satisfy multiple conflicting objectives. The corn-soybean-canola rotation was selected in all landscapes based on economic benefits (stakeholders’ preferences). Meanwhile, perennial grasses (miscanthus and switchgrass) were selected based on environmental benefits (regulators’ preferences), because they maintain permanent cover, require fewer inputs than traditional row crops, and are less management intensive. When implementing bioenergy crops on marginal lands, pollution generation greatly increased at the field level, indicating that these lands are likely not viable for bioenergy crop production to meet potential future renewable energy demand.  相似文献   
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