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131.
将能源消费控制在一个合理的水平对于我国实现能源与经济、环境协调可持续发展具有重大的战略意义。简要分析了我国实施能源消费总量控制的必要性,从产业结构调整、能源生产方式变革、能源利用方式变革3个方面分析了总量控制的途径,并结合经济增长的不确定性提出了实现总量控制目标的政策及有关建议。  相似文献   
132.
国产引进型300MW汽轮机通流部分改造及效益分析   总被引:1,自引:0,他引:1  
分析了国产引进型300MW双缸双排汽凝汽式汽轮机热耗率大、经济性差的原因。采用全三维技术对汽轮机高中压通流部分进行改造,设计使用了先进的子午收缩型调节级和弯扭马刀叶片,有效提高了机组的经济性和可靠性。该技术在江西丰城发电厂4×300MW机组上的应用经验,可为其他同类机组增容降耗改造提供借鉴。  相似文献   
133.
E. coli O157:H7 is an important source of foodborne disease. The E. coli pathogen occurs naturally within the rumen of livestock (including cattle) and does not affect the health of the cattle, however, can be a source of cross-contamination during food processing or environmental contamination of drinking and irrigation water supplies. A vaccine to reduce the risk of cattle shedding E. coli is licensed for use in Canada and the US, however, adoption of the vaccine by cattle producers has been extremely low. Using data from a survey of cow–calf producers in western Canada, the influence of a set of thirteen incentives to encourage adoption of the vaccine is examined using Best–Worst Scaling. Incentives include policy interventions, market/supply chain incentives, production protocol incentives, and producer reputation incentives. Heterogeneity in producer responses to the incentives is evident and is further explored with a Latent Class Cluster analysis. Results suggest that a ‘one size fits all’ policy to encourage adoption of an E. coli vaccine by cattle producers may be challenging.  相似文献   
134.
    
The entire food value chain and diet of low and middle income countries (LMICs) are rapidly shifting. Many of the issues addressed by the nutrition community ignore some of the major underlying shifts in purchases of consumer packaged foods and beverages. At the same time, the drivers of the food system at the farm level might be changing. There is a need for the agriculture and nutrition communities to understand these changes and focus on some of their implications for health. This rapid growth of the retail sector will change the diets of the food insecure as much as that of the food secure across rural and urban LMIC’s. This short commentary contents that current research, programs and policies are ignoring these rapid dynamic shifts.  相似文献   
135.
从OECD国家发展历程看我国2020年能源电力消费   总被引:1,自引:2,他引:1  
详细分析了OECD 10个主要国家在工业化进程中的能源和电力消费趋势。分析结果表明:在工业化和现代化的进程中,电力消费的增长速度始终快于一次能源消费;后发工业化国家的能源和电力消费增速远快于先行工业化国家,各国电力消费比重都在不断攀升。因此,在21世纪中叶我国全面实现工业化、基本实现现代化之前,无论是能源电力消费的总量还是人均指标,我国的一次能源和电力消费都将伴随着工业化进程继续快速增长,而目前我国接近发达国家的电力消费比重还将继续上升。情景分析表明,2020年,我国人均能源消费将达3.18~4.95tce,能源消费总量将达44.2亿~68.8亿tce;人均用电量增至5240~8090kW·h,全社会用电量达到7.3万亿~11.2万亿kW·h,需要15.8亿~24.4亿kW发电装机容量,人均装机约1.137~1.755kW。  相似文献   
136.
    
Retailer initiated food quality standards are important elements to market food and agricultural products. However, farmers’ certification proceeds at an unequal speed worldwide with some countries representing a large number of certified producers and others representing very few, if any. This study aims at analysing the adoption of two private food standards, BRC Food Technical Standard and GlobalGAP, at an aggregated cross-country level using data of 2007. Negative binomial models are applied to quantify the determinants of standards’ spread at an aggregated level. The results of the econometric analysis reveal some (potential) barriers for farms and firms in developing countries to access this type of organisational innovation. Certificates of both standards seem to be issued more likely in countries with established trade relations with Germany, the Netherlands and the United Kingdom, home countries of the standards. Furthermore, larger countries and countries with better institutional quality host more certified firms. Finally, a country’s level of economic development displays a clear non-monotonic relationship to the number of certified enterprises. Although no evidence for a general exclusion of developing countries can be found, the main implication of this paper is that third-party certification for export purposes seems to reinforce already existing trade relations, potentially hampering new entrants.  相似文献   
137.
    
Using three waves (2008/09, 2010/11, 2012/13) of the Tanzanian National Panel Survey, this study investigates the impact of maize price shocks on household food security. Between 2008/09 and 2012/13, calorie intake stagnated for urban households, yet sharply deteriorated for rural households. The latter was driven by a significant decline in the consumption of the major staple maize which showed strongest price hikes among all major food items. Fixed-effects regressions indicate a clear negative relationship between maize prices and average household energy intake. Almost all population groups were found to be negatively affected by maize price shocks, with rural landless households being the most vulnerable group. In particular, a 50 percent rise in maize prices decreases caloric intake for rural (urban) households on average by 4.4 (5.4) percent, and for rural landless households by 12.6 percent. Results further indicate that subsistence agriculture can act as an effective strategy to insure against food price volatility.  相似文献   
138.
Household Consumption and Expenditures Surveys (HCES) are increasingly being used to make inferences about individual food consumption, despite the fact that they collect food data at only the household level. Usually the analysis assumes that the household’s food is distributed among its members in direct proportion to each member’s share of the household’s total energy requirements; what is referred to as the adult male equivalent (AME) approach. Using the 2011–2012 Bangladesh Integrated Household Survey—which collected consumption data for all members of rural households using combined 24-hour recall (24HR) and food weighing methods—this study directly compared probability-based average estimates of intakes, intake gaps, and the prevalence of inadequacies as estimated by the 24HR and those calculated using the AME approach for energy and each of four micronutrients: vitamin A, iron, zinc, and calcium.At the population level, for iron, vitamin A, and calcium, more than 97% of all individuals had the same estimated prevalence of adequate or inadequate nutrient intakes using 24HR and AME-based estimates. In the case of energy and zinc, roughly 77 and 83% of the sample population had identical adequacy statuses, respectively. The magnitude of inadequacies (the nutrient gaps) differed by 8 percentage points for energy and less than 3 percentage points for the four micronutrients. Disaggregating intakes and inadequacies by age groups revealed that the vast majority of variance between the two methods was highly concentrated in the first few years of life. Children 3 years of age and younger constituted 7.5% of the population but had 13.1% of the inconsistencies in intake adequacy status. 54% of children 3 and under had at least one pair of inconsistent prevalence estimates. While there are important differences in the levels of estimated energy and micronutrient intakes using 24HR and the AME-based estimates for children 3 and under, the results are remarkably comparable for the rest of the population.  相似文献   
139.
    
Using nationally-representative household survey data and confidential geo-coded data on violent incidents, we examine the relationship between conflict and food insecurity in Afghanistan. Spatial mappings of the raw data reveal large variations in levels of food insecurity and conflict across the country; surprisingly, high conflict provinces are not the most food insecure. Using a simple bivariate regression model of conflict (violent incidents and persons killed or injured) on food security (calorie intake and the real value of food consumed), we find mixed associations. But once we move to a multivariate framework, accounting for household characteristics and key commodity prices, we find robust evidence that in Afghanistan levels of conflict and food security are negatively correlated. We also find that households in provinces with higher levels of conflict experience muted declines in food security due to staple food price increases relative tohouseholds in provinces with lower levels of conflict, perhaps because the former are more disconnected from markets. Gaining a better understanding of linkages between conflict and food insecurity and knowing their spatial distributions can serve to inform policymakers interested in targeting scarce resources to vulnerable populations, for example, through the placement of strategic grain reserves or targeted food assistance programs.  相似文献   
140.
    
Many regions on earth face daily limitations in the quantity and quality of the water resources available. As a result, it is necessary to implement reliable methodologies for water consumption forecasting that will enable the better management and planning of water resources. This research analyses, for the first time, a large database containing data from 2 million water meters in 274 unique postal codes, in one of the most densely populated areas of Europe, which faces issues of droughts and overconsumption in the hot summer months. Using the R programming language, we built and tested three alternative forecasting methodologies, employing univariate forecasting techniques including a machine-learning algorithm, with very promising results.  相似文献   
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