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21.
Choice experiments (CE) have become widespread as an approach to environmental valuation in both Australia and overseas. However, there are few valuation studies that have addressed natural resource management (NRM) changes in Tasmania. Furthermore, few studies have focussed on the estimation of estuary values. The CE study described in this paper aims to analyse community preferences for NRM options in the George catchment, Tasmania. Catchment health attributes were: the length of native riverside vegetation; the number of rare native animal and plant species in the George catchment; and area of healthy seagrass beds in the Georges Bay, which was used as a measure of estuary condition. Mixed logit models with interactions between socio‐economic variables and the choice attributes were estimated to account for systematic and random taste heterogeneity across respondents. Results reveal considerable variation in preferences towards the attributes and show that value estimates are significantly impacted by the way in which we account for preference heterogeneity. Preference heterogeneity thus needs to be considered when estimating community willingness‐to‐pay for environmental changes. This study further shows little responsiveness to the presented changes in estuary seagrass area.  相似文献   
22.
Many fundraising charities invest heavily in content marketing, often using consultants to direct their content-marketing efforts. Thus it is vital to establish whether certain key aims of content marketing suggested by literature in the field actually match the aspects of content marketing deemed most important by charity donors. This paper examines the significance attached by samples of charities, donors, and content-marketing consultancies to four possible major objectives of content marketing—the attainment of high–search-engine-results-page rankings, image enhancement through impression management, the stimulation of public perceptions of organizational transparency, and the creation of messages that “go viral.” Several major differences in perceptions emerged among the three groups, with substantial implications for how fundraising charities should manage their content-marketing programs and activities. Charity managements need to consider carefully and critically the possible returns on large-scale expenditures intended to pursue the putative aims of content marketing that are routinely advocated by practitioner and academic literature.  相似文献   
23.
In 2015, the Federal Communications Commission (FCC) imposed common carriage regulation—so-called Title II requirements—on previously unregulated broadband Internet service providers. The regime shift was premised on the FCC’s findings that such rules had demonstrably yielded economic gains. This paper evaluates the FCC’s empirical arguments and finds them uncompelling. Adjustments for inflation or general economic trends eliminate the effects cited by the FCC. Moreover, contrary to the Commission’s assessment, mobile services and broadband markets have shown notable growth in response to deregulatory events that reduce Title II requirements.  相似文献   
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This paper focuses on evaluating the economic potential and infrastructure requirements of hydrogen production from agricultural residues, a representative green energy pathway. A mixed-integer nonlinear programming model is constructed for finding the most efficient and economical configuration of the whole pathway. Using northern California case studies, we found that hydrogen from agricultural wastes can be delivered at costs similar to producing hydrogen from natural gas, a non-renewable energy source. The potential impact of this energy pathway on local freight transport is also discussed depending on the choice of hydrogen delivery mode.  相似文献   
26.
The Jóór (Dior) soils of Senegal's Peanut Basin are inherently low in organic matter, limiting yields of millet and other crops and threatening the food security of smallholders. Focus groups and interviews were conducted in eight villages to characterise the site-specific fertility management by farmers in the Peanut Basin. Results of the qualitative survey revealed that farmers base management decisions on a series of fertility indicators that include type, colour, and texture of soil, presence of vegetation, and productivity in previous years. In an effort to equalise fertility across the field, farmers amend areas they classify as less fertile with decomposed manure and household waste from the family sëntaare (traditional pile) orwith compost from managed piles. On-site measurements of soil in areas of fields amended with compost or sëntaare material revealed significant increases in peanut and millet growth over unamended areas, but little difference between the effects of compost and manure. Similarly, chemical analysis revealed increased effective cation exchange capacity (ECEC) and nutrient concentrations (K, Mg and Al) in soils amended with compost or manure. Similarities in the chemical characteristics of compost and sëntaare material suggest that development workers could emphasise improved pile management rather than promoting more labour-intensive composting.  相似文献   
27.
So-called “spurious regression” relationships are generally accompanied by clear signs of residual autocorrelation. A conscientious researcher would likely re-estimate with an autocorrelation correction. Simulations indicate that resulting test statistics are close to true values, so do not yield spurious results.  相似文献   
28.
Previous research on the relationship between economic freedom and income inequality has produced mixed results. We provide a short survey of this literature, identifying potential causes for this empirical heterogeneity. Next, we replicate the results from two significant studies using six alternative measures of income inequality for an updated dataset of up to 112 countries over the period 1970–2010. Notably, we use the latest release of the Standardized World Income Inequality Dataset, which allows us to account for the uncertainty of the estimated Gini coefficients. We find that the results of previous studies are sensitive to the choice of country sample, time period and/or inequality measure used. We conclude with suggestions for future research in the area.  相似文献   
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The speed of the aging process is variable. Some individuals remain exceptionally fit beyond age 90, while others become frail and fragile early. Survival is better predicted by biological age (state of health, status of reserves) rather than chronological age (age in years since date of birth). The frail group shows a higher mortality compared to the robust group. When assessing the elderly in underwriting, it is important to note the usual chronic diseases such as cardiovascular disease, COPD, cancer risk, and so on. But because of its strong impact on prognosis, it is also important to assess frailty. Key features of frailty are social isolation, dependency in managing life activities and self-care, cognitive decline, shrinking of bone and muscle mass, and slow weight loss.  相似文献   
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