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971.
为了提高综合孔径辐射成像系统在地球物理摄动因素影响下的图像精度,对低轨星载综合孔径辐射成像系统的成像误差的修正方法进行了研究,提出了针对地球形状摄动、大气阻力摄动以及两种摄动共同作用的空域补偿动力学模型,结合空域摄动法和数值分析方法对这一空域误差补偿动力学模型进行了模型简化以及误差补偿算法的研究,并给出了空域补偿算法的流程图。仿真结果表明,所提出的空域补偿算法极大地提高了综合孔径辐射成像系统对于目标场景物体的恢复精度,有效降低了综合孔径辐射成像系统成像的摄动力误差。  相似文献   
972.
This study examines preferences for local foods by two distinct consumer groups: local residents and tourists. In an incentive-compatible framed field experiment, a series of dichotomous-choice tasks involving oyster purchases were completed by 758 individuals: 341 local residents recruited at a Division of Motor Vehicles office and 417 tourists recruited at a beach ferry terminal. The experimental design allowed us to investigate differences in preferences between tourists and local residents for locally produced oysters. Our estimates suggest both locals and tourists are willing to pay more for local oysters than for nonlocal ones, though this result is only statistically significant among tourists. The findings from this study shed light on potential designs for labels of food products, particularly when marketed in popular tourism areas.  相似文献   
973.
We report the first experiment to pair a three-player ultimatum/dictator game with a real effort task. The inclusion of the real effort task shifts the standard for division from simple egalitarianism towards relative performance; even in treatments in which roles and funds are exogenous. Additionally, we find proposers overcompensate themselves relative to their effort, and this additional compensation comes at the expense of powerless (third) players. Individual characteristics predict the nature of a proposals. Lastly, we find that responders’ choice to accept is based on their own and the powerless third party’s compensation.  相似文献   
974.
This study examines whether threat of stricter regulation influences the pricing behavior of firms. Using data on unregulated Swedish local district heating monopolists, we measure the threat level by the number of customer complaints about prices received by a national board. Exploiting a natural experiment, we find that firms reduce prices when customer complaints increase.  相似文献   
975.
This research investigates the role of a widely used, yet under-investigated packaging cue: the paper strip that wraps around books, known as the belly band. Drawing on cue utilization theory, we conducted a pilot study, a laboratory experiment and a field study in two real-life bookshops to analyze the effects of belly bands on consumers' responses, as well as on actual browsing and purchasing behavior. The results suggest that the belly band acts primarily as a visual cue; has a significant effect on actual browsing and purchasing behavior; and stimulates unplanned behaviors, producing a carryover effect on the assortment even if it does not alter the customer's budget.  相似文献   
976.
为研究缝洞型油藏溶洞中注水速度和黏度对水驱波及面积和油水界面的影响,利用Fluent数值模拟软件从流体力学角度对单缝洞油藏溶洞内流体流动进行了数值模拟,采用VOF模型对油水两项界面进行跟踪。研究发现,入口水速一定时,波及面积随着黏度的增大逐渐增大,油水界面呈对称均匀推进,黏度较小的原油水相会趋向中心线向洞口流动并产生漩涡,随着黏度逐渐增大,漩涡逐渐消失,驱替方式逐渐转变成活塞式驱替;原油黏度一定时,波及面积随着入口速度的增加而减小,油水界面呈对称趋势均匀推进,水速较大时水相会趋向中心线向洞口流动并有漩涡产生,随着入口水速增大,趋势逐渐明显。研究结果可为进一步完善缝洞型油藏溶洞内水驱过程中油水两相的流态分析提供参考。  相似文献   
977.
Aims: The aim of this study was to elicit the preference of patients with an anxiety disorder regarding treatment modalities. Understanding patients’ preferences could help optimize treatment uptake and adherence to therapeutic interventions.

Materials and methods: A discrete-choice experiment was used to elicit patients’ preferences with regard to four treatment characteristics: waiting time until first treatment, intensity of treatment, face-to-face vs digital treatment, and group size. In 12 choice sets, participants were asked to choose between two treatment alternatives. A random parameters logit model was used to analyse the data.

Results: A total of 126 participants, aged 18?years and older, currently or in the previous year in treatment for an anxiety disorder, completed the survey. Respondents preferred short (over long) waiting times, face-to-face (over digital) treatment, individual (over group) treatment and a treatment intensity of one session per week rather than two sessions per week or one session every two weeks. Waiting time and treatment intensity were substantially less important to patients than level of digitalization and group size. Heterogeneity in preference was significant for each attribute, and sub-group analyses revealed this was partly related to education level and age.

Limitations: The convenience sample over-represented the female and younger population, limiting generalizability. Limited information on background characteristics limited the possibilities to explore preference heterogeneity.

Conclusions: This study demonstrated how different treatment components for anxiety disorders affect patients’ preferences for those treatments. There is significant variation in treatment preferences, even after accounting for age and education. Incorporating patients’ preferences into treatment decisions could potentially lead to improved adherence of treatments for anxiety disorders.  相似文献   
978.
Hypothetical bias is tested based on inter- and intra-respondent comparisons of choice behavior, applying a hypothetical and real choice experiment. The inter-respondent comparison commonly applied in the environmental and agricultural economics literature consists of a control group of buyers who are asked to hypothetically choose between conventional and organic beans and an experimental group of buyers who are endowed to purchase the same beans using an identical experimental design. Hypothetical bias is tested by comparing inter- and intra-respondents’ (i) hypothetical and real choices, (ii) preference parameters of the estimated choice models related to hypothetical and real choices, and (iii) hypothetical and real willingness to pay (WTP). Choices in the experimental group are highly consistent when switching from hypothetical to real choices for this study's homegrown goods. However, after being endowed, the price sensitivity of lower income households drops, suggesting a house money effect. WTP derived from actual purchases is higher than WTP based on hypothetical choices, indicating a negative hypothetical bias, but differences are only significant in the case of the inter-respondent comparison. Actual prices paid by respondents in the field experiment appear to be considerably lower than the estimated WTP values and yield a mixed picture of hypothetical bias.  相似文献   
979.
Voting by Veto [VBV], developed by Dennis C. Mueller, is a two-stage voting mechanism for committee decision making. In the first stage, every member of the committee makes a proposal. The proposals are joined with the current status quo (or another fallback option). For the second stage, a random mechanism determines the order of voting and the committee members sequentially eliminate one alternative each. After every committee member has exercised her veto, a single winning alternative remains. Game theory predicts that the equality of the resulting distribution under VBV varies with group size. Hence, decisions in two-member groups should result in highly unequal distributions of benefits. With increasing group size, however, VBV should generate more equally distributed outcomes. We examine the effect of group size under VBV in a series of laboratory experiments where groups with a varying number of members play a ‘divide the dollar game’. Our results confirm that larger groups choose more equal distributions than smaller groups. However, we also find deviations from the model's predictions. Some committees in our experiment do not select Pareto-optimal alternatives. An exploratory analysis of possible explanations suggests that individual behavior is most likely motivated by a combination of material self-interest and social preferences such as reciprocity and fairness.  相似文献   
980.
The Korean government plans to improve the quality of its weather forecasting system in order to increase its public utility. The benefits arising from the implementation of this plan should be measured. To this end, this study applies a choice experiment to four attributes: the update frequency of both short- and medium-range forecasts, and the accuracy of both. A survey of 1000 randomly selected households was undertaken in Korea. In the study results, the marginal willingness-to-pays, respectively, for one more update of the short-range forecast per day, for a 1% increase in the accuracy of the short-range forecast, for changing the update frequency of the medium-range forecast from once a day (reference level) to twice a day, and for a 1% increase in the accuracy of the medium-range forecast as a result of improving the weather forecast service were estimated to be KRW 499.3 (USD 0.45), 108.3 (0.10), 346.5 (0.31), and 80.9 (0.07) per household per month. The findings can provide policy-makers with useful information for both evaluating and planning improvements in the weather forecasting system.  相似文献   
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