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31.
Although a research base is beginning to emerge in relation to the peer-to-peer accommodation phenomenon, the voices of residents are seldom heard in this scholarly literature. This study uses Social Exchange Theory to examine resident perceptions regarding the impact of P2P accommodation growth, and specifically Airbnb, on their neighbourhood. Fifty-one semi-structured interviews were employed to illuminate understanding of how resident perceptions are formed in relation to the exchange relationship with Airbnb guests. Findings reveal a dominance of negative perceptions of socio-economic and environmental impacts. The study also contributes a typology of residents, based on their perceptions and behaviour towards associated impacts, which may guide policymakers and practitioners towards the adoption of an anthropocentric approach on P2P accommodation. The study concludes with a discussion of theoretical and practical implications.  相似文献   
32.
The sharing economy is a new phenomenon that has considerable implications for traditional industries in general and the hospitality sector in particular. Although some recent studies have investigated the effects of sharing economy on the hotel industry, they primarily focused on quantifying its effects which are not exploratory for a phenomenon. This study attempts to achieve two research objectives. First, an exploratory qualitative method via a semi-structured in-depth interview is employed to investigate the impacts of P2P accommodation on the industry from hoteliers’ perspectives in China. Second, the current study provides valuable insights about traditional hotel marketing and operations. A social science perspective is proposed because prior hospitality research, merely in its commercial sense, fails to capture the essence of hospitality. Results indicate that P2P accommodation has effects on the hotel industry in terms of host–guest interactions, product offerings, staff empowerment, and platform collaboration. The study also suggests that the extent to which P2P accommodation impacts the hotel industry is different in terms of hotel star ratings and operating model. P2P accommodation and the hotel industry in China have a supplementary relationship. This study contributes to social studies of the hospitality literature by gaining insights from hotel senior management level. It also has great implications for the hotel marketing and management practices within the sharing context.  相似文献   
33.
In contingent valuation, despite the fact that many externalities manifest themselves as costs to some and benefits to others, most studies restrict willingness to pay to being non‐negative. In this paper, we investigate the impact of allowing for negative, zero and positive preferences for prospective changes in woodland cover in two UK national parks, the Lake District and the Trossachs. An extended spike model is used to accomplish this. The policy implications of not allowing for negative values in terms of aggregate benefits are also investigated, by comparing the extended spike model with a simple spike making use of only zero and positive bids, and a model which considers positive bids only. We find that ignoring negative values over‐states the aggregate benefits of a woodland planting project by up to 44%.  相似文献   
34.
目的 MDM2、PTEN基因表达与贲门癌发生发展关系的研究。方法用免疫组化S-P法检测32例贲门癌组织及18例正常贲门粘膜组织中MDM2和PTEN表达情况。结果贲门癌组织中MDM2表达34.4%,显著高于正常贲门粘膜组织(P<0.05),且与贲门癌淋巴结转移、浸润深度呈正相关。PTEN在贲门癌组织中的表达40.6%,显著低于正常贲门粘膜组织(P<0.05),且与贲门癌淋巴结转移、分化程度相关。结论 MDM2和PTEN异常表达与贲门癌的关系密切,共同参与了贲门癌的发展、转移及浸润。  相似文献   
35.
用MPR-2模型计算溶质在含有和不含有夹带剂超临界CO2中的溶解度,把超临界CO2和夹带剂视为一个拟组分,并根据VDW-1混合规则求出拟组分的方程参数,将超临界三元体系的相平衡问题简化为超临界二元体系的相平衡问题。关联和计算了8种溶质(共268个数据点)在超临界CO2中的溶解度,模型计算值与文献的实验值相吻合。  相似文献   
36.
利用投入产出分析方法,选用工业SO2为污染指标,分部门对我国入世后工业品贸易中污染流的变化进行了研究。借鉴贸易的环境效应的分析框架,分析了入世后工业品贸易中污染流变化的原因。结果表明,2001-2004年,我国工业品贸易中的污染流为负;2005年,我国工业品贸易中的污染流为正。贸易规模扩大在污染流的增加中起了主要作用,贸易结构的改变也在一定程度上导致了我国污染流入的增加。  相似文献   
37.
针对卫星数字化视频广播第二代标准(Digital Video Broadcasting-Satellite -Second Generation,DVB-S2)中的多进制幅度移相键控(Multiple Amplitude and Phase-Shift Keying,MAPSK)和多进制正交幅度调制(Multiple Quadrature Amplitude Modulation,MQAM)信号的调制识别,提出了基于位同步的识别方法。首先利用信号星座图特征对信号包络进行位同步,然后统计信号码元的幅度值个数及其幅度值分布提取统计特征参数,最后利用特征参数完成识别。仿真结果表明,所提算法在载波频率等参数未知的条件下,能够有效对信号进行调制识别。  相似文献   
38.
崔鑫生  郭龙飞  李芳 《财贸经济》2019,40(4):100-115
本文使用能够由企业判断反馈的、具有省域区分度的变量,通过问卷调查测度了中国的贸易便利化水平,并在此基础上使用开埠通商历史作为工具变量,从贸易创造和贸易转移的视角,用引力模型实证研究了贸易便利化对中国各省份国际贸易和省际贸易的影响及其作用机理。结果显示,在控制关税等因素的情况下,贸易便利化水平的提升能够大幅提升我国各省份的对外贸易;不同地区贸易便利化作用的差异也揭示了我国对外开放的节奏和效果;虽然贸易便利化会带来贸易转移效应,短期抑制省际贸易,但是它能够通过国际贸易促进省际贸易,从而提高国内经济相互融合的水平。  相似文献   
39.
We investigate the performance of the ordinary least squares (OLS)‐, M‐, MM‐, and the Theil–Sen (TS)‐estimator for crop yield data analysis in crop insurance applications using Monte Carlo simulations. More specifically, the performance is assessed with respect to trend estimation, prediction of future yield levels, and the estimation of expected indemnity payments. In agreement with earlier findings, other estimators are found to be superior to OLS in simple regression problems if yield distributions are outlier contaminated and heteroscedastic. While this conclusion is also valid for subsequent applications such as yield prediction and the estimation of expected indemnity payments, the difference between the considered estimators becomes less distinct. For these applications, we find particularly the M‐estimator to be a good compromise between high‐breakdown (very robust) estimators and the very efficient OLS‐estimator. Because no regression technique dominates all others in all applications and scenarios for error term distributions, our results underline that the choice of the estimation technique should be dependent on the purpose of the crop yield data analysis. However, alternative estimators such as M‐, MM‐, and TS‐estimator can reduce (and bound) the risk of unreliable or inefficient crop yield data analysis in crop insurance applications.  相似文献   
40.
Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non‐parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota.  相似文献   
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