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51.
决策融合是提高合成孔径雷达(Synthetic Aperture Radar,SAR)目标识别性能的重要手段,然而,可靠性较弱的决策往往会导致最终决策融合的效果变差。将可靠性分析引入基于决策融合的SAR目标识别方法中,分别计算各个决策的可靠性系数并选取可靠性的决策参与最终的决策融合。为了验证方法的有效性,分别将提出的可靠性分析应用于多特征决策融合以及多分类器决策融合并基于MSTAR(Moving and Stationary Target Acquisition and Recognition)数据集进行了目标识别实验。在基于主成分分析、线性鉴别分析和非负矩阵分解三种特征进行多特征决策融合的条件下,所提方法和直接进行决策融合的方法的识别率分别为97.47%和96.50%。在基于K近邻、支持向量机和稀疏表示分类器的多分类器决策融合中,所提方法和直接进行决策融合的方法的识别率分别为97.10%和96.28%。实验结果充分证明了所提方法的有效性。 相似文献
52.
Brands take advantage of technology, social media and constant connectivity to foster organic consumer engagement and interactions towards co-creating personalised customer service. Real-time service offers dynamic engagement with connected consumers. Brands in tourism and hospitality use technology to dynamically enhance consumer experience through co-creation. The integration of real-time consumer intelligence, dynamic big data mining, artificial intelligence, and contextualisation can transform service co-creation by mobilising recourses in the ecosystem. Nowness service emerges by dynamically engaging consumers in experience cocreation in real time. It has five interconnected characteristics that revolutionise the tourism and hospitality, namely: real-time, co-creation, data-driven, consumer-centric and experience co-creation. 相似文献
53.
By integrating Battese and Coelli’s (1995) model and the spatial autoregressive model (SAR), a spatial autoregressive stochastic frontier model for panel data is developed. The main feature of this frontier model is a spatial lag term of explained variables and the joint structure of a production possibility frontier with a model of technical inefficiency. The model addresses both spatial dependence and heteroskedastic technical inefficiency. This study applies maximum likelihood methods considering the endogenous spatial lag term. The proposed model nests several existing models. Further, an empirical analysis using data on the Japanese manufacturing industry is conducted and the existing models are tested against the proposed model, which is found to be statistically supported. The findings suggest that estimates in the existing spatial and non-spatial models may exhibit bias because of lack of determinants of technical inefficiency, as well as a spatial lag. This bias also affects the technical efficiency score and its ranking. 相似文献
54.
《Telecommunications Policy》2019,43(8):101822
Disparity in the level of digitalization is a crucial driver of economic inequality in an economy. Although a pocket of its population is still bereft of the benefits of digitalization, India currently has the second highest number of internet subscribers in the world despite the nation's late adoption of digital technology. An accurate assessment of the current state of digitalization in the country is required for devising effective initiatives towards building a Digital India and bridging the nation's internal digital divide. Considering 17 major Indian states and 21 variables for 10 years, we constructed a composite index of digitalization with the help of Principal Component Method (PCM). This paper identifies factors responsible for the digitalization divide across states. In the second part of the analysis, the study confirms, with the help of club convergence test, the absence of overall convergence towards digitalization and the existence of the non-convergent group. This paper also shows that the non-convergent group of states are at the bottom of the ranking table which indicates the need for greater attention to initiatives to bridge the digital divide. 相似文献
55.
Corporate social responsibility (CSR) has attracted wider research interests over recent decades. While some studies have examined the impact of CSR activities on firm competitive advantage (CA), the findings so far remain contradictory. Moreover, the role of export orientation, firm strategy, and structure on the association between CSR and CA has not been explicitly examined. Thus, the purpose of this study is to examine the moderating role of export orientation, firm strategy, structure, and firm size on the association between CSR and CA. Using a sample of 179 responses from management staff in organizations across five sectors in a developing country context of Ghana, the study found positive effects of CSR on CA. The study contributes to the resource‐based view (RBV) scholarship by confirming the important complementary effect of export orientation and organizational structure as important resources and capabilities on the CSR–competitiveness relationship. However, no evidence of a moderating effect of firm strategy, or firm size on the CSR–CA relationship was found. These findings are instructive, impactful, and enrich the existing literature on CSR and strategy. Implications for theory and practice are also discussed. 相似文献
56.
Natalya Vinokurova 《Business History》2019,61(6):1005-1050
This article traces the developments in the market for residential mortgage-backed securities (MBS) during the period 1970–2008. Drawing on an analysis of trade publications, business press, and interviews with practitioners, it shows that an MBS market meltdown in 1994 provided clear signals of problems with MBS. The market participants did not re-evaluate their use of risk management tools or adjust security design in response to the 1994 crisis, suggesting a lack of understanding of the implications of the crisis. The 1994 meltdown showed that MBS were vulnerable to systematic risks and that these risks could precipitate an MBS market crash. Furthermore, the 1994 meltdown demonstrated that large-scale investment in MBS could affect the primary mortgage market, thereby rendering the MBS risks unpredictable. After 1994, MBS investment shifted to MBS backed by mortgages with default risk – a development that led to the crash of 2008. By drawing parallels between the 1994 and 2008 crises, this article shows how the MBS market failed to self-correct. The results suggest that financial market participants do not always incorporate relevant information in their decision-making and that market participants have difficulties in both foreseeing the effect of financial innovations on markets and interpreting these effects. 相似文献
57.
The objective of this research is to identify which are the key variables for designing a message in a social network that can be used by an advertiser to generate Positive/Negative Engagement. The message’s design variables have been classified into four main groups: (i) Message Tools (presence of text, images, video, labels, applications, interactive games and events calendar or others), (ii) Appropriate Message Structure (length and intelligibility), (iii) Informative Cues (links to the brand, orientation towards the product or the brand, topics relevant to the audience, and a remuneration’s promise) and (iv) Persuasive and Emotional Cues (emotional signals, valence, endorsement and influencer mentions). The focus has been a tourist destination: Brand Spain that is advertised through Facebook. A content analysis was carried out and regression analysis with optimal scaling was used on 180 Spain brand’s publications; 57,626 audience reactions to such publications; and 1361 audience comments on the Brand Spain Official Fan Page. According to our results, from the four blocks of predictive variables, only two of them are useful to predict Positive/Negative Engagement: (i) the use of Message Tools (videos), and (ii) the use of informative cues (relevant topics, links on posts, and post’s orientation towards product). 相似文献
58.
Linnea Haag Uni Sallnäs Erik Sandberg 《International Review of Retail, Distribution & Consumer Research》2019,29(3):321-339
ABSTRACTMarket-oriented aspects of retail internationalisation have received a lot of research attention since the 1990s. However, beyond these aspects lies also supply-chain oriented capabilities that are necessary for retailers to successfully internationalise into foreign sales markets. By using a perspective based on resource-based theories, this paper explores supply-chain oriented capabilities that facilitate retail internationalisation. The research is based on a multiple case study of three Swedish retailers. Through the perspective of research based theories, specifically capabilities, the empirical data is studied in a single-case as well as a cross-case analysis. Findings reveal three supply chain-oriented capability categories (leadership capability, integration capability and learning capability) of importance for retail internationalisation. Resources necessary for the capabilities are to be found internally at the retailer, but also externally at other firms. This research adds to the market-oriented knowledge on retail internationalisation by adding a supply-chain oriented perspective. Further, it provides an understanding of the early phases of retail internationalisation. 相似文献
59.
60.
针对无线传感器网络分簇算法中能量分布不均衡导致的"热区"和簇头负载过重问题,提出了一种基于PSO算法优化簇头选举的非均匀分簇算法。在候选簇头选举和竞争半径计算过程中综合考虑节点动态能量、节点密度和节点距基站距离,将网络进行非均匀分簇,并引入PSO算法进行最终簇头选举。根据节点能量、节点密度和距基站距离确定簇间单跳多跳结合的路由规则,选取代价函数小的节点作为下一跳节点。基于节点信息熵确定融合阈值,进行簇内数据融合剔除冗余数据。仿真结果表明,改进算法的数据传输量比EEUC算法和UCRA算法分别提高了20%和10%,提升了数据的融合效率,有效延长了网络生命周期,簇头能量消耗得到均衡,减少了网络能量消耗,网络的整体性能显著优于其他对比算法。 相似文献