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1.
考虑到当前创新环境日益复杂化,科学与技术耦合系统已成为一个受系统内外因共同影响而发生演化的开放系统。在为耦合系统构建状态空间模型的基础上,通过求解该模型,刻画科学技术化强度和技术科学化强度,据此分析科学与技术互动产生的互补效应和成本效应,评价29个省份的科学与技术耦合效果,并测度地区科技发展所属耦合路径类型。研究表明,不同省份推进科学技术化进程和技术科学化进程的差异性显著;科学与技术耦合效果最佳并不能说明地区科技发展速度最快;绝大多数省份的科技耦合路径表现为科技中立路径,占比最小的路径为技术强势路径。基于不同省份的耦合情况差异,提出针对性建议。  相似文献   
2.
Driven by business strategies, digital transformation (DT) facilitates dramatic change in air passenger behavior. This study aims to determine and analyze different DT strategies (DTSs) with the help of an integrated SWOT-based fuzzy AHP-MARCOS methodology that is proposed for the first time in the literature for this purpose. This methodology is validated with a case study concerning the airline industry in Turkey. The weights of the SWOT factors are determined with the fuzzy AHP method. The fuzzy MARCOS approach is used to select the most suitable DTS. The most appropriate strategy is obtained as “focusing on differentiated digital customer experience and service quality by the adaptation of business models to DT to provide benefits”.  相似文献   
3.
This paper aimed to present an original approach for solving the aircraft stand allocation (SA) problem dynamically when due to operational disturbances, the planned allocation cannot be accomplished. The proposed Multiple-criteria Dynamic Stand Allocation (MDSA) method uses fuzzy logic to support decision-making under uncertainty. The MDSA method provides effective solutions in a short time, necessary for traffic management in case of delays, emergency, and untypical cases. It considers partially conflicting points of view of different airport users (airport managers, air traffic controllers, airlines, handling agents, and passengers) and may significantly support managers on the SA problem. The approach proposed can also be used for creating an initial SA plan for a considerable number of aircraft.  相似文献   
4.
Traffic congestion is an unpreventable problem to avoid in a transportation network and it has negative effects on traffic accident, time wasting, traffic delay and safety problem. Besides, in transportation networks, drivers do not want to deal with traffic jam while traversing between specified origin-destination pair. Therefore, traffic assignment (TA) is imperative to improve traffic management, transportation safety, time, and cost savings. System Optimum Traffic Assignment Problem (SOTAP) is a kind of TA model which aims to minimize the total system travel time on the network, and satisfies the flow conservation constraints. To model the SOTAP more realistically, the imprecise parameters can be taken as fuzzy. Therefore, in this paper, we focus on converting the conventional SOTAP to a fuzzy quadratic programming problem (QPP) which is named System Optimum Fuzzy Traffic Assignment Problem (SOFTAP). Here, link travel time is expressed with BPR function as generally used in the literature by converting to fuzzy except link-dependent parameters. Thus, the nonlinear objective function of SOFTAP is expressed in terms of fuzzy link flows and fuzzy link travel times. A solution approach from the literature is modified to the reconstructed SOFTAP.  相似文献   
5.
科技服务业产出测算是对科技服务业产出数据的统计与分析,加强科技服务业产出数据的规范统计和应用分析可为我国政府调整产业政策提供重要数据支撑。以科技服务业产出测算为研究对象,结合学者观点、国家标准及各级政府相关产业政策,提出将分支产业作为初始指标的横向统计思路,构建科技服务业产出测算指标体系。在数据收集方面,强调要做好“收”与“填”两个基本工作;在指标确立和数据收集基础上,进一步提出未来预测的两种方法,以此作为科技服务业产出数据预测的初步探索;提出应从统一数据统计标准、完善数据调查与公开制度、加强数据资源开发3个方面建立健全我国科技服务业产出数据测量与管理体制机制。  相似文献   
6.
This study highlights how social and commercial enterprises with local and global presence, balance their economic and social goals, to sustainably serve the bottom-of-the-pyramid (BoP) markets, predominantly in emerging economies. Employing the lens of transaction cost economics and configurational theory, we propose that successful venturing into the BoP markets, sensitize firms to create appropriate governance mechanisms for reducing transaction costs, resulting in creation and capture of values. Further, these mechanisms enable those firms to attain cost efficiency and sustainability in the process of fulfilling their social objectives. To that end, we employed the case survey method to analyse 42 cases, from the Harvard Business School repository, on multinational enterprises (MNEs) in emerging economies. Further, we used qualitative comparative analysis to uncover the various causal governance configurations that enabled those firms to sustainably serve the BoP markets.  相似文献   
7.
This research explores the physical infrastructure and flight consolidation efficiency drivers of Eurasian airports regarding their infrastructure and movement productivity levels. A novel Fuzzy Double-Frontier Network DEA (FDFNDEA) model is proposed to investigate the relationship between desirable (freight and passenger turnovers) and undesirable (pollutant emission levels due to aircraft movements) outputs against the respective infrastructure usage, fuel consumed, and movements performed at each of the 23 Eurasian airports from 2000 to 2018. This balance between desirable and undesirable outputs emerges spatially and temporally due to the evolution of the airport system's productive resources at each one of the Eurasian countries over the period observed. Shannon's entropy is used as the cornerstone to quantify the input and output vagueness of this evolution in Triangular Fuzzy Numbers (TFN), thus allowing the accurate building of alternative optimistic and pessimistic double-frontier efficiency. Differently from previous research, Shannon's entropy is the key for measuring input and output vagueness levels in light of the maximal entropy principle. This principle states that the distribution that best represents the current state of knowledge is the one with largest entropy. Maximal entropy yields bias-free decision-making in the sense that the input/output distributional profiles for Eurasian airports contain the maximal possible heterogeneity, working as a robust or best/worst-case scenario against eventual unconsidered assumptions. Hence, optimistic and pessimistic Malmquist Productivity Indexes (MPI) for overall and each stage productivity results are subsequently regressed against contextual variables related to airport characteristics and regional socio-demographic and economic indicators of each Eurasian country using bootstrapped Cauchy regressions. The findings revealed the spatial heterogeneity of productivity factors and airport performance across Eurasia. Results also demonstrated the negative impact of income inequality and the positive impact of private participation on technological progression in the Eurasian airport industry.  相似文献   
8.
The value relevance of comprehensive income (CI) compared to net income (NI) remains unresolved. We look at this issue in the Canadian market, using association methods to determine the value relevance of reporting CI and other comprehensive income (OCI) components for stock prices and returns. The sample consists of all the firms in the S&P/TSX Composite Index that prepared their financial statements according to Canadian standards or International Financial Reporting Standards (IFRS) over the 2008–2016 period. Although we find no evidence that CI is more value relevant than NI for stock prices and returns, we note that some OCI components are incrementally value relevant beyond NI for both amounts. In addition, financial services firms differ from other companies in terms of the relationships between some of their OCI components and prices or returns, with such firms even driving some relationships. Relationships between OCI components and prices or returns are also affected when data from the financial crisis period are excluded, with some relationships even changing after IFRS adoption. These results inform Canadian standard setters and financial statement users that OCI components are decision useful for the Canadian market.  相似文献   
9.
The traditional mean–variance approach has been complemented by alternative theories that use risk measures different from standard deviation of returns or involve additional distributional features of returns like skewness and kurtosis. We propose a portfolio choice model that combines different distributional characteristics of the returns in the decision-making making process, considering preferences of investors which are modeled as non-statistical uncertainties of investors using fuzzy theory. We use 20 stocks of the S&P500 from January 2013 to December 2017. We assess the obtained portfolios’ performance, and the diversified behavioral portfolios outperform than the mean–variance portfolio. This methodological proposal can be seen as a strong managerial tool to make investment portfolio decisions.  相似文献   
10.
Online-to-offline (O2O) has become a rapidly growing e-commerce model worldwide, but the factors influencing consumers' purchase decision-making have not been examined well. After exploring the working mechanism of the O2O model, we extract eleven indexes of consumers' overall evaluation in the O2O model with Crawlzilla and R techniques. Social network analysis (SNA) is adopted to build social networks reflecting consumers' overall evaluation in the O2O model. Based on the modified social network and the extracted subgraph, this study (N = 768) reveals consumers' overall evaluation behavior patterns in the O2O model by calculating network density, central potential, edge betweenness. The results show that shoppers overall evaluate the eleven indexes, especially perceived product quality, online product price, promotion intensity, business reputation, and product brand, which reflects the significant associations between the indexes. Among all the eleven evaluation indexes, perceived product quality, online product price, and business reputation dominate consumers’ decision-making behavior. When making purchase decisions, consumers not only overall consider online product price, perceived product quality, and business reputation but also balance perceived product quality, business reputation, and promotion intensity. Finally, we make some suggestions on marketing strategy for e-commerce companies.  相似文献   
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