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1.
Despite the extensive amount of data generated and stored during the maintenance capacity planning process, Maintenance, Repair, and Overhaul (MRO) organizations have yet to explore their full potential in forecasting the required capacity to face future and unprecedented maintenance interventions. This paper explores the integration of time series forecasting capabilities in a tool for maintenance capacity planning of complex product systems (CoPS), intended to value data that is routinely generated and stored, but often disregarded by MROs. State space formulations with multiplicative errors for the simple exponential smoothing (SES), Holt’s linear method (HLM), additive Holt-Winters (AHW), and multiplicative Holt-Winters (MHW) are assessed using real data, comprised of 171 maintenance projects collected from a major Portuguese aircraft MRO. A state space formulation of the MHW, selected using the bias-corrected Akaike information criterion (AICc), is integrated in a Decision Support System (DSS) for capacity planning with probabilistic inference capabilities and used to forecast the workload probability distribution of a future and unprecedent maintenance intervention. The developed tool is validated by comparing forecasted values with workloads of a particular maintenance intervention and with a model simulating current forecasting practices employed by MROs.  相似文献   
2.
Despite the importance of facilities as primary sites for delivery of leisure and sport services, there has been a scarcity of academic literature on the provision of community sports facilities and the processes through which they are developed. In particular, this paper provides empirical analysis of leisure facility provision with a focus on practice and experience of policy and planning actors. By employing a case study approach and semi-structured interviews, the study identified a sharp contrast between the discourse of neo-liberalism and the realities of a highly regulated environment for the private sector under a national legislation of New Zealand, namely the Resource Management Act 1991. While both public and private actors recognised benefits of the resource consent process in mitigating the negative environmental impacts and facilitating public input, the findings also revealed its potential impediments to both private and philanthropic developments and their potential resultant benefits to communities and social citizenship due to its costly, restrictive and undifferentiated nature. Consequently, the paper suggests that future research needs to examine empirical evidence of how social citizenship and citizen engagement are enhanced by both public and private sectors through planning and development of community sports facilities and services.  相似文献   
3.
基于CFPS(2010)数据,实证分析计划生育政策对城乡收入差距的影响机制,并利用Oaxaca-Blinder分解法和RIF回归分解法测度了计划生育政策对城乡收入差距的贡献度。结果表明:(1)计划生育政策有利于子代收入的提高,且对城镇的收入边际效应大于农村;(2)政策允许家庭生育数量越多,越不利于农村家庭子代收入的提高,家庭一旦超生则会显著降低子代收入,而且相对于农村家庭子代而言,城镇家庭超生对子代收入的负向影响更大;(3)计划生育政策对城乡收入差距的拉力呈现出U型特征,对低、高收入群体的影响较大,而对中等收入人群的城乡收入差距贡献相对较小,其中政策允许生育胎数起到了决定性作用。因此,计划生育政策应统筹全局、因地制宜、奖惩兼施,以提高农村的人力资本水平和子女的教育质量,促使城乡居民生育率和人力资本水平趋同。  相似文献   
4.
“城市双修”的提出,促进了屋顶绿化的发展。将农业活动引入到校园建筑屋顶空间,增加城市的绿化率和人居空间环境的归属感,发挥积极的社会作用。通过实际案例对屋顶农场的概念、建设要求、设计及意义进行分析和说明。屋顶农场的建设,增加了学生们与大自然的亲密接触,丰富了课外活动,引导了学生们的自主学习和创新能力,还解决了生活中师生对部分食品的需求。通过案例研究,以期对城市建筑屋顶农场的推广有一定的促进作用。  相似文献   
5.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
6.
历史制度主义是新制度主义中的重要分支,强调政 策是随着时间的推移而被制度塑造的,存在着“路径依赖”现 象,这意味着在过去制度环境中做出的政策选择影响现在的政 策结果。中国城市治理制度深受苏联模式的影响,若想理解以 及应对规划管理中存在的问题,首先需探索其历史。提供了一 种从规划历史切入分析的视角以更好地理解与解决规划管理中 的现存问题,进而构建具有我国发展特色的规划管理理论分析 方法。首先探讨了历史制度主义在制度分析中的应用及优势, 然后通过探讨与分析我国绿地资源管理现状证明苏联模式如何 通过“路径依赖”影响现在的绿地资源管理机制,将历史制度 主义分析方法应用于理解我国的规划管理实践中,在我国自然 资源部成立的改革大背景下提出相应政策建议。  相似文献   
7.
研究目的:基于中国旅游景区功能演变、用地特征及问题分析,构建旅游景区用地分类体系,以期为旅游景区用地纳入区域土地利用提供理论基础,为旅游景区规划的深度编制提供实践依据。研究方法:通过调研和问卷厘清现状景区用地情况,对比借鉴相关用地分类体系,基于此构建旅游景区用地分类方案。研究结果:分析并阐明了旅游景区的功能演变、用地特征和现状问题,构建了2大类、9中类、28小类的景区用地分类体系,并与《土地利用现状分类》进行衔接。研究结论:建立可衔接且具可操作性的旅游景区用地分类体系,是实现旅游景区健康可持续发展与用地规范化管控的关键。  相似文献   
8.
国土空间用途的权衡决策方法研究   总被引:1,自引:0,他引:1  
研究目的:探索国土空间用途冲突协调路径,为中国"多规合一"及国土空间规划提供理论与方法指导。研究方法:在分析冲突根源的基础上建立国土空间权衡决策模型,构建"战略理性+技术理性+沟通理性"的国土空间权衡决策模式,并以丰县为例开展实证研究。研究结果:(1)国土空间利用的冲突本质上是利益相关者之间的利益冲突,只有利益权衡,没有利益优化;(2)国土空间权衡决策准则、国土空间价值评估、价值权衡和沟通定权共同组成国土空间权衡决策模式;(3)实证研究表明:经济发展战略下丰县镇村、农业、生态空间占比分别为18.51%、74.20%、7.29%,粮食安全战略下占比分别为16.07%、76.66%、7.27%,生态文明战略下占比分别为17.88%、69.06%、13.06%,权衡结果较合理。研究结论:国土空间权衡决策受国家战略驱动、以沟通为基础、以技术为手段,可有效解决国土空间用途冲突问题。  相似文献   
9.
World tourism cities perform multiple functions and exhibit various characteristics that influence tourism development within their boundaries. They are the main gateway for tourists visiting a country and their success has a direct impact on the visitor economy of that destination. London, the focus of this research, has been one of the world’s top tourism cities for many years, and a key gateway for domestic and international visitors. But despite the important role tourism plays in the economy of the city, there is limited research on the development of this activity in the capital. Using London as an exploratory case study, this paper contributes to better understanding the challenges faced by policy makers when planning and managing tourism in world cities. The adopted research method offers the advantage of gathering insightful information using multiple data collection techniques. Examining this new evidence contributes to expanding the knowledge on the particularities of tourism development in one of the top world cities, which could help policy makers in their efforts to better prepare for potential challenges faced by these complex but important destinations.  相似文献   
10.
The disproportionate concentration of healthcare professionals in urban areas is a concern in many countries, including Canada. A need to address this rural care gap has driven a large number of government led initiatives worldwide over the years. This paper presents a model that can be used as a tool to examine the efficacy of such policies on the workforce distribution in the long term. A small system dynamics model is employed to simulate the current and future distribution of general physicians at a jurisdictional level. The model represents the transition of general practitioners to provide insight into the dynamics of care provision over time. The movement, and competition, between rural and urban areas is modeled to enable detailed exploration of the ability for proposed measures to alleviate the care gap in the future. Among the tested policies are such commonly used initiatives as financial incentives to rural professionals, promotion of medical education in rural areas, expansion of rural education programs and the engagement of international medical graduates etc. We demonstrate how the model can be used as a tool to determine an efficient and well-chosen combination of policies which can help alleviate the rural care gap in the future, given that some policies are more effective than others alone but also combined with other initiatives. The presented small system dynamics model is tested on Canada's reality, but its simple nature lends itself to easy application to other countries that experience a similar problem.  相似文献   
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