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1.
The objective of this paper is twofold. First, it develops a prediction system to help the credit card issuer model the credit card delinquency risk. Second, it seeks to explore the potential of deep learning (also called a deep neural network), an emerging artificial intelligence technology, in the credit risk domain. With real-life credit card data linked to 711,397 credit card holders from a large bank in Brazil, this study develops a deep neural network to evaluate the risk of credit card delinquency based on the client's personal characteristics and the spending behaviours. Compared with machine-learning algorithms of logistic regression, naive Bayes, traditional artificial neural networks, and decision trees, deep neural networks have a better overall predictive performance with the highest F scores and area under the receiver operating characteristic curve. The successful application of deep learning implies that artificial intelligence has great potential to support and automate credit risk assessment for financial institutions and credit bureaus.  相似文献   
2.
Bureaucracies are usually regarded as inefficient, wasteful mechanisms. Contrary to this deeply rooted perception of bureaucracy, this paper documents the case of the correctional authorities in Washington State, a bureaucracy that acted with a considerable degree of innovation and professionalism. Their task was to administer a risk assessment instrument that measured the level of risk posed by offenders by way of a numerical score. They used that score to identify the level of supervision offenders were to receive once released into the community. In analyzing the data, I discovered an unusual application of the instrument that resulted in many offenders being bumped to a higher supervision level. Using a regression discontinuity design, I uncover the mechanics of the bumping-up process and I generate an instrument that is cleansed of the manipulation. I find that the manipulated instrument predicts serious recidivism events better than the cleansed instrument, especially when these events involve high-risk offenders, thus providing evidence that the authorities had good reason to undertake the manipulation.  相似文献   
3.
Popular teamwork assessments have been strongly criticized on the grounds of poor psychometric properties and their disconnect with conceptual models of teamwork. These issues raise concerns with respect to our ability to evaluate efforts devoted to advancing teamwork in academia. We report the development of a teamwork assessment that builds on empirically supported conceptualizations of team processes. Two studies were conducted to test and to cross-validate the psychometrics of the resulting measure. In the discussion section, we address the implications of our findings for conceptual models of teamwork and provide guidelines for using the measure in business education.  相似文献   
4.
为调查南充市米粉中重金属污染物情况,评价食用米粉摄入重金属对消费者的健康危害,采集南充市辖区不同类型、不同来源米粉样品200个,采用国家标准方法对米粉中5种重金属进行检测。结果表明:米粉中铅超标率为1.00%,镉超标率为0.5%,铬超标率为2.00%,砷、汞未超标,米粉中重金属综合污染指数为0.380,污染程度为安全,米粉综合健康危害指数为0.562,南充市米粉中重金属总体处于安全范围,不会对食用者造成健康危害。  相似文献   
5.
Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

6.
《中国林业经济》2021,(3):105-108
我国银行衍生产品体系是银行业重要的体系之一。通过我国期货交易细则、期权市场交易额等相关信息及数据的搜集,并将数据进行趋势化分析,从而对我国银行衍生产品体系的发展特点和问题进行研究,研究发现:我国银行衍生产品体系具有法律规范体系初步完善、风险评估体系国际化、衍生品市场发展迅猛等发展特点,但存在衍生品市场缺乏市场竞争力、不适应政策变化、不能自主定价等问题,提出了建立信息明确有序的交易体系、增强竞争力争取定价权益等建议。  相似文献   
7.
This paper examines the environmental sustainability practices of multinational mining companies in addressing their impacts and promoting the sustainable development of local communities in Ghana. Although large-scale mining companies have embraced environmental sustainability, the drivers and the mechanisms for addressing their impacts throughout the mine life cycle is not fully understood because of the limited research in this area. The focus in this study involves an examination of the drivers for environmental sustainability in a weak and non-enabling institutional context and the mechanisms for addressing impacts on biodiversity, water quality and quantity, and ambient climate. The findings show that the environmental sustainability practices of multinational mining companies are determined by regulatory compliance and corporate environmental responsibility based on perceived ethical obligation. Additionally, we find gaps in mine closure planning and rehabilitation because of the limited requirement for biodiversity restoration in the domains of flora repopulation and active fauna reintroduction. This paper provides empirical and theoretical insights for academics and practitioners in industry and policymaking.  相似文献   
8.
王利军  刘伟  吴雨航  宋楠  申晶 《科技和产业》2021,21(12):299-306
为提升挂篮施工风险评估的科学性,实现施工现场风险评估的智能化,提出基于直觉模糊层次分析法与灰云模型相结合的挂篮施工风险评估模型,并使用Python语言开发挂篮施工风险评估软件。首先,从挂篮拼装预压、混凝土工程、预应力工程、挂篮行走、挂篮拆除等5个方面建立风险评估指标体系,识别潜在风险因素;其次,运用直觉模糊层次分析法对指标进行赋权。同时,运用云理论改进灰色聚类模型的白化权函数,使其能够有效反映评估指标的模糊性与不确定性;最后,基于Python语言,开发出挂篮施工风险评估软件,用此软件对西郊大桥挂篮施工进行风险评估,验证模型的准确性。提供了一套完整的挂篮施工风险评估系统,可为决策者规避风险提供参考。  相似文献   
9.
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   
10.
[目的]通过"五结合"生态温室生命周期评价及比较分析,发现各类温室潜在的环境影响及其关键要素,探索各模式改进提升的重点及未来发展方向。[方法]应用生命周期评价方法,将"五结合"生态温室与国内典型地区节能日光温室和国外同类模式进行环境综合评价,在此基础上分析"五结合"生态温室替代常规模式的可能性。[结果]较节能日光温室,生态温室单位产品的能源消耗、水资源消耗、气候变化、潜在的环境酸化、富营养化、人体、水体和土壤毒性分别降低了27%, 64%, 27%, 32%, 43%, 97%, 99%和99%,综合环境指数降低98.6%,环境效益大幅度提升。与国外同类模式相比,由于充分利用太阳能,中国常规模式在降低能源消耗和温室气体减排方面优势明显,其他各项环境指数与国外相比还存在较大差距,但"五结合"生态温室各项指数全面优于或接近国外同类模式。[结论]以"五结合"生态温室为代表的生态模式能够解决国内外温室发展面临的众多瓶颈问题,具有极大的发展潜力和应用价值。  相似文献   
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