全文获取类型
收费全文 | 233篇 |
免费 | 8篇 |
专业分类
管理学 | 36篇 |
民族学 | 1篇 |
人口学 | 22篇 |
理论方法论 | 18篇 |
综合类 | 2篇 |
社会学 | 64篇 |
统计学 | 98篇 |
出版年
2023年 | 5篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 9篇 |
2019年 | 18篇 |
2018年 | 16篇 |
2017年 | 21篇 |
2016年 | 14篇 |
2015年 | 10篇 |
2014年 | 8篇 |
2013年 | 51篇 |
2012年 | 7篇 |
2011年 | 9篇 |
2010年 | 7篇 |
2009年 | 1篇 |
2008年 | 2篇 |
2007年 | 7篇 |
2006年 | 8篇 |
2005年 | 5篇 |
2004年 | 2篇 |
2003年 | 6篇 |
2002年 | 2篇 |
2001年 | 2篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有241条查询结果,搜索用时 31 毫秒
81.
Many energy technologies that can provide reliable, low-carbon electricity generation are confined to nations that have access to robust technical and economic capabilities, either on their own or through geopolitical alliances. Equally important, these nations maintain a degree of institutional capacity that could lower the risks associated with deploying emergent energy technologies such as advanced nuclear or carbon capture and storage. The complexity, expense, and scrutiny that come with building these facilities make them infeasible choices for most nations. This paradigm is slowly changing, as the pressing need for low-carbon electricity generation and ongoing efforts to develop modular nuclear and carbon capture technologies have opened the door for potentially wider markets, including in nations without substantial institutional capacity. Here, using advanced nuclear technologies as our testbed, we develop new methods to evaluate national readiness for deploying complex energy infrastructure. Specifically, we use Data Envelopment Analysis—a method that eliminates the need for expert judgment—to benchmark performance across nations. We find that approximately 80% of new nuclear deployment occurs in nations that are in the top two quartiles of institutional and economic performance. However, 85% of potential low-carbon electricity demand growth is in nations that are in the bottom two quartiles of performance. We offer iconic paradigms for deploying nuclear power in each of these clusters of nations if the goal is to mitigate risk. Our research helps redouble efforts by industry, regulators, and international development agencies to focus on areas where readiness is low and risk correspondingly higher. 相似文献
82.
Consider a set of chemical products to be produced in a single facility. Each product has its own unique reaction time (which is assumed to be independent of its batch size), as well as other cost and demand values. In this paper, we address the problem of determining the optimal number of batches, batch sizes, and an accompanying production schedule for these products in the single facility that will minimize the total cost. Two different algorithms have been developed for this problem, the performances of which are contrasted with classical cyclic production schedules. Finally, some guidelines for the application of these methods to real-life problems are outlined. 相似文献
83.
In voting theory, analyzing the frequency of an event (e.g. a voting paradox), under some specific but widely used assumptions, is equivalent to computing the exact number of integer
solutions in a system of linear constraints. Recently, some algorithms for computing this number have been proposed in social
choice literature by Huang and Chua (Soc Choice Welfare 17:143–155 2000) and by Gehrlein (Soc Choice Welfare 19:503–512 2002;
Rev Econ Des 9:317–336 2006). The purpose of this paper is threefold. Firstly, we want to do justice to Eugène Ehrhart, who,
more than forty years ago, discovered the theoretical foundations of the above mentioned algorithms. Secondly, we present
some efficient algorithms that have been recently developed by computer scientists, independently from voting theorists. Thirdly,
we illustrate the use of these algorithms by providing some original results in voting theory.
Helpful comments by Philippe Clauss and his team are gratefully acknowledged. 相似文献
84.
This paper investigates the online hacking group, the Syrian Electronic Army (SEA), and examines its goals. The study argues that it is not a hacktivist group but is made up of cyber warriors who are closely connected to the Syrian government in order to serve two main goals: serving as a public relations tool for the Syrian government to draw the world's attention to the official Syrian version of events taking place in the country and countering the impact of Syrian oppositional groups. The study investigates the online reaction to SEA by analyzing the comments posted on its YouTube videos in order to better understand the group's aims and strategies and the public perception. 相似文献
85.
This article introduces a new generalization of the transmuted exponentiated modified Weibull distribution introduced by Eltehiwy and Ashour in 2013, using Kumaraswamy distribution introduced by Cordeiro and de Castro in 2011. We refer to the new distribution as Kumaraswamy-transmuted exponentiated modified Weibull (Kw-TEMW) distribution. The new model contains 54 lifetime distributions as special cases such as the KumaraswamyWeibull, exponentiated modified Weibull, exponentiated Weibull, exponentiated exponential, transmuted Weibull, Rayleigh, linear failure rate, and exponential distributions, among others. The properties of the new model are discussed and the maximum likelihood estimation is used to evaluate the parameters. Explicit expressions are derived for the moments and examine the order statistics. This model is capable of modeling various shapes of aging and failure criteria. 相似文献
86.
Most existing risk management models for process industries do not consider the effect of insurance coverage, which results in an overestimation of overall risk. A model is presented in this article to study the effect of insurance coverage of health, safety, environmental, and business risks. The effect of insurance recovery is modeled through the application of adjustment factors by considering the stochastic factors affecting insurance recovery. The insurance contract's conditions, deductibles, and policy limits are considered in developing the insurance recovery adjustment factors. Copula functions and Monte Carlo simulations are used to develop the distribution of the aggregate loss by considering the dependence among loss classes. A case study is used to demonstrate both the practical application of the proposed insurance model to improve management decisions, and the mitigating effect of insurance to minimize the residual risk. 相似文献
87.
Muhammad Zakaria Bashir Ahmed Fida Saquib Yousaf Janjua Syed Jawad Hussain Shahzad 《Social indicators research》2017,133(2):645-668
The paper empirically examines old-age security hypothesis to explain fertility rates in South Asia. Panel data is used for the period 1972–2013 for seven South Asian countries which include Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. The estimated results reveal that in South Asia fertility rate decreases with the increase in financial development. Thus, the findings support old-age security hypothesis that parents use children as financial instruments to secure their old age. This paper validates the theory that the availability of alternative financial tools reduces the incentives of households to have large offspring. Infant mortality is also shown an important factor for high fertility rate in South Asia. This implies that households cover their risk from losing children by producing more children. The results also reveal that fertility rate decreases with the increase in per capita income, which implies that households treat children as inferior good in this region. In other words, households prefer quality of children over quantity of children when their income level increases. The results have also shown that fertility decreases with the increase in education, urbanization, agriculture productivity and industrialization. The study has some important policy implications. 相似文献
88.
An asymptotic theory for the improved estimation of kurtosis parameter vector is developed for multi-sample case using uncertain prior information (UPI) that several kurtosis parameters are the same. Meta-analysis is performed to obtain pooled estimator, as it is a statistical methodology for pooling quantitative evidence. Pooled estimator is a good choice when assumption of homogeneity holds but it becomes inconsistent as assumption violates, therefore pretest and Stein-type shrinkage estimators are proposed as they combine sample and nonsample information in a superior way. Asymptotic properties of suggested estimators are discussed and their risk comparisons are also mentioned. 相似文献
89.
Guylaine Landry Christian Vandenberghe Ahmed Khalil Ben Ayed 《The Leadership Quarterly》2014,25(5):885-900
Using 322 matched employee–supervisor dyads, we investigate how level and direction of employee–supervisor (dis)agreement on supervisor's affective commitment to the employee relate to organizational commitment, emotional exhaustion, leader–member exchange, and job performance. Results from polynomial regression and response surface analyses indicate that level of employee–supervisor agreement matters: the most beneficial outcomes appear when supervisors and employees agree that the supervisor is highly committed to the employee whereas the least favorable outcomes appear when dyads' members agree that the supervisor has low commitment to the employee. Direction of employee–supervisor disagreement is also important as employee overestimation of supervisor commitment is associated with more favorable outcomes than employee underestimation. However, for two of the outcomes (organizational commitment and emotional exhaustion), the effect of employee–supervisor disagreement was attributable to a main effect of employee perceptions of supervisor commitment. We discuss the implications of these findings for the understanding of employee–supervisor relationships. 相似文献
90.
Abstract A group of 209 married, fecund women in rural Bangladesh were studied prospectively for 24 months from 1969 to 1971 to define some of the biological and sociological factors relating to fertility performance. These women were selected from a larger study population of 112,000 that had been followed with a daily house-to-house vital registration programme since 1966. The selected women were interviewed bi-weekly and were asked questions about menstruation, pregnancy, lactation, husband's occupational absences, and monthly urine tests for pregnancy were taken. The results for 193 non-contracepting women revealed that the seasonal pattern of births previously observed in this population could be associated with a corresponding seasonal pattern of conceptions and that this was due to a seasonal trend in fecundability. The highest conception rates were in the coolest months of the year. Post-partum lactational amenorrhoea was very prolonged, averaging 17 months for women with a surviving child. The appearance of the first post-partum menstrual flow (onset of ovulation) also had a seasonal trend which could not be adequately explained. The median waiting time to conception, once menstruation had resumed was eight months. This interval was influenced by seasonal fluctuations, as well as by the age of women and by husbands' absences. The foetal wastage rate was 15·0 per 100 conceptions, with 62 per cent of the foetal losses occurring during the second month of gestation. Overall, the average birth interval was 33 months, with the prolonged lactational amenorrhoea accounting for almost 45 per cent of this interval. From the Department of Population Dynamics, Johns Hopkins University, School of Hygiene and Public Health, Baltimore, Maryland 21205. 相似文献