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991.
In this article, an agent‐based framework to quantify the seismic resilience of an electric power supply system (EPSS) and the community it serves is presented. Within the framework, the loss and restoration of the EPSS power generation and delivery capacity and of the power demand from the served community are used to assess the electric power deficit during the damage absorption and recovery processes. Damage to the components of the EPSS and of the community‐built environment is evaluated using the seismic fragility functions. The restoration of the community electric power demand is evaluated using the seismic recovery functions. However, the postearthquake EPSS recovery process is modeled using an agent‐based model with two agents, the EPSS Operator and the Community Administrator. The resilience of the EPSS–community system is quantified using direct, EPSS‐related, societal, and community‐related indicators. Parametric studies are carried out to quantify the influence of different seismic hazard scenarios, agent characteristics, and power dispatch strategies on the EPSS–community seismic resilience. The use of the agent‐based modeling framework enabled a rational formulation of the postearthquake recovery phase and highlighted the interaction between the EPSS and the community in the recovery process not quantified in resilience models developed to date. Furthermore, it shows that the resilience of different community sectors can be enhanced by different power dispatch strategies. The proposed agent‐based EPSS–community system resilience quantification framework can be used to develop better community and infrastructure system risk governance policies. 相似文献
992.
993.
Housing recovery is an unequal and complex process presumed to occur in four stages: emergency shelter, temporary shelter, temporary housing, and permanent housing. This work questions the four-stage typology and examines how different types of shelter align with multiple housing recovery stages given different levels of social vulnerability. This article also presents a Markov chain model of the postdisaster housing recovery process that focuses on the experience of the household. The model predicts the sequence and timing of a household going through housing recovery, capturing households that end in either permanent housing or a fifth possible stage of failure. The probability of a household transitioning through the stages is computed using a transition probability matrix (TPM). The TPM is assembled using proposed transition probability models that vary with the social vulnerability of the household. Monte Carlo techniques are applied to demonstrate the range of sequences and timing that households experience going through the housing recovery process. A set of computational rules are established for sending a household to the fifth stage, representing a household languishing in unstable housing. This predictive model is exemplified on a virtual community, Centerville, where following a severe earthquake scenario, differences in housing recovery times exceed four years. The Centerville analysis results in nearly 5% of households languishing in unstable housing, thereby failing to reach housing recovery. These findings highlight the disparate trajectories experienced by households with different levels of social vulnerability. Recommendations are provided at the end for more equitable postdisaster recovery policies. 相似文献
994.
在以人道主义为本的应急救援活动中,不可忽视被救灾民和施救决策者们异质性行为的影响。一方面,将各灾民因救援物资需求未被及时满足而呈现的差异化心理痛苦度量成经济损失,并纳入应急救援调度的社会成本这一决策目标中;另一方面,在灾后物资调度决策中,关注具有异质性偏好的各应急决策者所展现出的不同救援态度。结合面向联合机会约束规划的动态供需平衡限制,最终构建一个考虑灾民和决策者们异质性行为的多阶段灾后救援物资分配和应急路径优化模型。采用2008年汶川地震为案例背景,应用遗传算法对模型求解和参数分析,将仿真结果与不考虑异质性行为的传统救援调度方案进行比较,得出一些结论为构建高效的应急救援体系提供有益参考。 相似文献
995.
996.
Mark J. Kaiser 《Risk analysis》2015,35(8):1562-1590
Public companies in the United States are required to report standardized values of their proved reserves and asset retirement obligations on an annual basis. When compared, these two measures provide an aggregate indicator of corporate decommissioning risk but, because of their consolidated nature, cannot readily be decomposed at a more granular level. The purpose of this article is to introduce a decommissioning risk metric defined in terms of the ratio of the expected value of an asset's reserves to its expected cost of decommissioning. Asset decommissioning risk (ADR) is more difficult to compute than a consolidated corporate risk measure, but can be used to quantify the decommissioning risk of structures and to perform regional comparisons, and also provides market signals of future decommissioning activity. We formalize two risk metrics for decommissioning and apply the ADR metric to the deepwater Gulf of Mexico (GOM) floater inventory. Deepwater oil and gas structures are expensive to construct, and at the end of their useful life, will be expensive to decommission. The value of proved reserves for the 42 floating structures in the GOM circa January 2013 is estimated to range between $37 and $80 billion for future oil prices between 60 and 120 $/bbl, which is about 10 to 20 times greater than the estimated $4.3 billion to decommission the inventory. Eni's Allegheny and MC Offshore's Jolliet tension leg platforms have ADR metrics less than one and are approaching the end of their useful life. Application of the proposed metrics in the regulatory review of supplemental bonding requirements in the U.S. Outer Continental Shelf is suggested to complement the current suite of financial metrics employed. 相似文献
997.
何跞 《内蒙古民族大学学报(社会科学版)》2016,(4):98-102
元代江西诗人刘诜的五言古诗成就斐然,诗中多涉及现实题材与日常生活,表现出庐陵诗人的求实性格和讲求真性情的特点。刘诜诗中对时事民生的关注,笔法古雅沉劲。而对日常生活的书写,则多体现出乐观自适的生活态度,又呈现出自然清和的诗歌风格。 相似文献
998.
Igor Yakovenko David C. Hodgins Nady el-Guebaly David M. Casey Shawn R. Currie Garry J. Smith 《International Gambling Studies》2016,16(2):175-192
Disordered gambling is best conceptualized as a continuum of severity. Previous research has demonstrated the utility of studying individuals at all points of this spectrum. The sequence of the development of gambling problems and change in gambling involvement along this continuum of severity is not well understood. The present study examined the interplay between cognitive distortions and gambling involvement in a population sample recruited in Alberta, Canada. Data from 1372 participants over 4 assessment waves (5 years) were used to generate a 2-factor latent structure using gambling fallacies and gambling involvement measurements. Structural equation modelling showed that cognitive distortions more strongly predicted future gambling involvement than the reverse relationship, using the comparative fit index (CFI) and the root mean square error of approximation (RMSEA) to assess the models. In addition, cognitive distortions declined over time, whereas gambling involvement remained stable. The results of the study suggest that focusing primarily on cognitive mechanisms in public health initiatives for gambling disorders may be a more effective strategy than focusing on behavioural solutions. 相似文献
999.
1000.
There is a broad academic discussion about the impact of funding grants from a foundation or a government department on individual support intentions toward the nonprofit organization receiving the grant. However, the role of the grant provider's reputation has frequently been overlooked. In this study, we experimentally tested whether there is a reputation spillover effect of a grant‐providing organization. Based on a real‐life example, we asked citizens to rate their willingness to donate to a nonprofit organization, and we experimentally manipulated the available information on funding sources. We test this for both a government department and a foundation as a grant provider. Our results suggest that not the act of receiving a grant, but the citizens' awareness about the funding organization—at least in the case of a foundation—has an impact on support intentions. In contrast, for a prominent government department as a grant provider, we did not find support for a reputation spillover effect. 相似文献