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81.
The use of autonomous underwater vehicles (AUVs) for various applications have grown with maturing technology and improved accessibility. The deployment of AUVs for under-ice marine science research in the Antarctic is one such example. However, a higher risk of AUV loss is present during such endeavors due to the extremities in the Antarctic. A thorough analysis of risks is therefore crucial for formulating effective risk control policies and achieving a lower risk of loss. Existing risk analysis approaches focused predominantly on the technical aspects, as well as identifying static cause and effect relationships in the chain of events leading to AUV loss. Comparatively, the complex interrelationships between risk variables and other aspects of risk such as human errors have received much lesser attention. In this article, a systems-based risk analysis framework facilitated by system dynamics methodology is proposed to overcome existing shortfalls. To demonstrate usefulness of the framework, it is applied on an actual AUV program to examine the occurrence of human error during Antarctic deployment. Simulation of the resultant risk model showed an overall decline in human error incident rate with the increase in experience of the AUV team. Scenario analysis based on the example provided policy recommendations in areas of training, practice runs, recruitment policy, and setting of risk tolerance level. The proposed risk analysis framework is pragmatically useful for risk analysis of future AUV programs to ensure the sustainability of operations, facilitating both better control and monitoring of risk.  相似文献   
82.
Maintaining the performance of infrastructure-dependent systems in the face of surprises and unknowable risks is a grand challenge. Addressing this issue requires a better understanding of enabling conditions or principles that promote system resilience in a universal way. In this study, a set of such principles is interpreted as a group of interrelated conditions or organizational qualities that, taken together, engender system resilience. The field of resilience engineering identifies basic system or organizational qualities (e.g., abilities for learning) that are associated with enhanced general resilience and has packaged them into a set of principles that should be fostered. However, supporting conditions that give rise to such first-order system qualities remain elusive in the field. An integrative understanding of how such conditions co-occur and fit together to bring about resilience, therefore, has been less clear. This article contributes to addressing this gap by identifying a potentially more comprehensive set of principles for building general resilience in infrastructure-dependent systems. In approaching this aim, we organize scattered notions from across the literature. To reflect the partly self-organizing nature of infrastructure-dependent systems, we compare and synthesize two lines of research on resilience: resilience engineering and social-ecological system resilience. Although some of the principles discussed within the two fields overlap, there are some nuanced differences. By comparing and synthesizing the knowledge developed in them, we recommend an updated set of resilience-enhancing principles for infrastructure-dependent systems. In addition to proposing an expanded list of principles, we illustrate how these principles can co-occur and their interdependencies.  相似文献   
83.
This study sheds light on our understanding of when boards dismiss the CEO by considering the inherent conflict created by the board's advisory role when the firm underperforms. Using a sample of US firms listed in Standard & Poor's ExecuComp for the period 2000–2012 we find that, when a firm underperforms, extreme resource reallocation increases the likelihood of CEO dismissal. This relationship is positively moderated by the board's industry and CEO experience. The study contributes to the literature on corporate governance by identifying the conditions that trigger dismissal of the CEO in light of boards’ motive to protect their reputation.  相似文献   
84.
The rise of the corporate profession has contributed to a more varied and ambiguous professional terrain that is increasingly seen to be indeterminate and fluid. This paper advances the current debate around the development of corporate professions, exploring how practitioners respond to this environment. Drawing on research with public relations practitioners, the paper shows how the idea of being a liminar facilitates the formation of a professional identity in conditions of high indeterminacy. In taking an individual level of analysis of professions, the paper suggests that indeterminacy is a more resonant feature for corporate professionals than previously suggested in the research, but that this indeterminacy is navigated in professional identity construction through ‘being a liminar’, and thus greater nuance may need to be recognized in the conceptualization of both corporate professions and corporate professionalization. It also demonstrates the use of liminality as a discursive resource in identity construction and with it, challenges the common association of liminality with self‐doubt and existential anxiety. In turn, the paper considers the implications of the liminal professional identity for the future of contemporary professions, and for understanding the liminal experience.  相似文献   
85.
In this paper, we predict that venture capital (VC) backed initial public offerings (IPOs) will attract more attention than non-VC-backed IPOs, as VCs offer important signals to investors searching for information about entrepreneurial firms. We use a measure developed by Google (i.e., Trends) to capture the spikes in investors' attention experienced by firms in the time period surrounding their IPOs. Our results demonstrate that firms backed by VCs enjoy a far greater spike in attention than their counterparts. Furthermore, we find that firms with more prominent VCs, a larger number of VCs, and VCs situated at farther geographic distances exhibit significantly greater spikes in investors’ attention during the week of their IPO. Combined, the findings show a clear demarcation between entrepreneurial firms with or without VC backing, they bring to the fore new upshots stemming from the relationship between VCs and entrepreneurial firms, and they raise new potential questions on this relationship and beyond.  相似文献   
86.
Building on recent efforts to bring a socio-political perspective to social capital research, we develop and test a multilevel framework that explains why middle managers who occupy brokerage positions differ in their ability and willingness to engage in entrepreneurial behavior. More specifically, we provide a contextualized understanding of the links among middle managers' brokerage, their political-support ties, and their personal initiative. Results derived from data on 383 middle managers and 72 top managers in 34 business units indicate that political-support ties with top managers strengthen the relationship between middle managers’ brokerage and personal initiative. However, this positive effect depends on the social capital resources available in the focal business unit. It is attenuated in business units with a supportive and trusting social context and amplified in business units with high levels of internal connectedness. By uncovering these incompatibilities and complementarities, our study demonstrates the value of accounting for different social capital configurations and the interplay of their inherent social capital resources when examining the effects of brokerage on corporate entrepreneurship.  相似文献   
87.
Research on firm search stresses the need for firms to adapt and align concurrently with their environment to optimize the ability to sense and seize opportunities for sustained performance. We postulate resource scarcity as an important contingency factor for the search-performance relationship, and assess its joint influence with high and low dynamism. Using a dataset spanning 23 years, we examine the performance implications of combinations of internal and external exploratory and exploitative search in resource-scarce environments, under conditions of high and low dynamism. We find that resource scarcity is an important condition for performance stemming from exploratory and exploitative search: even under conditions that involve low dynamism, but joined with resource scarcity, firms may benefit from pursuing exploratory and exploitative knowledge simultaneously.  相似文献   
88.
文章有两个目的,其一是为中国学者介绍经过语义化的英语语气系统网络,其二是说明以新的语气系统网络替代之前旧的语气系统网络的重要性。文章的前半部分,即一至四章,通过介绍本文的研究方向,回答关于语气系统的三个问题,回顾早期对语气系统的语义化描述,并阐释影响语气系统语义化进程的因素,从而说明第二个目的。第一个目的由较长的第五章实现,它和附录一起构成了文章的后半部分,着重呈现了一个全新的经过语义化的语气系统网络。   相似文献   
89.
Urbanized areas show a high proportion of non-native plants and can work as dispersal points to the surrounding areas. Ensenada is a fast growing city located in the northwestern peninsula of Baja California (Mexico). It is the southern extreme of a bi-national, coastal urban corridor that extends from Los Angeles, California south to Ensenada. This corridor is part of the biodiversity hotspot of the California Floristic Province. The aim of this study was to analyze the composition and distribution of the spontaneous flora in the city of Ensenada. We systematically sampled two differentiated urban environments, vacant lots and arroyos, in 2006 and 2007. We found a total of 158 plant species, 61% of them were non-native species. Arroyo areas showed higher non-native species richness than vacant lots (21.9 vs. 13.6 species/transect) and could be potential dispersal vectors for non-native species to natural areas outside of the city, or in the reverse direction also.  相似文献   
90.
The attempt to give children an effective voice in social work processes which can have substantial impact on their lives takes different forms in countries with varying professional cultures and legal frameworks. This paper reports on a study of children's participation in decision-making in care and protection services in Norway, which was carried out in conjunction with a project to support social work teams in enabling children to participate, using materials borrowed from England and Wales. The results showed that (a) taking an active part in decision-making did not correlate perfectly with (b) having an influence on the outcome. Cases were therefore classified as ‘participation’ or ‘non-participation’ using a combination of both the above criteria. Statistical analysis of the factors influencing children's participation enabled the proposition of a model which appeared to explain much of the variance. The results point to the inadequacy of equating social work conversation with children with effective participation in decision-making.  相似文献   
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