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41.
This article traces the representations of ethnicity and immigration in mainstream American and Canadian archives since the 1950s. It identifies three main periods of evolution of these ethnic archives: the era prior to the civil rights movement, the 1960–1980s and the 1990s and beyond. Relying on an understanding of archival collections as social constructions anchored in specific historical contexts, the article considers the various political, economic, social and technological factors that affected ethnic archives over time, especially as they relate to changing scholarly and popular conceptions of ethnicity in North America. It pays particular attention to the impact of historical scholarship in fields related to immigration and ethnicity and of postmodernist archival theories that challenge the traditional view of archives as evidence of the past. It suggests that the relationship between ethnic archives and their historical context is dialectical: not only are they affected by the context in which they are developed and managed, but they also have an impact on that context as they favor certain conceptions of ethnicity and types of ethnic groups at the expense of others. Both curators and users of archival materials should therefore pay closer attention to the history of the processes that went into the construction of these archives to avoid falling victims to the illusion of ethnic authenticity.  相似文献   
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This paper presents a trajectory-based online control reconfiguration mechanism against unknown fault occurring in an electric circuit. First, we demonstrate the modeling of an electric circuit by taking the time-trajectory viewpoint, where no a priori input–output partition has been made. The uniqueness of this viewpoint lies in the fact that it deals only with variables that describe the system without any dedicated (external or internal -type) representation. Subsequently, we illustrate a novel real-time fault-tolerant control (FTC) strategy based on this trajectory standpoint, which does not require an explicit model-based fault diagnosis unit. Instead, the controller is reconfigured directly based on the trajectories generated by the system in real-time, and the given control specifications. In this way, we efficiently excrete the shortcomings that are often seen in model-based fault-tolerant systems. The proposed FTC method is effectively demonstrated on an RLC circuit.  相似文献   
43.
We analyse how the impact of determinants of inter-firm knowledge transfers in alliances can be moderated by the proximity of the resources pooled by partners. Six factors are examined: relative absorptive capacity (RAC), inter-partner trust, cultural distance between allies, knowledge ambiguity, knowledge protection, and the partners’ learning intent. We distinguish alliances mobilizing similar resources by partners (called ‘endogamies’ as allies build on their similarities) from alliances pooling different resources (called ‘exogamies’ as allies build on their differences). We propose that: (a) the impact of RAC on knowledge transfers is reinforced in exogamies, but reduced in endogamies; (b) the knowledge ambiguity and cultural distance effect is less in endogamies than in exogamies; (c) the trust and knowledge protection impact is stronger in exogamies than in endogamies; (d) the learning intent impact on knowledge transfers is similar in endogamies and exogamies.  相似文献   
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Patent systems for encouraging innovation: Lessons from economic analysis   总被引:2,自引:0,他引:2  
Economic theory views patents as policy instruments aimed at fostering innovation and diffusion. Three major implications are drawn regarding current policy debates. First, patents may not be the most effective means of protection for inventors to recover R&D investments when imitation is costly and first mover advantages are important. Second, patentability requirements, such as novelty or non-obviousness, should be sufficiently stringent to avoid the grant of patents for inventions with low social value that increase the social cost of the patent system. Third, the trade-off between the patent policy instruments of length and breadth could be used to provide sufficient incentives to develop inventions with high social value. Beyond these three implications, economic theory also pleads for a mechanism design approach: an optimal patent system could be based on a menu of different degrees of patent protection where stronger protection would involve higher fees, allowing self-selection by inventors.  相似文献   
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Children need to learn to persist through challenges, yet adults sometimes step in to solve problems for them. Here, we looked at how adult taking over related to children’s persistence. In an observational study (N = 34, ages 4–8), we found that parents who took over more often during a challenging puzzle task rated their children as dispositionally less persistent. To establish whether taking over can cause reduced persistence, we ran two preregistered experiments (N = 150, ages 4–5). Children assigned to a taking over condition persisted less on a subsequent task compared to those in a teaching or a baseline condition. Reframing the context did not ameliorate the negative impact of taking over. The results suggest that taking over impairs children’s persistence.  相似文献   
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OBJECTIVE: The aim of this study is to identify the distinct developmental experiences associated with child sexual abuse and rape. METHOD: For 269 sexual offenders (137 rapists and 132 child sexual abusers), developmental experiences were recorded from a behavioral checklist, a parental-bonding survey, and a sexual history questionnaire. Offender classification was obtained from official records and verified through polygraph examinations. RESULTS: Compared to rapists, child sexual abusers reported more frequent experiences of child sexual abuse (73%), early exposure to pornography (65% before age 10), an earlier onset of masturbation (60% before age 11), and sexual activities with animals (38%). In contrast to child sexual abusers, rapists reported more frequent experiences of physical abuse (68%), parental violence (78%), emotional abuse (70%), and cruelty to animals (68%). Both child sexual abusers and rapists (>93%) reported frequent exposure to violent media during their childhood. Most offenders (94%) described having insecure parental attachment bonds; 76% of rapists reported avoidant parental attachments and 62% of child sexual abusers reported anxious parental attachments. CONCLUSIONS: Findings from this study support the role of specific developmental experiences as etiological factors in differential sexual offending. Child sexual abusers' developmental histories were characterized by heightened sexuality; whereas rapists' childhood histories were more indicative of violence. These findings have implications for the treatment of sexual abusers and the prevention of sexual abuse. PRACTICE IMPLICATIONS: This study's findings suggest that sexual offenders have been socialized to satisfy human needs of intimacy and sexuality through maladaptive means, which implies that a risk management approach may not be sufficient treatment. Although risk models teach offenders skills to avoid high-risk situations, they fail to address the maladaptive strategies that they may have developed for satisfying needs. Instead, the focus of treatment should be to equip offenders with the knowledge, skills, and opportunities to achieve these needs in an acceptable manner. Thus, this model will provide these individuals with the opportunity to live a healthy life without sexual offending.  相似文献   
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Based on a survey of the inventors of 9017 European patented inventions, this paper provides new information about the characteristics of European inventors, the sources of their knowledge, the importance of formal and informal collaborations, the motivations to invent, and the actual use and economic value of the patents.  相似文献   
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