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11.
Rossella Cappetta Author Vitae Paola Cillo Author Vitae Anna Ponti Author Vitae 《Research Policy》2006,35(9):1273-1290
In this paper we propose and test an evolutionary model of stylistic innovation, that is the change in the aesthetic and symbolic elements of products and services. Style is an increasingly relevant phenomenon in many industries and our goal is to develop a model of how styles get introduced and adopted. We build on existent literature on technological change to frame the dynamics of how style changes across time. In the model we propose, companies face periods of ferment with relevant stylistic variations and periods of convergence on a single trend—that is the stylistic convergent design versus the technologic dominant design. We identify the drivers of convergence in stylistic innovation. We test the model with a longitudinal empirical study (1984-2002) in the fine fashion industry, explaining the main differences between a stylistic and a technological evolutionary model. 相似文献
12.
Janice Taylor GordonAuthor Vitae 《Journal of The Franklin Institute》2002,339(3):321-333
The Franklin Institute, Philadelphia, Pennsylvania awarded the 2001 Benjamin Franklin Medal in Life Science to Judah Folkman for his founding of the field of angiogenesis research and demonstration that angiogenesis is a necessary factor in the conversion of abnormal cells to malignant tumors. 相似文献
13.
Jaymee R. Shell Shawn M. K. Robbins Philippe C. Dixon Philippe J. Renaud René A. Turcotte Tom Wu 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):313-324
The forward skating start is a fundamental skill for male and female ice hockey players. However, performance differences by athlete’s sex cannot be fully explained by physiological variables; hence, other factors such as skating technique warrant examination. Therefore, the purpose of this study was to evaluate the body movement kinematics of ice hockey skating starts between elite male and female ice hockey participants. Male (n = 9) and female (n = 10) elite ice hockey players performed five forward skating start accelerations. An 18-camera motion capture system placed on the arena ice surface captured full-body kinematics during the first seven skating start steps within 15 meters. Males’ maximum skating speeds were greater than females. Skating technique sex differences were noted: in particular, females presented ~10° lower hip abduction throughout skating stance as well as ~10° greater knee extension at initial ice stance contact, conspicuously followed by a brief cessation in knee extension at the moment of ice contact, not evident in male skaters. Further study is warranted to explain why these skating technique differences exist in relation to factors such as differences in training, equipment, performance level, and anthropometrics. 相似文献
14.
15.
In recent years, there has been rapid growth in the volume of research output on the topic of e-government. To understand this research better, we used content analysis of eighty-four papers in e-government-specific research outlets (two journals and one conference series). Our analytical focus took in five main aspects: perspectives on the impacts of e-government, research philosophy, use of theory, methodology and method, and practical recommendations. Normative evaluation identified some positive features, such as recognition of contextual factors beyond technology, and a diversity of referent domains and ideas. Alongside this, though, research draws mainly from a weak or confused positivism and is dominated by over-optimistic, a-theoretical work that has done little to accumulate either knowledge or practical guidance for e-government. Worse, there is a lack of clarity and lack of rigor about research methods alongside poor treatment of generalization. We suggest ways of strengthening e-government research but also draw out some deeper issues, such as the role of research philosophy and theory, and the institutional factors – particularly pressures of competition and time – that may constrain development of e-government as a research field. 相似文献
16.
Phyllis Bernt Lawrence WoodAuthor VitaeCarol TingAuthor Vitae 《Government Information Quarterly》2007
The role and continued relevance of state telecommunications regulators have been challenged by the development of competition, the introduction of new technologies, and the increasing dominance of federal authority. An important role that state utility commissions can play in the current telecommunications environment is to provide consumer education and information about consumer protection, competition, and universal service. Commissions can use their Web sites as effective tools in educating and informing consumers. This study analyzes the consumer-related telecommunications information included on the Web sites of the commissions in the 50 states and the District of Columbia to determine whether, and how well, state commissions are using their Web sites to educate and inform. 相似文献
17.
Until recently, the traditional Inverted-U hypothesis had been the primary model used by sport psychologists to describe the arousal-performance relationship. However, many sport psychology researchers have challenged this relationship, and the current trend is a shift toward a more "multidimensional" view of arousal-anxiety and its effects on performance. In the current study, 104 college-age participants performed a simple response time task while riding a bicycle ergometer. Participants were randomly assigned to one of eight arousal groups (between 20 and 90% of heart rate reserve) and were told they were competing for a cash prize. Prior to the task, the Competitive State Anxiety Inventory-2 and Sport Anxiety Scale (SAS) were administered to assess the influence of cognitive and somatic anxiety. As hypothesized, regression analysis revealed a significant quadratic trend for arousal and reaction time. This accounted for 13.2% of the variance, F change (1, 101) = 15.10, p < .001, in performance beyond that accounted for by the nonsignificant linear trend. As predicted by the Inverted-U hypothesis, optimal performance on the simple task was seen at 60 and 70% of maximum arousal. Furthermore, for the simple task used in this study, only somatic anxiety as measured by the SAS accounted for significant variance in performance beyond that accounted for by arousal alone. These findings support predictions of the Inverted-U hypothesis and raise doubts about the utility theories that rely on differentiation of cognitive and somatic anxiety to predict performance on simple tasks that are not cognitively loaded. 相似文献
18.
Ashleigh M. Day Sydney O’Shay-Wallace Matthew W. Seeger Shawn P. McElmurry 《Communication Studies》2019,70(3):352-376
Safe, clean water is necessary for health and well-being. Water issues affect minority and vulnerable populations at disproportionate rates, including the poor and racial and ethnic minorities. An investigation of the relationships of race, social media use, and informational sources during the municipal water crisis in Flint, Michigan, reflects an instrumental view of communication and uses and gratifications theory in this study. Data from 208 Flint residents in 2016 indicated that African American respondents favored interpersonal networks and resources and were more likely than other racial groups to obtain current information about the water crisis via Instagram. Preferred channels and sources to receive additional crisis information varied on the basis of race. 相似文献
19.
Appreciation of problem structure is critical to successful learning. Two experiments investigated effective ways of communicating problem structure in a computer-based learning environment and tested whether verbal instruction is necessary to specify solution steps, when deep structure is already embellished by instructional examples. Participants learned to solve algebra-like problems and then solved transfer problems that required adjustment of learned procedures. Experiment 1 demonstrated that verbal instruction helped learning by reducing learners' floundering, but its positive effect disappeared in the transfer. More importantly, students transferred better when they studied with examples that emphasized problem structure rather than solution procedure. Experiment 2 showed that verbal instruction was not necessarily more effective than nonverbal scaffolding to convey problem structure. Final understanding was determined by transparency of problem structure regardless of presence of verbal instruction. However, verbal instruction had a positive impact on learners by having them persist through the task, and optimal instructional choices were likely to differ depending on populations of learners. 相似文献
20.
Kenneth P. KodamaAuthor Vitae 《Journal of The Franklin Institute》2002,339(3):315-320
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2001 Benjamin Franklin Medal in Earth Science to Rob Van der Voo for his outstanding contributions to the field of paleomagnetism and his reconstruction of ancient continental positions that have lead to a better understanding of plate tectonic processes for the past billion years of Earth history. 相似文献