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61.
The goals of this study were to investigate the timing and the mechanism by which two types of model-centered instruction
(MCI)—expert modeling (EM) and self-guided modeling (SGM)—might be made increasingly effective, efficient, and engaging for
learners with different levels of expertise. The 62 pre-service and in-service evaluators who participated in the study were
randomly assigned to one of these two types of MCI. The participants in the EM group were provided with the conceptual models
used by experts to solve ethical conflicts within program evaluation. The participants in SGM group received no guidance in
developing their own mental models. Regarding instructional effectiveness measures, there were no significant differences
between the two types of MCI. However, inexperienced learners in the EM group invested less instructional effort and time
than did those in the SGM group. In addition, inexperienced learners in the EM group also exhibited more engagement than did
those in the SGM group. Therefore, EM is likely to be the more appropriate instructional design for inexperienced learners.
Expert modeling required experienced learners to invest more mental effort, because if the conceptual model of the expert
was redundant, it required them to integrate the previous schema with resulting overload of their working memory. Regardless
of the types of MCI employed, the inexperienced participants showed significantly higher levels of attention and satisfaction
than did the experienced participants. 相似文献
62.
63.
Michael O'Connor Angus Macfarlane 《International journal for the advancement of counseling》2002,24(4):223-237
Maori stories and symbols offer Westerns counselors a rich heritageof wisdom. This article provides a summary of key Maori mythologyand worldview highlighting the profound significance of sacredgeography—manifested in the marae (meeting ground) andthe wharenui (meeting house)—and family (whenau) imbedded in genealogy (whakapa). The authors then considerrelated significance for contemporary Maori, offer questions andapplications for western counsellors, and acknowledge essentialconsultation from a Maori staff advisor (te kaiurungi). 相似文献
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Elsie L. Echeverri-Carroll Michael D. Oden David V. Gibson Evan A. Johnston 《Research Policy》2018,47(1):209-217
There has been considerable media coverage highlighting the lack of gender diversity in Silicon Valley, stressing the relatively low participation of women in the high-tech economy. Austin offers a unique case for testing whether similar gender issues characterized other high-tech regions because the city has historically benefited from the expansion of Silicon Valley’s large high-tech firms since the 1980s. The gender-biased business practices identified in Silicon Valley firms may have been transferred to their branch plants in Austin. Our analysis shows women’s losses in middle-skill occupation employment shares were concentrated in the low-tech industry and were partially offset by job share gains in high-skill occupations in the same sector between 1980 and 2015. Men’s losses in middle-skill occupation job share were also mainly concentrated in the low-tech sector but were partially offset by employment share gains in high-skill occupations only in the high-tech industry during this period. Women made large gains in relative real median wages only in high-skill occupations in the high-tech industry while their relative real median wages in other skill occupations and in the low-tech industry stagnated around zero during this period. Men’s gains in relative median wages were also concentrated only in the high-tech industry but were less than half of women’s and were negative (between ?10 and ?21 percent) in other occupations in the high-tech industry and across all occupations in the low-tech industry. As noted in previous studies, the impact of job polarization is not well understood across sectors and gender. This study finds the high-tech industry in Austin has had unintended consequences in terms of job polarization across gender, providing relatively fewer job opportunities in high-skill occupations to women than men but offering much higher gains in relative real median wages to women than men. Males also found relatively more job opportunities in high-skill occupations in the high-tech industry than women but experienced only half of women’s gains in relative median wages in this industry between 1980 and 2015. 相似文献
66.
In a study of 243 firms of varying sizes across 14 different industries, we investigate the effect of customer participation on new product development performance. We confirm that overall customer participation is positively related to new product development performance and that the effect is mediated by innovativeness. We also demonstrate that these effects are contingent upon absorptive capacity of the firm in question such that firms with high absorptive capacity stand to gain more from engaging their customers in new product development than firms with low absorptive capacity, especially at the later stages of the NPD process. The results are robust to alternative estimation techniques, measures employed to operationalize key concepts, and the industrial makeup of the sample. Post hoc analyses provide non-trivial managerial implications for the decision makers at the firm level. 相似文献
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68.
Salmanzadeh A Kittur H Sano MB C Roberts P Schmelz EM Davalos RV 《Biomicrofluidics》2012,6(2):24104-2410413
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool. 相似文献
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70.
Dylan Poulsen Michael Defoort Mohamed Djemai 《Journal of The Franklin Institute》2019,356(16):9076-9094
We consider the leader–follower consensus problem for a multi-agent system where information is exchanged only on a non-uniform discrete stochastic time domain. For a second-order multi-agent system subject to intermittent information exchange, we model the tracking error dynamics as a varying linear system on a discrete stochastic time scale, where μ is the graininess operator. Based on a Lyapunov operator and a positive perturbation operator on the space of symmetric matrices, we derive necessary and sufficient conditions to design a decentralized consensus protocol. This protocol allows us to cast the mean-square exponential consensus problem within the framework of dynamic equations on stochastic time scales. We establish some theoretical results which allow for the computation of the control gain matrix which guarantees the mean-square exponential stability with a given decay rate for the error dynamics. To show the effectiveness of the theoretical results, some simulation and experimental results on multi-robot systems have been performed. 相似文献