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This paper discusses implications of the convergence of legal and organizational issues in the context of developing and implementing digital government projects in large urban settings. By the convergence of legal and organizational issues we refer to two important aspects of urban government: (1) the close relationship between legal/policy structures and the way government is organized and functions, and (2) the way the legal/policy elements interact with organizational dynamics and work cultures to influence digital government projects (and government activities generally). It is our contention that convergence in the organizational and legal/policy context is a powerful determinant of how these projects develop and how likely they are to succeed. Therefore the understanding of this convergence and related dynamics is critically important to planning and designing both policy to promote digital government and particular digital government projects themselves. Illustrations of this convergence and its consequences are presented. They are based on research involving two digital government projects in urban settings: development of a management information system for homeless shelter administration and a developing a system for sharing information among New York City agencies. 相似文献
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Anthony J. Shinkfield 《Journal of Personnel Evaluation in Education》1994,8(3):251-266
Conclusion The St. Peter's College application of the Shinkfield model has proved itself to be a most attractive, successful approach for the evaluation of teachers. Provided that the teacher is being evaluated only with the expectation of positive outcomes in mind, improvement as a professional practitioner of teaching most likely will occur.The approach also has shown that the teacher-appraisal function can be a facilitating and enhancing process, characterized by openness of approach, mutual respect between teacher and principal and heightened awareness of the importance to teaching of mastery of particular skills and competencies. Any successful climate of process such as the one described here must strengthen the school itself and, more particularly, student learning.A South Australian with extensive experience in educational evaluation, Anthony Shinkfield is a member of CREATE's National Advisory Panel. 相似文献
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The evolution of graduate education in electrical engineering began in the early 1890' s and progressed at a rapid pace in the 1920' s, particularly in metropolitan areas conscious of community needs. In these areas, evening programs held the spotlight because of the ever-demanding need to provide graduate engineers with advanced knowledge. Such cooperation between community interests and colleges has resulted in a wide variety of patterns of part-time study on campus and, more recently, off campus. The later development is viewed with criticism in several educational circles although off-campus programs are filling tremendous requirements arising from industrial concentrations not within easy reach of a university or college. The evolution seems to indicate that off campus programs are not a passing fancy and that such requirements are very likely to be best satisfied in the long run by the establishment of graduate centers with a faculty in residence. As an example, the Polytechnic Graduate Center on Long Island is described. (The Center, actually located in Farmingdale, N. Y., began its operation on September 25, 1961, with a graduate student body of nearly 700 in day and evening programs involving advanced courses in Aerospace Engineering, Electrical Engineering, Electrophysics, Mathematics, Mechanical Engineering, Physics, and Industrial Management. Close to 150 part-time day students are attending on a released-time basis, in addition to 45 full-time students in residence.) 相似文献
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In this paper, a detailed numerical and experimental investigation into the optimisation of hydrodynamic micro-trapping arrays for high-throughput capture of single polystyrene (PS) microparticles and three different types of live cells at trapping times of 30 min or less is described. Four different trap geometries (triangular, square, conical, and elliptical) were investigated within three different device generations, in which device architecture, channel geometry, inter-trap spacing, trap size, and trap density were varied. Numerical simulation confirmed that (1) the calculated device dimensions permitted partitioned flow between the main channel and the trap channel, and further, preferential flow through the trap channel in the absence of any obstruction; (2) different trap shapes, all having the same dimensional parameters in terms of depth, trapping channel lengths and widths, main channel lengths and widths, produce contrasting streamline plots and that the interaction of the fluid with the different geometries can produce areas of stagnated flow or distorted field lines; and (3) that once trapped, any motion of the trapped particle or cell or a shift in its configuration within the trap can result in significant increases in pressures on the cell surface and variations in the shear stress distribution across the cell’s surface. Numerical outcomes were then validated experimentally in terms of the impact of these variations in device design elements on the percent occupancy of the trapping array (with one or more particles or cells) within these targeted short timeframes. Limitations on obtaining high trap occupancies in the devices were shown to be primarily a result of particle aggregation, channel clogging and the trap aperture size. These limitations could be overcome somewhat by optimisation of these device design elements and other operational variables, such as the average carrier fluid velocity. For example, for the 20 μm polystyrene microparticles, the number of filled traps increased from 32% to 42% during 5–10 min experiments in devices with smaller apertures. Similarly, a 40%–60% reduction in trapping channel size resulted in an increase in the amount of filled traps, from 0% to almost 90% in 10 min, for the human bone marrow derived mesenchymal stem cells, and 15%–85% in 15 min for the human embryonic stem cells. Last, a reduction of the average carrier fluid velocity by 50% resulted in an increase from 80% to 92% occupancy of single algae cells in traps. Interestingly, changes in the physical properties of the species being trapped also had a substantial impact, as regardless of the trap shape, higher percent occupancies were observed with cells compared to single PS microparticles in the same device, even though they are of approximately the same size. This investigation showed that in microfluidic single cell capture arrays, the trap shape that maximizes cell viability is not necessarily the most efficient for high-speed single cell capture. However, high-speed trapping configurations for delicate mammalian cells are possible but must be optimised for each cell type and designed principally in accordance with the trap size to cell size ratio. 相似文献