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961.
This study theorized and validated a model of knowledge sharing continuance in a special type of online community, the online question answering (Q&A) community, in which knowledge exchange is reflected mainly by asking and answering specific questions. We created a model that integrated knowledge sharing factors and knowledge self-efficacy into the expectation confirmation theory. The hypotheses derived from this model were empirically validated using an online survey conducted among users of a famous online Q&A community in China, “Yahoo! Answers China”. The results suggested that users’ intention to continue sharing knowledge (i.e., answering questions) was directly influenced by users’ ex-post feelings as consisting of two dimensions: satisfaction, and knowledge self-efficacy. Based on the obtained results, we also found that knowledge self-efficacy and confirmation mediated the relationship between benefits and satisfaction.  相似文献   
962.
Evaluation of college and university teaching is considered in the context of growing demands for accountability of educational institutions and particular roles of faculty in achieving goals for which these institutions are believed to be accountable. In the first of two papers,* three contemporary aprroaches to evaluation of teaching in higher education are critically reviewed. All three of these approaches-assessment of learning outcomes, assessment of teacher characteristics and analysis of pedagogical behaviors-are found to be defective on logical, theoretical and empirical grounds. A common thread of deficiency is the absence of a coherent theoretical framework for analysis of teaching and phenomena associated with teaching. Specific defecs are analyzed in each of the three approaches as well as in the ubiquitous methodology of rating of teaching performance. In analysis of evaluation by assessment of learning outcomes, teaching is shown to be neither necessary nor sufficient to subsequent learning outcomes. Assessment of teacher characteristics fails to identify those characteristics peculiarly indigenous to teaching as a generic activity. Analysis of pedagogical behaviors fails to distinguish critical teaching acts from more general teacher characteristics interpretable in terms of teacher personality. Furthermore, no adequate basis is provided for normative interpretation of data pertaining to pedagogical behaviors. The use of rating scales to provide data about teacher characteristics or pedagogical behavior rests on assumed rather than demonstrated validity of results. Evidence of validity or meaningfulness is replaced by evidence of consistency which is often spurious. The first paper concludes with an outline of requirements for a more constructive approach to the task of teacher evaluation. In a second paper, an outline of a theory of teaching is sketched which conforms to these requirements. Realization of this theoretical structure in teaching assessment report forms is described. Tentative conclusions from trial use of forms-in-development and recommendations for additional data sources are discussed in terms of their potential contribution to improvement in teaching.  相似文献   
963.
Data were collected from 289 undergraduate college students at a minority‐serving institution to explore the impact of academic rational beliefs on grit and resilience. Findings from hierarchical regression analyses suggested that academic rational beliefs related to evaluation and work habits accounted for a significant amount of variance in grit. Work habits explained a significant portion of the variance in resilience. On the basis of these results, recommendations for future research and implications for college counselors are offered.  相似文献   
964.
The Course-Faculty Instrument (CFI) demonstrates similar measurement properties with student populations at four diverse institutions. These students agree about the nature and extent to which course and instructor attributes relate to their learning. The results suggest that: (1) a perceived learning criterion may have general relevance to students, and (2) validity extension research is an economically feasible alternative to full-scale instrument development and validation efforts. Since validity extension is practical and facilitates cross-institutional comparisons, it appears to be a more viable strategy for researching and instituting student evaluation systems than is suggested by its current usage.  相似文献   
965.
The primary objective for modeling of machining processes is to develop a predictive capability of machining performance in order to facilitate effective planning of machining operations. This capability leads to faster implementation, higher performance, quality at a lower cost. This comes about due to improved selection of machining parameters, optimal fixture design and the avoidance of tool failure. The simulation system presented simultaneously considers the effect of cutter geometry, the cutter's initial position errors, workpiece geometry, machine tool dynamics, and workpiece/fixture system dynamics on the machining process.The integration of all of the above in one model provides an off-line tool to simulate and optimize the machining parameters and the fixture configuration cutting both lead and production time. The modular nature of the simulation system presented allows for the study of many different machining processes. The cutting forces in this system are modeled using a mechanistic approach. NURBS curves and surfaces are utilized for the geometric modeling and simulation of the machining process. While a finite element method is used to model and analyze the workpiece/fixture dynamics. Two case studies are presented to demonstrate the practical application of the presented simulation. The first case presents the optimization of the fixture configuration of a generic automotive component. While the second case presents the results of simulations performed on a novel mill/grind machining process. This process is a combination of face milling and grinding in one operation. Some simulated results are presented along with experimental validation.  相似文献   
966.
Whilst previous research has highlighted significant relationships between golfers’ clubhead velocity (CHV) and their vertical jump height and maximum strength, these field-based protocols were unable to measure the actual vertical ground reaction force (vGRF) variables that may correlate to performance. The aim of this study was to investigate relationships between isometric mid-thigh pull (IMTP), countermovement jump (CMJ), squat jump (SJ) and drop jump (DJ) vGRF variables and CHV in highly skilled golfers. Twenty-seven male category 1 golfers performed IMTP, CMJ, SJ and DJ on a dual force platform. The vertical jumps were used to measure positive impulse during different stretch-shortening cycle velocities, with the IMTP assessing peak force (PF) and rate of force development (RFD). Clubhead velocity was measured using a TrackMan launch monitor at a golf driving range. Pearsons correlation coefficient analyses revealed significant relationships between peak CHV and CMJ positive impulse (r = 0.788, < 0.001), SJ positive impulse (r = 0.692; < 0.001), DJ positive impulse (r = 0.561, < 0.01), PF (r = 0.482, < 0.01), RFD from 0–150 ms (r = 0.343, < 0.05) and RFD from 0–200 ms (r = 0.398, < 0.05). The findings from this investigation indicate strong relationships between vertical ground reaction force variables and clubhead velocity.  相似文献   
967.
The clinical use of ultrasound has dramatically increased, necessitating early ultrasound education and the development of new tools in ultrasound training and assessment. The goal of this study was to devise a novel low-resource examination that tested the anatomical knowledge and technical skill of early undergraduate medical students in a gross anatomy course. The team-based ultrasound objective structured practice examination (OSPE) was created as a method for assessing practical ultrasound competencies, anatomical knowledge, and non-technical skills such as teamwork and professionalism. The examination utilized a rotation of students through four team roles as they scanned different areas of the body. This station-based examination required four models and four instructors, and tested ultrasound skills in the heart, abdominal vessels, abdominal organs, and neck regions. A Likert scale survey assessed student attitudes toward the examination. Survey data from participants (n = 46) were examined along with OSPE examination grades (n = 52). Mean and standard deviations were calculated for examination items and survey responses. Student grades were high in both technical (96.5%). and professional (96.5%) competencies with structure identification scoring the lowest (93.8%). There were no statistical differences between performances in each of the body regions being scanned. The survey showed that students deemed the examination to be fair and effective. In addition, students agreed that the examination motivated them to practice ultrasound. The team-based OSPE was found to be an efficient and student-favored method for evaluating integrated ultrasound competencies, anatomical knowledge, team-work, and professional attributes.  相似文献   
968.
969.
Newly hatched chicks were force-fed food and water throughout rearing, and food, water, or sand reinforcers during exposure to an omission-training procedure. The chicks were thus prevented from performing approach and contact responses to the reinforcer at any time in their lives. Nevertheless, the subjects displayed approach and species-specific feeding or drinking reactions directed toward an illuminated key paired with food or water, but not with sand. Illumination of a key either uncorrelated or negatively correlated with food or water did not engender appreciable responding. Feeding and drinking reactions were topographically distinct, determined by the type of reinforcer, but were not elicited by the reinforcer. These findings support a “learned release” view of autoshaping, according to which phylogenetically preorganized behavior patterns are triggered by distal stimuli paired with biologically significant proximal stimulation, and suggest a close relationship between autoshaping and primitive instances of visual object recognition.  相似文献   
970.
This paper describes how an undergraduate department in the School of Education at the University of Wisconsin-Milwaukee grants college credits for previous learning experiences to attract and retain nontraditional students from an urban environment. At first students earned these credits by writing a loose biography, but the process by which these credits are earned has become more structured. These Prior Professional Educational Experience credits (as they are named) are now granted on a course-specific basis, where students respond in writing to questions designed to test their knowledge of competency areas offered by the department. Earning these credits has helped older students get through the university and has given them a sense of accomplishment about learnings acquired in nonuniversity settings.  相似文献   
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