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191.
Abstract: The current generation of students coming into food science and engineering programs is very visually oriented from their early experiences. To increase their interest in learning, new and visually appealing teaching materials need to be developed. Two diverse groups of students may be identified based on their math skills. Food science students tend to find it difficult to use mathematics as a problem‐solving tool for food engineering problems. Food engineering students, on the other hand, should be challenged to use emerging mathematical tools to develop their problem‐solving skills. Therefore, the approach of this project involved the development of a curriculum to train undergraduate food engineers in the effective use of computational fluid dynamics (CFD) software to solve food engineering problems by engaging them in the creation of food engineering teaching tools. These CFD outputs were then used as innovative teaching tools for the food science students. In this paper, this concept will be illustrated by unsteady‐state heat transfer and fluid flow problems. To evaluate the efficiency of the teaching materials developed, a student focus group was asked to answer the same quiz following a conventional and CFD output aided teaching session. The assessment result showed an improved understanding of the subject after the CFD teaching session. These visual aids were excellent tools to illustrate the validity of the formulas presented in class. In addition, the new visual materials enabled a better understanding of the relationships among different process parameters. In general, this helped the food science students better appreciate the food engineering concepts that govern food processing operations.  相似文献   
192.
Abstract: The Cornell Critical Thinking Test (CCTT) is one of the many multiple‐choice tests with validated questions that have been reported to measure general critical thinking (CT) ability. One of the IFT Education Standards for undergraduate degrees in Food Science is the emphasis on the development of critical thinking. While this skill is easy to list as a student‐learning objective, measuring gains in CT is relatively difficult. If the majority of the class time is spent discussing and solving ill‐defined problems, then will students become actively and meaningfully involved in their own learning and will there be any gains in CT skills? To measure gains using this format, the CCTT was administered as a pre‐ and posttest to Food Science and Human Nutrition students in an Experimental Foods class taught every fall over an 8 y period (2001–2008). Statistical analysis indicated that in 2 of the years (2002 and 2004), there were significant gains (P values 0.036 and 0.045, respectively) in CT scores. Furthermore, in both years, there were significant gains in the same 2 aspects of CT (deduction and assumption) and not in the other aspects. However, we suggest that completing several take‐home exams with many open‐ended questions, writing detailed laboratory reports, and documenting unsolicited student reflections in journal entries that comment on apparent gains in CT skills may be a better indication of actual gains in CT skills compared to the actual CCTT test scores.  相似文献   
193.
This study addresses several methodological problems that have confronted prior research on the effect of class size on student achievement. Unlike previous studies, this analysis accounts for the hierarchical data structure of student achievement, where grades are nested within classes and students, and considers a wide range of class sizes across various disciplines. Based on data from undergraduate class sections at a single institution, the study provides consistent evidence of a negative effect of class size on grade performance, most substantially affecting the achievement of “A” grades with lesser effect on grades of “C” or higher. Because models with logarithmic specification show superior fit, this study also demonstrates that the effect of class size on students’ final grades diminishes as the class size increases. These findings suggest that a larger impact on student performance could be attained by further trimming enrollment in small classes than by reducing class size overall.  相似文献   
194.
A review of rubric use in higher education   总被引:5,自引:3,他引:2  
This paper critically reviews the empirical research on the use of rubrics at the post‐secondary level, identifies gaps in the literature and proposes areas in need of research. Studies of rubrics in higher education have been undertaken in a wide range of disciplines and for multiple purposes, including increasing student achievement, improving instruction and evaluating programmes. While, student perceptions of rubrics are generally positive and some authors report positive responses to rubric use by instructors, others noted a tendency for instructors to resist using them. Two studies suggested that rubric use was associated with improved academic performance, while one did not. The potential of rubrics to identify the need for improvements in courses and programmes has been demonstrated. Studies of the validity of rubrics have shown that clarity and appropriateness of language is a central concern. Studies of rater reliability tend to show that rubrics can lead to a relatively common interpretation of student performance. Suggestions for future research include the use of more rigorous research methods, more attention to validity and reliability, a closer focus on learning and research on rubric use in diverse educational contexts.  相似文献   
195.
During competition, kayak athletes must optimally adapt to environmental factors (e.g. wind, waves) to achieve peak performance. However, the ability to adapt to such perturbations has never been assessed in kayak paddling. Therefore, the aim of the current study was to evaluate the local dynamic stability in sports technique of youth sprint kayak athletes. In a cross-sectional study, 14 healthy male athletes were recruited from an elite youth sprint kayak squad. During an incremental kayak ergometer test, mean power, heart rates and local dynamic technique stability of hands, arms, trunk and paddle were registered and the association with the athletes 2000?m free-water times were estimated using mixed models. The 2000?m free-water performance significantly predicted the paddles (p?=?.037) local dynamic stability whereas no association was found for the trunk or the upper extremity kinematics. In conclusion, kayak athletes with high-performance capability over 2000?m paddling depict high local dynamic technique stability. This emphasizes the importance of a stable technique for advanced kayak skills, especially regarding paddling movements.  相似文献   
196.
Two studies investigated whether parent–child discussion of peer provocations reduces young children's hostile attributional bias. Study 1 (= 109, age 4–7)—an observational study—showed that parent–child discussion of nonhostile attributions (when reading a picture book) predicted reductions in children's hostile attributional bias from pre‐ to postdiscussion. Study 2 (= 160, age 4–6)—an experimental study—showed that stimulating parents to discuss either nonhostile attributions or normative beliefs (vs. a control condition) reduced children's hostile attributional bias in response to hypothetical vignettes, but not in response to a staged peer provocation. These findings suggest that by framing social situations, parents may help their children perceive less hostility in their social worlds.  相似文献   
197.
This study had two purposes: to explore the components of the pedagogical content knowledge (PCK) of an experienced elementary science teacher and to reveal the presumed interactions among these components. A naturalistic inquiry was conducted as a single case study in which in-depth qualitative data were gathered through semi-structured interview questions. After the theory-based and data-driven analysis of the qualitative data, the verbal communication was quantitated into numerical data for the enumerative analysis. The results revealed that the teacher’s knowledge of students’ understanding and difficulties, knowledge of the elementary science curriculum and knowledge of instructional strategies and representations were found to be mostly intersected PCK components, whereas orientations towards teaching science and knowledge of assessment in science had limited connections to the other components. Further discussions and context-based suggestions are given regarding professional development programmes.  相似文献   
198.
Laceration injuries account for up to 23% of injuries in rugby union. They are frequently caused by studded footwear as a result of a player stamping onto another player during the ruck. Little is known about the kinetics and kinematics of rugby stamping impacts; current test methods assessing laceration injury risk of stud designs therefore lack informed test parameters. In this study, twelve participants stamped on an anthropomorphic test device in a one-on-one simulated ruck setting. Velocity and inclination angle of the foot prior to impact was determined from high-speed video footage. Total stamping force and individual stud force were measured using pressure sensors. Mean foot inbound velocity was 4.3 m ? s?1 (range 2.1–6.3 m ? s?1). Mean peak total force was 1246 N and mean peak stud force was 214 N. The total mean effective mass during stamping was 6.6 kg (range: 1.6–13.5 kg) and stud effective mass was 1.2 kg (range: 0.5–2.9 kg). These results provide representative test parameters for mechanical test devices designed to assess laceration injury risk of studded footwear for rugby union.  相似文献   
199.
In its late stage, Alzheimer's disease results in progressive muscle weakness in the arms and legs. The aim of this study was to determine whether mice expressing the skeletal muscle-specific mutant PS2 gene (a model of Alzheimer's disease) are a useful experimental system to study the protective effect of exercise on Aβ-42 reduction, improvement of behavioural function and changes in metabolic parameters. With this aim in mind, the transgenic mice were subjected to treadmill exercise for 3 months. The results showed that in transgenic mice, but not in normal mice, treadmill exercise resulted in a reduction of Aβ-42 deposits and an improvement in behavioural function, thereby restoring normal concentrations of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglyceride. Thus, exercise may represent a practical therapeutic strategy for use with human patients with Alzheimer's disease.  相似文献   
200.
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