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91.
Performance support systems are mechanisms enabling users) productivity while reducing training expenses as support is being delivered in real time, often eliminating the need for costly pre‐performance training. Mobile technologies have created new opportunities for improved performance support systems, especially for tasks performed outside the offi ce. This article describes the fi rst mobile learning and performance support initiative taken by the Israeli Air Force. The project included the development and eff ectiveness pilot study of a learning and performance support application delivered via tablet to helicopter engine technicians. The application provided support videos and illustrations of maintenance routines, thereby enabling learning and practicing at the same time. Pilot study results show high performance levels of application users compared to those applying traditional methods. Results also show that self‐effi cacy levels were not aff ected by the successful performance achieved when using the mobile performance support application. Plans to expand mobile support use are also described.  相似文献   
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Zusammenfassung. In diesem Beitrag wird eine Methode zur Konstruktion robuster Klassenhierarchien vorgestellt. Hierzu wird aus den überlegungen bezüglich der polymorphen Verwendung von Klassen [2] eine Vorgehensweise zur Konstruktion von Klassenhierarchien abgeleitet. Die Begriffe Konformit?t und Spezialisierung werden verfeinert, indem nicht mehr s?mtliche Methoden einer Klasse, sondern Teilmengen davon betrachtet werden. Dies führt zum Begriff der partiellen Konformit?t. In Erweiterung von [2] sind partiell konforme Klassen dann polymorph verwendbar, wenn der Anwendungskontext, der sich aus der Benutzung der Klasse ergibt, sich ausschlie?lich auf konforme Methoden erstreckt. Diese Eigenschaft ist statisch zur übersetzungszeit überprüfbar. Damit k?nnen Fehlbenutzungen bereits zur übersetzungszeit ausgeschlossen werden. Eingegangen am 24. Dezember 1996 / Angenommen am 15. Oktober 1997  相似文献   
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This study investigated the relations of early working‐memory abilities (phonological and visual‐spatial short‐term memory [STM] and complex memory and episodic buffer memory) and later developing reading skills. Sixty Hebrew‐speaking children were followed from kindergarten through Grade 5. Working memory was tested in kindergarten and reading in Grades 1, 2, and 5. All memory measures, but phonological STM, correlated with reading up to Grade 5. Regression analyses (with intelligence quotient controlled) demonstrated that phonological complex memory predicted all reading skills in Grade 1, and accuracy in Grade 2. The rather understudied visual‐spatial memory predicted comprehension in Grades 2 (STM) and 5 (complex memory). The results point to an important role of the phonological complex memory in early assessment, and suggest a long‐lasting role of early visual‐spatial memory in predicting variance in reading. Whether this role of the visual‐spatial memory is unique to the Hebrew orthography because of its visual features requires, however, further investigation.  相似文献   
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To explore the citation evolution of papers published in the same year but different month, we selected papers from a discipline (physical geography), a subject (diabetes: endocrine and metabolism) and a journal (Journal of Biological Chemistry) published in 2005 as research objects. These papers were divided into six groups according to the difference in publication month, and we analyzed citations to these papers for the 9 years after publication. The results showed that within 5 years after papers from physical geography were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); after that, the differences were not statistically significant. Within 5 years after papers from diabetes (endocrine and metabolism) were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Within 7 years after papers from the Journal of Biological Chemistry were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Citations of papers followed the same pattern irrespective of discipline, subject or journal: citations of papers published in the same year but different month were obviously different in the first few publishing years, but as time went on, only the difference in publication month in a calendar year did not affect the papers' longer‐term citation.  相似文献   
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Implantable drug delivery systems can provide long-term reliability, controllability, and biocompatibility, and have been used in many applications, including cancer pain and non-malignant pain treatment. However, many of the available systems are limited to zero-order, inconsistent, or single burst event drug release. To address these limitations, we demonstrate prototypes of a remotely operated drug delivery device that offers controllability of drug release profiles, using osmotic pumping as a pressure source and magnetically triggered membranes as switchable on-demand valves. The membranes are made of either ethyl cellulose, or the proposed stronger cellulose acetate polymer, mixed with thermosensitive poly(N-isopropylacrylamide) hydrogel and superparamagnetic iron oxide particles. The prototype devices'' drug diffusion rates are on the order of 0.5–2 μg/h for higher release rate designs, and 12–40 ng/h for lower release rates, with maximum release ratios of 4.2 and 3.2, respectively. The devices exhibit increased drug delivery rates with higher osmotic pumping rates or with magnetically increased membrane porosity. Furthermore, by vapor deposition of a cyanoacrylate layer, a drastic reduction of the drug delivery rate from micrograms down to tens of nanograms per hour is achieved. By utilizing magnetic membranes as the valve-control mechanism, triggered remotely by means of induction heating, the demonstrated drug delivery devices benefit from having the power source external to the system, eliminating the need for a battery. These designs multiply the potential approaches towards increasing the on-demand controllability and customizability of drug delivery profiles in the expanding field of implantable drug delivery systems, with the future possibility of remotely controlling the pressure source.  相似文献   
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During economic development, modern museums face competition from various leisure activities and entertainment sites, and to achieve sustainable development, museums should reflect on providing high‐quality service to satisfy visitors’ expectations. Based on service design‐related theories, this research team conducted a case study to explore the planning, implementation, and meaning of Mobile Museums. It investigated design development from the perspective of public service design and summarized the policy, design, and service satisfaction results for Mobile Museums. Finally, the similarities in service processes are discussed between Mobile Museums and the general service industry. According to this study, attracting more visitors is the biggest issue facing museums today, as are the ways in which museums must actively provide service and become recognized to compete with others. This study identifies the onstage and backstage support of museums as well as their cultural features and non‐profit services.  相似文献   
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