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Zusammenfassung. In diesem Artikel werden verschiedene Erlösformen für den Handel mit Web-Content und -Services vorgestellt, bewertet und miteinander verglichen. Ziel des Artikels ist es, auf der einen Seite Anbietern von digitalen Produkten und Dienstleistungen Möglichkeiten aufzuzeigen, wie sie Einnahmen erzielen können, und auf der anderen Seite WWW-Nutzer darauf einzustellen, dass und in welcher Form sie in Zukunft für den Zugriff auf qualitativ hochwertige Web-Inhalte und -Leistungen bezahlen werden müssen.Eingegangen am 18. Juni 2003, Angenommen am 2. Dezember 2003, CR Subject Classification: K.4.4, K.5.1  相似文献   
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Abstract

Management has always been about communications. Business strategy in particular can only work, if implemented. Part of the process is communicating strategy to all company's stakeholders. The more team‐orientated a management style the more communications becomes a key success factor. By the same token, there has never been a management discipline for communications in its own right comparable to all the others that have developed over time: Neither Marketing nor HR nor even Finance were part of the original settings as, for example, laid out by Erich Gutenberg in the 1960s. All these “subs”; were initiated by increasing specialisation of business administration and developed to mature disciplines.

This article will argue for yet another management discipline, communications management. The reasons are mainly twofold: on the one hand there are increasing needs on different types of communications even without the world‐wide web (such as financial communications), which must be integrated in one holistic approach. And on the other hand there are increasing new challenges caused by the digital economy (such as customer related communications), which will have to be integrated in an even advanced holistic management approach. This article will combine both reasons, but mainly focus on the first aspect.  相似文献   
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The strength of strong ties in the creation of innovation   总被引:4,自引:0,他引:4  
Katja Rost 《Research Policy》2011,40(4):588-604
There is an ongoing debate in innovation research as to which type of social capital is more conducive to innovation: structural holes as proposed by Burt or network closure as proposed by Coleman. Although Coleman focused on the quality of relationships, Burt argued that the structural configuration of relationships was more important. I argue that, instead of being alternative substitutes, Burt's social capital theory complements Coleman's theory. More precisely, I demonstrate that, in the presence of strong ties, weak network architectures (structural holes or a peripheral network position) leverage the strength of strong ties in the creation of innovation. This implies that weak network architectures have no value without strong ties, whereas strong ties have some value without weak network architectures but are leveraged by this type of structure. The findings indicate that innovation research tends to overestimate the impact of weak network architectures in the creation of innovation. By pointing to the necessity of strong ties, the results may be of particular interest for research on open innovation. They suggest that open innovation will not work if closed innovation principles are pushed back.  相似文献   
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New product development nowadays makes heavy use of IT instruments such as virtual simulation tools. The main motivation for introducing virtual simulation tools in new product development is to speed up development and lower its cost. Virtual simulation tools, however, do much more. They introduce profound changes in the organization, including the nature of problem-solving, bearing the potential to increase new product development performance beyond cost and lead time reduction. Understanding these profound changes, we argue, holds the key to unlocking the potential of virtual simulation tools for improving new product development performance, including more innovative products. We support our argument with a case study from the European auto industry.  相似文献   
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INTRODUCTION One main purpose of requirements is to de-scribe the functionality of software. Thus re-quirements often serve as a basis for contracts aswell as for communication between customers anddevelopers. However, they are usually captured innatural language accompanied by a few top-levelinformal drawings like use cases or activity dia-grams that denote the structure of the functional-ities in an abstract way. One disadvantage of naturallanguage is that the developer has to cope with…  相似文献   
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Purpose:The present study aimed to systematically review and compare 2 femoral autograft fixation techniques,namely,interference screws and suture anchors,for isolated medial patellofemoral ligament reconstruction in patients with recurrent patellofemoral instability at mid-to long-term follow-up.Methods:A literature search was performed in September 2020.All studies reporting the outcomes of primary isolated medial patellofemoral ligament reconstruction for recurrent patellofemoral instability were considered for inclusion.Only studies reporting the type of femoral autograft fixation under examination were considered.Studies reporting data from patients with elevated tibial tuberosity-tibial groove,patella alta,and/or Dejour’s trochlear dysplasia types C and D,were not included.Only articles reporting data with a minimum follow-up period of 18 months were considered.Results:Data from 19 studies(615 patients)were retrieved.The overall age was 24.4±6.7 years(mean±SD).The mean follow-up was 46.5±20.9 months.There were 76 patients in the anchor group and 539 in the screw group.Comparability was found with regard to age and follow-up duration between the 2 study groups.There was comparability between the Kujala,Lysholm,and Tegner scores at baseline.At the last follow-up,no worthy differences were found in terms of mean Kujala(+2.1%;p=0.04),Lysholm(+1.7%;p=0.05),and Tegner(+15.8%;p=0.05)scores.Although complications occurred almost exclusively in the screw cohort,no statistically significant difference was found.Conclusion:Femoral autograft fixation through interference screws or suture anchors report similar clinical scores and rate of apprehension test,persistent joint instability,re-dislocations,and revisions.These results must be interpreted within the limitations of the present study.  相似文献   
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Determination of amyloid β (Aβ) isoforms and in particular the proportion of the Aβ 1-42 isoform in cerebrospinal fluid (CSF) of patients suspected of Alzheimer's disease might help in early diagnosis and treatment of that illness. Due to the low concentration of Aβ peptides in biological fluids, a preconcentration step prior to the detection step is often necessary. This study utilized on-chip immunoprecipitation, known as micro-immunoprecipitation (μIP). The technique uses an immunosorbent (IS) consisting of magnetic beads coated with specific anti-Aβ antibodies organized into an affinity microcolumn by a magnetic field. Our goal was to thoroughly describe the critical steps in developing the IS, such as selecting the proper beads and anti-Aβ antibodies, as well as optimizing the immobilization technique and μIP protocol. The latter includes selecting optimal elution conditions. Furthermore, we demonstrate the efficiency of anti-Aβ IS for μIP and specific capture of 5 Aβ peptides under optimized conditions using various subsequent analytical methods, including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), capillary electrophoresis, microchip electrophoresis, and immunoblotting. Synthetic Aβ peptides samples prepared in buffer and spiked in human CSF were analyzed. Finally, on-chip immunoprecipitation of Aβ peptides in human CSF sample was performed.  相似文献   
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