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排序方式: 共有192条查询结果,搜索用时 15 毫秒
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Research and development (R&D) is often essential for firms’ profitability and growth. At the same time, R&D is long-term and risky. We show that innovation activities lead to information ambiguity about the future value of firms’ assets. This effect appears to be more pronounced for small and less reputed firms. Information ambiguity further lowers firms’ market value and, in particular, the market value of innovative assets. We further show that high quality patents mitigate the negative effect of information ambiguity to some extent. 相似文献
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This study investigates the effect of project-level collaboration breadth (i.e., the number of collaboration partner types) and collaboration depth (i.e., the intensity of the interactions with these partners) on the incremental and radical innovation performance of innovation projects. The econometric analyses, based on a Community Innovation Study sample of 218 innovation projects conducted in German manufacturing companies, reveal inverted U-shaped relationships between collaboration breadth and radical innovation performance and between collaboration depth and incremental innovation performance. These curvilinear effects speak to the high sensitivity of innovation projects to the extent of collaborative activity, which implies that practitioners should exert caution in managing collaborative innovation projects. This study contributes to the understanding of project-level open innovation and to the overall understanding of the performance effects of innovation collaboration, which, following recent assertions in the literature, could be flawed by analyses conducted at the organizational level. 相似文献
24.
Ainara Larrondo Ureta 《Journalism Practice》2020,14(8):991-1007
ABSTRACT According to a growing volume of academic literature on the subject, transmedia fiction and non-fiction production is now one of the main areas driving innovation in media companies, thanks to the improvements it brings in numerous interconnected fields: narrative and content, management and productive strategy, brand promotion, etc. In this context the article focuses on transmedia linked to public broadcasting companies, starting with a qualitative study based on interviews with expert professionals from thirteen corporations in Spain, one operating at the national level (RTVE) and twelve at the regional level (A Punt Media, CARTV, CCMA, CRTVG, CMM, EITB, EPRTVIB, RTVM, RTPA, RTVA, RTRM and RTVC). The results show how professionals view the concept of transmedia production, its advantages, disadvantages and the challenges it poses, which depend on these corporations’ service and relationship with audiences. As the conclusions state, the keys factors for understanding the professional transmedia strategy of public broadcasting corporations are found in the characteristics of today’s media market, which is suffering from budget cuts and growing competition. 相似文献
25.
In two experiments, this study presents a process model that explains third-person perceptions (TPP) as a function of perceived persuasive intent and reactance. Using two nonstudent samples, findings were internally replicated for two topics. The study shows that media messages evoking perceptions of persuasive intent also activate reactance, which in turn predicts TPP topic-independently. Remarkably, half of the total stimulus effect on TPP could be explained through reactance, which offers new implications for existing theoretical explanations of strong TPP after undesirable messages but weak effects after, for example, prosocial messages. 相似文献
26.
K L Sebastian 《Resonance》2007,12(5):48-59
Nano-sized molecular motors, which consume chemicals and do mechanical work are ubiquitous in nature. One of the most powerful
such motors is the viral packaging motor, which consumes ATP and packages the viral DNA into the procapsid (the protein shell)
of the virus. A pulling force applied to the loose end of the DNA can slow down the rate of packaging, thus showing that a
mechanical force can slow down a chemical reaction. In this article we describe this packaging process and what is known about
the mechanochemistry of the motor.
K L Sebastian is a Professor in the Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore.
His areas of interest is theoretical chemistry. 相似文献
27.
Michael Br?uninger Sebastian Schr?er Sven Schulze und Henning V?pel 《Zeitschrift für Erziehungswissenschaft》2008,32(1):37-45
Zusammenfassung Angesichts der staatlichen Klimaschutzziele stellt sich die Frage, wie diese mit m?glichst geringer Beeintr?chtigung einer
sicheren Versorgung zu günstigen Preisen erreichbar sind. Erdgas, das im Vergleich zu anderen fossilen Energietr?gern deutlich
kohlenstoff?rmer ist und darüber hinaus bei der Verbrennung auch keine weiteren Schadstoffe emittiert, kann hier einen Beitrag
leisten. Gegenw?rtig hat Erdgas für die Versorgung mit W?rme sowie bei der Erzeugung von Strom eine erhebliche Bedeutung,
die zukünftig weiter wachsen wird. Anhand verschiedener Szenarien werden Prognosen zur weiteren Entwicklung von Erdgas und
die Auswirkungen auf die CO2-Emissionen angestellt. Es zeigt sich, dass der Anteil von Erdgas im Bereich der W?rmeversorgung von 46 % auf 56 % steigen
wird. Durch ?nderung des Energiemix und Effizienzsteigerungen kann der CO2-Aussto? für Raumw?rme daher bis 2020 um 8,3 % gesenkt werden. Für die Stromerzeugung werden alternative Szenarien berechnet.
Beim derzeitigen Energiemix k?me es zu einer j?hrlichen Steigerung des CO2-Aussto?es um 0,8 %. Würde Kohle komplett durch Gas ersetzt, k?nnte der CO2-Aussto? j?hrlich um 1,9 % gesenkt werden.
Dieser Beitrag ist eine Kurzfassung der Studie „Wirtschaftsfaktor Erdgasbranche“, HWWI Policy Paper 1–3, Hamburg 相似文献
Given the governmental climate targets, the question arises how these targets can be achieved without affecting a secure and cheap energy supply. As natural gas causes less carbon emissions than any other fossil fuel it might be able to make a contribution in this regard. Currently, in the generation of heat and power natural gas plays a significant role, which will further increase in the future. Using several scenarios, we predict the development of the importance of natural gas and the consequences for carbon emissions. The calculations show that the share of natural gas for the supply of heat will increase from 46 % to 56 %. Efficiency increases together with changes in the structure of power generation can reduce heating-related carbon emissions by 8.3 % until 2020. For power generation, we calculate alternative scenarios. If the current structure of power generation is held constant, carbon emissions will increase by 0.8 % p.a. If instead natural gas completely replaces coal and lignite, the carbon emissions will be reduced by 1.9 % per year.
Dieser Beitrag ist eine Kurzfassung der Studie „Wirtschaftsfaktor Erdgasbranche“, HWWI Policy Paper 1–3, Hamburg 相似文献
28.
Manuelito Biag Sebastian Castrechini 《Journal of Education for Students Placed at Risk》2016,21(3):157-173
Full-service community schools are designed to increase students, and families' access to comprehensive and coordinated supports, services, and programs such as medical care, food aid, and enrichment activities. Despite widespread support, the research base documenting the efficacy of community schools is still emerging. Analyzing longitudinal data from 6 low-income, predominantly Latino community schools, this case study investigated whether students' participation in community-school programming influenced their attendance and achievement. Multilevel models indicated that youth who participated in extended learning programs or whose families were involved in family engagement opportunities exhibited greater attendance rates and achievement in math and English language arts, when compared to their nonparticipating peers. Findings provide promising evidence on the value of a comprehensive and integrated system of school supports that address the myriad needs of vulnerable student populations. 相似文献
29.
Kristin Altmeyer Sebastian Kapp Michael Thees Sarah Malone Jochen Kuhn Roland Brünken 《British journal of educational technology : journal of the Council for Educational Technology》2020,51(3):611-628
Learning with hands-on experiments can be supported by providing essential information virtually during lab work. Augmented reality (AR) appears especially suitable for presenting information during experimentation, as it can be used to integrate both physical and virtual lab work. Virtual information can be displayed in close spatial proximity to the correspondent components in the experimentation environment, thereby ensuring a basic design principle for multimedia instruction: the spatial contiguity principle. The latter is assumed to reduce learners' extraneous cognitive load and foster generative processing, which supports conceptual knowledge acquisition. For the present study, a tablet-based AR application has been developed to support learning from hands-on experiments in physics education. Real-time measurement data were displayed directly above the components of electric circuits, which were constructed by the learners during lab work. In a two group pretest–posttest design, we compared university students' (N = 50) perceived cognitive load and conceptual knowledge gain for both the AR-supported and a matching non-AR learning environment. Whereas participants in both conditions gave comparable ratings for cognitive load, learning gains in conceptual knowledge were only detectable for the AR-supported lab work. 相似文献
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