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31.
32.
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   
33.
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   
34.
This paper aims to demonstrate how the huge amount of Social Big Data available from tourists can nurture the value creation process for a Smart Tourism Destination. Applying a multiple-case study analysis, the paper explores a set of regional tourist experiences related to a Southern European region and destination, to derive patterns and opportunities of value creation generated by Big Data in tourism. Findings present and discuss evidence in terms of improving decision-making, creating marketing strategies with more personalized offerings, transparency and trust in dialogue with customers and stakeholders, and emergence of new business models. Finally, implications are presented for researchers and practitioners interested in the managerial exploitation of Big Data in the context of information-intensive industries and mainly in Tourism.  相似文献   
35.
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   
36.
Mechanochemistry     
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   
37.
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.
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   
38.
We use the 2003 National Survey of College Graduates to provide the first estimates of the effect on earnings of having a double major. Overall, double majoring increases earnings by 2.3% relative to having a single major among college graduates without graduate degrees. Most of the gains from having a double major come from choosing fields across two different major categories. Graduates who combine an arts, humanities or social science major with a major in business, engineering, science or math have returns 7–50% higher than graduates with a single major in arts, humanities or social science. But such double major combinations have returns no higher than single majors in business, engineering, science or math. Majors combining business and science or math have returns more than 50% greater than the returns to having a single major in these fields.  相似文献   
39.
The Urban Review - School choice policy is ubiquitous in urban school districts. Evidence suggests that it has not fully delivered on its proponents’ promises of equitable educational...  相似文献   
40.
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   
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