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31.
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
32.
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
33.
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
34.
Braun Edith Spexard Anna Nowakowski André Hannover Bettina 《Tertiary Education and Management》2020,26(2):171-183
Tertiary Education and Management - Higher education institutions face the challenge to promote diversity competence. We suggest a procedure which can help raise awareness for diversity issues... 相似文献
35.
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
36.
The goal of the present study is to identify prospective special education teachers (SETs) who may have difficulties in coping with occupational stresses and burdens. International comparative studies show that SETs have a higher level of stress than their colleagues who work in the general school system. Compared with teachers in regular schools, SETs leave their profession at a higher rate. For this reason, the study focuses on so-called dysfunctional cognitions, which might increase stress in strenuous occupational situations and which have long-term harmful effects on health. The construct of dysfunctional cognitions is supposed to be a basis for developing supportive measures for teacher students with low stress tolerance. In the framework of the present study located in the German educational system, teacher students (N = 333) from the special needs areas, including learning disability, mental disability, emotional/social disorders and sensory disabilities (hearing impairment, or speech or language disorders), are taken into account. A hierarchical cluster analysis and a discriminant analysis were used to identify four different clusters: Cluster 1 shows the lowest attitude level of equally all dysfunctional cognitions. Clusters 2 and 3 are characterised by higher degrees, especially of ‘dependency’, ‘internalisation of failure’ and ‘personal standards (perfectionism)’. The fourth profile indicates the highest degree of the dysfunctional cognitions. Lower levels of dysfunctional cognitions (with the exception of perfectionism) occur together with a higher expectation of self-efficacy. No cluster applies for all teacher students of one specific special needs area. Prospective teachers in the area of mental disability are overrepresented in cluster 3, with a high level of internalisation of failure and dependency. Teacher students in the area of emotional/social disorders belong, to a considerable degree, to the ‘risk’ cluster. The profiles are used to develop measures for those teacher students who may experience difficulties in stressful occupational situations. Therefore, these student teachers need to be closely supported through additional intensive training elements and balanced career counselling. 相似文献
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This project provides a critical evaluation of networked resources as they relate to the library's collection development policy, identifies areas of the curriculum not well represented, establishes a reliable method of assessing usage across all resources, and develops a framework of quantitative data for collection development decision making. 相似文献
40.
Matthias Bender Sebastian Michel Gerhard Weikum und Christian Zimmer 《Informatik - Forschung und Entwicklung》2005,20(3):152-166
Zusammenfassung In diesem Artikel wird MINERVA pr?sentiert, eine prototypische Implementierung einer verteilten Suchmaschine basierend auf
einer Peer-to-Peer (P2P)-Architektur. MINERVA setzt auf die in der P2P-Welt verbreitete Technik verteilter Hash-Tabellen auf
und benutzt diese zum Aufbau eines verteilten Verzeichnisses. Peers in unserem Ansatz entsprechen v?llig autonomen Benutzern mit ihren lokalen Suchm"oglichkeiten, die bereit sind, ihr lokales
Wissen und ihre lokalen Suchm?glichkeiten im Rahmen einer Kollaboration zur Verfügung zu stellen. Wir formalisieren unsere
Systemarchitektur und beschreiben das zentrale Problem einer effizienten Suche nach vielversprechenden Peers für eine konkrete
Anfrage innerhalb des Verbundes. Wir greifen dabei auf existierende Methoden zurück and passen diese an unseren Systemkontext
an. Wir pr?sentieren Experimente auf realen Daten, die verschiedene dieser Ans?tze vergleichen. Diese Experimente zeigen,
dass die Qualit?t der Ans?tze variiert und untermauern damit die Wichtigkeit und den Einfluss einer leistungsstarken Methode
zur Auswahl guter Datenbanken. Unsere Experimente deuten an, dass eine geringe Anzahl sorgf?ltig ausgew?hlter Datenbanken
typischerweise bereits einen Gro?teil aller relevanten Ergebnisse des Gesamtsystems liefert.
This paper presents the MINERVA project that protoypes a distributed search engine based on P2P techniques. MINERVA is layered on top of a Chord-style overlay network and uses a powerful crawling, indexing, and search engine on every autonomous peer. We formalize our system model and identify the problem of efficiently selecting promising peers for a query as a pivotal issue. We revisit existing approaches to the database selection problem and adapt them to our system environment. Measurements are performed to compare different selection strategies using real-world data. The experiments show significant performance differences between the strategies and prove the importance of a judicious peer selection strategy. The experiments also present first evidence that a small number of carefully selected peers already provide the vast majority of all relevant results.
CR Subject Classification H.4,H.3.3,H3.4 相似文献