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131.
This paper quantitatively measures technological change in U.S. jet fighter aircraft from 1944 to the present day using the hedonic pricing approach. The technical and performance characteristics of jet fighters have changed dramatically between the time they were first developed at the beginning of the 1940s and the present. Parallel to this technological change there has been a sharp escalation in costs regarding the new generations of jet fighter aircraft. We estimate a measure of price for the performance and technical characteristics of these aircraft. Embodied technological change in jet fighter airframes is measured using quality-adjusted prices. Although the flyaway cost of jet fighter aircraft has soared, on average, by about 12.63% per year, the quality-adjusted aircraft cost has only risen by about 2.6% per year, a figure lower than the average observed general inflation rate for the period (around 4%). This represents an impressive average technological progress ratio of around 10% per year. A revealed preferences argument shows that the characteristic most valued by the government is stealth capability, followed by advanced avionics. 相似文献
132.
International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of academic and management debate. However, most studies treat MNC subsidiaries as relatively passive actors. We challenge this assumption by investigating the drivers of knowledge protection intensity of MNC subsidiaries. We argue that knowledge protection intensity is determined by MNC subsidiary mandates and by opportunities and risks originating from the host region. We hypothesize that not just competence-creating but also competence-exploiting mandates increase knowledge protection intensity. In addition, technological cluster regions in the host country can be expected to provide opportunities for knowledge sourcing and MNC subsidiaries may be willing to protect knowledge less intensively to participate in cluster networks. We test our hypotheses using a dataset of 694 observations of 631 MNC subsidiaries in Germany and develop recommendations for research, managers and policy makers. 相似文献
133.
The objective of this paper is to take an in-depth look, from a network perspective, at the role that social capital plays in improving knowledge exchange between organizations. To do this, we consider the three dimensions of social capital: the structural dimension, as measured by the position of firms bridging structural holes; the relational dimension, as gauged by the level of trust and friendship in each relationship; and the cognitive dimension, as estimated by the presence of a shared culture. We also evaluate the level of organizational and human capital present in terms of the firms in the network. Empirical evidence has been gathered from the Madrid Science Park in Spain by applying the social network analysis methodology. The results show that the three dimensions of social capital play a significant role in increasing knowledge exchange in this network, while human and organizational capital differences are only significant for a sub-sample. 相似文献
134.
Costa Ricardo V Fernández-Jardon Fernández Carlos Figueroa Dorrego Pedro 《知识管理研究与实践》2014,12(3):322-338
Knowledge Management Research & Practice - The general purpose of this research is to study interaction effects between intangible assets and product innovation. More specifically, the authors... 相似文献
135.
Consumer distrust is only recently beginning to be perceived as an important e-commerce issue and, unlike online trust, the nature and role of distrust is much less established. This study examines the influence of two important consumer characteristics (ethical ideology and risk aversion) on consumer’s ethically-based distrust of online retailers. Also, the moderating role of consumer’s need for personal contact with sales staff is tested. Results from 409 online consumers confirm that both relativist-based ethical ideology and risk aversion are strongly and positively related to consumers’ distrust. Interestingly, our findings show that positive effects of relativism and risk aversion on consumer’s distrust are moderated by consumers’ need for personal interaction, which is more pronounced for those consumers with a high need for personal interaction with retail salespeople. 相似文献
136.
Javier Noya Salces Pedro M. Gómez-Carmona Diego Moliner-Urdiales Manuel Sillero-Quintana 《Journal of sports sciences》2014,32(13):1263-1270
AbstractThe aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively. 相似文献
137.
Nina Feddermann-Demont Dominik Straumann Jiří Dvořák 《Journal of sports sciences》2014,32(13):1217-1228
AbstractA concussion is a rare but potentially serious injury of football players. Thus, an immediate and valid diagnosis, estimate of severity and therapeutic management is required. To summarise the published information on management of concussion with respect to a safe return to play (RTP), a literature search was conducted. Current guidelines on concussion in sports and significant studies on concussion in football were analysed. After concussion, management and RTP decision should remain in the area of clinical judgement on an individualised basis according to the current international guidelines. If a concussion is suspected, the player should not be allowed to RTP the same day. The RTP programme should follow a gradual step-wise procedure. A concussed player should not RTP unless he/she is asymptomatic and the neurological and neuropsychological examinations are normal. Untimely RTP bears an increased risk of sustaining another more severe brain injury and repetitive brain injury of long-term sequelae. In football, the management of concussion should primarily follow the recommendations proposed by the Concussion in Sports Group. Information and education of players and their medical and coaching team help to protect the players’ health. Future studies on concussion should include validated and detailed information on RTP protocols. 相似文献
138.
Rita Zajácz Ph.D. 《广播与电子媒介杂志》2013,57(4):652-667
This article traces the definition of the public interest from the Navy Department through the FRC, to the FCC, with regard to the right mixture of competition and monopoly in international radiotelegraphy and identifies foreign policy as an important policy area where regulatory autonomy is enhanced. Policymakers defined the public interest independently of industry pressure because of internal divisions in the industry and, more importantly, because the strategic and international dimensions of the policy area brought the Navy Department into the regulatory mix and prompted the Commission to adopt a realist, rather than a liberal, framework. 相似文献
139.
Pádraig Hogan 《牛津教育评论》2013,39(2):141-155
Abstract Instrumentalist theories are older than liberal, reconstructionist or child‐centred ones and the concept of progress they embody seems very obvious at first sight: making schools and other educational institutions more relevant to social needs. In open market societies however social needs are even more fiercely contested than are intrinsic educational values or the needs of individual childen. When a social need is politically legitimated in newly closed societies, even resolute instrumentalists may blanch at what is required of schools, as Durkheim's disciples found in occupied France. In contemporary English‐speaking societies the paradox is noted that neo‐Marxists consider educational institutions to be instruments in the hands of the ‘ruling classes’ and to be part of an Ideological State Apparatus (ISA), whereas all those who may be defined as members of such ruling classes bemoan that these institutions are dysfunctional to the needs of industry and commerce and hostile to market societies. 相似文献
140.
Juan Manuel Alvarez Méndez 《Cultura y Educación》2013,25(10):11-30
En este artículo se hace una reflexión en profundidad uniendo el proceso de enseñar en general al proceso específico de enseñanza de la redacción, que se configura como tarea interdisciplinar en torno a la escritura como eje integrador para lograr la unidad curricular. Esta reflexión se concreta en 10 prescripciones o sugerencias para la actuación. 相似文献