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71.
The literature on Cultural Economics provides us with some examples for the measurement of technical efficiency. However, there are few case studies dedicated to the analysis of allocative efficiency. The aim of this paper is to fill this gap by incorporating a methodology that analyses both technical and allocative efficiency. We use the Shephard’s distance function, particularly suitable when affronted with non-profit-making firms or institutions that are not interested in cost minimization. As an empirical application, we analyse the efficiency of Fundación Princesa de Asturias (PAF), a Spanish non-governmental organization devoted to promoting the cultural, scientific and humanistic values of universal heritage, the period of study being 1988–2012. Our findings suggest that PAF could have used 7% less inputs to achieve the same level of output. On the other hand, we have found allocative inefficiency. Concretely, the input for other expenditures appears to have been over-utilized in relation to both the inputs for labour and current assets, with labour in turn being over-utilized in relation to current assets. Moreover, our results indicate that both technical and allocative efficiency have clearly improved during the period analysed. In summary, our empirical application shows how distance function methodology can be successfully implemented to measure allocative efficiency in cultural firms and institutions. 相似文献
72.
Jorge Ibáñez-Gijón Martinus Buekers Antoine Morice Guillaume Rao Nicolas Mascret Jérome Laurin 《Journal of sports sciences》2017,35(3):290-301
After more than 20 years since the introduction of ecological and dynamical approaches in sports research, their promising opportunity for interdisciplinary research has not been fulfilled yet. The complexity of the research process and the theoretical and empirical difficulties associated with an integrated ecological-dynamical approach have been the major factors hindering the generalisation of interdisciplinary projects in sports sciences. To facilitate this generalisation, we integrate the major concepts from the ecological and dynamical approaches to study behaviour as a multi-scale process. Our integration gravitates around the distinction between functional (ecological) and execution (organic) scales, and their reciprocal intra- and inter-scale constraints. We propose an (epistemological) scale-based definition of constraints that accounts for the concept of synergies as emergent coordinative structures. To illustrate how we can operationalise the notion of multi-scale synergies we use an interdisciplinary model of locomotor pointing. To conclude, we show the value of this approach for interdisciplinary research in sport sciences, as we discuss two examples of task-specific dimensionality reduction techniques in the context of an ongoing project that aims to unveil the determinants of expertise in basketball free throw shooting. These techniques provide relevant empirical evidence to help bootstrap the challenging modelling efforts required in sport sciences. 相似文献
73.
J. Santos-Concejero N. Tam D. R. Coetzee J. Oliván T. D. Noakes R. Tucker 《Journal of sports sciences》2017,35(6):531-538
The aim of this study was to determine whether gait cycle characteristics are associated with running economy in elite Kenyan runners. Fifteen elite Kenyan male runners completed two constant-speed running sets on a treadmill (12 km ·h?1 and 20 km ·h?1). VO2 and respiratory exchange ratio values were measured to calculate steady-state oxygen and energy cost of running. Gait cycle characteristics and ground contact forces were measured at each speed. Oxygen cost of running at different velocities was 192.2 ± 14.7 ml· kg?1· km?1 at 12 km· h?1 and 184.8 ± 9.9 ml· kg?1· km?1 at 20 km· h?1, which corresponded to a caloric cost of running of 0.94 ± 0.07 kcal ·kg?1·km?1 and 0.93 ± 0.07 kcal· kg?1· km?1. We found no significant correlations between oxygen and energy cost of running and biomechanical variables and ground reaction forces at either 12 or 20 km· h?1. However, ground contact times were ~10.0% shorter (very large effect) than in previously published literature in elite runners at similar speeds, alongside an 8.9% lower oxygen cost (very large effect). These results provide evidence to hypothesise that the short ground contact times may contribute to the exceptional running economy of Kenyan runners. 相似文献
74.
This study aimed to compare the effect of 6 weeks of resistance training or combined resistance training and change of direction exercises on physical performance and motor skills in futsal players. Thirty-four futsal players were divided into full squat group (SG, n = 12), combined full squat and change of direction exercises group (S+CDG, n = 12) and control group (CG, n = 10). The resistance training for SG consisted of full squat with low load (~45–58% 1RM) and low volume (4–6 repetitions), whereas the S+CDG performed the same resistance training program combined with loaded change of direction. Sprint time in 10 and 20 m, change of direction test, countermovement vertical jump (CMJ) height, maximal strength and force–velocity relationship in full squat exercise, kicking speed ball (BSmean) and repeated sprint ability (RSAmean) were selected as testing variables. Both experimental groups showed significant improvements for CMJ, BSmean and all strength parameters. Only SG resulted in significant sprint gains, whereas S+CDG also achieved significant improvements in RSAmean. The CG remained unchanged after training period. No significant differences were found between both experimental groups. These findings suggest that only 12 sessions of either lightweight resistance training alone, lifting the load at maximal intended velocity or combined with change of direction exercises is enough to improve several physical and skills capacities critical to futsal performance in adult players. 相似文献
75.
This work studies the information that the historiography on King Alfonso XI of Castile offers on the Marīnid dynasty of Fes. In spite of the confrontation between the two states in the thirteenth and fourteenth centuries for the control of the Strait of Gibraltar and the southern part of Andalusia, the Alfonsine texts (the Crónica del Rey don Alfonso el Onceno, the Gran Crónica de Alfonso XI and, to a lesser extent, the Poema of Alfonso Onceno) attempt to reconstruct the history of the rival sultanate through a verifiable and rigorous approach comparing with Arab sources from that period. In this regard, their ideological conception moves away from the usual stereotypes, which are generally negative in the way they portray the other, i.e. the Maghribi opponent. In contrast, Alfonsine historiography assumes the empathetic portrayal of the identity values of the rival as part of the task of the historian, and uses the history and deeds of the adversaries to highlight the victory of the Castilian monarch over them. 相似文献
76.
The international political economy of the hack: A closer look at markets for cybersecurity software
This article examines the development of hacking and cybersecurity software packages as commodities, based on an international political economy of vendors and clients operating in the interstices of international law. Offensive hacking and defensive cybersecurity tools offer new means for surveillance of critics, journalists, and human rights workers, especially in corrupt or authoritarian political systems. The article provides a case study of the Hacking Team, an international “cybersecurity” firm offering spyware and surveillance systems to government security agencies, which was itself hacked and “doxed” in 2015. The leak of documents contributes new knowledge of an international political economy for software products, which exploits the digital rights of targets and which could further undermine general Internet security. 相似文献
77.
Paolo Bardella Irene Carrasquilla García Marco Pozzo Julio Tous-Fajardo Eduardo Saez de Villareal 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(1):102-114
The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality. 相似文献
78.
Jaymee R. Shell Shawn M. K. Robbins Philippe C. Dixon Philippe J. Renaud René A. Turcotte Tom Wu 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):313-324
The forward skating start is a fundamental skill for male and female ice hockey players. However, performance differences by athlete’s sex cannot be fully explained by physiological variables; hence, other factors such as skating technique warrant examination. Therefore, the purpose of this study was to evaluate the body movement kinematics of ice hockey skating starts between elite male and female ice hockey participants. Male (n = 9) and female (n = 10) elite ice hockey players performed five forward skating start accelerations. An 18-camera motion capture system placed on the arena ice surface captured full-body kinematics during the first seven skating start steps within 15 meters. Males’ maximum skating speeds were greater than females. Skating technique sex differences were noted: in particular, females presented ~10° lower hip abduction throughout skating stance as well as ~10° greater knee extension at initial ice stance contact, conspicuously followed by a brief cessation in knee extension at the moment of ice contact, not evident in male skaters. Further study is warranted to explain why these skating technique differences exist in relation to factors such as differences in training, equipment, performance level, and anthropometrics. 相似文献
79.
Vítor P. Lopes David F. Stodden Luis P. Rodrigues 《Physical Education & Sport Pedagogy》2017,22(6):589-602
Background: Motor skill (MS) competence is an important contributing factor for healthy development.Purpose: The goal was to test the effectiveness of primary school physical education (PE) on MS and physical fitness (PF) development.Methods: Three classes (n?=?60, aged 9.0?±?0.9) were randomly assigned to three diverse conditions during a school year: two PE lessons/week (PE-2), three PE lessons/week (PE-3), and no PE lessons control group (CG). BMI, skinfolds, PF (9-min run/walk, sit-up, modified pull-ups), gymnastics, soccer, handball, basketball and track-and-field skills were evaluated. Effect sizes (d) were reported as magnitude of change.Results: Skinfolds significantly increased only in CG (d?=?1.21). PF composite z-scores improved in PE-3 (d?=?0.61), but decreased in PE-2 (d?=?0.57), and had no changes in CG. Statistically significant improvement was verified in gymnastics and handball skills in both experimental groups (gymnastic: d?=?2.95 and d?=?2.61 for PE-3 and PE-2, respectively; handball: d?=?1.87 and d?=?0.57 for PE-3 and PE-2, respectively), and no changes were seen in CG. In soccer, there were improvements only in the PE-3 (d?=?0.55), and in basketball only in PE-2 (d?=?0.46). There were no changes in any group for track-and-field skills.Conclusions: PE programs can effectively promote PF and MS development. 相似文献
80.
Ciarán Dunne 《Sport in Society》2017,20(11):1780-1798
Building on a large body of extant international research, which has consistently found that sportswomen are underrepresented and marginalized in media reporting, this article presents a study examining the coverage of sportswomen over a four-month period in a major Irish broadsheet newspaper, The Irish Times. The findings, which are based on a data-set of 471 pages, reveal that less than 4% of photographs were of sportswomen. These findings indicate that the Irish situation mirrors international research on the topic and reflects a continuation of the status quo in terms of how sportswomen and women’s sports are (under)valued and (under)reported in the media. The implications of these findings are discussed as well as directions for further study. The article makes a useful contribution to the field given the dearth of research conducted on this topic in Ireland to date. 相似文献