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1.
The paper focuses on the importance of distinguishing between decoding and comprehension skills in reading. This distinction can also be applied to the study of precursors of reading and of the first phases of reading acquisition. The reconsideration of a 15-year research program shows evidence and implications of such a dissociation. In particular, the paper reviews psychometric research concerning reading performance in first and second grade, research on precursors of reading, the effects of early programs devoted to develop reading abilities. Decoding and comprehension reading components appear at least partially separated, related to different underlying cognitive abilities, differently sensitive to enrichment programs.  相似文献   
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Although most of the queries submitted to search engines are composed of a few keywords and have a length that ranges from three to six words, more than 15% of the total volume of the queries are verbose, introduce ambiguity and cause topic drifts. We consider verbosity a different property of queries from length since a verbose query is not necessarily long, it might be succinct and a short query might be verbose. This paper proposes a methodology to automatically detect verbose queries and conditionally modify queries. The methodology proposed in this paper exploits state-of-the-art classification algorithms, combines concepts from a large linguistic database and uses a topic gisting algorithm we designed for verbose query modification purposes. Our experimental results have been obtained using the TREC Robust track collection, thirty topics classified by difficulty degree, four queries per topic classified by verbosity and length, and human assessment of query verbosity. Our results suggest that the methodology for query modification conditioned to query verbosity detection and topic gisting is significantly effective and that query modification should be refined when topic difficulty and query verbosity are considered since these two properties interact and query verbosity is not straightforwardly related to query length.  相似文献   
3.
Abstract

Elite-standard rowers tend to use a fast-start strategy followed by an inverted parabolic-shaped speed profile in 2000-m races. This strategy is probably the best to manage energy resources during the race and maximise performance. This study investigated the use of virtual reality (VR) with novice rowers as a means to learn about energy management. Participants from an avatar group (n = 7) were instructed to track a virtual boat on a screen, whose speed was set individually to follow the appropriate to-be-learned speed profile. A control group (n = 8) followed an indoor training programme. In spite of similar physiological characteristics in the groups, the avatar group learned and maintained the required profile, resulting in an improved performance (i.e. a decrease in race duration), whereas the control group did not. These results suggest that VR is a means to learn an energy-related skill and improve performance.  相似文献   
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This paper proposes a model to assess the level of maturity in Virtual Communities of Practice (VCoPs). The model is based on a theoretical construction attained from the analysis of previous frameworks proposed in literature. Using this construction, we have proposed eight main organizational, managerial and technological levers to improve the performance of VCoPs. Additionally, the model presents the analysis of four performance metrics obtained from these VCoP management levers. The model presented can be used as a benchmarking tool for analysing how companies perform in their management of VCoPs. After developing the model, we applied it to a benchmarking study of four global oil and gas companies. Our results include a performance comparison among these companies as well as the main practices and technologies they use to achieve success in the management of VCoP.  相似文献   
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Abstract

Although motorcycling performance strongly depends on the characteristics of the motorcycles and capabilities of the riders, little information is available on the physiological profiles of riders. The aim of this study was to evaluate the physical load of official international men's road-race motorcycling competitions. Data were obtained from 34 male riders during the 2005 European Road-Race Motorcycling Championship (categories classified by size of engine: 125 GP, 250 GP, and 600 cc) during free practices, qualifying sessions, and official races. Participants' heart rates were recorded and blood lactate concentrations determined. During races, heart rates were most often above 90% of maximum heart rate (frequency of occurrence: 125 GP = 92.9%, s = 5.3; 250 GP = 93.6%, s = 7.3; 600 cc = 93.2%, s = 10.2). The heart rate distribution during riding showed main effects between phases of competition, engine sizes, and different portions of the race (P < 0.001). No difference was observed between riders on and not on the podium at the end of the race. Peak blood lactate concentrations after the qualifying sessions (5.2 mmol · l?1, s = 1.2) and official races (6.0 mmol · l?1, s = 2.1) were higher (P < 0.001) than at baseline. The present results show that road-race motorcycling imposes a high load on the riders, who should possess adequate fitness to maintain high-speed rides and minimize the effects of fatigue during competition.  相似文献   
8.
A survey to determine attitudes toward end-user searching was made at Loyola University's Medical Center Library using MEDIS, an online full-text and bibliographic medical retrieval system. One hundred forty-one completed questionnaires were analyzed for this report. Information was collected on user familiarity with computers, end-user training, system use, mechanics of searching, and attitudes toward future use. Computer familiarity was highest among the faculty users. Ninety percent of the respondents saw librarians as a crucial agent in training and in providing end-user assistance. Respondents identified five major reasons for using the system: helpfulness, convenience, time savings, rapid feedback, and presentation of needed information. Searching the MEDLINE database rather than the full-text database was the search method of choice. Continued use of both mediated and end-user searching was intended by most of the respondents. Survey results support a perceived need for end-user searching and confirmed recommendations of the Association of American Medical Colleges on medical information science skills.  相似文献   
9.
Heart rate and blood lactate concentration of male road-race motorcyclists   总被引:1,自引:1,他引:0  
Although motorcycling performance strongly depends on the characteristics of the motorcycles and capabilities of the riders, little information is available on the physiological profiles of riders. The aim of this study was to evaluate the physical load of official international men's road-race motorcycling competitions. Data were obtained from 34 male riders during the 2005 European Road-Race Motorcycling Championship (categories classified by size of engine: 125 GP, 250 GP, and 600 cc) during free practices, qualifying sessions, and official races. Participants' heart rates were recorded and blood lactate concentrations determined. During races, heart rates were most often above 90% of maximum heart rate (frequency of occurrence: 125 GP = 92.9%, s = 5.3; 250 GP = 93.6%, s = 7.3; 600 cc = 93.2%, s = 10.2). The heart rate distribution during riding showed main effects between phases of competition, engine sizes, and different portions of the race (P < 0.001). No difference was observed between riders on and not on the podium at the end of the race. Peak blood lactate concentrations after the qualifying sessions (5.2 mmol . l(-1), s = 1.2) and official races (6.0 mmol . l(-1), s = 2.1) were higher (P < 0.001) than at baseline. The present results show that road-race motorcycling imposes a high load on the riders, who should possess adequate fitness to maintain high-speed rides and minimize the effects of fatigue during competition.  相似文献   
10.
In this paper, we illustrate the development of a realistic simulation of a humanoid robot model in a virtual environment using USARSim (Urban Search and Rescue Simulator). USARSim provides an accurate 3D simulation of a virtual environment with a detailed rendering and a realistic physics. Moreover, USARSim allows users to observe the virtual environment from different views. One of these is the egocentric view, which can simulate the camera mounted on the robot. The small humanoid robot presented in this work is Robovie-M, developed by VStone Ltd. (Japan). This robot is used by our team Artisti in the RobotCup soccer competitions.Reported experiments compare the behaviors of a real robot and of its virtual model, when controlled by the same control software to asses the possibility to faithfully simulate a robot with 22 degrees of freedom in USARSim. Moreover, we discuss the possibility to close the control loop of the robot in simulation, by simulating also the main robot sensor, i.e. the camera.The experiments show that USARSim, despite being a simple simulator based on a low cost computer game, provides an accurate enough simulation of the physics and a realistic rendering of the 3D scene enabling a faithful simulation of a small humanoid robot at low cost. Thus, one can entirely test the robot software modules in the simulation (namely: the motion control modules, the vision system modules and, by closing the robot control loop in simulation, the behavior and behavior-selection modules).  相似文献   
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