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201.
The aim of the present work was to analyze the influence of self-controlled task difficulty on motor learning. Participants had to intercept three targets falling at different velocities by displacing a stylus above a digitizer Task difficulty corresponded to racquet width. Half the participants (self-control condition) could choose the racquet width at the beginning of each trial. Each was paired with a participant from the yoked group. The self-control condition resulted in better performances and accuracy during immediate and delayed retention tests. These results confirm the advantage of a self-control condition on motor learning. They are discussed with reference to the challenge point hypothesis (Guadagnoli & Lee, 2004).  相似文献   
202.
We prove in this paper the existence and uniqueness of mild solutions to some functional differential and functional integro-differential equations with infinite delay in Banach spaces which approach almost automorphic functions at infinity. We also discuss the existence of S-asymptotically ω-periodic mild solutions. The results are new.  相似文献   
203.
This paper proposes a new sliding mode observer for fault reconstruction, applicable for a class of linear parameter varying (LPV) systems. Observer schemes for actuator and sensor fault reconstruction are presented. For the actuator fault reconstruction scheme, a virtual system comprising the system matrix and a fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix is instrumental in simplifying the synthesis procedure to create the observer gains to ensure a stable closed-loop reduced order sliding motion. The ‘output error injection signals’ from the observer are used as the basis for reconstructing the fault signals. For the sensor fault observer design, augmenting the LPV system with a filtered version of the faulty measurements allows the sensor fault reconstruction problem to be posed as an actuator fault reconstruction scenario. Simulation tests based on a high-fidelity nonlinear model of a transport aircraft have been used to demonstrate the proposed actuator and sensor FDI schemes. The simulation results show their efficacy.  相似文献   
204.
PurposeThe purpose of this study was to compare established methods with newly-developed methods for estimating the total energy expenditure (TEE).MethodsThe study subjects comprised 46 individuals, including 16 middle-aged men (mean age 51.4 years), 14 middle-aged women (mean age 49.9 years) and 16 young women (mean age 19.1 years). The TEE was estimated from 24-h heart rate (HR) data using newly-developed software (MoveSense HRAnalyzer 2011a, RC1, Suunto Oy, Vantaa, Finland), and was compared against the TEE determined using doubly labeled water (DLW). Agreement between the two methods was analyzed using Bland and Altman plots.ResultsThe HR method yielded similar TEE values as the DLW method at the group level, with an average of 8.6 kcal/day in the difference in the mean, but with large individual variations. Forty-four (96%) out of 46 subjects fell within ±2SD of the mean difference in TEE comparisons, and there was no tendency towards under- or over-estimation.ConclusionOur results indicate that the current software using HR analysis for the estimation of daily TEE needs further development for use with free-living individuals.  相似文献   
205.
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria.  相似文献   
206.
Nowadays, some virtual museums include 3D room scenes to show the models of its pieces, just like in real museums. Nevertheless, the generation and maintenance of this kind of scenes is generally difficult and should be done by an expert. For example, any change such as including a new piece or modifying the position of an existing fragment usually requires a different design and the creation of a new scene. In this paper we present a case study on the development of a web-based application to automatize this process. To this end, a database to store both graphic and non-graphic information about the pieces, and some 3D rooms to show them has been created. The designed scenes only contain some pieces of furniture to exhibit the fragments, which will be subsequently included. Thus, when a room is loaded in the web page, its associated pieces are obtained through a query in the database and its models are dynamically included in the original scene. Therefore, the position changes or the inclusion of new pieces are not performed in the 3D model, but in the database. Our application makes the transmission of the knowledge to the general public easier because any new discovered piece can be included in a existing museum effortlessly.  相似文献   
207.
We review empirical research on English language learners (ELLs) who struggle with reading and who may have learning disabilities (LD). We sought to determine research indicators that can help us better differentiate between ELLs who struggle to acquire literacy because of their limited proficiency in English and ELLs who have actual LD. We conclude that more research is warranted to further elucidate the strengths and learning needs of subgroups of underachieving ELLs, to help us determine who should qualify for special education, and to clarify why some ELLs who do not have LD still struggle with language and literacy acquisition. Future research should account for the complexities involved in becoming literate in another language and focus more on cultural and contextual factors that affect student achievement.  相似文献   
208.
Four-month-old infants were habituated with an upright or an upside-down face. Eye-movement recordings showed that the upright and upside-down faces were not explored the same way. Infants spent more time exploring internal features, mainly in the region of the nose and mouth, when the face was upright. They also alternated as frequently between the face's internal features (eyes vs. nose/mouth) as between external and internal features. When the face was upside down, the infants spent half of their time exploring external features, and preferentially alternated between external features and internal features. The main effect of inversion was a decrease of the looking time to the nose/mouth region and of the number of shifts between the eye region and the nose/mouth region.  相似文献   
209.
Many factors go into the decision of selecting a university, ranging from the overall costs and the programme of study to the institute’s reputation; however, accommodation while at university and proximity of the university to one’s permanent abode also play important roles in this decision-making process. Thus, first-year students experience different stages of separation from their prior networks depending on their individual situations. The results of this Ontario (Canada) 2012 study add to prior research by indicating that separation of students’ living arrangements and distance from home impact on transition and incorporation variables, which influenced students’ adaptation to university.  相似文献   
210.
This study explored the early development of expert athletes compared to a group of athletes that did not achieve an expert level of performance despite being involved in youth events with their national squads. In particular, the activities, training patterns, and psychosocial influences that characterized their paths in competitive sports were examined. Male and female participants (N?=?42) from different sports were interviewed. Overall, athletes showed several commonalities. However, experts were selected to national squads later and also started thinking about investing in becoming elite athletes later. Non-experts revealed more parental pressure and less individual training with coaches.  相似文献   
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