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471.
Succinct data structures were designed to store and/or index data with a relatively small alphabet size, a rather skewed distribution and/or, a considerable amount of repetitiveness. Although many of them were developed to handle text, they have been used with other data types, like biological collections or source code. However, there are no applications of succinct data structures in the case of floating point data, the obvious reason is that this data type does not usually fulfill the aforementioned requirements. 相似文献
472.
In this work a procedure for obtaining polytopic λ-contractive sets for Takagi–Sugeno fuzzy systems is presented, adapting well-known algorithms from literature on discrete-time linear difference inclusions (LDI) to multi-dimensional summations. As a complexity parameter increases, these sets tend to the maximal invariant set of the system when no information on the shape of the membership functions is available. λ-contractive sets are naturally associated to level sets of polyhedral Lyapunov functions proving a decay-rate of λ. The paper proves that the proposed algorithm obtains better results than a class of Lyapunov methods for the same complexity degree: if such a Lyapunov function exists, the proposed algorithm converges in a finite number of steps and proves a larger λ-contractive set. 相似文献
473.
Pilar Fernandez-Calle Sandra Pelaz Paloma Oliver Maria Jose Alcaide Ruben Gomez-Rioja Antonio Buno Jose Manuel Iturzaeta 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(1):83-95
Introduction
Technological innovation requires the laboratories to ensure that modifications or incorporations of new techniques do not alter the quality of their results. In an ISO 15189 accredited laboratory, flexible scope accreditation facilitates the inclusion of these changes prior to accreditation body evaluation. A strategy to perform the validation of a biochemistry analyzer in an accredited laboratory having a flexible scope is shown.Materials and methods:
A validation procedure including the evaluation of imprecision and bias of two Dimension Vista analysers 1500 was conducted. Comparability of patient results between one of them and the lately replaced Dimension RxL Max was evaluated. All studies followed the respective Clinical and Laboratory Standards Institute (CLSI) protocols. 30 chemistry assays were studied. Coefficients of variation, percent bias and total error were calculated for all tests and biological variation was considered as acceptance criteria. Quality control material and patient samples were used as test materials. Interchangeability of the results was established by processing forty patients’ samples in both devices.Results:
27 of the 30 studied parameters met allowable performance criteria. Sodium, chloride and magnesium did not fulfil acceptance criteria. Evidence of interchangeability of patient results was obtained for all parameters except magnesium, NT-proBNP, cTroponin I and C-reactive protein.Conclusions:
A laboratory having a well structured and documented validation procedure can opt to get a flexible scope of accreditation. In addition, performing these activities prior to use on patient samples may evidence technical issues which must be corrected to minimize their impact on patient results. 相似文献474.
Peter Krustrup Werner Helsen Morten B. Randers Jesper F. Christensen Christopher MacDonald Antonio Natal Rebelo 《Journal of sports sciences》2013,31(11):1167-1176
Abstract Time-motion analyses and physiological measurements were performed to investigate the physiological demands of football referees (n = 15) and assistant referees (n = 15) in international games and to examine whether high-intensity running (HIR) correlates to the referees' ability to keep up with play. Total distance covered (10.27 ± 0.90 vs. 6.76 ± 0.83 km) and HIR (1.92 ± 0.58 vs. 0.97 ± 0.22 km) was higher (P < 0.05) for referees than assistant referees, while sprinting distance was not different. Referees covered 0.89 ± 0.37 km by backwards running and assistant referees covered 1.54 ± 0.66 km by sideways running. Mean heart rate was higher (P < 0.05) for referees than assistant referees (150 ± 3 vs. 123 ± 3 b.p.m.), whereas blood lactate was not different. Backwards/sideways running decreased (P < 0.05) from the first to the last 15-min period for referees (49%) and assistant referees (42%), whereas HIR was unaltered. HIR was inversely correlated with the five highest distances from infringements in both halves (r = ?0.60 and ?0.58, P < 0.05). In conclusion, international match officials carry out an important amount of HIR throughout games, while low-intensity and unorthodox running activities are reduced during games. Referees performing the most high-intensity work are better to keep up with play. The match activities differ significantly between referees and assistant referees, which should be considered in training and testing procedures. 相似文献
475.
Corrado Lupo Carlo Minganti Cristina Cortis Fabrizio Perroni Laura Capranica Antonio Tessitore 《Journal of sports sciences》2013,31(9):889-897
Abstract This study aimed to compare specific technical and tactical indicators of the team and centre forward role of Euro League, and Italian Serie A1, Serie A2, and Serie B men's water polo club competitions. A notational analysis was performed on 21 water polo matches to evaluate the occurrence of technical and tactical team and centre forward indicators, highlighting differences among championships according to chi-square analyses. Differences emerged for Counterattack (P < 0.001) and Power-Play (P < 0.001) possessions, Even (P < 0.001; Euro League: 3 ± 1, Serie A1: 3 ± 2, Serie A2: 3 ± 2, Serie B: 6 ± 4) and Power-Play (P = 0.001) goals, and exclusions and penalties (P = 0.008) of the team during Even possessions. Relatively to the role analyses, effects emerged for perimeter players playing events (P = 0.049), as well as for centre forwards' goals (P = 0.007) and exclusions and penalties (P < 0.001; Euro League: 8 ± 1, Serie A1: 6 ± 2, Serie A2: 6 ± 2, Serie B: 3 ± 2) occurring at the end of Even possessions. Therefore, in Euro League, and Italian Serie A1 and Serie A2, teams perform a high occurrence of Power-Play possessions following up an exclusion, especially achieved by the centre forward during Even possessions, while, in Italian Serie B, goals were mostly scored during Even possessions, with a relevant contribution from the centre forward role. 相似文献
476.
Tomás García-Calvo Francisco Miguel Leo Inmaculada Gonzalez-Ponce Pedro Antonio Sánchez-Miguel Athanasios Mouratidis Nikos Ntoumanis 《Journal of sports sciences》2013,31(18):1738-1750
AbstractIn this longitudinal study, we examined the extent to which perceived coach- and peer-created motivational climates are associated with athlete-group cohesion and satisfaction with participation among Spanish soccer players competing in the Third National Division. Multilevel modelling analyses showed that perceived coach-created task climate was positively related to perceived cohesion and players’ satisfaction with their participation within their team. Also, perceived peer-created task climate related positively to perceived cohesion. The results indicate the importance of considering peer-related aspects of the motivational climate in addition to considering the coach-related aspects of the motivational climate when examining motivational group dynamics in sport. 相似文献
477.
AbstractThis study analysed whether a significant relationship exists between the torque and muscle thickness and pennation angle of the erector spinae muscle during a maximal isometric lumbar extension with the lumbar spine in neutral position. This was a cross-sectional study in which 46 healthy adults performed three repetitions for 5 s of maximal isometric lumbar extension with rests of 90 s. During the lumbar extensions, bilateral ultrasound images of the erector spinae muscle (to measure pennation angle and muscle thickness) and torque were acquired. Reliability test analysis calculating the internal consistency (Cronbach's alpha) of the measure, correlation between pennation angle, muscle thickness and torque extensions were examined. Through a linear regression the contribution of each independent variable (muscle thickness and pennation angle) to the variation of the dependent variable (torque) was calculated. The results of the reliability test were: 0.976–0.979 (pennation angle), 0.980–0.980 (muscle thickness) and 0.994 (torque). The results show that pennation angle and muscle thickness were significantly related to each other with a range between 0.295 and 0.762. In addition, multiple regression analysis showed that the two variables considered in this study explained 68% of the variance in the torque. Pennation angle and muscle thickness have a moderate impact on the variance exerted on the torque during a maximal isometric lumbar extension with the lumbar spine in neutral position. 相似文献
478.
479.
Antonio J. Rojas Tejada Raquel M. Cruz del Pino Moshe Tatar Pablo Jiménez Sayáns 《European Journal of Psychology of Education - EJPE》2012,27(3):285-298
The present study focuses on the Temporary Classroom of Linguistic Adaptation program (TCLA program) in which specialist teachers (Spanish as a foreign language teachers—SFL teachers) teach Spanish to immigrants who are not proficient in the language. We suggest that support for immigrant students in Spanish schools should adopt a new inclusive educational approach. The present investigation is a preliminary attempt at characterizing the profiles of SFL teachers by assessing, simultaneously, five relevant variables (through cluster analysis): inclusive beliefs, teachers’ perceptions of student outcomes in TCLA program, general burnout, diversity-related teacher burnout, and years of teaching experience. Eighty-one SFL teachers from 132 schools in Spain (EU) were asked to complete a self-report questionnaire. Cluster analysis found two clearly differentiated groups: the larger one, Innovative SFL Teachers and the smaller, Traditional SFL Teachers. The Traditional SFL Teachers are characterized by more years of experience, lower inclusive beliefs scores, lower teachers’ perception of student outcomes in the TCLA program scores, and higher burnout scores as compared with the Innovative SFL Teachers. Moreover, Traditional SFL Teachers conceptualize their teaching role as a "teacher of Spanish" whereas Innovative SFL Teachers see themselves much more as playing a supportive role. 相似文献
480.
在一定意义上,历史唯物主义就是马克思主义。历史唯物主义可以作为三种理论:作为对人生和宇宙最一般理解的一种哲学方法;作为一种由于其展现一种特定的历史阶段而可以归结为某些法则的政治经济学评论;作为一种关于所有劳动阶级向社会主义迈进的必需的和能用的政治活动的解释和说明。马克思主义现在和将来都不是拘泥于马克思和恩格斯的著作之内的。马克思主义这个名称即便是现在也是一个有多向旨趣而且内容复杂的理论的象征和纲要。 相似文献