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排序方式: 共有919条查询结果,搜索用时 15 毫秒
861.
862.
Juan J. Ley-Rosas Luis E. González-Jiménez Alexander G. Loukianov Jorge E. Ruiz-Duarte 《Journal of The Franklin Institute》2019,356(5):2559-2581
In this work, considering the roll dynamics and actuator dynamics, an observer-based control scheme for a vehicle is proposed. The proposal considers a nonlinear higher order sliding mode observer to estimate unmeasurable lateral velocity, roll angle and roll velocity. Using the observer information, a controller based on block control with sliding mode technique is designed for the reference trajectory tracking of the lateral and yaw velocities of the vehicle. The stability of the complete closed-loop system including zero dynamics is analyzed. The effectiveness of the proposed scheme is demonstrated through CarSim simulations. 相似文献
863.
About two thirds of adults in Germany are overweight or obese. While an increase in the consumption of high-calorie food is considered the main cause, the influence of various forms of sedentary activities is still controversially discussed. The aim of the present study is to compare the body composition of hobby gamers with reference data collected throughout Germany and to examine the effects of intensive use of computer games (gaming) on body composition. A total of 68 male participants of a computer game event aged 18–46 years (27.9 years; 180.1?cm; 83.5?kg; BMI 25.7) were examined for fat mass, body cell mass, extracellular mass, body water and phase angle using bioelectrical impedance analysis (BIA, Nutriguard MS type, data input). Ten test persons were retested by means of segmental 8?electrode BIA after a 24?h interval during their visit to the event. As a reference sample, data from 278 male adults of the same age (27.9 years, 179.4?cm; 78.8?kg; BMI 24.5) were collected in 168 locations throughout Germany. The hobby gamers reported on average 37.1?h screen media usage per week. Compared to the reference sample, they showed a slightly higher body cell mass index (p?<?0.01, T?=?4.07), but no differences in fat mass index (p?=?0.96, T?=?0.05) and phase angle (p?=?0.90, T?=?0.12). A significant increase in body water (T0: 48.2?l, T0+24?h: 49.3?l; p?=?0.04, T?=?2.39) and decrease in the phase angle of the lower extremities (T0:?7.40, T0+24?h: ?6.85; p?<?0.01, T?=?5.40) was observed in the 24?h retest. Compared to the reference data collected throughout Germany, hobby gamers show no differences in health-relevant parameters of body composition. Nevertheless, after intensive gaming, a short-term increase in the amount of extracellular water in the lower extremities was found. Due to these disturbances in the water balance, the consequent execution of movement breaks during gaming is important. 相似文献
864.
Alexander Maurits 《国际体育史杂志》2018,35(1):27-42
AbstractThe sport movement was consolidated in Sweden during the first years of the twentieth century and grew rapidly from the 1920s and onward. Preceding and during these events, the Church of Sweden – the Lutheran state church – was losing its axiomatic position within Swedish society and church attendance was decreasing. In this situation, many perceived the sports movement as a rival to the church or even saw sport as a new religion. However, as the sport movement grew, prominent representatives within the Church of Sweden and other Christian denominations adopted a more pragmatic view of the sports movement in order to appeal to people outside the ranks of the church, especially male youth. The sport field soon became a missionary field. The aim of the current essay is to account for the collaborative as well as the sceptical voices not only in the Church of Sweden, but also within the substantial Swedish revival movements, i.e. the Pentecostal movement and the Mission Covenant Church of Sweden. Further, these events will be analyzed from a gender perspective, discussing what was simultaneously perceived as a secularization and feminization of Swedish Christianity. 相似文献
865.
Philosophical Implications of Inflationary Cosmology 总被引:1,自引:0,他引:1
866.
867.
Cross-hierarchical interconnectivity is a social process of transmission and alignment of previously separated pieces of knowledge from idiosyncratic contexts of individuals at different hierarchical levels in an organisation. This paper advocates that the management of interconnectivity can contribute to organisational competitiveness, especially in terms of adaptability, innovation, and cohesion. Based on the parameters of mode, actor's culture, time, direction, type of knowledge, and medium, a portfolio of interconnectivity is suggested and the core forms and mechanisms of interconnectivity, which are represented in the portfolio matrix, are discussed in depth. Finally, the specific culture of corporate executives and how it can be improved in order to encourage interconnectivity is analysed. 相似文献
868.
Alexander Schill Thomas Springer und Thomas Ziegert 《Informatik - Forschung und Entwicklung》2001,16(4):200-212
Zusammenfassung. Die Integration mobiler Rechner in bestehende Netze erfordert eine umfassende Unterstützung. Die Hauptgründe dafür sind die
Vielfalt der eingesetzten Technologien sowie fehlende Konzepte in den bestehenden Systemen. In diesem Artikel werden M?glichkeiten
zur system- und anwendungsseitigen Unterstützung mobiler verteilter Systeme diskutiert. Nach einer kurzen Einführung in die
Problemstellungen des Forschungsgebietes werden Ans?tze für eine systemseitige Unterstützung mobiler Anwendungen und Dienste
anhand einer Softwareplattform beschrieben. Danach wird ein Modell zur Aufteilung mobiler Anwendungen vorgestellt, das verschiedene
system- und anwendungsseitige Unterstützungsmechanismen integriert. Abschlie?end wird das Modell zu einem Ansatz auf Basis
von Software-Komponenten verallgemeinert. Die Darstellung erfolgt anhand von Beispielsystemen, an deren Entwicklung die Autoren
ma?geblich beteiligt waren und sind.
Eingegangen am 31. Januar 2001 / Angenommen am 6. September 2001 相似文献
869.
Herbert A. Lubs Mark Rabin Esther Feldman Bonnie J. Jallad Alexander Kushch Karen Gross-Glenn Ranjan Duara R. C. Elston 《Annals of dyslexia》1993,43(1):44-60
In addition to providing information on the inheritance of dyslexia, the present study of eleven three-generation families
has provided a unique opportunity to compare affected and unaffected family members at all ages. The data presented here are
based on pedigree information, a questionnaire administered to all participating family members in relation to sex ratio,
handedness, the severity of dyslexia by sex, pre- and perinatal complications, medical complications, years of education and
earning ability, and a battery of standardized tests to define the presence or absence of dyslexia. The pattern of inheritance
was consistent with the postulated autosomal dominant mode of inheritance and penetrance was found to be > 90 percent. Of
73 individuals determined to have a gene leading to dyslexia, seven were classified as obligate carriers and six as compensated
adults who had no current symptoms or diagnostic evidence of dyslexia. The sex ratio (1.06) was not different from the expected
ratio of 1.04. Left-handedness, major pre- and perinatal complications, and autoimmune disorders and allergy were not more
common in dyslexics than non-dyslexics. The number of years of education and average income were similar in affected and unaffected
family members. Compensated adults and obligate carriers were similar to unaffected family members in each of these parameters. 相似文献
870.