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901.
In this paper, we present a functional variable method for finding periodic wave and solitary wave solutions of complex nonlinear evolution equations in mathematical physics and engineering sciences. The proposed technique is tested on the generalized Zakharov equation and higher-order nonlinear Schrödinger equations. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in applied mathematics. 相似文献
902.
Steven R. Wilson Patricia E. Gettings Lisa M. Guntzviller Elizabeth A. Munz 《Journal of Applied Communication Research》2013,41(4):409-431
Although scholars and service providers typically assume that parental self-efficacy (PSE) facilitates sensitive parenting, this study finds that the association between PSE and observer ratings of parents' sensitivity during free play actually is curvilinear. Parents (33 mothers, 5 fathers) from an intergenerational learning program serving low-income families completed the Self-Efficacy for Parenting Tasks Index and were videotaped during a 15-minute play period with their infant/toddler at program entry. Parents' self-reported PSE is positively, albeit weakly, associated with observer ratings of parental sensitivity from low to moderate levels of self-efficacy but inversely associated with sensitivity from moderate to high self-efficacy. Qualitative analyses show that mothers who report high PSE but are rated as low in sensitivity introduce toys when their child is already engaged, restrict their child's access to toys, physically manipulate their child, and violate their child's proximal space. Parenting education programs need to develop strategies for reaching parents who enter with high levels of confidence but lack knowledge of competent parenting practices. 相似文献
903.
Females and youth are frequently described as "special" populations in football literature, but together these two populations outnumber male players. What makes females "special" is that they tend to eat less when training and competing than their male counterparts, leading to lower intakes of energy, carbohydrate, and some nutrients. Youth football players are special in regard to energy and nutrient requirements to promote growth and development, as well as to fuel sport. There is limited research on the dietary habits of these two populations, but the available literature suggests that many female and youth players need to increase carbohydrate intake, increase fluid intake, and develop dietary habits to sustain the demands of training and competition. 相似文献
904.
905.
V. B. Saputra S. K. Ong A. Y. C. Nee 《上海大学学报(英文版)》2014,(3):222-230
This paper presents a calibration method for parallel manipulators using a measurement system specially installed on an external fixed frame. The external fixed frame is important as an error reference for calibration in certain operations, such as in the configuration of a parallel manip- ulator functioning as a machine tool where the workpiece is fixed to a worktable. The pose of the end-effector is mea- sured using three digital indicators installed on the external fixed frame. To enable measurement, the end-effector is assumed to be a plane large enough that all digital indicators could touch. The error is defined as the difference between the theoretical and actual readings of the digital indicators. The geometric parameters of the parallel manipulator are optimized to minimize this error. This calibration method is low cost and feasible for compensating geometric parameter errors for a parallel manipulator. Optimal pose selection for the calibration is achieved using a swarm intelligence search algorithm. The method is implemented on a prototype of a six degrees-of-freedom (DOFs) Gough-Stewart platform constructed to function as a machine tool. 相似文献
906.
Ruth Elizabeth Tkachyk 《Interchange》2013,44(1-2):15-24
Educating students with special needs in inclusive settings has become a priority for westernized governments as they strive to create more inclusive societies. While recognizing the societal benefits of inclusion, teachers and parents question whether or not implementation of full inclusion will come at the expense of learners’ individual needs. This is particularly true for students with cognitive disabilities moving into the content-rich, peer-dominated environment of secondary school. It will be maintained within this article that there remains a need for segregated classrooms where students with mild cognitive disabilities can receive the specialized programming and supports that they require in a low-stress environment. Furthermore, educators should continue to prioritize the learning needs of all students with disabilities when contemplating full inclusion. Modeling an inclusive society should not mean inclusion at all costs, but considering what’s best for each student and recognizing that one size does not fit all. 相似文献
907.
Meng‐Tzu Cheng Leonard Annetta Elizabeth Folta Shawn Y. Holmes 《International Journal of Science Education》2013,35(2):299-319
Drugs and the Brain: A Serious Game, a prototype museum exhibit, was designed to employ virtual models of the brain into a video game format. It was done to create a fun and engaging way of conveying knowledge and concepts about neuroscience, as well as the impact of methamphetamine abuse on the brain. The purpose of this study is to evaluate this prototype exhibit that promises to educate participants from various age, ethnicity, and gender backgrounds, and to establish a stronger concept of drug abuse prevention among children. A quantitative methodology using the pre‐ and post‐experimental designs was conducted on 175 museum visitors. A series of two‐sample paired t‐tests and subsequent ANOVAs were performed to examine the difference between pre‐ and post‐tests and to determine if there was a difference in the results in age, gender, ethnicity, and race. Results showed that both the understanding and attitudes of the participants toward the impact of methamphetamine abuse on the brain improved significantly (p < 0.01). 相似文献
908.
This study examined the relations among maternal socialization of positive affect (PA), adolescent emotion regulation (ER), and adolescent depressive symptoms. Two hundred early adolescents, 11-13 years old, provided self-reports of ER strategies and depressive symptomatology; their mothers provided self-reports of socialization responses to adolescent PA. One hundred and sixty-three mother-adolescent dyads participated in 2 interaction tasks. Adolescents whose mothers responded in an invalidating or "dampening" manner toward their PA displayed more emotionally dysregulated behaviors and reported using maladaptive ER strategies more frequently. Adolescents whose mothers dampened their PA more frequently during mother-adolescent interactions, and girls whose mothers reported invalidating their PA, reported more depressive symptoms. Adolescent use of maladaptive ER strategies mediated the association between maternal invalidation of PA and early adolescents' concurrent depressive symptoms. 相似文献
909.
OBJECTIVE: The prevalence of childhood sexual abuse among Latino adult men who have sex with men who live in the US was estimated because a history of childhood sexual abuse increases HIV sexual risk behaviors and other negative health outcomes in adulthood. METHOD: The Urban Men's Health Study is a random-digit telephone probability survey of 2881 adult men who have sex with men (MSM) aged 18 years or older residing in San Francisco, New York, Los Angeles, and Chicago. Self-reported history of childhood sexual abuse was the main outcome measure gathered from 2692 MSM. RESULTS: A significantly higher proportion of Latino MSM reported sexual abuse before age 13 (22%) than did non-Latino MSM (11%). CONCLUSIONS: Latino MSM are twice as likely to report a history of childhood sexual abuse than are non-Latino MSM. Given the association between childhood sexual abuse and increased risk for HIV and other negative health outcomes, health providers must remain vigilant to the possibility of childhood sexual abuse histories among their Latino patients. 相似文献
910.
In recent years, evolutionary and meta-heuristic algorithms have been extensively used as search and optimization tools in various problem domains, including science, commerce, and engineering. Ease of use, broad applicability, and global perspective may be considered as the primary reason for their success. The honey-bee mating process has been considered as a typical swarm-based approach to optimization, in which the search algorithm is inspired by the process of real honey-bee mating. In this paper, the honey-bee mating optimization (HBMO) algorithm is presented and tested with a nonlinear, continuous constrained problem with continuous decision and state variables to demonstrate the efficiency of the algorithm in handling the single reservoir operation optimization problems. It is shown that the performance of the model is quite comparable with the results of the well-developed traditional linear programming (LP) solvers such as LINGO 8.0. Results obtained are quite promising and compare well with the final results of the other approach. 相似文献