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51.
Fahd Kiran Miah Shah J. Ahmed Khandakar Venkatraman Sitalakshmi Miao Yuan 《Education and Information Technologies》2021,26(4):4027-4048
Education and Information Technologies - This paper proposes an integrated research framework that takes advantage of the similarities of design science research (DSR) and Design-based research... 相似文献
52.
LI Q M 《天津大学学报(英文版)》2006,12(Z1)
In order to ensure the highest safety requirements, nuclear power plant structures (the containment structures, the fuel storages and transportation systems) should be assessed against all possible internal and external impact threats. The internal impact threats include kinetic missiles generated by the failure of high pressure vessels and pipes, the failure of high speed rotating machineries and accidental drops. The external impact threats may come from airborne missiles, aircraft impact, explosion blast and fragments. The impact effects of these threats on concrete and steel structures in a nuclear power plant are discussed. Methods and procedures for the impact assessment of nuclear power plants are introduced. Recent studies on penetration and perforation mechanics as well as progresses on dynamic properties of concrete-like materials are presented to increase the understanding of the impact effects on concrete containment structures. 相似文献
53.
This study examined the extent to which the quality of parent and peer attachments related to early adolescents' life satisfaction (LS), whether peer attachment served as a mediator between parent attachment and LS, and potential gender differences. A total of 587 middle school students in grades 6 through 8 participated. Although both parent and peer attachment positively related to LS, parent attachment was the stronger unique predictor. There was no significant difference between males and females in levels of parent attachment; however, females reported higher levels of attachment to peers. This study also found that early adolescents were more attached to their mothers than their fathers. Finally, peer attachment partially mediated the relationship between parent attachment and LS, but only for females. Implications for gender‐specific intervention programs are discussed. © 2008 Wiley Periodicals, Inc. 相似文献
54.
The design of a segmented-rod projectile is often simplified into an ideal one in theoretical analysis for the convenience of modeling of its performance. But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored. AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities, which can be used to guide the optimal design of weaponry segmented-rod projectiles. 相似文献
55.
Many engineering materials demonstrate dynamic enhancement of their compressive strength with the increase of strain-rate, which have been included in material models to improve the reliability of numerical simulations of the material and structural responses under impact and blast loads. The strain-rate effects on the dynamic compressive strength of a range of engineering materials which behave in hydrostatic-stress-sensitive manner were investigated. It is concluded that the dynamic enhancement of the compressive strength of a hydrostatic-stress-sensitive material may include inertia-induced lateral confinement effects, which, as a non-strain-rate factor, may greatly enhance the compressive strength of these materials. Some empirical formulae based on the dynamic stress-strain measurements over-predict the strain-rate effects on the compressive strength of these hydrostatic-stress-sensitive materials, and thus may over-estimate the structural resistance to impact and blast loads, leading to non-conservative design of protective structures. 相似文献
56.
INTRODUCTION Veselago (1968) showed that if both the permit- tivity ε and the magnetic permeability μ of a material are negative, the propagation direction of an elec- tromagnetic (EM) wave will be opposite to its energy flow direction. Such media are called left-handed materials (LHMs) since the electric field E, magnetic field H, and wave vector k in these media form a left-hand triplet of vectors, instead of a right-hand triplet observed in conventional materials. For a long time, … 相似文献
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This study assessed the differences in the emotional intelligence of gifted adolescent students and talented adolescent students in Bahrain. The sample consisted of 80 gifted adolescent students and 80 talented adolescent students in Grades 9 through 12. A multivariate analysis of variance (MANOVA) indicates that there were significant differences in emotional intelligence levels, as measured by the Bar-On Emotional Quotient Inventory, between gifted students and talented students in Bahrain in the direction of gifted students. There were differences between the gifted and the talented students in intrapersonal, adaptability, general mood subtest, and total emotional intelligence scores. Finally, gifted males had higher total emotional intelligence scores than gifted females; talented females had higher interpersonal scores than talented males. 相似文献
60.
The study examined whether schools for the deaf were providing services to assist parents in communicating with their children about sexuality (including sexual signs) and whether parents were involved in the sexuality education curriculum within their child's school. The Sexuality Curriculum Questionnaire for Educators of Students Who Are Deaf (Getch & Gabriel, 1998) was completed by 71 educators teaching sexuality curricula in schools for the deaf across the United States. Results indicated that parents were more likely to be involved in approval and development of their children's sexuality education than to receive assistance with sexuality education from the schools. Although the level of parental participation in curriculum development and approval is encouraging, the number of parents actually participating in curriculum development and approval remains low. 相似文献