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91.
F. Q. Jing 《高压研究》2013,33(5-6):759-765
Abstract In this paper, several recent activities on shock wave research for engineering physics performed in China will be presented as the supplement of author's previous report of Ref. 1. 相似文献
92.
高分子物理是高分子材料相关专业的专业基础课,内容丰富,章节间关系复杂,课程主线往往不容易把握。本文从运动对高聚物性质(性能)的决定性作用角度,提出了构建高分子物理课程知识体系的观点:在高分子结构部分,充实原子、键等部分作用的论述,完善高分子结构划分的层次;明确高分子不同结构层次都具有运动与变化能力的认知,重点突出不同高分子结构运动、变化的特征和规律;根据根据每一个结构层次运动特征,综合理解结构、结构的变化对高分子性能的影响。 相似文献
93.
In the present investigation we define a new class of meromorphic functions on the punctured unit disk △*:= {z ∈ C : 0 < |z| < 1} by making use of the generalized Dziok-Srivastava operator H l m [α1 ]. Coefficient inequalities, growth and distortion inequalities, as well as closure results are obtained. We also establish some results concerning the partial sums of meromorphic functions and neighborhood results for functions in new class. 相似文献
94.
Jörg Fliege Konstantinos Kaparis Banafsheh Khosravi 《European Journal of Operational Research》2012,217(2):233-240
Operations research techniques have been used in the space industry since its infancy, and various competing methods and codes, with widely varying characteristics, have been used over time. This survey is intended to give an overview of current application cases of different operations research techniques and methodologies in the domain of space engineering and space science. 相似文献
95.
Matthias Otto Müller Stefan N. Groesser Silvia Ulli-Beer 《European Journal of Operational Research》2012,216(2):495-502
Collaborative research, defined as research involving actors participating in the problem situation under study, has an important role in operational research, strategic management and systems thinking. In a recent study, we found that a strong organizational focus incorporated into many soft operational research (OR) approaches is inadequate for studying societal problem situations, which are fragmented and have no clear boundary. Specifically, we failed to find a process of identifying individuals that is capable of representing the perspectives of actors and sufficient for research into societal problem situations. We found no clear terminology accounting for ontological differences between actors, individuals representing them and conceptual representations of acting entities. In response to this gap in the literature, we propose terminology that differentiates among actors (individuals or collective entities in the real world), experts (individuals capable of representing the perspective of an actor) and agents (ideal-typical representations of actors). Based on this terminology, we propose an iterative method to guide the assembly of an expert group to undertake collaborative research into societal problem situations. To demonstrate the application of our method, we present selected insights from our study in an electronic supplement. 相似文献
96.
97.
In this paper, as a first step to study the global structure of solution, we treat a class of reaction–diffusion systems with competitive interaction, and discuss a uniqueness theorem of radially symmetric solutions for the system. To do this, the comparison principle and the shooting method are employed, and the spatial profile is investigated. 相似文献
98.
Mohammed Larbi Labbi 《Mathematische Nachrichten》2015,288(4):402-411
The Weitzenböck curvature operators are the curvature terms of order zero that appear in the well‐known classical Weitzenböck formula. In this paper, we use the formalism of double forms to prove a simple formula for these operators and to study their geometric properties. 相似文献
99.
We consider the following system of fractional differential equations where is the Riemann‐Liouville fractional derivative of order α,f,g : [0,1] × [0, ∞ ) × [0, ∞ ) → [0, ∞ ). Sufficient conditions are provided for the existence of positive solutions to the considered problem. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
100.