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排序方式： 共有588条查询结果，搜索用时 15 毫秒
551.
Set-Valued and Variational Analysis - In this paper, we provide a further study for nonconvex pseudomonotone equilibrium problems and nonconvex mixed variational inequalities by using global... 相似文献
552.
Journal of Optimization Theory and Applications - We propose a proximal point method for quasiconvex pseudomonotone equilibrium problems. The subproblems of the method are optimization problems... 相似文献
553.
We study the quantifier complexity and the relative strength of some fragments of arithmetic axiomatized by induction and minimization schemes for Δn+1 formulas. 相似文献
554.
John Settlage Malcolm B. Butler Julianne Wenner Lara K. Smetana Betsy McCoach 《School science and mathematics》2015,115(8):381-391
There is the tendency to explain away successful urban schools as indicative of the heroic efforts by a tireless individual, effectively blaming schools that underperform for a lack of grit and dedication. This study reports the development of a research instrument (School Science Infrastructure, or SSI) and then applying that tool to an investigation of equitable science performance by elementary schools. Our efforts to develop a science‐specific instrument to explore associations between school‐level variables and equitable science performance are informed by James Coleman's tripartite notion of social capital: the “wealth” of organizations is encompassed within their social norms, informational channels, and reciprocating relationships. Grounded in school effectiveness research and social capital theory, the instrument that we report on here is a valid and reliable tool to support meso‐level investigations of factors contributing to school variations in science achievement. 相似文献
555.
Lynne C. McArthur Lara Klass Andrew Eberhard Andrew Stacey 《International Journal of Mathematical Education in Science & Technology》2013,44(8):1041-1060
This article describes a qualitative study which was undertaken to improve the delivery methods and feedback opportunity in honours mathematics lectures which are delivered through Access Grid Rooms. Access Grid Rooms are facilities that provide two-way video and audio interactivity across multiple sites, with the inclusion of smart boards. The principal aim was to improve the student learning experience, given the new environment. The specific aspects of the course delivery that the study focused on included presentation of materials and provision of opportunities for interaction between the students and between students and lecturers. The practical considerations in the delivery of distance learning are well documented in the literature, and similar problems arise in the Access Grid Room environment; in particular, those of limited access to face-to-face interaction and the reduction in peer support. The nature of the Access Grid Room classes implies that students studying the same course can be physically situated in different cities, and possibly in different countries. When studying, it is important that students have opportunity to discuss new concepts with others; particularly their peers and their lecturer. The Access Grid Room environment also presents new challenges for the lecturer, who must learn new skills in the delivery of materials. The unique nature of Access Grid Room technology offers unprecedented opportunity for effective course delivery and positive outcomes for students, and was developed in response to a need to be able to interact with complex data, other students and the instructor, in real-time, at a distance and from multiple sites. This is a relatively new technology and as yet there has been little or no studies specifically addressing the use and misuse of the technology. The study found that the correct placement of cameras and the use of printed material and smart boards were all crucial to the student experience. In addition, the inclusion of special tutorial type sessions were necessary to provide opportunities to students for one-on-one discussion with both lecturer and other students. This study contributes to the broader understanding of distance education in general and future Access Grid Room course delivery in particular. 相似文献
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Klumpp C Lacerda L Chaloin O Da Ros T Kostarelos K Prato M Bianco A 《Chemical communications (Cambridge, England)》2007,(36):3762-3764
Cationic poly-N,N-dimethylfulleropyrrolidinium derivatives have been designed and synthesised to complex plasmid DNA for gene delivery. 相似文献
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Lara M Dayou F Launay JM Bergeat A Hickson KM Naulin C Costes M 《Physical chemistry chemical physics : PCCP》2011,13(18):8127-8130
The integral cross section of the S((1)D(2)) + H(2)(j = 0) → SH + H reaction has been measured for the first time at collision energies from 0.820 down to 0.078 kJ mol(-1) in a high-resolution crossed beam experiment. The excitation function obtained exhibits a non-monotonic variation with collision energy and compares well with the results of high-level quantum calculations. In particular, the structures observed in the lower energy part, where only a few partial waves contribute, can be described in terms of the sequential opening of individual channels, consistent with the theoretical calculations. 相似文献