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991.
二次规划的惯性控制算法要求初始可行点的工作集相应的既约海赛阵正定,为此,计算时常需要添加若干人工约束,而添加的人工约束过多必然影响计算效率。本讨论了使添加的人工约束个数是最少的策略。 相似文献
992.
试论高等职业教育实践教学体系与理论教学体系 总被引:19,自引:0,他引:19
本文从高等职业教育实践教学体系和理论教学体系的内涵、作用出发,阐明了高等职业教育实践教学体系和理论教学体系的关系。并用实例予以说明。 相似文献
993.
Exploring Learners’ Conceptual Resources: Singapore A Level Students’ Explanations in the Topic of Ionisation Energy 总被引:1,自引:0,他引:1
Keith S. Taber Kim Chwee Daniel Tan 《International Journal of Science and Mathematics Education》2007,5(3):375-392
This paper describes findings from a study to explore Singapore A-level (Grades 11 and 12, 16–19 yr old) students' understanding
of ionisation energy, an abstract and complex topic that is featured in school chemistry courses. Previous research had reported
that students in the United Kingdom commonly use alternative notions based on the perceived stability of full shells and the
‘sharing out’ of nuclear force, but that such ideas tend to be applied inconsistently. This paper describes results from the
administration of a two-tier multiple-choice instrument, the ionisation energy diagnostic instrument, to find (1) whether
A-level students in Singapore have similar ways of thinking about the factors influencing ionisation energy as reported from
their A-level counterparts in the UK; and (2) how Singapore A-level students explain the trend of ionisation energy across
different elements in Period 3. The results indicate that students in Singapore use the same alternative ideas as those in
the UK, and also a related alternative notion. The study also demonstrates considerable inconsistency in the way students
responded to related items. The potential significance of the findings to student understanding of complex topics across the
sciences is considered. 相似文献
994.
挖掘大昨村落文化特色,开辟乡村旅游市场可以推动大昨社会经济的发展。大昨村的自然生态、宗族意识、宗教信仰、民俗风情等具有明显的海洋文化特色,大昨村落文化特色的生成是与其历史积淀、地理条件息息相关的。在乡村游日益受到重视的今天,大昨村要进一步保护历史文化资源,开发文化特色品牌,从而凭借内在的文化优势走出一条体现地方特色的现代化道路。 相似文献
995.
Aik-Ling Tan Peter Peng Foo Lee Yin Hong Cheah 《Asia Pacific Journal of Education》2017,37(4):453-471
AbstractThis study examines the verbal interactions among a group of pre-service teachers as they engaged in scientific discussions in a medicinal chemistry course. These discussions were part of the course that encompassed an explicit instruction of scientific argumentation structures as well as an applied component, whereby the pre-service teachers learned the content of medicinal chemistry through cases developed using the strategy of competing theories. By adopting a case study approach using sociocultural framework of learning, we examined the interactions between the pre-service teachers using video data. We describe 12 possible forms of interactions during discussions – (1) seeking clarification, (2) figuring out loud, (3) sharing information, (4) agreement, (5) asking questions, (6) providing explanations, (7) raising strategic and procedural issues, (8) stating claims, (9) disagreement, (10) sharing perspectives, (11) offering alternatives, and (12) persuasion. The pre-service teachers engaged in figuring out aloud and seeking clarifications frequently, and used persuasion least in their discussions. To clarify their ideas and thoughts, pre-service teachers commonly rebut their counterparts and used warrants to support their own assertions. A similar pattern was also observed when figuring their thoughts out loud. Our findings suggest that pre-service teachers were able to carry out rebuttals in the argumentation process. However, the quality and function of their rebuttals can be improved by deepening their understanding of the subject matter knowledge and the science argumentation structure. Implications are discussed. 相似文献
996.
介绍了ISP(In-System Progammability,在系统可编程)器件,及ISP器件用于数字电路实践教学的方法。 相似文献
997.
998.
谭惠苓 《辽宁广播电视大学学报》2001,(3):39-41
加强高校教职工的思想政治工作是促进学校改革和发展的需要.校务公开正是新时期加强高校思想政治工作的新方法和新途径.为此,要明确校务公开的意义、内容及形式,研究探讨校务公开与思想政治工作的相互关系,进而加大校务公开的力度,增强思想政治工作的深度. 相似文献
999.
Transition metal-doping could effectively extend the light response range of TiO _2 photocatalysts from the ultraviolet(UV)to the visible region.Co-doped brookite titanium dioxide(Co–TiO_2)photocatalysts were synthesized via the hydrothermal method with titanium tetrachloride as the raw material and cobalt chloride hexahydrate as the dopant.The prepared Co–TiO_2 photocatalysts were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS)and UV–Vis diffuse reflectance spectroscopy(UV–Vis DRS).The photocatalytic activities of Co–TiO _2 photocatalysts were evaluated by photocatalytic degradation of isopropanol alcohol(IPA),a typical volatile organic compound(VOC),under visible light.The influences ofdifferent Co doping rates,initial concentrations of IPA gas and the amounts of photocatalyst addition were also studied.At the same time,the enhancement mechanism ofcobalt ions as a trap for photogenerated holes was discussed.Thus,we found the optimum doping rate,initial concentration of IPA gas and amount of photocatalyst to add.The results show that the mesoporous Co–TiO _2 photocatalysts possess smaller size particles,larger specific surface area,lower forbidden bandgap energy(Eg)and better photocatalytic activity than pure brookite TiO _2.When the doping of Co was 7% by mass,the initial concentration ofIPA gas was 1.0×10~(-6 )mol/L and the addition of Co–TiO_2 photocatalysts was 50 mg,the best photocatalytic activity was achieved.Furthermore,the degradation rate ofIPA was up to 91%,which shows great potential for waste water treatment. 相似文献
1000.
无论变化与统一、对比与调和、节奏与韵律、放射与回旋,都表现了一种秩序性,秩序是装饰之美的尺度。秩序是装饰之美的内在尺度。秩序代表着和谐,代表着变化以及变化后的统一,它始终与稳定和永恒性相联系。 相似文献