检索结果-南通市图书馆

Optical Design of TIR Led Secondary Optics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optical Design of TIR Led Secondary Optics

第11届粤港机械电子工程技术与应用研讨会

作者： TO,S. jIANG,j.b. Advanced Optics Manufacturing Centre Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic University

＜正＞Secondary Optics are critical components used to create the desired appearance and beam pattern for the lighting emitting diode（LED） devices and *** this paper,design methodologies of the total internal reflective（TIR） LED secondary optics are investigated,which are deduced from the Snell’ s law[1]according to the conservation of energy,etendue conservation[2]and edge-ray principle[3].High efficiency and good uniformity are realized,every rays emitted from the LED are considered to create a high efficiency and uniform desired light pattern.

关键词： LED secondary optics Optical design Freeform optics Etendue conservation Edge ray principle

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

作者：萨伊( Say j.b.)

学校读者我要写书评

暂无评论

美国总统的科技顾问

世界经济与政治论坛 1990年第5期 22-25页

作者： j.b.威斯纳吕联合麻省理工学院

就在苏联的人造地球卫星升空之后,美国白宫立刻建立起了它有史以来最佳的科学顾问系统。总统比以往任何时候都更迫切需要及时的、富有成效的科学咨询,现在正是恢复这个已长期不存在的系统的时候。在1988年总统竞选期间,《华尔街日报》... 详细信息

就在苏联的人造地球卫星升空之后,美国白宫立刻建立起了它有史以来最佳的科学顾问系统。总统比以往任何时候都更迫切需要及时的、富有成效的科学咨询,现在正是恢复这个已长期不存在的系统的时候。在1988年总统竞选期间,《华尔街日报》在一篇头版专栏文章中写到: '在此次选举年里,科学是个大问题。无论是谁问鼎白宫,科学都将是在政治生活中的一件大事。

关键词：美国白宫专栏文章政治生活华尔街日报艾森豪威尔政府部门工作杜鲁门专业小组空间计划指挥控制

Irreversibility investigation of Casson fluid flow in an inclined channel subject to a Darcy-Forchheimer porous medium:a numerical study

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 95-108页

作者： A.ROjA b.j.GIREESHA b.NAGARAjA Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShimoga 577451KarnatakaIndia

The heat transfer and entropy generation characteristics of the magnetohydrodynamic Casson fluid flow through an inclined microchannel with convective boundary conditions are ***,the effects of the viscous forces,joule heating,heat source/sink,and radiation on the flow are taken into *** non-dimensional transformations are used to solve the governing ***,the reduced system is resolved by the fourth-fifth order Runge-Kutta-Fehlberg method along with the shooting *** effects of different physical parameters on the heat transfer and entropy generation are discussed in detail through *** the perspective of numerical results,it is recognized that the production of entropy can be improved with the joule heating,viscous dissipation,and convective heating *** is concluded that the production of entropy is the maximum with increases in the Casson parameter,the angle of inclination,and the Hartmann *** the Reynolds number and the radiation parameter cause the dual impact on entropy generation.

关键词： inclined channel Casson fluid magnetism radiation entropy generation bejan number

Optimization of heat transfer in the thermal Marangoni convective flow of a hybrid nanomaterial with sensitivity analysis

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1663-1674页

作者： j.MACKOLIL b.MAHANTHESH Centre for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Bengaluru 560029KarnatakaIndia

The heat transfer rate of the thermal Marangoni convective flow of a hybrid nanomaterial is optimized by using the response surface methodology(RSM).The thermal phenomenon is modeled in the presence of a variable inclined magnetic field,thermal radiation,and an exponential heat *** estimated values of the thermal conductivity and viscosity of the hybrid nanomaterial are utilized in the *** governing intricate nonlinear problem is treated numerically,and a parametric analysis is carried out by using graphical visualizations.A finite difference-based numerical scheme is utilized in conjunction with the 4-stage Lobatto IIIa formula to solve the nonlinear governing *** interactive effects of the pertinent parameters on the heat transfer rate are presented by plotting the response surfaces and the contours obtained from the *** mono and hybrid nanomaterial flow fields are *** hybrid nanomaterial possesses enhanced thermal fields for nanoparticle volume fractions less than 2%.The irregular heat source and the thermal radiation enhance the temperature *** high level of the thermal radiation and the low levels of the exponential heat source and the angle of inclination(of the magnetic field)lead to the optimized heat transfer rate(Nux=7.46275).

关键词： inclined magnetic field Marangoni boundary layer flow sensitivity analysis hybrid nanofluid exponential heat source response surface methodology(RSM)

在线全文

学校读者我要写书评

暂无评论

达摩波罗与僧伽罗佛教民族主义

世界社会科学 1993年第9期 11-15页

作者： j.b.迪萨纳雅卡 ,古柯

一、导言阿纳加里卡·达摩波罗是僧伽罗佛教民族主义历史上近年最有影响的人物。1933年结束了69岁的生命旅途,但是他所倡导的许多理想和理念至今仍不时受到推崇、赞誉或批判。达摩波罗创立的大菩提会去年

关键词：佛教伽罗释教达摩波罗僧伽罗人民族主义

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

肿瘤学

1988年

作者： (美)j.b.布洛克

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

学龄前儿童的特点

比较教育研究 1990年第1期 53-55页

作者： j.b.亨德里克杨春发

学龄前儿童一股指2至5岁的儿童。虽然不同年龄儿童之间和世界不同地区儿童之间在发展特点上存在明显的差异,但一些基本特征适用于整个学龄前时期和不同文化的儿童。这些特点之一是,学龄前儿童成长和发育特别快,因为在这短矩的时期内,... 详细信息

学龄前儿童一股指2至5岁的儿童。虽然不同年龄儿童之间和世界不同地区儿童之间在发展特点上存在明显的差异,但一些基本特征适用于整个学龄前时期和不同文化的儿童。这些特点之一是,学龄前儿童成长和发育特别快,因为在这短矩的时期内,他们学会语言,开始从受家庭群体保护的生活扩展到更加广阔的社会生活。在人的整个一生中,学龄前儿童成长的活力在婴儿期最大,

关键词：学龄前儿童发展特点基本特征家庭群体社会生活婴儿期文化语言成年人皮亚杰

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A journal of Chinese Universities) 2019年第2期34卷 229-252页

作者： j Dhivya b Sridevi Department of Mathematics Kumaraguru College of TechnologyCoimbatoreTamil NaduIndia Department of Mathematics PSG College of TechnologyCoimbatoreTamil NaduIndia

Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers is proposed. The proposed similarity measure provides reasonable results not only for the sets available in the literature but also gives very reasonable results, especially for fuzzy sets as well as for most intuitionistic fuzzy sets. To provide supportive evidence, the proposed similarity measure is tested on certain sets available in literature and is also applied to pattern recognition and medical diagnosis problems. It is observed that the proposed similarity measure provides a very intuitive quantification.

关键词： Fuzzy sets (FSs) Intuitionistic fuzzy sets (IFSs) Most intuitionistic fuzzy sets (MIFSs) Simi- larity measure (SM) Transformed triangular fuzzy numbers (TTFNs)