示准化学科行为互换性定律的创建

本文讨论了互换性定律的族系,研究了非训练行为不准确现象,讨论了行为互换性的需求,推论了行为互换性定律的存在,建立了行为互换性的概念,创建了行为互换性定律的命题及其数学模型,详述了定律的内涵,分析了行为互换性与其他互换性的关系,讨论了行为互换性定律的对象范围、互换类型、自身特点和作用意义,对行为互换性定律进行了验证分析,讨论了行为互换性定律的应用,并给出了应用例子。     

从《互联网时代》看纪录片与社会的关系

《互联网时代》是以全球背景下的视野,聚焦了历史、聚焦了文化、聚焦了社会功能,通过十集的影像表达,缔造了一个时代所呈现的互联网巨大变革,满足了受众,创造了经济效益,开创了中国纪录片史上的又一个里程碑,同时创造了较高的社会现实意义。完成了近乎完美的中国映像,为中国纪录片占有国际地位奠定了社会基础。     

标准化性质的研究

本文论述了研究标准化性质的意义,阐述了4个性质的内涵,分别研究了其理论关系和特点,提出了4个性质的证明方法,并作了相应证明,论述了4个性质的应用关系,给出了部分代表性的应用领域。     

径向冲孔模设计

对盒体零件的冲孔工艺方案进行了分析,介绍了各种冲孔工艺方案的优缺点,从而确定了利用凸轮机构,实现了该零件的径向冲孔。介绍了该模具结构及工作过程,给出了零件的工艺计算方法,提出了模具的设计方法,为解决同类零件的冲孔提供了参考。     

社团活动对大学生心理成长的作用

健康有益的社团活动不仅丰富了校园文化，培养了学生的兴趣爱好，扩大了学生的求知领域，使大学生活丰富多彩，而且对大学生的心理成长具有积极的作用。即社团活动使大学生获得了归属感，丰富了情感体验，提高了交往能力，增强了合作意识，提升了自信心，促进了大学生社会化的进程。     

标准化学科几何互换性定律的创建

本文讨论了规律和定律的关系和特点,讨论了几何互换性的本质关系,推论了互换性定律的存在,创建了动配合互换性定律、定位配合互换性定律、紧配合互换性定律,建立了定律的命题、数学模型和关系模型,详述了每个定律的内涵,创建了支持互换性工程应用的几何互换性空间,讨论了互换性定律的应用,创建了广泛适用的互换性空间。     

基于3D Gerstner水波的实时模拟研究

简述了模拟水波的原理,使用面向对象方法对水波3D实时模拟系统进行了结构设计,给出了设计模式的结构图,提出了一个可复用的系统框架.详细介绍了使用HLSL对Gerstner水波进行编程的方法,实现了水波实时渲染的模拟并给出了关键的程序代码.最后分析了使用Gerstner波进行水波模拟存在的不足并提出了改进建议.     

浅谈标准养蟹优化质量调整结构促进增收

通过农业标准化示范区建设项目的实施,促进了农产品质量安全水平的提高,延伸了产业链条,加快了全市农业产业化、现代化的进程,提高了农民的标准化意识,改善了生态环境,促进了可持续发展,为促进农业增效、农民增收起到了巨大作用。     

矢网在测量传输线特性阻抗中的应用

本文介绍了如何使用矢量网络分析仪测量非50n的同轴传输线的特性阻抗,从理论入手,提出了测量方法,然后建立了模型并进行了仿真,最后用矢量网络分析仪进行了测量,得出了卖际测量曲线,分析了测量曲线,得出了正确的测量方法和测量结果。     

永磁体磁偏角测量方法的研究

本文提出了一种基于亥姆霍兹线圈的永磁体磁偏角测量方法,按照测量原理构建了三维数学模型并研制了测量装置,实现了磁偏角的自动测量,提出了相应的校准方法,最后通过实验验证了该方法的有效性,并进一步提出了简化的二维测量方法.     

Effect of friction stir welding process parameters on Mg-AZ31B/Al-AA6061 joints

In the present study, dissimilar alloys such as Mg-AZ31B and Al-AA6061 were joined by friction stir welding using different rotational (560, 710, 860 and 1010?rpm) and transverse speeds (16 and 25?mm/min). Metallographic studies (by optical, scanning electron microscope, SEM, and energy dispersive spectrometer, EDS) revealed that the speed parameters mainly influenced the microstructure growth mechanism, which further affects the mechanical properties and corrosion behavior. The combined dynamic action of rotational to transverse speed recrystallized and plasticized the material and produced an alternative lamellar shear band of Al and Mg in the stir zone (SZ). Peak temperature and high rotational speed formed an oxide on the top region and also caused liquation and intermetallic (IMCs) formation. Tensile strength and hardness increased as per the Hall–Petch (fine grains) effect. Higher impact energy was found at moderate rotational and low transverse speeds due to the presence of more soft Al patches. Tensile fractographs showed a river-like pattern, which indicated the brittle nature of the joints. High rotational and high transverse speed illustrated higher tensile strength, while better corrosion resistance was observed in high rotational and low transverse speed.     

Fault diagnosis and refrigerant leak detection in vapour compression refrigeration systems

The environmental impact of refrigeration systems can be reduced by operation at higher efficiency and reduction of refrigerant leakage. Refrigerant loss contributes both directly and indirectly to global warming through inefficient system operation, increased power consumption and greenhouse gas emissions and higher maintenance costs. Existing sensor-based leak detection methods are limited by the inability to detect gradual leakage and the need for careful sensor location. There is a requirement for a real-time performance monitoring approach to leak detection and fault diagnosis which overcomes these disadvantages.This paper reports on the development of a fault diagnosis and refrigerant leak detection system based on artificial intelligence and real-time performance monitoring. The system has been used successfully to distinguish between faulty and fault free operation, steady-state and transient operation, leakage and over charge conditions. Work currently underway is aimed at testing additional fault conditions and establishing further rules to distinguish between these patterns.     

中国制冷空调行业制冷剂替代策略的思考

中国制冷空调行业淘汰HCFCs面临国际上的巨大压力和挑战。为此,从直接排放和间接排放2个方面对制冷剂应用对环境影响以及从制冷剂管理方面进行分析与阐述,提出制冷空调行业应负责任地使用制冷剂:提高制冷空调设备效率,降低制冷剂间接排放,减少制冷剂充注量,加强控制制冷剂泄漏,提高制冷剂回收、再生利用率来减少制冷剂的直接排放;应进行可燃制冷剂应用的基础研究和制定产品及应用安全标准,寻找对环境影响最小、经济可行、替代成本市场可接受、安全的替代制冷剂。同时建议行业协会配合国家有关部门制定适合中国国情的HFCs制冷剂的减排基准线和减排时间表。     

Innovation, change, and order: Reflections on science and technology in India, China, and the United States

A comparative analysis of science and technology policies in China, India, and the United States shows striking similarities and sharp contrasts. These differences reveal much about the current problems and likely prospects in each country. This review distills the contributions of 15 distinguished leaders in science and technology who assess national goals and international ambitions. The review covers five themes: education, defense and space, R&D performers, science and technology in the economy, and governmental policies and funding. Other issues include: economic freedom, global competitiveness, energy and the environment, and population and demographic trends. Brief historical highlights provide context for understanding past trends in the present socioeconomic setting.     

Capabilities evaluation of WSEM,milling and hobbing for meso-gear manufacturing

This paper describes manufacturing capabilities evaluation of wire spark erosion machining (WSEM), milling and hobbing to manufacture meso straight bevel gear (MSBG) and meso helical gear (MHG) made of SS 304 using microgeometry, macrogeometry, flank surface topology, surface finish, microstructure, microhardness, manufacturing time and cost, and gear material loss. Experiments were conducted using the parameters of WSEM, milling and hobbing processes optimized through trial experiments. This study reveals that WSEM manufactured MSBG and MHG possess better microgeometry (DIN 5-7), macrogeometry (29, 33, and 46?µm deviation in span, tooth thickness and outside diameter for MHG), topology, higher microhardness, superior microstructure, lower manufacturing time (25 and 20?min, respectively) and cost ($ 4 for both), smaller loss of gear material but poor surface finish (1.07 and 6.60?µm as average and maximum surface roughness for MHG and 1.04 and 6.16?µm for MSBG) than milled MSBG and hobbed MHG. Microstructure study showed presence of burrs and marks of the cutting tool on the flanks of the best quality hobbed MHG and milled MSBG. It proves that WSEM is a superior, economical, material efficient, and environment friendly process to manufacture meso-sized cylindrical and conical gears of higher accuracy and better quality with excellent repeatability.     

科学 技术 工程及科学家 工程师 企业家

论述了科学、技术、工程的性质与相互关系以及科学家、工程师、企业家的任务；为科学技术创新，发展经济，振兴国家，指出了应采取的对策。     

Dispersion and surface functionalization of oxide nanoparticles for transparent photocatalytic and UV-protecting coatings and sunscreens

Abstract

This review describes recent efforts on the synthesis, dispersion and surface functionalization of the three dominating oxide nanoparticles used for photocatalytic, UV-blocking and sunscreen applications: titania, zinc oxide, and ceria. The gas phase and liquid phase synthesis is described briefly and examples are given of how weakly aggregated photocatalytic or UV-absorbing oxide nanoparticles with different composition, morphology and size can be generated. The principles of deagglomeration are reviewed and the specific challenges for nanoparticles highlighted. The stabilization of oxide nanoparticles in both aqueous and non-aqueous media requires a good understanding of the magnitude of the interparticle forces and the surface chemistry of the materials. Quantitative estimates of the Hamaker constants in various media and measurements of the isoelectric points for the different oxide nanoparticles are presented together with an overview of different additives used to prepare stable dispersions. The structural and chemical requirements and the various routes to produce transparent photocatalytic and nanoparticle-based UV-protecting coatings, and UV-blocking sunscreens are described and discussed.     

GLONASS时间频率传递研究

分析了基于GNSS的时间频率传递方法的发展趋势和GLONASS发展现状及趋势。对GLONASS时间频率传递进行了研究,就其原理实现、误差补偿及数据处理进行了阐述,实现了GLONASS时间频率传递的基本方法,实施了GLONASS和GPS时间频率传递实验。将两种时间频率传递结果进行了对比,对GLONASS时间频率传递自身性能进行了分析,结果显示:GLONASS时间频率传递已达到了可与GPS时间频率传递相比较的水平。     

A review of sustainability metrics for the construction and operation of airport and roadway infrastructure

Sustainability has become increasingly important, however, relatively little attention has focused on metrics for the construction and operation of airport and roadway infrastructure. Most attention has focused on buildings, with high profile BREEAM and LEED projects taking center stage. Sustainability is also important in airport and roadway infrastructure projects, which have significant public impact but have a much lower profile than vertical construction when it comes to sustainability. Sustainable infrastructure is important in China and India where new infrastructure is under construction to meet growing and developing economies, and in the US, where infrastructure is in substandard condition and requires reconstruction. The purpose of this paper is to provide an overview and discussion of sustainability rating systems for airport and roadway infrastructure, including both construction and operation. Specific projects that highlight both proven and innovative sustainable practices are included to illustrate the application of these concepts. Finally, the relationship between sustainable transportation infrastructure and resilient transportation infrastructure is addressed since resiliency is of growing interest and there is overlap between these concepts.     

Studies on Properties and Structure of Electroless Plating Tin Coating

The composition and structure of electroless tin coating were analyzed by SEM and X-ray diffraction. In the meantime, porosity, solderability and extensibility were determined by physical and chemical methods. The results showed that the porosity of the tin coating increases with the rise of bath temperature and decreases as the plating time rises. Solderability is improved with the rise of thickness of tin coating, and decreases when the tin deposit is heated at 180 ～ 200 ℃. The crystalline grain size becomes bigger and bigger with increasing plating time or bath temperature or coating thickness. X-ray diffraction indicates that only Cu and β-Sn phases show up in the diffraction patterns. Tin coating has a strong joint force with copper substrate and excellent function of electrochemical protection as anode coating.