陶瓷湿敏电阻器静态校准曲线的线性拟合

陶瓷湿敏电阻器是湿度传感的重要元件,但因其阻-湿特性往往呈非线性而使用不便。本文利用最小二乘法对典型的铬镁钛系陶瓷湿敏电阻的阻-湿特性进行了线性拟合。结果表明,这种线性拟合方法简单可行,可用于非线性湿敏等敏感电阻器件的线性化处理。     

Modeling of multi-inclusion composites with interfacial imperfections:Micromechanical and numerical simulations

A micromechanical approach based on a two-layer built-in model and a numerical simulation based on boundary element method are proposed to predict the effective properties of the multi-inclusion composite with imperfect interfaces.The spring model is introduced to simulate the interface imperfection.These two methods are compared with each other,and good agreement is achieved.The effects of interface spring stiffness,volume ratio and stiffness of inclusions on the micro-and macro-mechanical behaviors of fib...     

弹道方程边值问题中的直射弹道公式

本文探求了属于微分方程边值问题的直射弹道公式,以形简、意明、精确度高、研究方法的多样性和事物规律的不同表现形式为特征。在直射弹道的定义和数学描述之后,先从它的微分方程出发推导出了公式;再从方程的数字解出发探寻并确立了其规律性。     

论城市品格的塑造——以镇江为例

城市品格是城市无形层面里最本质的部分。城市品格的塑造需要渗入人文精神和城市特色,这样才能使人们生活得更美好。对镇江而言,要塑造城市品格,就需要立足镇江的历史与现实,结合镇江民众的思考,从功利与超功利的角度进行具体的探索。     

用Decklink Duo采集卡实现双通道SDI输出

在靶场光电测量任务中,为满足远距离实时监测任务进展的需求,常要将数字相机采集的图像信号转换为SDI视频信号,并将相应信息叠加后显示输出。针对这一问题,以Microsoft Visual Stdio 2010为软件开发平台,结合OpenCV2.4.11,利用Decklink Duo采集卡将Camera Link Full图像视频信号转换为双通道SDI信号输出,并分别对这些信号进行了文字信息叠加显示处理以及模拟红外伪彩色处理。实验达到了预期的显示效果,证明该方法有效,可以满足实际任务的要求。     

轴承压印字符自动识别算法的研究

为了方便轴承的生产和管理,针对轴承上字符的特点,提出了一种自动识别轴承压印字符的方法。首先借助环形光源,利用"反光差"产生并采集字符图像;然后利用随机Hough变换定位轴承圆心,并确定目标字符的位置;通过对单个字符进行仿射变换矫正字符区域;最后提取轮廓层次特征,并使用支持向量机识别。实验表明,该方法能够实现轴承字符的自动识别,并能满足实时性和识别率的要求。     

Understanding individual defects in CdTe thin-film solar cells via STEM: From atomic structure to electrical activity

Here we review a systematic study of the structure-property correlations of a series of defects in CdTe solar cells. A variety of experimental methods, including aberration-corrected scanning transmission electron microscopy, electron energy loss spectroscopy, energy dispersive X-ray spectroscopy, and electron-beam-induced current have been combined with density-functional theory. The research traces the connections between the structures and electrical activities of individual defects including intra-grain partial dislocations, grain boundaries and the CdTe/CdS interface. The interpretations of the physical origin underlying the structure-property correlation provide insights that should further the development of future CdTe solar cells.     

Preparation and characterization of new window material CdS thin films at low substrate temperature (<300 K) with vacuum deposition

Low-temperature vacuum deposition instead of the commonly used vacuum deposition at high substrate temperatures has been applied to prepare new window material CdS thin films. The structural, optical and electrical properties of vacuum-evaporated CdS thin films were investigated as a function of substrate temperature (100–300 K) and the post-deposition annealing temperature (at 473, 573 and 673 K). It was determined that films deposited at all substrate temperatures were polycrystalline in nature with hexagonal structure and a strong (0 0 2) texture. The AFM and SEM studies showed that the microstructures of the as-deposited films agreed with the expectations from structure zone model. X-ray diffraction studies showed that the crystallinity of the CdS films was improved on annealing. Optical spectroscopy results of the films indicated that the optical band gap value increased from 2.40 to 2.42 eV with decreased substrate temperature. Increasing the annealing temperature sharpened the band edge. The dark resistivity increased from 4.5×10³ to 7.3×10³ Ω cm and the carrier concentration decreased from 4.7×10¹⁷ to 3.5×10¹⁵ cm⁻³ as the substrate temperature decreased from 300 to 100 K.     

A MAC Protocol for Multimedia Traffic in Slotted CDMA Wireless Communication Systems

In this paper, a media access control (MAC) protocol is proposed for multimedia traffic in slotted CDMA wireless communication systems. The channel resource is partitioned into four compartments: video, voice and data compartments, and common resource pool (CRP) which can be used by either voice or data. Video is only permitted to use its pre-allocated channels. Besides assigning voice to its own compartment, a threshold type decision policy is introduced to regulate voice call admission control in CRP. Data can use not only data and CRP compartments, but also the idle capacity of both video and voice. The proposed protocol provides a simple and flexible resource allocation decision for the multimedia traffic such that the bandwidth can be utilized efficiently while satisfying the quality of service (QoS) requirement for each traffic category. Two mathematical analysis methods are applied to evaluate the system performance. The first, Traditional Markov Analysis (TMA) is used to calculate the video and the voice blocking probabilities, and the second, Transient Fluid Analysis (TFA) is adopted to evaluate the average data delay and the channel utilization. Computer simulations verify the accuracy of mathematical models.Miao Ma received the B.Eng. and M.Eng. degrees in Electrical Engineering from Harbin Institute of Technology, China in 1992 and 1996, respectively, and the Ph.D degree in Electrical and Electronic Engineering from Nanyang Technological University, Singapore in 2003. She is a research scientist in the Institute for Infocomm Research in Singapore. Her research interests include network security, media access control, wireless communications and computer networking.Erry Gunawan received the B.Sc. degree in electrical and electronic engineering from the University of Leeds, U.K., in 1983 and the M.B.A. and the Ph.D. degrees, both from Bradford University, in 1984 and 1988, respectively. From 1984 to 1988, he was a Satellite Communication System Engineer at Communication Systems Research Ltd., Ilkley, U.K. In 1988, he moved to Space Communication (SAT-TEL) Ltd, Northampton, U.K. He joined the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, in 1989, and currently, he is an Associate Professor in the same school. His research interests include the fields of digital communications, mobile and satellite communications, error coding, and spread spectrum. He has published over 60 international research papers and has been a consultant to a local company on the study of DECT system and BLUETOOTH.     

人工智能技术研发实践与产品规划战略思考

人工智能技术在各个行业的应用均体现出爆发趋势,但是AI技术的性能局限同时约束着相关产品的应用场景。在感知方面,识别算法的准确率无法达到100%,召回率更低;在认知方面,知识难以100%覆盖业务场景,因此如何开展商业化应用就需要精心规划。本文首先介绍几项AI产品研发应用,并总结相关的经验和问题。在此基础上,按照面向任务关键应用(MCA)和非任务关键应用(NMCA)2个维度,针对4个应用类型(决策支持与增强、智能代理、决策自动化、智慧产品),围绕3类商业价值和2类应用假设,分析AI类应用产品的战略规划决策要素,为AI应用领域决策者提供帮助。