新型传感器测量断路器动特性的研究

通过对断路器触头运动特性的分析,提出采用硅压阻MEMS技术的加速度传感器来测量断路器触头运动特性的方法,并详细介绍了3031型加速度计的特点。同时采用滤波算法对测量数据的进行修正。使用MEMS型加速度传感器,测量准确、安装方便,建议在全国范围内推广使用。     

型传感器测量断路器动特性的研究

通过对断路器触头运动特性的分析,提出采用硅压阻MEMS技术的加速度传感器来测量断路器触头运动特性的方法,并详细介绍了3031型加速度计的特点。同时采用滤波算法对测量数据的进行修正。使用MEMS型加速度传感器,测量准确、安装方便,建议在全国范围内推广使用。     

智能光电探测器线性测量系统的研究

阐述了光电探头线性测量原理和方法,提出了基于双光源叠加法,利用积分球混光完成辐照度叠加,测量了超高亮LED随内部电流变化的光谱特性,测量结果证明:辐照光源使用超高亮LED的可行性。设计中以计算机编程自动控制实现智能化和自动化完成光电探测器的线性测量为宗旨,对系统的各部分结构、原理、特点及创新性进行分析。讨论了测量系统的不确定度来源与处理方法。对硅光电探头进行多次线性测量,重复精度优于±0.5%,测量结果证明:该系统设计自动化程度和精度较高,可以作为光电探测器线性测量装置。     

光电经纬仪站址与测角测距误差校准

光电经纬仪校准是实现目标精确测量的关键,在设备经过一段时间的使用或移站后均需进行校准.针对近期一次光电经纬仪校准工作中,以设备旋转中心测量值作为站址坐标真值进行其他参数校准时产生了无规律且较大测角偏差的问题,提出一种基于地面控制的光电经纬仪站址与测角测距误差校准方法.相比其他类似校准方法,该方法将站址坐标、测角误差和测距误差均作为未知量进行校准模型构建,通过平差计算,得到一组最优的校准数据作为光电经纬仪测量的基准.经试验验证,该方法有效提高了光电经纬仪测量精度和可靠性,同时校准结果可直接用于光电经纬仪数据处理软件,保证光电经纬仪测量处理的规范化.     

四元数法在动基座光电测量坐标变换中的应用

寻求一种高效的坐标变换算法一直是动基座光电测量系统中亟待解决的问题,由此研究了四元数法在动基座光电测量系统坐标变换问题中的应用;利用四元数作为旋转算子的特性,提出了一种改进的坐标变换方法,并利用这种方法推导了视轴从光电平台坐标系到载机坐标系的变换矩阵和在载机坐标系下的方位角、俯仰角计算公式;最后将该方法运用在某机载光电测量系统上,通过采用四元数法和常规方法分别进行地面仿真的数据分析结果,验证了该方法的准确性和优越性。     

一种高精度定位设备光电系统标校方法

针对外场光电系统测量精度的标校存在的不足等问题,提出了一种基于GPS的光电系统测量精度的标校方法。在标校系统组成及标校原理分析基础之上,进行了理论指向和距离的解算推演,并分析了GPS定位误差对标校系统精度的影响。该方法能有效地克服场地选择困难和角度范围小等不足,满足光电系统测量精度标校的要求。     

车载光电经纬仪不落地测量的实时误差修正方法

车载光电经纬仪是广泛应用于军事和航天领域的高机动性光学精密测量仪器,为保证精度,在使用过程中往往需要与地基环连接,将经纬仪固定到指定的地基上;为充分发挥车载光电经纬仪机动灵活的特点,摆脱地域的限制,文章对车载光电经纬仪不落地测量的误差修正方法进行了系统的研究;借助一种基于双光栅干涉产生莫尔条纹测量扭转角的高精度光学测角方法,通过对某型号车载光电经纬仪在不接地基环情况下的测量实验与数据分析,建立起一套完善的实时误差修正方法,并通过恒星标定验证了该方法的正确性与有效性,并对修正前后的测量精度进行比较;实验结果表明,该方法将某型号车载光电经纬仪在不落地情况下的测量精度从原来的70 arc sec左右提高到10 arc sec以内,在保证精度的前提下,实现了车载光电经纬仪的不落地测量.     

基于光电标签的火箭橇全程测速技术研究

火箭橇试验在兵器研制和性能测试上起着至关重要的作用,现有火箭橇测速方法均存在一些不足之处,针对火箭橇试验中全程速度测量难题,提出了一种基于光电标签的火箭橇全程速度测量方法;建立了光电标签的探测模型,对光电标签的原向反射特性进行研究,分析并仿真了传感器在动态测量中的信号变化过程,基于信号的频率特性对光电探测器件与信号处理电路进行选型,设计并搭建出硬件测量电路,对系统进行了测试与验证;实验结果表明：传感器对光电标签的探测距离可达40cm,系统速度测量范围满足了火箭橇试验在兵器靶场上的应用,与传统方法相比,光电标签法成本更低、易实现,在火箭橇全程速度测量中有更广泛的应用场景。     

四象限光电探测器象限间一致性测量方法

将四象限光电探测器应用于目标方位测量时,探测器四个象限的一致性至关重要.用日光灯灯光作光源测量四象限光电探测器象限间响应度一致性,此方法简单有效,容易实现,且能达到较高的精度.用此方法测量了一个GT111四象限光电探测器,其象限间响应度一致性＞82%,测得的结果显示GT111四象限光电探测器具有较好的象限间响应度一致性.     

计算机辅助激光成像雾滴尺寸测量系统

文章研究了计算机辅助激光成像测量雾滴尺寸的方法,分析了系统的学系统、光电二极管阵列及其光电检测系统和数据采集系统等.     

Discovering relationship types between users using profiles and shared photos in a social network

In this paper, we propose a new approach to discover the relationship types between a user and her contacts in a social network. This is of key importance for many applications in the domain of photo sharing, privacy protection, information enriching, etc. Our approach is based, on one hand, on information extracted from users’ profiles and their shared photos, and, on the other hand, on a set of predefined rules validated by the main user before being mined and derived according to her preferences and social network content. The contribution of our method is twofold: 1) it is user-based enabling the user to set her preferences and give her feedbacks on the derived rules and results, and 2) it is multi-criteria that exploits and combines several attributes and features from user profiles and shared photos respectively. It also allows the user to define new relationship types. We conducted a set of experiments to validate our approach. The obtained results show the accuracy of our approach in different scenarios.     

Secure identification documents via pattern recognition andpublic-key cryptography

We present an approach to authenticating photo-ID documents that relies on pattern recognition and public-key cryptography and has security advantages over physical mechanisms that currently safeguard cards, such as optical laminates and holograms. The pattern-recognition component of this approach is based on a photo signature that is a concise representation of the photo image on the document. This photo signature is stored in a database for remote authentication or in encrypted form on the card for stand-alone authentication. Verification of the ID document entails scanning both the photo image and a machine-readable form of the text information, determining the photo signature, and comparing this information against the reference. In this paper, we describe the method and present results of testing a large database of images for photo-signature match in the presence of noise     

Automatic rule generation using crowdsourcing for better relationship type discovery

With the increasing popularity of information sharing and the growing number of social network users, relationship management is one of the key challenges which arise in the context of social networks. One particular relationship management task aims at identifying relationship types that are relevant between social network users and their contacts. Manually identifying relationship types is one possible solution, however it is a time-consuming and tedious task that requires constant maintenance. In this paper, we present a rule-based approach that sets the focus on published photos as a valuable source to identify relationship types. Our approach automatically generates relevant relationship discovery rules based on a crowdsourcing methodology that constructs useful photo datasets. Knowledge is first retrieved from these datasets and then used to create relationship discovery rules. The obtained set of rules is extended using a number of predefined common sense rules and then personalized using a rule mining algorithm. Experimental results demonstrate the correctness and the efficiency of the generated sets of rules to identify relationship types.     

Molecular detection based on the electrical conductance of gold nanoparticle arrays

We report a molecular sensing method based on changes in the electrical conductance of lithographically defined gold nanoparticle (NP) arrays immersed in an analyte solution. As the closely spaced NPs are enlarged due to the analyte-mediated deposition of gold ions onto their surfaces, the conductance increases steeply near the critical time (t_c) at which conducting pathways begin to form in the NP arrays. t_c decreases with increasing analyte concentration in the solution. The temperature dependence of the conductance of the modified NP arrays confirms the good electrical contacts established between the newly formed nanoclusters on the NP surfaces. Our results demonstrate that the electrical conductance through metal NP arrays can be employed as a sensitive and reliable analytical signal for NP-based sensors, which do not require any post-processing for the formation of electrical contacts between the NPs.     

Electrical characterization of megabit DRAMs. 1. External testing

An approach to the electrical characterization of dynamic RAMs in which chip design and DRAM process technology are verified and optimized concurrently is reported. Both parametric and functional tests were performed. The authors describe an information and scheduling system for analysis and testing that handles the required electrical measuring data from the testers. It is shown how data analysis supports the interpretations by data correlations on a real statistical basis. The short learning cycle required by this approach was obtained by ensuring the smooth cooperation of all those involved in the overall analysis     

本体推理在智能照片管理系统中的应用

现有的照片管理系统缺乏自动语义推理和扩展功能。为此,提出一种基于本体的智能照片管理系统。该系统以FamilyAlbum本体模型为知识框架,对照片进行多源信息的语义标注,并利用SWRL规则对系统中现有的语义标注进行自动推理,从而扩展出新的语义信息,为照片的智能管理提供有效支持。通过OntoAlbum原型系统的实现,验证了该方法的有效性。     

SmartTouch: electric skin to touch the untouchable

Augmented haptics lets users touch surface information of any modality. SmartTouch uses optical sensors to gather information and electrical stimulation to translate it into tactile display. Augmented reality is an engineer's approach to this dream. In AR, sensors capture artificial information from the world, and existing sensing channels display it. Hence, we virtually acquire the sensor's physical ability as our own. Augmented haptics, the result of applying AR to haptics, would allow a person to touch the untouchable. Our system, SmartTouch, uses a tactile display and a sensor. When the sensor contacts an object, an electrical stimulation translates the acquired information into a tactile sensation, such as a vibration or pressure, through the tactile display. Thus, an individual not only makes physical contact with an object, but also touches the surface information of any modality, even those that are typically untouchable.     

Measurement system for low force and small displacement contacts

To support the continued miniaturization of electrical contacts in multichip systems, three-dimensional (3-D) systems, wafer probe cards, and MEMS relays, there is a need for combined measurements of electrical and mechanical phenomena during contact formation. We have carried out a study of electrical contacts in the nN-mN force range for future generation probe cards and novel electronic packaging. One critical phenomenon in the contact formation process is nm-scale deformation of the material layers. To directly study this contact displacement, we have designed a measurement system comprised of a piezoresistive cantilever and an optical interferometer. Together, this system simultaneously measures contact resistance (mOhm to kOhm), force (nN to mN), and displacement (nm-/spl mu/m). These measurements allow the first direct observation of contact mechanical behavior in this important application range. These measurements show that asperities at the contact surface dominate the behavior of the contacts, causing deviations from the Hertzian model of elastic contacts. This paper describes the design and construction of this apparatus, and the operation in a contact mechanics experiment.     

复杂背景中的模式识别

研究在复杂背景中检测出人脸区域的方法,利用肤色模型对照片的可能人脸区域提取出来,再对肤色区域进行灰度化处理并修正,最后通过神经网络的方法对可能区域进行再判别.     

剩余电压检测方法的研究

根据家用电气产品安全标准的要求,分析了剩余电压的放电原理,提出了一种高精度的剩余电压检测方法,设计了一台剩余电压检测装置,用于家电产品剩余电压的检测。介绍了测量仪器的实现方案,最后在实际应用中证明了该仪器有效可行。