基于CMOS APS高精度太阳敏感器

通过对CMOS APS的简要介绍以及它与CCD的性能比较,揭示出CMOS APS在太阳敏感器的研究发展方面所具有的优越性.在提出CMOS APS太阳敏感器一般方案的同时,对它进行了更进一步的探讨.并在探讨太阳敏感器视场和精度相互制约这一问题的过程中,结合CMOS APS各方面的优点,阐明了这一问题虽然在CCD太阳敏感器中难以解决,但在CMOS APS太阳敏感器中却可以得到有效解决.     

附录F 采用有源像元敏感器（APS）的数字式太阳敏感器

荷兰全国应用科学研究中心TPD研究所(TNO TPD)正率领一个工业小组与索登公司(SODERN，法国)和Fillfactory公司(比利时)一起，开发一种采用有源像元敏感器(APS)的数字式太阳跟踪敏感器。这项工作起源于欧洲空间局一法国环境科学技术发展协会(ESA-ASTE)技术大纲，拟于2002年2月鉴定样机。     

基于PSD的高精度太阳敏感器电子学系统设计

针对目前国内太阳观测成像仪器稳像系统的需要,提出了一种基于位置敏感探测器(PSD)的高精度太阳敏感器电子学系统的设计,有针对性地提出了提高灵敏度的设计方案和降低系统噪声的具体措施.该系统噪声水平低于4 nA,在工作范围中心区域具备了0.3"的高分辨能力,可以配合偏摆镜结构组成稳像系统,服务于夸父和SPORT计划等具有高分辨率成像需求的太阳成像仪器.     

基于MOEMS的微型数字太阳敏感器

结合CMOS APS图像传感器与MEMS工艺的优势,研制了一种适用于微纳卫星的两轴数字太阳敏感器,在保证测量精度的同时,减小了系统的体积与功耗.其光学系统由CMOS APS图像传感器和MEMS工艺制作的孔阵列结构光学引入器组成,提高了敏感器的分辨率,扩大了有效视场的范围.利用太阳模拟器对数字太阳敏感器进行了测试标定,结果表明,在120°圆锥全视场范围以内,1σ精度优于0.035°.     

基于微机电系统的太阳敏感器

卫星姿态确定分系统广泛采用太阳敏感器来测量卫星坐标系中的太阳矢量。本文介绍一种基于微机电系统(MEMS)的实验型太阳敏感器。这台太阳敏感器样机包含一块带有数百个小孔的硅片掩模。掩模安放在一只电荷耦合器件(CCD)焦平面阵列顶上，距焦平面750μm。当太阳照射此装置时，在焦平面上形成孔径图像。对这个图像进行分析，就可以算出太阳角。试验数据表明，这种太阳敏感器可以达到的精度约为二三角分，或者更好一点。计划利用一个有源像元敏感器(APS)焦平面阵列器件，把这种太阳敏感器的体积做得像3个美国1角银币相互重叠起来那么大，其质量轻于30g，功耗低于20mW。这种太阳敏感器将成为微型与超小型卫星以及小型行星漫游车上使用的理想部件。     

太阳敏感器电模拟器设计

针对小卫星半实物仿真系统的技术需求,提出了一种太阳敏感器电模拟器设计实现方法;模拟器以FPGA作为控制核心,采用压控电流源实现了0-1式太阳敏感器、模拟式太阳敏感器的输出电流模拟;通过专用电流源芯片REF200实现了数字式太阳敏感器输出电流模拟;模拟器由计算机通过RS-485接口控制,既能模拟太阳敏感器正常工作时的电信号输出,也能模拟太阳敏感器出现故障时的电信号输出;该太阳敏感器电模拟器已应用于小卫星的半实物仿真,其电流精度可达±1μA。     

大视场数字式太阳敏感器设计

提出了一种新型的大视场数字式太阳敏感器设计方法,其光学系统由全景环形光学镜头和滤光膜组成.该敏感器具有视场大、结构简单及功耗低的特点.从工作原理出发,建立了该敏感器模型,并利用搭建的实验平台,对敏感器进行精度标定.设计中,采用非线性最小均方最优解来确定模型中的参数.对测量误差进行分析,消除系统误差后,敏感器的测量精度由...     

CCD噪声模型在几何最优线性姿态估计中的应用

星敏感器噪声主要来源于CCD图像传感器和控制与数据处理电路,这些噪声对姿态估计精度的影响不容忽视.在研究了CCD图像传感器中光子散粒噪声、暗电流噪声、电荷转移噪声及读出噪声四种主要噪声的基础上,分析了它们对亚像元质心法提取精度的影响.根据亚像元质心法提取结果,采用几何解析的最优线性姿态估计(OLAE)方法解算卫星姿态.仿真结果表明:考虑星敏感器噪声模型比单纯引入高斯白噪声具有更高的姿态估计精度.     

用于超小型地球观测卫星的基本APS的微型太阳敏感器

本文介绍那不勒斯(Naples)大学对于用在微型与超小型卫星姿态确定系统中的一种基于APS的低成本微型太阳敏感器的研究工作与样机开发情况，阐述这种敏感器的总体结构以及样机和实验室测试设备的开发工作。开发该敏感器的数字仿真器也是本项目的重要内容。这种仿真器用来预测敏感器性能，并模拟样机的实验室测试。初步结果显示，敏感器最终精度优于1’。     

面向微小卫星的全视场数字太阳敏感器设计

本文提出一种新型的全视场数字太阳敏感器设计方法,其光学系统由全景鱼眼镜头和滤光膜组成。采用低功耗设计,在满足精度的要求下,使其能够适应微小卫星对于数字太阳敏感器功耗的限制。从工作原理出发,建立起该敏感器模型并通过软硬件实现,利用太阳模拟器对数字太阳敏感器进行标定及误差分析。实验表明,基于全景鱼眼镜头的数字太阳敏感器的视场为180°×360°,在160°×360°视场的测量3δ精度优于0.18°,整机功耗150 mW,能够满足微小卫星姿态确定系统对于数字太阳敏感器的需求。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.