基于海洋能的无人水下航行器能源发电装置设计

针对无人水下航行器在水下长时连续工作对能源的需求,提出了一种由两级转换系统构成的海洋动能发电装置方案,该装置可直接将海洋动能传递给发电机,去掉了中间的能量传递环节,可有效减小结构体积、提高系统的转换效率.基于永磁发电机基本原理和刚体绕定轴转动定律,建立了飞轮动能与电机输出电压的关系模型,结合项目组研制的海洋动能发电装置...     

模型预测控制在波浪能上应用的现状与挑战北大核心CSCD

为了提高波浪能源的利用效率,许多机构和学者在波浪能转换装置的模型预测控制方面进行了大量的研究。波浪能转换装置一般要求在保持安全运行的同时实现最大功率能量捕获,其控制方法本质上是一个约束优化问题,应用模型预测控制方法能够很好地满足这一要求。首先对模型预测控制理论进行介绍,其次对国内外关于模型预测控制在波浪能转换装置上应用的研究现状进行阐述,最后指出在波浪能转换装置上应用模型预测控制方法所面临的挑战及研究方向。     

激光式自动化检测钢轨波磨装置研究

针对目前机械式轨道波磨测量普遍精度不高,使用条件限制较多等缺点,研发了激光式自动化检测钢轨波磨装置。该装置主要采用非接触式激光传感器进行检测,采用步进电机带动传感器扫描钢轨表面,数据传输采用单片机结合WiFi上传给上位机,使用C#编写的上位机程序对数据进行采集分析处理。经过多个现场测试,设备能够稳定、准确地采集钢轨波磨数据,并且具有采集速度快,设备移动方便,钢轨波磨的检测效率高等优点。     

谐振频率转换机制振动能采集器研究进展

环境振动能采集器可为低功耗系统提供绿色环保、可再生能源,具有寿命长久、能量密度高、微型、易集成等优势.能量采集环境具有随机振动频率低、频域广、振源幅值小且多方向性等特点,频率转换机制可有效解决采集器与环境振动频率不匹配问题,提高其能量转换效率.发电装置中的拾振结构频变方式主要分为接触式和非接触式,具体操作方法包括直接或间接碰撞拾振体、驱使振动体形变、磁力耦合调频等.综合比较了各类频率转换机制的优缺点及其实用性,指出了低宽频、高效能、智能化是未来振动能采集微电源的研究趋势.     

封闭式波浪能发电装置受力与俘能功率研究

为开发低能流密度海域波浪能应用潜力,对新型封闭式波浪能发电装置开展受力及俘能功率进行研究。基于三维势流辐射-绕射理论,运用时域分析法,研究了质量对5～20 m浮标直径的封闭式波浪能发电装置F-K力、波浪绕射力和俘能功率的影响。研究发现,在8～14 t的质量要求范围内,随质量的增加,F-K力和波浪绕射力最大增加了127%和88%,俘能功率增加了23.5%～47%。研究结果表明,质量对封闭式波浪能发电装置的受力和俘能功率具有显著影响,通过增加质量的方式可提高波浪能发电装置的俘能功率。该研究可为波浪能发电装置材料选择、功率提升提供理论依据和方法,对开发低能流密度海域波浪能资源具有一定的推动作用。     

微小型波浪能发电机的发展

随着陆地资源的消耗殆尽,蕴藏于海洋中的波浪能作为绿色可再生的能源逐渐引起了人们的重视。虽然早在上世纪70年代世界各国就相继研发出了各种波浪能转化装置,但是利用率都不高,且体型庞大。本文对比了当前存在的波浪能发电机的优缺点,对微小型波浪能发电机进行了探讨。     

太阳能的利用

研究难度: 复杂 适合人群: 高中生关于太阳能利用的概况太阳能是各种可再生能源中最重要的基本能源。太阳能作为可再生能源的一种,是指太阳能的直接转化和利用。通过转换装置把太阳辐射能转换成热能利用的属于太阳能热利用技术,再利用热能进行发电的称为太阳能热发电,也属于这一技术领域;通过转换装置把太阳辐射能转换成电能利用的属于太阳能光发电技术,光电转换装置通常是利用半导体器件的光伏效应原理进行光电转换的,因此又称太阳能光伏技术。20世纪50年代,太阳能利用领域出现了两项重大技术突破:一是1954年美国贝尔实验室研制出6%的实…     

飞机液压系统余度设计及系统间隔离与连接技术综述

介绍了常见飞机液压系统,从液压能源、液压回路等方面简述了飞机液压系统的余度设计,分析了不同飞机液压余度设计的特点,指出为提高飞机液压回路系统的利用率,采用互通互联式液压回路也是飞机液压回路余度设计的一个发展方向,并介绍了能源转换装置、能源选择阀、液压保险等各种系统互连互通和隔离装置.     

耳夹式可穿戴体征参数感测装置的设计

近年来,可穿戴设备逐步受到医疗领域的关注,而消防部队承担的应急救援工作任务日益繁重,确保消防官兵在灭火救援行动中的人身安全具有极其重要的现实意义。为此设计了一种基于消防安全的耳夹式可穿戴装置,通过光电转换方式采集脉搏波信号,然后采用CC2640滤波处理后得到血氧饱和度和脉率的体征参数,再通过无线蓝牙将数据传输,从而实现消防指挥中心对消防员身体状况的实时监测。该装置具有体积小、重量轻、功耗低及可穿戴的特点,可应用于消防、公安等部门。     

基于FPGA的谐振音叉高速信号采集装置的搭建

谐振音叉作为一种重要的谐振敏感元件,其输出信号直接体现了其频率特性,且直接决定了谐振式传感器的性能,所以对谐振音叉输出信号的研究具有重要意义。本文搭建了一套基于FPGA的高速信号采集装置来进行音叉信号的采集和处理。该装置由硬件部分和软件部分组成,其中硬件部分主要包括电荷放大、滤波、电平转换、模数转换、FPGA信号解算单元及串口调试单元等;软件部分则包括下位机软件和上位机软件。为了对装置性能进行测试,本文采用实验室实际的音叉样件进行实验,通过对其输出信号的拾取和信号处理,测得该装置测试精度可达到0.2%。这样的实验结果表明该装置可满足谐振音叉在1 kHz~30 kHz范围内频率特性的测量要求,且性能良好。     

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。     

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.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。