人体三维建模和超声人体通信的仿真研究

为了实现无线健康监测,人体通信技术发展迅速.然而,人体是电磁波信号传输的障碍物,盲目增大电磁波辐射场不利于人体安全.长期临床应用证明超声在人体组织的穿透性能优于电磁波且对人体无害.但现有二维模型在仿真人体内信号传输多径效应上受限.为此提出按照人体组织的层次结构建立三维人体模型,用K空间方法解决了传统方法中模型复杂度高的问题,提高了仿真速度和仿真效率.通过仿真对比实验,测试不同类型的信号、不同信号频率和不同人体组织的传输特性,找到了应对人体信道多径效应和高衰减问题的通信方法,最终对体内跨组织传输场景进行仿真.结果表明,600KHz的调相信号可实现跨越不同人体组织的信号传输,利用超声实现人体通信是安全可行的.     

1090MHz数据采集传输系统的实现

为探究1090MHz信道占用情况及信道内信号传输情况,设计开发了1090MHz数据采集传输系统。系统采用现场可编程逻辑门阵列(FPGA)与单片机(STM32)实现1090MHz信号的采集与传输;采用C++语言编写上位机软件,实现对数据采集部分的远程控制及数据的存取和显示。采集1090MHz频段的主要信号(ADS-B信号与二次雷达信号),初步观察信号的信道占用率及交织、受干扰情况,将数据有选择的保存至数据库进行后续分析。最后,在真实环境中采集1090MHz信号进行了测试,测试结果表明,该系统能够根据设置的命令参数采集传输1090MHz信道内的主要信号,实现了对信道实际状况及信道内信号传输情况的初步监测。     

一种应用在人体传感器网络的低功耗VCO

人体通信作为人体传感器网络的一种新兴的通信方式,有着突出的优势与巨大的潜力.介绍了应用在人体通信无线收发器的压控振荡器(VCO)的设计与测试.该模块采用了四级双差分结构,采用SMIC 0.18 μm 1P6M工艺,核心面积仅为0.02 mm2.测试结果显示:在1.8V供电电压下,VCO调谐范围为30～130 MHz,在80 MHz输出频率下,1 MHz频偏处相位噪声为-98 dBc/Hz,最大功耗仅为1.27 mW,较好地满足了采用人体通信作为通信方式的人体传感器网络的要求.     

人体心电监护物联网节点研究与实现

针对物联网技术发展新趋势对人体心电监护作了进一步研究,将无线传感器网络与互联网连接起来,进行心电信号的信息交换和通信。详细描述了用于心电监护的物联网节点硬件电路设计,完成了基于NesC语言的组件结构化软件设计,并在节点数据路由协议LEACH基础上提出了改进型路由协议LEACH-SA。实验结果表明人体心电监护物联网节点能够有效地对人体心电信号进行数据采集和传输。     

斜井人车漏泄通信及监控系统

斜井人车漏泄通信及监控系统是一种基于漏泄通信传输原理、综合话音通信、联络信号和人车实时监测为一体的通信及监控系统。该系统是在ＫＴ６通信系统应用的基础上，进一步开发信号和监测功能，使得该系统具有人车与绞车房的话音通信、人车向绞车房发打点联络信号和紧急告警信号及人车车位车速实时监测等功能。该系统与已有的基于感应通信传输原理的斜井通信信号装置相比有较大的优越性。     

电梯无线召唤通信系统设计与实现

针对传统电梯厅召唤通信系统布线复杂、调试、维护不便等问题,设计一个以Si4460芯片为核心的射频电梯无线厅召唤通信系统。该系统以M0516为主控芯片,结合Si4460为核心的射频模块,搭建433 MHz频率的无线通信网络,实现厅层终端节点与电梯主控制器之间信息的无线传输。在该系统中,厅层终端与协调器以433 MHz无线收发数据,而协调器节点与电梯主控器通过RS485接口通信。从整体设计方案、硬件设计、软件设计和性能测试4个方面对系统进行阐述,实验结果证明,该系统已实现电梯厅召唤的基本功能,在电梯不同运行状态下都能达到良好的信号传输性能,不受电梯井道电磁干扰环境的影响。     

基于涡旋电磁波的大容量通信系统设计

鉴于涡旋电磁波所体现出的独特空间电磁场分布特征,以及其携带的轨道角动量在理论上所具有的无穷维度模态正交特性,涡旋电磁波在无线通信领域和雷达探测与成像领域均表现出重要的研究价值和应用潜力;通过涡旋电磁波空间电磁场的分布和原理入手,采用在C波段设计阵元交替排布的双圆环均分天线阵列,并基于带状线屏蔽性能强的优势设计4路1分8的叠层馈电网络,从而产生4种混合模态(+1,-1,+2,-2)的涡旋天馈系统;通过搭建混合模态涡旋电磁波大容量通信系统测试收发天馈之间模态隔离度大于15dB,在此基础上加入软件无线电平台验证通信系统多路涡旋波信号传输特性,测试验证4个端口均可正确接收、解调电磁信号,实现频谱效率4倍的提升。     

基于Zigbee的人体心电信号无线监测系统的设计

提出了一种基于Zigbee技术的人体心电信号无线监测系统设计方案;采用Zigbee技术和STM32W108ARM芯片设计了系统采集节点和汇聚节点的硬件电路,采用C语言编写了其软件,实现人体心电信号的采集和无线传输;利用Labview软件设计人体心电监测界面,实现了利用PC机对采集到的心电信号进行实时监测;实验表明,该监测系统通信质量良好,能够实现心电信号的采集、波形显示,以及心率值和心电频谱的分析,在家庭医疗领域具有较高的应用价值。     

基于多级混沌同步理论的保密通信

提出了一种多级混沌同步保密通信系统实现方案。在发射端，混沌信号首先与有用信号进行合成，然后将合成的混沌信号作用于另一个混沌系统，进而得到调制后的传输信号；在接收端，信道传输的混沌信号经过与发射端结构相同的混沌系统二级解调后恢复出有用信号。研究结果表明，这种多级混沌同步保密通信系统比原同步掩蔽通信系统具有更好的安全特性和更高的有效带宽，而且实现简单。     

考虑基带噪声干扰的光纤传感通信信号隐匿传输方法

光纤传感通信技术是以光波为载体,利用光纤传播信息的通信方式。但在隐匿传输过程中易受信号强度、基带噪声、传感器性能等因素的影响,导致信号数值波动大、传输精度低。因此,提出考虑基带噪声干扰的光纤传感通信信号隐匿传输方法。采用局域波分解技术剔除信号中的基带噪声,根据压缩感知技术对信号实行一层压缩处理,利用随机投影算法实现信号的二层压缩与重构,并通过计算信号的传送数据向量与接收数据向量,完成光纤传感通信信号的隐匿传输。仿真结果表明,所提方法的序列估计误差最小值为0.17,引入噪声后的信号序列相关峰均比高达89dB,误码率控制在0.5%,安全容量始终高于2.7bit/s,匿名度为0.62,具有较好的隐匿传输效果。     

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。     

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。