基于K-最近邻算法的管道系统传感器数据有效性分析研究

在管道运输中传感器的正常使用至关重要,为了防止因传感器故障而导致的数据采集失效,造成误报警和漏报警,对传感器本身的故障诊断和失效分析已经成为当前研究的重要方向.通过对各传感器采集数据进行组合分析,以各传感器之间的数据关联特性作为研究内容,运用K-最近邻算法对管道上传感器所采集数据进行相似性拟合,提出采用C4.5算法定义各传感器所采集数据对目标传感器的支持度以决定目标传感器数据的有效性,对故障传感器运行状态进行分析与定位,进而判断传感器的数据可靠性和输差出现位置.实验结合西南某管道流量传感器数据进行分析,结果表明,该算法能够准确判断目标传感器数据的有效性和故障传感器在时域中发生的位置.     

基于神经网络预测器的传感器数据证实技术研究

提出了基于神经网络预测器的传感器数据证实技术。首先利用神经网络对传感器输出的时间序列建立预测模型,然后利用该模型预测出传感器输出值,并用该值与传感器实际输出值之差判断传感器实际输出的可靠性和有效性,进而减小传感器“软故障”和不同环境噪声对传感器输出数据的影响。同时,为了实现在线应用,采用了遗传算法对神经网络的优化技术。     

新型传感器技术在武器系统中的应用

新型传感器技术是现代武器装备发展与技术更新的重要保障条件,在军事工程和国防建设中占有重要的地位。评述了MEMS传感器、红外传感器、图像传感器、光纤传感器、智能传感器和网络传感器等新型传感器技术,介绍了新型传感器技术在军用无线传感器网络、智能灰尘、微型机器人等武器系统中的应用,并对新型传感器技术的发展趋势进行了展望。     

无线传感器网络拓扑优化研究

无线传感器网络是新兴的下一代传感器网络,可以预计,无线传感器网络的发展和广泛应用,将对人们的社会生活和产业变革带来极大的影响和产生巨大的推动。路由技术是无线传感器网络通信层的核心技术,对无线传感器网络的拓扑研究将具有重要的现实意义。     

基于遗传算法的传感器动态特性改善方法

在动态测试中一些传感器的动态特性不能满足测试需求。为了改善传感器的动态特性提出了一种改进自回归模型,采用梯度下降法和遗传算法对其参数进行优化,通过对传感器进行逆建模来实现对传感器动态特性的改善。对腕力传感器的动态特性进行了改善并分析了传感器改善前后的时域和频域特性。在matlab平台对6阶系统的动态特性进行了改善。实验结果表明对CY-YD-205压电传感器动态特性的改善效果要比最小二乘法好。     

无线传感器网络(WSN)安全综述

无线传感器网络是自动化、通信工程和计算机科学技术学科中的一个新的研究领域,是一项应用于监视和侦察的技术,具有广阔的应用前景。随着传感器网络在各个领域地不断应用,其安全问题日益突出。但是在迄今的无线传感器网络研究和发展过程中,对其安全问题考虑较少。本文在介绍传感器网络有关知识的基础上,研究了传感器网络的安全技术。主要工作如下:1.分析了传感器网络面临的各种攻击,结合传感器网络自身特点提出了传感器网络的安全需求。2.分析了传感器网络中的对密钥管理方案,比较了各种对密钥管理方案的优缺点。3.给出了一种针对传感器网络的安全加密协议,并对该协议的一些实现问题及其特点进行了分析。     

空间传感器节点定位方法研究

无线传感器网络能够实时监测、感知和采集各种环境和检测对象的信息,但无线传感器节点在使用的过程中需要对其进行维护,而在投放传感器节点时,往往没有记录传感器节点的投放空间坐标或者由于其他因素导致传感器节点在投放后位置发生了改变,在这样的情况下,就需要对传感器节点进行定位。介绍一种传感器空间节点定位的方法,并对其误差及改进方法进行了讨论。     

智能传感器在汽车上的应用

智能传感器是传感器极为重要的发展方向。介绍了智能传感器的基本概念和在汽车领域几个主要系统的应用,并通过对智能传感器的发展阶段和发展市场分析,展望了汽车智能传感器的发展趋势。     

MEMS传感器——无人机的核心

无人机的市场规模和范围持续蓬勃发展,新应用程序不断涌现,而高品质MEMS传感器和先进软件对其发展至关重要。本文详细介绍了无人机的几种关键性传感器以及对无人机性能的影响,如惯性测量单元、气压传感器、地磁传感器、应用特定型传感器节点和传感器数据融合,并介绍了Bosch Sensortec的相关产品在无人机上的应用。     

传感器技术在电网中的应用评述

传感器技术作为重要的信息采集技术,在电网中的应用越来越广泛,由于电网应用场景的特殊性,也在影响着传感器技术应用的深度和广度。介绍了传感器技术的国内外发展现状;对传感器技术在电网中的应用现状进行了阐述,并结合实际应用情况,对传感器技术在电网应用中面临的问题进行了评述和分析。最后对传感器技术在电网中的应用进行了总结和展望。     

Analysis of various factors affecting the non-Markovian dynamics associated with a hierarchical environment based on collision model

We propose a quantum collision model in which the environment is abstractively divided into two hierarchies including “environment-bus” that has direct interactions with the system and “environment-stations” that has not. Based on the model, we investigate the effects of initial system–environment correlations, initial states of environment, and various interactions on the dynamics of open quantum systems associated genuinely with such a hierarchical environment. We illustrate that the initial quantum correlation between the system and environment leads to a transition from Markovian to non-Markovian dynamics, while for initial classical correlation the transition can only be confirmed to happen when the couplings rather than the correlations in environment are present. In addition, we investigate the degree of non-Markovianity varying with environment initial states and reveal that the interaction strength between two environmental hierarchies plays an important role in it. In particular, we show that in such a hierarchically structured environment the degree of non-Markovianity is not equivalent to memory effects of the environment-stations as a reservoir due to the presence of the environment-bus.     

2D artificial life system using network-type assembly-like language: influence of change in environment with costs of instructions

To unlock the full potential of evolution in digital media, a Tierra-like system using network-type assembly-like language has been constructed. In the system, like Avida, digital creatures, self-replicating programs, live in a discrete 2D torus space and an interaction between creatures is restricted locally. Bearing a genetic network in mind, network structure is introduced. In the previous works, it is shown that the possibility that the network-type model has more potential of evolution than a linear-type model like Avida in a simple environment. In this paper, to study the potential of evolution more precisely, we model the effects of environment other than creatures. As one of the simplest models of such environment, the cost of execution, i.e. executing time, is introduced. The difficult environment to live in costs high to execute instructions, the easy environment does low. In computer experiments, we have investigated the influence of change in environment by analyzing the process of evolution and diversity of the system. Experimental results show that the network-type system keeps more stable diversity than the linear-type system does, even when the environment changes drastically. This indicates the possibility that the network-type system has more potential of evolution than the linear-type system has. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Assessment of the effectiveness of the educational environment supported by computer aided presentations at primary school level

The objective of this study is to assess the effectiveness of the educational environment supported by computer aided presentations at primary school. The effectiveness of the environment has been evaluated in terms of students’ learning and remembering what they have learnt. In the study, we have compared experimental group and control group in terms of learning and recalling what has been learned regarding the effect which computer aided learning environment imposes. Data have been collected through the control grouped pretest–final test model. During the experiment, we have prepared an achievement test, which explains behaviors the students should acquire. According to the findings obtained, a computer aided educational environment has been observed to be more effective than that of conventional education in terms of learning. However, in terms of the permanence of what has been learned, no meaningful difference between the educational environment supported by computer aided presentations and that of conventional education has come out. According to the results of the follow-up tests performed, even though students in the test group have forgotten more of what they have learnt, it has been concluded that students in both groups have forgotten on the same level. Consequently, it has been observed that though the educational environment supported by computer aided presentations has positive contributions to learning activity, it does not have effects on the permanence of what has been learnt.     

Assessment of the effectiveness of the educational environment supported by computer aided presentations at primary school level

The objective of this study is to assess the effectiveness of the educational environment supported by computer aided presentations at primary school. The effectiveness of the environment has been evaluated in terms of students’ learning and remembering what they have learnt. In the study, we have compared experimental group and control group in terms of learning and recalling what has been learned regarding the effect which computer aided learning environment imposes. Data have been collected through the control grouped pretest–final test model. During the experiment, we have prepared an achievement test, which explains behaviors the students should acquire. According to the findings obtained, a computer aided educational environment has been observed to be more effective than that of conventional education in terms of learning. However, in terms of the permanence of what has been learned, no meaningful difference between the educational environment supported by computer aided presentations and that of conventional education has come out. According to the results of the follow-up tests performed, even though students in the test group have forgotten more of what they have learnt, it has been concluded that students in both groups have forgotten on the same level. Consequently, it has been observed that though the educational environment supported by computer aided presentations has positive contributions to learning activity, it does not have effects on the permanence of what has been learnt.     

PIRF-Nav 2.0: Fast and online incremental appearance-based loop-closure detection in an indoor environment

This paper presents a fast and online incremental solution for an appearance-based loop-closure detection problem in a dynamic indoor environment. Closing the loop in a dynamic environment has been an important topic in robotics for decades. Recently, PIRF-Nav has been reported as being successful in achieving high recall rate at precision 1. However, PIRF-Nav has three main disadvantages: (i) the computational expense of PIRF-Nav is beyond real-time, (ii) it utilizes a large amount of memory in the redundant process of keeping signatures of places, and (iii) it is ill-suited to an indoor environment. These factors hinder the use of PIRF-Nav in a general environment for long-term, high-speed mobile robotic applications. Therefore, this paper proposes two techniques: (i) new modified PIRF extraction that makes the system more suitable for an indoor environment and (ii) new dictionary management that can eliminate redundant searching and conserve memory consumption. The results show that our proposed method can complete tasks up to 12 times faster than PIRF-Nav with only a slight percentage decline in recall. In addition, we collected additional data from a university canteen crowded during lunch time. Even in this crowded indoor environment, our proposed method has better real-time processing performance compared with other methods.     

Experience report: evolution of a web‐integrated software development and verification environment

This paper summarizes our experiences over the last 4 years in creating a web‐integrated software development and verification environment. The environment has been used for both research experimentation and education. It has been used in undergraduate computer science courses to teach modular software development and analytical reasoning principles at multiple institutions. In the process, the environment has undergone many refinements to meet demands for improved functionality and to leverage rapidly changing underlying technology for the improvements. The environment is tailored to present formal specifications and alternative implementations of components, and enable correctness checking through a server‐side verifying compiler. This paper presents a detailed account of the development and evolution of the environment—its functionality, user interface, and underlying technology—that we hope will serve as a model for others, especially as the benefits of online learning systems are becoming increasingly obvious. Copyright © 2014 John Wiley & Sons, Ltd.     

Delphi中OpenGL三维仿真开发环境设计及应用

主要对Windows环境中使用Delphi及OpenGL三维仿真开发环境建立的方法进行了研究。首先介绍了OpenGL图形库的功能、特点以及OpenGL在Win32环境中的运行机制;然后详细阐述了在Windows环境下使用Delphi及OpenGL联合编程,建立三维仿真开发环境的实现过程;并将这一仿真开发环境在战斗部虚拟测试系统仿真软件中进行了综合应用。用OpenGL图形库进行三维仿真,真实感强,因而具有较高的使用价值和良好的应用前景。     

VB6.0在火焰检测监控系统通信中的应用

提出了通过VB6.0构建火焰检测监控系统的软件平台,重点介绍了VB6.0的通信控件MSComm,并通过该控件实现上位机和下位机的通信,同时给出了部分的通信程序.通过实际运行证明,基于VB开发环境,使用串行通讯来实现的监控系统具有较高的实时性和可靠性.     

多特征相结合的带噪语音端点检测算法的研究

提出了一种抗噪声的端点检测新方法。针对谱熵特征对清音的检测性能以及抗噪声性能较差的缺点,结合对清音检测性能较好的短时过零率特征,以及抗噪声性能良好的美尔倒谱距离特征,实现了基于多种特征相结合的抗噪声的语音端点检测。仿真实验表明,该方法能显著提高端点检测在高噪声环境下的检测性能。     

VFRS:一种面向虚拟计算环境的入侵容忍方法

虚拟计算环境的开放性、复杂性和动态性向入侵容忍提出了新的挑战,提出VFRS方法以解决虚拟计算环境中数据对入侵的容忍问题.设计SCSFA算法分析虚拟计算环境的系统调用行为序列,以识别虚拟计算环境下的入侵企图,预测敏感数据的高危区域;其次,将要保护的数据划分成若干片数据,并以容忍虚拟计算环境随机错误为目标对每个片数据冗余备份;然后将冗余片数据分散到不同虚拟机上.VFRS方法能有效预测虚拟计算环境下的异常入侵,并能较好地容忍虚拟计算环境下的复杂性错误.对VFRS方法实现的关键问题进行了详细的讨论和分析.