基于霍尔传感器微阵列的呼吸频率检测系统设计

基于呼吸感应体积描记技术原理,在一条腹带内部嵌入了永磁铁,腹带系在患者腰部,在呼吸过程中,由于体积的变化引起腹带中永磁铁的位置运动,通过霍尔传感器阵列对永磁铁位置进行检测,从而判断呼气和吸气的过程,采用单片机对传感器信号进行分析处理,计算出呼吸频率。经10名受试者重复实验,并与呼吸检测设备的检测结果进行比较,本系统的平均精确度高于95%,证明了本系统的可靠性。所设计的呼吸频率检测系统可用于睡眠呼吸检测仪、慢呼吸高血压治疗仪等设备。     

一种肺呼吸电阻抗实时成像系统

介绍了一套用于肺呼吸过程电阻抗实时成像的16电极EIT系统,描述了该系统的软硬件设计、系统性能测试及利用共轭梯度算法进行成像试验。在盛有盐水的实验水槽上进行了有机玻璃棒的动态成像实验,结果表明该系统能够对动态目标进行准确识别。采集志愿者呼吸过程的数据,并对肺呼吸图像重建中胸腔模型对成像质量的影响进行了对比试验,最终获得了清晰的肺部呼吸过程的图像,为深入开展肺功能评价研究及呼吸过程的床旁监护等需求奠定了可靠有效的硬件基础。     

一种供氧面罩防窒息活门测试系统的设计研究

针对供氧面罩防窒息活门性能检测,及其对人体呼吸模式影响的研究需求,研制了多参数采集、分析及统计一体的供氧面罩防窒息活门测试系统。该系统基于CompactDAQ平台,以面罩压、通气流量信号采集为基础,采用LabVIEW软件开发,可对开启压力、吸气阻力、通气流量峰值、潮气量、呼吸频率等参数进行分析统计。通过实验验证,该系统具备了对防窒息活门主要性能检测,及人体呼吸参数分析统计的能力。该系统便于携带,扩展性强,人机界面友好,运行可靠,较好的满足了防窒息活门检测、研究的需求,同时该系统的设计方法为供氧面罩其他性能参数的检测的提供了一种思路     

基于LabVIEW飞机地面逆变电源暂态特性测试系统

为研究飞机地面逆变电源暂态特性,保证飞机用电设备的可靠运行,研究了一种飞机地面逆变电源暂态特性测试系统;该测试系统基于国际标准和民航标准对于航空地面电源电压品质的要求;采用虚拟仪器技术,设计硬件电路,构建一套完整的地面电源暂态特性的测试系统;本实验中对APS6000-45KVA型号的飞机地面逆变电源进行测试,验证了该地面电源暂态特性;研究结果可用于国内飞机地面逆变电源暂态特性的检测,保障飞机地面用电的同时为飞机地面逆变电源的检修提供依据。     

基于部位检测和子结构组合的行人检测方法

提出了一种基于部位检测和子结构组合的、可用于辅助驾驶或视频监控系统中行人检测的方法.首先使用头部分类器在整幅图像中检测,得到感兴趣区域;然后在每个感兴趣区域内使用头部、躯干、腿部以及左臂和右臂5个人体部位检测器分别检测并使用基于子结构的检测组合方法对部位检测结果进行组合,以得到最终结果.在不同数据库上的实验结果表明,本方法可以有效地用于移动或静止摄像机所拍摄的视频图像中的多姿态及部分遮挡的行人检测.     

超声波传感器在混凝土无损检测系统中的应用研究

设计了一种用于混凝土无损检测的超声波检测仪,介绍了超声波检测的基本原理和系统设计,着重讨论了其发射系统和接收系统的设计方案,进行了无缺陷和有缺陷混凝土灌注桩的测试实验,并对测试数据及波形分析处理.从实验结果表明,该测试仪检测混凝土缺陷快速准确,误差小,具有一定的实用价值.     

基于电容式传感器的建筑物围护结构含水率测试

设计的平面电容式传感器可感应围护结构中水分的变化,给出了传感器的工作原理,针对小电容检测的抗干扰问题,采用了加保护电极和利用驱动电缆传输信号的技术,结合改进的充放电微电容检测电路,对传感器的测试深度和灵敏度与极板尺寸的关系进行了研究和优化。设计了基于嵌入式微控制器的含水率测试系统,实验结果表明:该系统可以用于一定深度的围护结构的含水率现场测试。     

基于快速响应湿度传感器的无线呼吸检测系统

呼吸功能的实时检测对有呼吸功能障碍的人群十分重要.基于纳米材料湿度传感器和Zig Bee无线网络技术设计了一种呼吸检测系统,该系统由四部分组成:湿度传感器探头、数据采集节点、数据接收节点、基于VC++的MFC平台开发的呼吸功能检测软件.系统实现了呼吸频率记录、呼吸暂停报警、呼吸信号波形实时显示等功能.实验对几位志愿者进行呼吸功能检测,验证了系统的有效性.呼吸检测系统具有响应和恢复快、能够检测急促呼吸、受外界干扰小、无线检测、携带性强等特点.     

基于虚拟仪器的传感器性能测试系统

为检测传感器性能是否符合需求,在傅里叶级数算法原理的基础上,结合虚拟仪器技术,开发设计了传感器性能测试系统。通过实验验证了该测试系统能有效地对传感器性能进行检测,误差约为0.004,同时测试系统还具有一定的可扩展性和通用性,用于实验传感器以外的其他传感器测试。     

基于Kinect的非接触式呼吸检测系统

利用Kinect的深度传感器功能,获取景深图像,并对图像进行信号处理和分析,检测人体的呼吸率和呼吸状态,从而实现非接触式呼吸检测.该系统免除了传统接触式呼吸检测仪安装和测试带来的不便,实现高效准确的实时呼吸监测.     

Monitoring of melanoma released volatile compounds by a gas sensors array: From in vitro to in vivo experiments

The analysis of the volatile organic compounds (VOCs) released by bio-systems represents a promising approach for the diagnosis of human diseases including cancers. Experimental results suggested the possibility to detect tumors in vivo through the analysis of released VOCs from different body compartments, such as breath and skin. This paper illustrates the results obtained measuring VOCs mixtures released by well-characterized tumor cells derived from human malignancies by using an array of broadly selective chemical sensors. The patterns of VOCs emitted by two different melanoma tumorigenic cell lines transplanted ad hoc in a mice model were investigated. The recorded sensors signals are compatible with the existence of a distinguishable tumor specific pattern of VOCs evolving during the exponential phase of tumor growth.     

Optical VOCs detection using poly(3-alkylthiophenes) with different side-chain lengths

The use of conjugated polymers in the gas and volatile organic compounds (VOCs) detections represents an advance in the development of the electronic noses. Polythiophenes show good thermal and environmental stability, are easily synthesized and they have been studied as gas and VOCs sensors using different principles or transduction techniques. Among these techniques, optical sensing has been attracted attention, mainly due to its versatility. However, conjugated polymer-based optical sensors are still less studied. This paper describes the use of two poly(3-alkylthiophenes) for VOCs optical detection. The sensing measurements were carried out using visible spectroscopy. Both polymers showed good sensitivity to the VOCs, showing fast and reversible responses with some hysteresis, and were unable to detect hydroxylated samples. Furthermore, it was demonstrated that the thickness of polymer films influences the intensity of the optical response. Although there is similarity in the superficial composition of the polymers films, demonstrated by their surface energies, they showed significant differences in their optical properties upon exposure to the VOCs.     

Sparse representation-based classification for breath sample identification

It has been discovered that some compounds in human breath can be used to detect some diseases and monitor the development of the conditions. A sensor system in tandem with certain data evaluation algorithm offers an approach to analyze the compositions of breath. Currently, most algorithms rely on the generally designed pattern recognition techniques rather than considering the specific characteristics of data. They may not be suitable for odor signal identification. This paper proposes a Sparse Representation-based Classification (SRC) method for breath sample identification. The sparse representation expresses an input signal as the linear combination of a small number of the training signals, which are from the same category as the input signal. The selection of a proper set of training signals in representation, therefore, gives us useful cues for classification. Two experiments were conducted to evaluate the proposed method. The first one was to distinguish diabetes samples from healthy ones. The second one aimed to classify these diseased samples into different groups, each standing for one blood glucose level. To illustrate the robustness of this method, two different feature sets, namely, geometry features and principle components were employed. Experimental results show that the proposed SRC outperforms other common methods, such as K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA), Artificial Neural Network (ANN), and Support Vector Machine (SVM), irrespective of the features selected.     

湖北省四湖地区湖泊水域近期变迁的遥感应用研究

利用不同时期的Landsat MSS和TM图像对本世纪50年代以来研究区湖泊水域的面积变化进行了研究。结果表明,该区湖泊面积持续减少;50年代初期至70年代末期期间的减幅远大于80年代以来的减幅。湖泊减少的原因,首推人类活动,自然因素也起到了重要作用。在调查研究的基础上,对合理利用与保护湖泊资源的对策进行了探讨。     

Validation of an industrial analytical sensor procedure realized with a SAW-based sensor system

Mass-sensitive sensors based on surface acoustic waves (Suface Acoustic Wave Devices, SAWs) can be used for qualitative as well as for quantitative determination of volatile organic compounds (VOCs). An analytical procedure for a SAW-based sensor system used for on-line process control of VOCs in pharmaceutical industry was developed. Analytical procedures applied in pharmaceutical development and production have to meet the requirements of good manufacturing practice (GMP) and therefore a validation in compliance with the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH)-guidelines had to be performed. It is shown that these procedures can be successfully validated as non-chromatographic procedures according to ICH-guidelines. As a typical example, the on-line control of a HPLC gradient former was investigated. In this particular case, the sensor system has to determine the actual composition of the mobile phase and furthermore it has to discriminate possible avoidance. The following analytical performance parameters are investigated to prove the validation of the analytical procedure: Specificity, Linearity, Limit of Detection and Quantitation, Accuracy, Precision, and Robustness.     

基于QRSCU方法的RHD基因的偏好性研究及其应用

Rh血型系统作为人类最复杂的血型系统之一,其临床意义仅次于ABO血型系统.研究人类Rh血型系统中RHD基因对同义密码子的使用偏好性有助于从生物信息学角度了解RHD基因的编码特征.本文基于拟氨基酸编码方法,计算了人类Rh血型系统中RHD基因的同义密码子的相对使用度(quasi relative synonymous codonusage,QRSCU)及4种碱基分别出现在密码子3'端的相对频率(quasi relative frequency of nucleotide to codon3',QRFN3').通过分析计算结果中RHD基因的QRSCU值,得出RHD基因偏好使用以C或G结尾的同义密码子,也说明RHD基因偏好使用密码子-反密码子结合作用强的同义密码子,且避免使用结合作用中度的同义密码子.另外,通过分析计算结果中RHD基因的ORFN3'值,得出RHD基因的同义密码子对后面所接的第一个碱基的使用也有很强的使用偏好性.     

VOCs在线检测质谱仪单光子电离源的研制

该文介绍了两个不同结构的真空紫外单光子电离源(SPI),电离源与自制的飞行时间质谱仪(TOFMS)连接实现了对挥发性有机物的在线检测。在搭建的SPI-TOFMS上比较了两个电离源的电离效率之间的差异。虽然轴向SPI本质上不是一个纯粹的单光子电离源,但可明显看出,其电离效率比径向SPI要高约50%。同时还考察了仪器的部分性能指标。在质荷比(m/z)为92位置,质量分辨率达767;在1谱/s分析速度下,检测限低于20×10-9(v/v)。实验结果证明该仪器能够用于挥发性有机物的在线检测。     

Adaptive neuro-fuzzy inference system employing wavelet coefficients for detection of alterations in sleep EEG activity during hypopnoea episodes

The Obstructive Sleep Apnoea Hypopnoea Syndrome (OSAH) means “cessation of breath” during the sleep hours and the sufferers often experience related changes in the electrical activity of the brain and heart. This paper describes the application of adaptive neuro-fuzzy inference system (ANFIS) model for automatic detection of alterations in the human electroencephalogram (EEG) activities during hypopnoea episodes. Decision making was performed in two stages: feature extraction by computation of wavelet coefficients and classification by the ANFIS trained with the backpropagation gradient descent method in combination with the least squares method. The EEG signals (pre and during hypopnoea) from three electrodes (C3, C4 and O2) were used as input patterns of the three ANFIS classifiers. To improve diagnostic accuracy, the fourth ANFIS classifier (combining ANFIS) was trained using the outputs of the three ANFIS classifiers as input data. The proposed ANFIS model combined the neural network adaptive capabilities and the fuzzy logic qualitative approach. Some conclusions concerning the saliency of features on detecting any possible changes in the human EEG activity due to hypopnoea (mild case of cessation of breath) occurrences were drawn through analysis of the ANFIS. The performance of the ANFIS model was evaluated in terms of training performance and classification accuracies and the results confirmed that the proposed ANFIS model has potential in detecting changes in the human EEG activity due to hypopnoea episodes.     

热计量与温湿度调节装置中最佳温湿度匹配库的建立

利用CMAC神经网络算法简单、学习速度快、易于软件实现的特点,在智能型热量计量与温湿度调节一体化装置中实现了最佳温湿度匹配库的建立;对用户的温湿度匹配值进行学习、联想记忆,满足了不同人的舒适性的要求;在基函数为1的情况下,可大大简化编程;运行结果表明,该方法学习速度快、精度高,在以人为本的人居环境控制中具有广阔的应用前景。     

基于SAW表面气液相效应和GC分离柱的气敏传感器的研究

限于传统涂敷敏感膜的声表面波（SAW）气敏传感器存在成膜困难和选择性差、重复性差以及再生性差等问题，本研究提出一种基于压电基底表面气体气液相转换效应机理的瑞利波传感器。首先建立了挥发性有机气体(VOCs)液相凝聚体薄层负载下的SAW波传模型，并仿真计算了其波传频散和波传衰减。然后在此基础上开发了一种基于瑞利声表面波传感器和气相色谱（GC）分离柱的便携式气体检测系统。最后实验论证了方案的可行性，初步的实验结果表明该系统具有分析时间短、选择性好、灵敏度高（可检测ppb浓度的混合VOCs）以及成本低等优势，因此其在痕量挥发性有机气体检测和分析应用上有良好的潜力和前景。