基于PVDF的可穿戴鼾声监测系统

阻塞型睡眠呼吸暂停综合征(OSAS)是常见的睡眠类疾病,为满足居家对OSAS进行初步筛查和诊断,该文设计了基于聚偏氟乙烯(PVDF)压电薄膜的鼾声监测系统。可穿戴式的鼾声监测系统包含高灵敏度鼾声传感器、低噪声信号调理电路、嵌入式系统及上位机系统。根据鼾声段和非鼾声段能量差异大的特点,基于短时能量法进行鼾声端点检测算法设计,通过采集的鼾声信号进行算法验证。经测试,系统采集的鼾声信号信噪比高,端点检测平均误差小于0.032 s,准确率达92.6%,满足潜在OSAS患者的筛查要求以及进行康复训练的自我检查,同时可减轻患者筛查和医学多导睡眠图(PSG)检测的负担。     

基于PVDF的可穿戴生理信号监测系统

呼吸、心率、鼾声反映了人体在睡眠时的大量信息,该文以聚偏氟乙烯(PVDF)作为敏感单元进行呼吸、脉搏、鼾声信号的监测。根据所采用的传感器特性分别进行了电荷放大电路、陷波电路及电压放大电路的设计。硬件电路通过聚合物锂电池进行供电,根据聚合物电池的特性分别为电池设计了充电电路、保护电路及放电电路,硬件电路整体集成在一块印制电路板(PCB)上。同时设计了基于Android 设备的APP,以可视化形式实时显示生理信号数据,并对其进行长期储存,便于后期医生进行睡眠呼吸病症的分析诊断。该研究的目的是能准确监测睡眠生理参数,提高被测试者的使用舒适感。     

Design and Validation of Wearable Smartphone Based Wireless Cardiac Activity Monitoring Sensor

Wireless Personal Communications - Due to technological advancements in electronics industry, wireless sensors in conjunction with mobile phones can be used anytime anywhere for ubiquitous...     

Flexible Hybrid Electronics: Direct Interfacing of Soft and Hard Electronics for Wearable Health Monitoring

The interfacing of soft and hard electronics is a key challenge for flexible hybrid electronics. Currently, a multisubstrate approach is employed, where soft and hard devices are fabricated or assembled on separate substrates, and bonded or interfaced using connectors; this hinders the flexibility of the device and is prone to interconnect issues. Here, a single substrate interfacing approach is reported, where soft devices, i.e., sensors, are directly printed on Kapton polyimide substrates that are widely used for fabricating flexible printed circuit boards (FPCBs). Utilizing a process flow compatible with the FPCB assembly process, a wearable sensor patch is fabricated composed of inkjet‐printed gold electrocardiography (ECG) electrodes and a stencil‐printed nickel oxide thermistor. The ECG electrodes provide 1 mVp–p ECG signal at 4.7 cm electrode spacing and the thermistor is highly sensitive at normal body temperatures, and demonstrates temperature coefficient, α ≈ –5.84% K^–1 and material constant, β ≈ 4330 K. This sensor platform can be extended to a more sophisticated multisensor platform where sensors fabricated using solution processable functional inks can be interfaced to hard electronics for health and performance monitoring, as well as internet of things applications.     

Body Heat Powered Wirelessly Wearable System for Real-time Physiological and Biochemical Monitoring

Through harvesting energy from the environment or human body, self-power wearable electronics have an opportunity to break through the limitations of battery supply and achieving long-term continuous operation. Here, a wireless wearable monitoring system driven entirely by body heat is implemented. Based on the principle of maximizing heat utilization, while optimizing internal resistance and heat dissipation, the stretchable TEG improves the power density of previous similar devices from only a few microwatts per square centimeter to tens and makes it possible to continuously drive wireless wearable electronic systems. Furthermore, ceaseless self-power energy gives wearable electronics unparalleled continuous working ability, which can realize the tracking and monitoring of biochemical and physiological indicators at different time scale. A practical system demonstrates the ability to real-time monitor heart rate, sweat ingredient and body motion at a high sampling rate. This study marks an important advance of self-powered wearable electronics for wirelessly real-time healthy monitoring.     

Emerging Wearable Sensors for Plant Health Monitoring

Emerging plant diseases, caused by pathogens, pests, and climate change, are critical threats to not only the natural ecosystem but also human life. To mitigate crop loss due to various biotic and abiotic stresses, new sensor technologies to monitor plant health, predict, and track plant diseases in real time are desired. Wearable electronics have recently been developed for human health monitoring. However, the application of wearable electronics to agriculture and plant science is in its infancy. Wearable technologies mean that the sensors will be directly placed on the surfaces of plant organs such as leaves and stems. The sensors are designed to detect the status of plant health by profiling various trait biomarkers and microenvironmental parameters, transducing bio-signals to electric readout for data analytics. In this perspective, the recent progress in wearable plant sensors is summarized and they are categorized by the functionality, namely plant growth sensors, physiology, and microclimate sensors, chemical sensors, and multifunctional sensors. The design and mechanism of each type of wearable sensors are discussed and their applications to address the current challenges of precision agriculture are highlighted. Finally, challenges and perspectives for the future development of wearable plant sensors are presented.     

Flexible Wearable Pre-fractal Antennas for Personal High-Temperature Monitoring

Wireless Personal Communications - This paper proposed a new flexible and wearable antennas design based on teragon pre-fractal geometry until the third level, for monitoring high-temperature in...     

A Self-powered Wearable Wireless Sensor System Powered by a Hybrid Energy Harvester for Healthcare Applications

Wireless Personal Communications - In this paper, a wearable medical sensor system is designed for long-term healthcare applications. This system is used for monitoring temperature, heartbeat,...     

A Conceptual Design of Model Coil for the 40-T Hybrid Magnet Superconducting Outsert

The High Magnetic Field Laboratory of the Chinese Academy of Sciences will develop a 40-T hybrid magnet. The superconducting outsert, which consists of a NbTi coil and a $hbox{Nb}_{3} hbox{Sn}$ coil, will provide more than 11 T of central field in a 580-mm bore. The superconducting coils will be wound of cable-in-conduit conductor (CICC) and cooled by flowing 4.5-K supercritical helium. A model coil of the $hbox{Nb}_{3}hbox{Sn}$ coil has been designed and will be manufactured to develop the technology of cabling, jacketing, winding, heat treatment, etc., and the model coil can also simulate the performance of the $hbox{Nb}_{3}hbox{Sn}$ superconducting coil under its operating conditions. This paper gives an overview of the conceptual design for the model coil and predicts its current-sharing temperature (Tcs).      

Stretchable Composite Acoustic Transducer for Wearable Monitoring of Vital Signs

A highly flexible, stretchable, and mechanically robust low‐cost soft composite consisting of silicone polymers and water (or hydrogels) is reported. When combined with conventional acoustic transducers, the materials reported enable high performance real‐time monitoring of heart and respiratory patterns over layers of clothing (or furry skin of animals) without the need for direct contact with the skin. The approach enables an entirely new method of fabrication that involves encapsulation of water and hydrogels with silicones and exploits the ability of sound waves to travel through the body. The system proposed outperforms commercial, metal‐based stethoscopes for the auscultation of the heart when worn over clothing and is less susceptible to motion artefacts. The system both with human and furry animal subjects (i.e., dogs), primarily focusing on monitoring the heart, is tested; however, initial results on monitoring breathing are also presented. This work is especially important because it is the first demonstration of a stretchable sensor that is suitable for use with furry animals and does not require shaving of the animal for data acquisition.     

可穿戴心电信号监测中运动伪影消除技术研究

心电图(ECG)是心脏疾病诊断最有效的工具。噪声的去除和Q波、R波、S波的提取是心电信号检测中的两大主题。本文使用Savitzky-Golay滤波器对人体在弯腰、走路、坐下-站起等运动状态下采集的心电信号进行分析,去除信号中的基线漂移和运动伪影,并对滤波后信号的Q波、R波和S波进行检测。通过将本文提出的滤波方式与卡尔曼滤波、小波分解就时间复杂度和功率谱密度两个参数进行对比分析,评估Savitzky-Golay滤波器在心电信号中运动伪影去除的优势。实验结果表明,Savitzky-Golay滤波器能更加有效地适应心电信号的变化,有效地去除心电信号中的噪声,并且最大限度保持心电波形的形状和波峰。      

Muscle Fibers Inspired High-Performance Piezoelectric Textiles for Wearable Physiological Monitoring

The next-generation wearable biosensors with highly biocompatible, stretchable, and robust features are expected to enable the change of the current reactive and disease-centric healthcare system to a personalized model with a focus on disease prevention and health promotion. Herein, a muscle-fiber-inspired nonwoven piezoelectric textile with tunable mechanical properties for wearable physiological monitoring is developed. To mimic the muscle fibers, polydopamine (PDA) is dispersed into the electrospun barium titanate/polyvinylidene fluoride (BTO/PVDF) nanofibers to enhance the interfacial-adhesion, mechanical strength, and piezoelectric properties. Such improvements are both experimentally observed via mechanical characterization and theoretically verified by the phase-field simulation. Taking the PDA@BTO/PVDF nanofibers as the building blocks, a nonwoven light-weight piezoelectric textile is fabricated, which hold an outstanding sensitivity (3.95 V N⁻¹) and long-term stability (<3% decline after 7,400 cycles). The piezoelectric textile demonstrates multiple potential applications, including pulse wave measurement, human motion monitoring, and active voice recognition. By creatively mimicking the muscle fibers, this work paves a cost-effective way to develop high-performance and self-powered wearable bioelectronics for personalized healthcare.     

HFC反向通道噪声监测和抑制系统

设计了一种HFC反向通道噪声监测和噪声抑制系统,采用S3C4510B ARM芯片构架以太网应用系统,采用TMS320C6713B DSP芯片对采集的大容量数据进行实时频谱分析,利用FPGA芯片实现高速数据缓存和系统的逻辑控制.试验表明该系统能对HFC反向通道的信号进行实时采集和高速处理,可有效地对HFC反向通道进行维护.     

Wearable and Highly Sensitive Graphene Strain Sensors for Human Motion Monitoring

Sensing strain of soft materials in small scale has attracted increasing attention. In this work, graphene woven fabrics (GWFs) are explored for highly sensitive sensing. A flexible and wearable strain sensor is assembled by adhering the GWFs on polymer and medical tape composite film. The sensor exhibits the following features: ultra‐light, relatively good sensitivity, high reversibility, superior physical robustness, easy fabrication, ease to follow human skin deformation, and so on. Some weak human motions are chosen to test the notable resistance change, including hand clenching, phonation, expression change, blink, breath, and pulse. Because of the distinctive features of high sensitivity and reversible extensibility, the GWFs based piezoresistive sensors have wide potential applications in fields of the displays, robotics, fatigue detection, body monitoring, and so forth.     

A Survey on Wearable Sensor-Based Systems for Health Monitoring and Prognosis

The design and development of wearable biosensor systems for health monitoring has garnered lots of attention in the scientific community and the industry during the last years. Mainly motivated by increasing healthcare costs and propelled by recent technological advances in miniature biosensing devices, smart textiles, microelectronics, and wireless communications, the continuous advance of wearable sensor-based systems will potentially transform the future of healthcare by enabling proactive personal health management and ubiquitous monitoring of a patient's health condition. These systems can comprise various types of small physiological sensors, transmission modules and processing capabilities, and can thus facilitate low-cost wearable unobtrusive solutions for continuous all-day and any-place health, mental and activity status monitoring. This paper attempts to comprehensively review the current research and development on wearable biosensor systems for health monitoring. A variety of system implementations are compared in an approach to identify the technological shortcomings of the current state-of-the-art in wearable biosensor solutions. An emphasis is given to multiparameter physiological sensing system designs, providing reliable vital signs measurements and incorporating real-time decision support for early detection of symptoms or context awareness. In order to evaluate the maturity level of the top current achievements in wearable health-monitoring systems, a set of significant features, that best describe the functionality and the characteristics of the systems, has been selected to derive a thorough study. The aim of this survey is not to criticize, but to serve as a reference for researchers and developers in this scientific area and to provide direction for future research improvements.      

混合超宽带多微微网干扰模型及性能改善

蓝牙和超宽带核心技术的结合,将会进一步推进无线高数据速率网络的发展.在这篇论文中,提出一种新型的微微网系统模型,即实现蓝牙拓扑和MB-OFDM超宽带技术的结合,考虑路径损失的影响和使用TFC编码来模拟所提出方案的相邻微微网间干扰.用BER 比 Eb/N0曲线图来评估所提出的干扰模型.最后,提出一个6频带的方案来改善所构造的混合系统的性能.仿真结果表明,文中所提出的模拟结构胜过以往传统的模型.     

语义搜索引擎概念模型

语义搜索引擎作为未来的万维网搜索引擎，将不仅仅基于关键词检索，而是能够理解Web页面的内容，并进行逻辑推理来完成复杂的查询任务，最终返回精确的结果。对语义Web和搜索引擎技术进行了简要介绍，提出一种语义搜索引擎概念模型，并对其构成模块及模块问的互操作进行了描述，最后对概念模型具体实现上的关键技术进行了简要说明。     

A Robust Wearable Point-of-Care CNT-Based Strain Sensor for Wirelessly Monitoring Throat-Related Illnesses

Point-of-care testing (POC) has the ability to detect chronic and infectious diseases early or at the time of occurrence and provide a state-of-the-art personalized healthcare system. Recently, wearable and flexible sensors have been employed to analyze sweat, glucose, blood, and human skin conditions. However, a flexible sensing system that allows for the real-time monitoring of throat-related illnesses, such as salivary parotid gland swelling caused by flu and mumps, is necessary. Here, for the first time, a wearable, highly flexible, and stretchable piezoresistive sensing patch based on carbon nanotubes (CNTs) is reported, which can record muscle expansion or relaxation in real-time, and thus act as a next-generation POC sensor. The patch offers an excellent gauge factor for in-plane stretching and spatial expansion with low hysteresis. The actual extent of muscle expansion is calculated and the gauge factor for applications entailing volumetric deformations is redefined. Additionally, a bluetooth-low-energy system that tracks muscle activity in real-time and transmits the output signals wirelessly to a smartphone app is utilized. Numerical calculations verify that the low stress and strain lead to excellent mechanical reliability and repeatability. Finally, a dummy muscle is inflated using a pneumatic-based actuator to demonstrate the application of the affixed wearable next-generation POC sensor.     

Hybrid Smart Fiber with Spontaneous Self‐Charging Mechanism for Sustainable Wearable Electronics

Smart wearable electronics that are fabricated on light‐weight fabrics or flexible substrates are considered to be of next‐generation and portable electronic device systems. Ideal wearable and portable applications not only require the device to be integrated into various fiber form factors, but also desire self‐powered system in such a way that the devices can be continuously supplied with power as well as simultaneously save the acquired energy for their portability and sustainability. Nevertheless, most of all self‐powered wearable electronics requiring both the generation of the electricity and storing of the harvested energy, which have been developed so far, have employed externally connected individual energy generation and storage fiber devices using external circuits. In this work, for the first time, a hybrid smart fiber that exhibits a spontaneous energy generation and storage process within a single fiber device that does not need any external electric circuit/connection is introduced. This is achieved through the employment of asymmetry coaxial structure in an electrolyte system of the supercapacitor that creates potential difference upon the creation of the triboelectric charges. This development in the self‐charging technology provides great opportunities to establish a new device platform in fiber/textile‐based electronics.