Remote ECG monitoring systems are becoming commonplace medical devices for remote heart monitoring. In recent years, remote ECG monitoring systems have been applied in the monitoring of various kinds of heart diseases...Remote ECG monitoring systems are becoming commonplace medical devices for remote heart monitoring. In recent years, remote ECG monitoring systems have been applied in the monitoring of various kinds of heart diseases, and the quality of the transmission and re- ception of the ECG signals during remote process kept advancing. However, there remains accompanying challenges. This report focuses on the three components of the remote ECG monitoring system: patient (the end user), the doctor workstation, and the remote server, reviewing and evaluating the imminent challenges on the wearable systems, packet loss in remote transmission, portable ECG monitoring system, pa- tient ECG data collection system, and ECG signals transmission including real-time processing ST segment, R wave, RR interval and QRS wave, etc. This paper tries to clarify the future developmental strategies of the ECG remote monitoring, which can be helpful in guiding the research and development of remote ECG monitoring.展开更多
The installation of vast quantities of additional new sensing and communication equipment, in conjunction with building the computing infrastructure to store and manage data gathered by this equipment, has been the fi...The installation of vast quantities of additional new sensing and communication equipment, in conjunction with building the computing infrastructure to store and manage data gathered by this equipment, has been the fi rst step in the creation of what is generically referred to as the "smart grid" for the electric transmission system. With this enormous capital investment in equipment having been made, attention is now focused on developing methods to analyze and visualize this large data set. The most direct use of this large set of new data will be in data visualization. This paper presents a survey of some visualization techniques that have been deployed by the electric power industry for visualizing data over the past several years. These techniques include pie charts, animation, contouring, time-varying graphs, geographic-based displays, image blending, and data aggregation techniques. The paper then emphasizes a newer concept of using word-sized graphics called sparklines as an extremely eff ective method of showing large amounts of timevarying data.展开更多
This study focuses on a development of heat transfer enhancement techniques using pulsating flow for thermal equipment such as electronic equipment and heat exchangers. In this report, the heat transfer performance of...This study focuses on a development of heat transfer enhancement techniques using pulsating flow for thermal equipment such as electronic equipment and heat exchangers. In this report, the heat transfer performance of the pulsating airflow around the heating pillar mounted in the rectangular enclosure was investigated experimentally while changing the size of the clearance between the enclosure wall and the pillar. The pillar simulates the components mounted in thermal equipment such as fins and electrical components. The rectangular enclosure simulates an enclosure of electronic equipment and heat exchangers. The shape of the cross section of the pillar was square having sides 30 mm. The dimension of the width of the enclosure was changed from 50 mm to 80 mm. It was found that the heat transfer performance of the pulsating airflow became higher than that of the steady flow regardless of the dimension of the clearance. The heat transfer enhancement around heating components by the pulsating flow can be available regardless of the clearance around the components.展开更多
Induction motor is used in many applications to drive an electromechanical system. Transients of the motor torque and speed are outlined by the inertia of rotating rotor. The paper deals with influence of rotor inerti...Induction motor is used in many applications to drive an electromechanical system. Transients of the motor torque and speed are outlined by the inertia of rotating rotor. The paper deals with influence of rotor inertia to transients of motor speed. The method of speed control measurement and experimental equipment is discussed. Simulation and experimental results are compared.展开更多
A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to fur...A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to further diagnose and locate the potential problem of the cable system. This paper presents the experience of the present authors carrying out the cable test. Following a brief introduction to the experiment equipments and physical connections, the paper analyses the data collected from the testing, including PD pulse shape analysis, frequency spectrum analysis and phase resolved PD pattern analysis. Associated with PD propagation direction identification, PD source diagnosis and localisation was made. Four different types of sensors, which were adapted during the testing, are shown to have different frequency bandwidths and performed differently. Aider comparing the parameters of the sensor and the PD signals detected by individual sensor, optimal PD monitoring bandwidth for cable system is suggested.展开更多
Inline characterization for fabrication of silicon wafer PV (photovoltaic) devices may be used to optimize device efficiencies, reduce their performance variance, and their cost of production. In this article, the f...Inline characterization for fabrication of silicon wafer PV (photovoltaic) devices may be used to optimize device efficiencies, reduce their performance variance, and their cost of production. In this article, the frozen in strain from a variety of extended defects in silicon is shown to effect the polarization of light transmitted through a silicon substrate due to the photo-elastic effect. Transmission polarimetry on pre-fabricated silicon substrates may be used for identification of extended defects in the materials using a polarization analysis instrument. Instrumentation is proposed for detection of defects in raw silicon wafers for applications like raw silicon wafer sorting, scanning silicon bricks, and inline inspection prior to solar cell metallization. Such analysis may assist with gettering of silicon solar cells, may be implemented in the sorting and rejection procedures in PV device fabrication, and in general shows advantages for detection of defects in silicon wafer solar cell materials and devices.展开更多
The electrical transmission networks are complex systems that are commonly run near their operational limits. Such systems can undergo major disturbances that have serious consequences. Individually, these disturbance...The electrical transmission networks are complex systems that are commonly run near their operational limits. Such systems can undergo major disturbances that have serious consequences. Individually, these disturbances can be attributed to specific causes, such as lightning strikes, ice storms, equipment failure, shorts resulting from untrimmed trees, excessive customer demand, or human errors. In the paper, the human errors from electrical transmission networks of Romanian Power Grid Company over period of 10 years are analyzed. It is hoped that obtained results will provide engineers a better understanding so they can cater to the needs of the human operators when to implement new interfaces for network monitoring tasks, not for the other technical objectives.展开更多
There has been ongoing keen interest to mold electronic devices into desired shapes and be laid on desired configurable surfaces. In specific, the ability to design materials that can bend, twist, compress and stretch...There has been ongoing keen interest to mold electronic devices into desired shapes and be laid on desired configurable surfaces. In specific, the ability to design materials that can bend, twist, compress and stretch repeatedly, while still able to maintain its full capability as conductors or electrodes, has led to numerous efforts to develop flexible and stretchable (bio)devices that are both technologically challenging and environmentally friendly (e.g. biodegradable). In this review, we highlight several recent significant results that have made impacts toward the field of flexible and stretchable electronics, sensors and power sources.展开更多
When operating an equipment or a power system at the high voltage, problems associated with partial discharge (PD) can be tracked down to electromagnetic emission, acoustic emission or chemical reactions such as the...When operating an equipment or a power system at the high voltage, problems associated with partial discharge (PD) can be tracked down to electromagnetic emission, acoustic emission or chemical reactions such as the formation of ozone and nitrous oxide gases. The high voltage equipment and high voltage installation owners have come to terms with the need for conditions monitoring the^process of PD in the equipments such as power transformers, gas insulated substations (GIS), and cable installations. This paper reviews the available PD detection methods (involving high voltage equipment) such as electrical detection, chemical detection, acoustic detection, and optical detection. Advantages and disadvantages of each method have been explored and compared. The review suggests that optical detection techniques provide many advantages in the consideration of accuracy and suitability for the applications when compared to other techniques.展开更多
Smart flexible electronics with underwater motion detection have become a promising research aspect in intelligent perception.Inspired by the strong adaptability of marine creatures to complex underwater environments,...Smart flexible electronics with underwater motion detection have become a promising research aspect in intelligent perception.Inspired by the strong adaptability of marine creatures to complex underwater environments,conventional biocompatible hydrogels are worth developing into organogels with preferred underwater adhesive properties,hydrophobic and antiswelling performance,and motion perception ability.Herein,a highly sensitive organogel sensor exhibiting good hydrophobicity,electromechanical properties,and adhesion properties was prepared for underwater utilization by regulating the chemical components and internal interactions.The synergistic effect of massive reversible noncovalent bonds ensures the organogel’s excellent underwater adhesion to multifarious substrates.Meanwhile,the interactions of hydrophobic conductive fillers and the dynamic hydrophobic associations in the organogel endow it with satisfactory hydrophobic performance(contact angle of111.8°)and antiswelling property(equilibrium swelling ratio of-31%after 15-day immersion).The fabricated flexible organogel strain sensor exhibits high sensitivity(gauge factor of1.96),ultrafast response rate(79.1 ms),low limit of detection(0.45 Pa),and excellent cyclic stability(1044 tensile cycles followed by 3981 compressive cycles).Results demonstrate the proposed organogel’s precise perception of sophisticated human motions in air and underwater,which expands its application scenarios.展开更多
A similarity equation for heat transfer on heat source elements situated in the entrance region in electronic equipment is developed based on the experimental data obtained by Sparrow et al.[4]. The characteristic of ...A similarity equation for heat transfer on heat source elements situated in the entrance region in electronic equipment is developed based on the experimental data obtained by Sparrow et al.[4]. The characteristic of the similarity equation is that the ratio of the heat transfer coefficient at the entrance region to be at the fully developed region is independent of the Reynolds number. It depends only on the row number of the elements situated in the entrance region. An example of the usefulness of the similarity equation is presented that determines the heat transfer on heat source elements in a power unit that contains only a small number of the heat source elements.展开更多
In recent years, triboelectric nanogenerators have attracted much attention because of their unique potential in self-powered nanosensors and nanosystems. In this paper, we report a cylindrical spiral tdboelectric nan...In recent years, triboelectric nanogenerators have attracted much attention because of their unique potential in self-powered nanosensors and nanosystems. In this paper, we report a cylindrical spiral tdboelectric nanogenerator (S-TENG), which not only can produce high electric output to power display devices, but also can be used as a self-powered displacement sensor integrated on a measurement ruler. At a sliding speed of 2.5 m/s, S-TENG can generate a short-circuit current (Isc) of 30 μA and an open-circuit voltage (Voc) of 40 V. As the power source, we fabricate a transparent and flexible hand-driven S-TENG. Furthermore, we demonstrate a self-powered S-TENG-based measuring tapeline that can accurately measure and display the pulled-out distance without the need for an extra battery. The results obtained indicate that TENG-based devices have good potential for application in self-powered measurement systems.展开更多
Persuasive technology is the use of computers,devices or applications to change a person's attitudes or behavior.Persuasibility design within the system life-cycle is a nascent area of research which is different ...Persuasive technology is the use of computers,devices or applications to change a person's attitudes or behavior.Persuasibility design within the system life-cycle is a nascent area of research which is different from design in the traditional method.This paper focuses on the research of persuasibility design and its assessment in the system life-cycle.A life-cycle oriented systemic general theory is developed in this paper to evaluate persuasibility design.Persuasibility assessment is considered as a part of persuasibility design.Its procedure and method are explored and analyzed based on the system life-cycle in this paper.A possible research direction is to create more explicit and detailed persuasion design and assessment methods which can be used not only in personal computer persuasive application,but also many other electric devices that are designed for persuasion purposes.展开更多
Optic-electric responsive materials have attracted much attention for their applications in temperaturesensing,actuators,and memory switches.However,it is a challenge to integrate various functions to form multifuncti...Optic-electric responsive materials have attracted much attention for their applications in temperaturesensing,actuators,and memory switches.However,it is a challenge to integrate various functions to form multifunctional responsive materials.As molecule-based hybrid materials usually consist of organic and inorganic components,the introduction of multiple functions can be achieved through structural construction.Thus far,even though fulltemperature cover is required for device applications,fulltemperature covered multi-switchable hybrid materials have rarely been successfully synthesized.Herein,the dynamic[(CH3)3NOH]+cation and luminous center Mn(II)were introduced to form a hybrid material[(CH3)3NOH][Mn Cl3],showing multiple temperature-responsive behaviors.Upon temperature change,it exhibits multi-state dielectric switching response and intensity or peak shift response of luminous in full-temperature range(low,room,and high temperatures).These responsive behaviors are triggered by the motion or reorientation of[(CH3)3NOH]+cations and inorganic framework.Overall,the switchable photoelectric material has potential applications in multiple encrypted storage and sensor devices.展开更多
Conventional rigid electronics are usually unconformable with soft skins and tend to fail in accurate physiological monitoring and precise treatment. Electronic skins(e-Skins) made by conductive and stretchable materi...Conventional rigid electronics are usually unconformable with soft skins and tend to fail in accurate physiological monitoring and precise treatment. Electronic skins(e-Skins) made by conductive and stretchable materials offer mechanical compliance for fabricating flexible and conformable wearables. Compared to common organic or inorganic conductive materials, gallium-based liquid metals alone own superior conductivity and compliance. Here, we demonstrate a highly conductive and stretchable electronic skin with liquid metal circuits(LMCs) embedded in silicone rubber film, which are functionalized for physiological signals monitoring. Through the designs of serpentine structure, LMCs maintained good electrical conductivity and functionality under over 100% strain. Also, a wearable electrocardiogram(ECG) recording device was fabricated and tested. The device was able to acquire steady signals during real-time measurement of physical activities. The proposed liquid metal e-Skin can be further extended to conformable bio-integrated healthcare devices and intelligent health monitoring networks.展开更多
文摘Remote ECG monitoring systems are becoming commonplace medical devices for remote heart monitoring. In recent years, remote ECG monitoring systems have been applied in the monitoring of various kinds of heart diseases, and the quality of the transmission and re- ception of the ECG signals during remote process kept advancing. However, there remains accompanying challenges. This report focuses on the three components of the remote ECG monitoring system: patient (the end user), the doctor workstation, and the remote server, reviewing and evaluating the imminent challenges on the wearable systems, packet loss in remote transmission, portable ECG monitoring system, pa- tient ECG data collection system, and ECG signals transmission including real-time processing ST segment, R wave, RR interval and QRS wave, etc. This paper tries to clarify the future developmental strategies of the ECG remote monitoring, which can be helpful in guiding the research and development of remote ECG monitoring.
基金the Power Systems Engineering Research Foundation (PSERC)the US National Science Foundation (1128325)
文摘The installation of vast quantities of additional new sensing and communication equipment, in conjunction with building the computing infrastructure to store and manage data gathered by this equipment, has been the fi rst step in the creation of what is generically referred to as the "smart grid" for the electric transmission system. With this enormous capital investment in equipment having been made, attention is now focused on developing methods to analyze and visualize this large data set. The most direct use of this large set of new data will be in data visualization. This paper presents a survey of some visualization techniques that have been deployed by the electric power industry for visualizing data over the past several years. These techniques include pie charts, animation, contouring, time-varying graphs, geographic-based displays, image blending, and data aggregation techniques. The paper then emphasizes a newer concept of using word-sized graphics called sparklines as an extremely eff ective method of showing large amounts of timevarying data.
文摘This study focuses on a development of heat transfer enhancement techniques using pulsating flow for thermal equipment such as electronic equipment and heat exchangers. In this report, the heat transfer performance of the pulsating airflow around the heating pillar mounted in the rectangular enclosure was investigated experimentally while changing the size of the clearance between the enclosure wall and the pillar. The pillar simulates the components mounted in thermal equipment such as fins and electrical components. The rectangular enclosure simulates an enclosure of electronic equipment and heat exchangers. The shape of the cross section of the pillar was square having sides 30 mm. The dimension of the width of the enclosure was changed from 50 mm to 80 mm. It was found that the heat transfer performance of the pulsating airflow became higher than that of the steady flow regardless of the dimension of the clearance. The heat transfer enhancement around heating components by the pulsating flow can be available regardless of the clearance around the components.
文摘Induction motor is used in many applications to drive an electromechanical system. Transients of the motor torque and speed are outlined by the inertia of rotating rotor. The paper deals with influence of rotor inertia to transients of motor speed. The method of speed control measurement and experimental equipment is discussed. Simulation and experimental results are compared.
文摘A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to further diagnose and locate the potential problem of the cable system. This paper presents the experience of the present authors carrying out the cable test. Following a brief introduction to the experiment equipments and physical connections, the paper analyses the data collected from the testing, including PD pulse shape analysis, frequency spectrum analysis and phase resolved PD pattern analysis. Associated with PD propagation direction identification, PD source diagnosis and localisation was made. Four different types of sensors, which were adapted during the testing, are shown to have different frequency bandwidths and performed differently. Aider comparing the parameters of the sensor and the PD signals detected by individual sensor, optimal PD monitoring bandwidth for cable system is suggested.
文摘Inline characterization for fabrication of silicon wafer PV (photovoltaic) devices may be used to optimize device efficiencies, reduce their performance variance, and their cost of production. In this article, the frozen in strain from a variety of extended defects in silicon is shown to effect the polarization of light transmitted through a silicon substrate due to the photo-elastic effect. Transmission polarimetry on pre-fabricated silicon substrates may be used for identification of extended defects in the materials using a polarization analysis instrument. Instrumentation is proposed for detection of defects in raw silicon wafers for applications like raw silicon wafer sorting, scanning silicon bricks, and inline inspection prior to solar cell metallization. Such analysis may assist with gettering of silicon solar cells, may be implemented in the sorting and rejection procedures in PV device fabrication, and in general shows advantages for detection of defects in silicon wafer solar cell materials and devices.
文摘The electrical transmission networks are complex systems that are commonly run near their operational limits. Such systems can undergo major disturbances that have serious consequences. Individually, these disturbances can be attributed to specific causes, such as lightning strikes, ice storms, equipment failure, shorts resulting from untrimmed trees, excessive customer demand, or human errors. In the paper, the human errors from electrical transmission networks of Romanian Power Grid Company over period of 10 years are analyzed. It is hoped that obtained results will provide engineers a better understanding so they can cater to the needs of the human operators when to implement new interfaces for network monitoring tasks, not for the other technical objectives.
基金funding from the Bill and Melinda Gates Foundation Grand Challenge Award (OPP1032970)
文摘There has been ongoing keen interest to mold electronic devices into desired shapes and be laid on desired configurable surfaces. In specific, the ability to design materials that can bend, twist, compress and stretch repeatedly, while still able to maintain its full capability as conductors or electrodes, has led to numerous efforts to develop flexible and stretchable (bio)devices that are both technologically challenging and environmentally friendly (e.g. biodegradable). In this review, we highlight several recent significant results that have made impacts toward the field of flexible and stretchable electronics, sensors and power sources.
文摘When operating an equipment or a power system at the high voltage, problems associated with partial discharge (PD) can be tracked down to electromagnetic emission, acoustic emission or chemical reactions such as the formation of ozone and nitrous oxide gases. The high voltage equipment and high voltage installation owners have come to terms with the need for conditions monitoring the^process of PD in the equipments such as power transformers, gas insulated substations (GIS), and cable installations. This paper reviews the available PD detection methods (involving high voltage equipment) such as electrical detection, chemical detection, acoustic detection, and optical detection. Advantages and disadvantages of each method have been explored and compared. The review suggests that optical detection techniques provide many advantages in the consideration of accuracy and suitability for the applications when compared to other techniques.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20190688)the Natural Science Foundation of Jiangsu Higher Education Institutions(21KJB430039)Taishan Scholar Construction Special Fund of Shandong Province。
文摘Smart flexible electronics with underwater motion detection have become a promising research aspect in intelligent perception.Inspired by the strong adaptability of marine creatures to complex underwater environments,conventional biocompatible hydrogels are worth developing into organogels with preferred underwater adhesive properties,hydrophobic and antiswelling performance,and motion perception ability.Herein,a highly sensitive organogel sensor exhibiting good hydrophobicity,electromechanical properties,and adhesion properties was prepared for underwater utilization by regulating the chemical components and internal interactions.The synergistic effect of massive reversible noncovalent bonds ensures the organogel’s excellent underwater adhesion to multifarious substrates.Meanwhile,the interactions of hydrophobic conductive fillers and the dynamic hydrophobic associations in the organogel endow it with satisfactory hydrophobic performance(contact angle of111.8°)and antiswelling property(equilibrium swelling ratio of-31%after 15-day immersion).The fabricated flexible organogel strain sensor exhibits high sensitivity(gauge factor of1.96),ultrafast response rate(79.1 ms),low limit of detection(0.45 Pa),and excellent cyclic stability(1044 tensile cycles followed by 3981 compressive cycles).Results demonstrate the proposed organogel’s precise perception of sophisticated human motions in air and underwater,which expands its application scenarios.
文摘A similarity equation for heat transfer on heat source elements situated in the entrance region in electronic equipment is developed based on the experimental data obtained by Sparrow et al.[4]. The characteristic of the similarity equation is that the ratio of the heat transfer coefficient at the entrance region to be at the fully developed region is independent of the Reynolds number. It depends only on the row number of the elements situated in the entrance region. An example of the usefulness of the similarity equation is presented that determines the heat transfer on heat source elements in a power unit that contains only a small number of the heat source elements.
基金Acknowledgements Thanks for the support from the "thousands talents" program for pioneer researcher and his innovation team, China, National Natural Science Foundation of China (Nos. 51432005 and 61405131), Beijing Natural Science Foundation (No. 4154090), Beijing City Committee of science and technology (Nos. Z131100006013004 and Z131100006013005).
文摘In recent years, triboelectric nanogenerators have attracted much attention because of their unique potential in self-powered nanosensors and nanosystems. In this paper, we report a cylindrical spiral tdboelectric nanogenerator (S-TENG), which not only can produce high electric output to power display devices, but also can be used as a self-powered displacement sensor integrated on a measurement ruler. At a sliding speed of 2.5 m/s, S-TENG can generate a short-circuit current (Isc) of 30 μA and an open-circuit voltage (Voc) of 40 V. As the power source, we fabricate a transparent and flexible hand-driven S-TENG. Furthermore, we demonstrate a self-powered S-TENG-based measuring tapeline that can accurately measure and display the pulled-out distance without the need for an extra battery. The results obtained indicate that TENG-based devices have good potential for application in self-powered measurement systems.
文摘Persuasive technology is the use of computers,devices or applications to change a person's attitudes or behavior.Persuasibility design within the system life-cycle is a nascent area of research which is different from design in the traditional method.This paper focuses on the research of persuasibility design and its assessment in the system life-cycle.A life-cycle oriented systemic general theory is developed in this paper to evaluate persuasibility design.Persuasibility assessment is considered as a part of persuasibility design.Its procedure and method are explored and analyzed based on the system life-cycle in this paper.A possible research direction is to create more explicit and detailed persuasion design and assessment methods which can be used not only in personal computer persuasive application,but also many other electric devices that are designed for persuasion purposes.
基金financially supported by the National Natural Science Foundation of China(21991141)the Natural Science Foundation of Zhejiang Province(LZ20B010001)Zhejiang Normal University。
文摘Optic-electric responsive materials have attracted much attention for their applications in temperaturesensing,actuators,and memory switches.However,it is a challenge to integrate various functions to form multifunctional responsive materials.As molecule-based hybrid materials usually consist of organic and inorganic components,the introduction of multiple functions can be achieved through structural construction.Thus far,even though fulltemperature cover is required for device applications,fulltemperature covered multi-switchable hybrid materials have rarely been successfully synthesized.Herein,the dynamic[(CH3)3NOH]+cation and luminous center Mn(II)were introduced to form a hybrid material[(CH3)3NOH][Mn Cl3],showing multiple temperature-responsive behaviors.Upon temperature change,it exhibits multi-state dielectric switching response and intensity or peak shift response of luminous in full-temperature range(low,room,and high temperatures).These responsive behaviors are triggered by the motion or reorientation of[(CH3)3NOH]+cations and inorganic framework.Overall,the switchable photoelectric material has potential applications in multiple encrypted storage and sensor devices.
基金supported by the National Natural Science Foundation of China(Grant No.91748206)Funding of Higher Education AgencyFrontier Funding of Chinese Academy of Sciences
文摘Conventional rigid electronics are usually unconformable with soft skins and tend to fail in accurate physiological monitoring and precise treatment. Electronic skins(e-Skins) made by conductive and stretchable materials offer mechanical compliance for fabricating flexible and conformable wearables. Compared to common organic or inorganic conductive materials, gallium-based liquid metals alone own superior conductivity and compliance. Here, we demonstrate a highly conductive and stretchable electronic skin with liquid metal circuits(LMCs) embedded in silicone rubber film, which are functionalized for physiological signals monitoring. Through the designs of serpentine structure, LMCs maintained good electrical conductivity and functionality under over 100% strain. Also, a wearable electrocardiogram(ECG) recording device was fabricated and tested. The device was able to acquire steady signals during real-time measurement of physical activities. The proposed liquid metal e-Skin can be further extended to conformable bio-integrated healthcare devices and intelligent health monitoring networks.