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A NOVEL BITTER DETECTION BIOSENSOR BASED ON LIGHT ADDRESSABLE POTENTIOMETRIC SENSOR 被引量:1
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作者 CHUNSHENG WU LIPING DU +1 位作者 LIHUI MAO PING WANG 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2012年第2期34-40,共7页
This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor(LAPS).Taste receptor cells(TRCs)were used as sensitive elements,which can respond to differe... This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor(LAPS).Taste receptor cells(TRCs)were used as sensitive elements,which can respond to different bitter stimuli with extreme high sensitivity and speci-ficity.TRCs were isolated from the taste buds of rats and cultured on the surface of LAPS chip.Due to the unique advantages such as single-cell recording,light addressable capability,and noninvasiveness,LAPS chip was used as secondary transducer to monitor the responses of TRCs by recording extracelluar potential changes.The results indicate LAPS chip can effectively record the responses of TRCs to different bitter substances used in this study in a real-time manner for a long-term.In addition,by performing principal component analysis on the LAPS recording data,different bitter substances tested can be successfully discriminated.It is suggested this TRCsLAPS hybrid biosensor could be a valuable tool for bitter substance detection.With further improvement and novel design,it has great potentials to be applied in both basic research and practical applications related to bitter taste detection. 展开更多
关键词 Taste receptor cells bitter detection bitter signal transduction light addressable potentiometric sensor BIOsensor
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Design of Energy Saving Lighting System in University Classroom Based on Wireless Sensor Network
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作者 Yu Liang Ruihua Zhang +1 位作者 Wei Wang Caiqing Xiao 《Communications and Network》 2013年第1期55-60,共6页
In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, includin... In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, including design of sensor node and sink, as well as corresponding development of control program and upper-computer software. The system sets single-chip Ameg16 as control center, realizes communication between nodes via nRF24L01 wireless transceiver module, and realizes communication between sink and upper computer via w5100 wireless internet module. It perceives illumination intensity via photoconductor, detects the human body position via infrared pyroelectric sensor, and places the sensor node on the lamp, so the light can be controlled according to position of human body and current illumination intensity, which can realize energy saving to a large extent on condition that lighting requirement is satisfied. The system has low cost, and there is no need to change the original lighting circuit. The light can be turned off by hand, and when multi-media are used for the class, light can keep off even it is dim. In addition, this system has the function of automatic fault report, which is convenient for property maintenance. 展开更多
关键词 Wireless sensor Network Infrared PYROELECTRIC sensor Energy SAVING lightING System in University CLASSROOM
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Homeostasis Lighting Control System Using a Sensor Agent Robot
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作者 Tatsuya Akiba Akira Mita 《Intelligent Control and Automation》 2013年第2期138-153,共16页
In this study, “homeostasis”, the function by which living things keep their constancy, was emulated as a lighting control for a building space. The algorithm we developed mimics the mechanisms of the endocrine and ... In this study, “homeostasis”, the function by which living things keep their constancy, was emulated as a lighting control for a building space. The algorithm we developed mimics the mechanisms of the endocrine and immune systems. The endocrine system transmits information entirely, whereas the immune system transmits information with a concentration gradient. A lighting control system using the proposed algorithm was evaluated in a simulation and experiment using a sensor agent robot. In this algorithm, a robot recognizes a person’s behavior and uses it to decide his or her preference as to the illuminance. The results indicate that the algorithm can be used to realize a comfortable lighting control in several situations. 展开更多
关键词 HOMEOSTASIS lightING Control sensor AGENT ROBOT Human TRACKING
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Neurochip Based on Light-addressable Potentiometric Sensor
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作者 Qingjun Liu Hua Cai +3 位作者 Ying Xu Lifeng Qin Lijiang Wang Ping Wang 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期413-416,共4页
<正>A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed.Using its light addressable characteristic.The problems of the limitations of restricted discrete active sites of current... <正>A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed.Using its light addressable characteristic.The problems of the limitations of restricted discrete active sites of current neurochips,such as microelectrode array and field effect transistor array can be settled easily.Based on the theoretical analysis of the interface between cells and LAPS,spontaneously discharges of hippocampal neurons induced by Mg~ 2+)-free media treatment were recorded by LAPS.The results demonstrate that this kind of neurochip has potential to monitor electrophysiology of cultured cells in a non-invasive way. 展开更多
关键词 NEUROCHIP cell-based biosensor hippocampal neurons light-addressable potentiometric sensor
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Strategy and Future Prospects to Develop Room-Temperature-Recoverable NO2 Gas Sensor Based on Two-Dimensional Molybdenum Disulfide 被引量:9
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作者 Abhay V.Agrawal Naveen Kumar Mukesh Kumar 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第2期305-362,共58页
Nitrogen dioxide(NO2),a hazardous gas with acidic nature,is continuously being liberated in the atmosphere due to human activity.The NO2 sensors based on traditional materials have limitations of high-temperature requ... Nitrogen dioxide(NO2),a hazardous gas with acidic nature,is continuously being liberated in the atmosphere due to human activity.The NO2 sensors based on traditional materials have limitations of high-temperature requirements,slow recovery,and performance degradation under harsh environmental conditions.These limitations of traditional materials are forcing the scientific community to discover future alternative NO2 sensitive materials.Molybdenum disulfide(MoS2)has emerged as a potential candidate for developing next-generation NO2 gas sensors.MoS2 has a large surface area for NO2 molecules adsorption with controllable morphologies,facile integration with other materials and compatibility with internet of things(IoT)devices.The aim of this review is to provide a detailed overview of the fabrication of MoS2 chemiresistance sensors in terms of devices(resistor and transistor),layer thickness,morphology control,defect tailoring,heterostructure,metal nanoparticle doping,and through light illumination.Moreover,the experimental and theoretical aspects used in designing MoS2-based NO2 sensors are also discussed extensively.Finally,the review concludes the challenges and future perspectives to further enhance the gas-sensing performance of MoS2.Understanding and addressing these issues are expected to yield the development of highly reliable and industry standard chemiresistance NO2 gas sensors for environmental monitoring. 展开更多
关键词 MOS2 NO2 gas sensors light illumination HETEROJUNCTION
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Fabrication of PdSe2/GaAs Heterojunction for Sensitive Near-Infrared Photovoltaic Detector and Image Sensor Application 被引量:3
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作者 Lin-bao Luo Xiu-xing Zhang +6 位作者 Chen Li Jia-xiang Li Xing-yuan Zhao Zhi-xiang Zhang Hong-yun Chen Di Wu Feng-xia Liang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第6期733-742,I0003,共11页
In this study,we have developed a high-sensitivity,near-infrared photodetector based on PdSe2/GaAs heterojunction,which was made by transferring a multilayered PdSe2 film onto a planar GaAs.The as-fabricated PdSe2/GaA... In this study,we have developed a high-sensitivity,near-infrared photodetector based on PdSe2/GaAs heterojunction,which was made by transferring a multilayered PdSe2 film onto a planar GaAs.The as-fabricated PdSe2/GaAs heterojunction device exhibited obvious photovoltaic behavior to 808 nm illumination,indicating that the near-infrared photodetector can be used as a self-driven device without external power supply.Further device analysis showed that the hybrid heterojunction exhibited a high on/off ratio of 1.16×10^5 measured at 808 nm under zero bias voltage.The responsivity and specific detectivity of photodetector were estimated to be 171.34 mA/W and 2.36×10^11 Jones,respectively.Moreover,the device showed excellent stability and reliable repeatability.After 2 months,the photoelectric characteristics of the near-infrared photodetector hardly degrade in air,attributable to the good stability of the PdSe2.Finally,the PdSe2/GaAs-based heterojunction device can also function as a near-infrared light sensor. 展开更多
关键词 van der Waals heterojunction Two dimensional materials Near-infrared light photodetector Image sensor RESPONSIVITY
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Distributed Optical Fiber Sensor for Multi-point Temperature Measurement 被引量:2
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作者 WANGYu-tian LIUZhan-wei HOUPei-guo SHANWei 《Semiconductor Photonics and Technology》 CAS 2004年第3期199-202,共4页
The distributed optical fiber sensing technology is overviewed,which is based on Raman scattering light theory.Basic operation principle,structure,system characteristics and signal processing are discussed.This struct... The distributed optical fiber sensing technology is overviewed,which is based on Raman scattering light theory.Basic operation principle,structure,system characteristics and signal processing are discussed.This structure and method of the signal processing possess of certain spatial resolution,hence will ensure the practicability of system. 展开更多
关键词 OTDR sensorS Raman scattering Stokes scattered light Anti-Stokes scattered light WAVELET
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Combined optical fiber interferometric sensors for the detection of acoustic emission 被引量:2
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作者 LIANG Yi-jun MU Lin-lin LIU Jun-feng YU Xiao-tao 《Optoelectronics Letters》 EI 2008年第3期184-187,共4页
A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms,so it can be use... A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms,so it can be used to monitor the health of large structure. Theoretical analyses indicate that the system can be equivalent to the Michelson interferometer with two optical fiber loop reflectors,and its sensitivity has been remarkably increased because of the decrease of the losses of light energy. PZT is powered by DC regulator to control the operating point of the system,so the system can accurately detect feeble vibration which is generated by ultrasonic waves propagating on the surface of solid. The amplitude and the frequency of feeble vibration signal are obtained by detecting the output light intensity of interferometer and using Fourier transform technique. The results indicate that the system can be used to detect the acoustic emission signals by the frequency characteristics. 展开更多
关键词 Acoustic emissions Acoustics Electric network analysis Fiber optics Fibers Fourier transforms Geodetic satellites INTERFEROMETERS Interferometry Lattice vibrations light sources Michelson interferometers Optical fibers Optical in Acoustic emission sensors Acoustic Emission signals Fiber loop reflectors Fourier Frequency characteristics Interferometric sensors Laser sources light energy light intensities Operating points OPTICAL Vibration signals
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Fiber optic strain twin-sensor-array for smart structural health monitoring 被引量:1
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作者 赵士刚 苑立波 《智能系统学报》 2008年第2期177-180,共4页
A multiplexed white light interferometric fiber optic twin-sensor-array was designed to monitor the structural health of large buildings.In this sensing system,based on a Michelson interferometer,an optical path match... A multiplexed white light interferometric fiber optic twin-sensor-array was designed to monitor the structural health of large buildings.In this sensing system,based on a Michelson interferometer,an optical path matching technique is used to demodulate each twin-sensor.Each twin-sensor-array consists of a 2×N sensing element linked by a 3 dB coupler.When one of the twin-sensor is used to measure strain,variations caused by temperature can be compensated for by referencing the other twin-sensor.The multiplexing capacity of the sensing scheme has been analyzed and experimental results with a 2×3 twin-sensor-array are given. 展开更多
关键词 光纤敏感器 双敏感器数组 干涉仪 多路驱动
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Calibration of line structured light vision system based on camera’s projective center 被引量:7
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作者 ZHU Ji-gui LI Yan-jun YE Sheng-hua 《光学精密工程》 EI CAS CSCD 北大核心 2005年第5期584-591,共8页
Based on the characteristics of line structured light sensor, a speedy method for the calibration was established. With the coplanar reference target, the spacial pose between camera and optical plane can be calibrate... Based on the characteristics of line structured light sensor, a speedy method for the calibration was established. With the coplanar reference target, the spacial pose between camera and optical plane can be calibrated by using of the camera’s projective center and the light’s information in the camera’s image surface. Without striction to the movement of the coplanar reference target and assistant adjustment equipment, this calibration method can be implemented. This method has been used and decreased the cost of calibration equipment, simplified the calibration procedure, improved calibration efficiency. Using experiment, the sensor can attain relative accuracy about 0.5%, which indicates the rationality and effectivity of this method. 展开更多
关键词 投影中心 线性结构 光传感器 标度 可视性系统
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Reflective Ladder Topology Network Based on White Light Fiber-Optic Mach-Zehnder Interferometer
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作者 Song Li Ferhati Mokhtar Li-Bo Yuan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第3期63-66,共4页
In order to improve the multiplexing capability of the optical sensors based on the lower interferential optic fiber sensing technology and the white light fiber-optic Mach-Zehnder interferometer,reflective ladder top... In order to improve the multiplexing capability of the optical sensors based on the lower interferential optic fiber sensing technology and the white light fiber-optic Mach-Zehnder interferometer,reflective ladder topology network ( RLT) with tailored formula was proposed. The topology network consists of 6 rungs sensing elements linked by 5 couplers. Two cases with different choices of couplers were contrasted: one is equal coupling ratio,and the other is tailored coupling ratio. Through the simulation of these two cases,the detailed multiplexing capability was analyzed,and accordingly the experiments were also carried out. The simulation results showed that,the tailored formula enhances the multiplexing capability of the structure. In the first case, the maximum number of sensors which can be multiplexed is 8,and in the other case is 12 fiber optic sensors. The experimental results have a good agreement with numerical simulation results. Thus,it is considered expedient to incorporate RLT into large-scale building,grounds,bridges,dams,tunnels,highways and perimeter security. 展开更多
关键词 fiber-optic sensor white light interferometer MULTIPLEXING technique REFLECTIVE LADDER topology network TAILORED FORMULA
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The validating and identifying of the droplet transfer character signal from arc light in oscillating wire feed mode
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作者 杨世彦 韩明武 王红英 《China Welding》 EI CAS 2002年第1期42-45,共4页
The character of droplet transfer arc light sense signal is studied and validated in oscillating feed mode. And a novel mini photoelectric arc light sensor together with the controlling circuit used to automatically... The character of droplet transfer arc light sense signal is studied and validated in oscillating feed mode. And a novel mini photoelectric arc light sensor together with the controlling circuit used to automatically stabilize the signal range is developed. Further more the automatically identifying of the droplet transfer character signal from arc light is realized reliably. 展开更多
关键词 droplet transfer oscillating wire feeding arc light sensor
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Enhance Egocentric Grasp Recognition Based Flex Sensor Under Low Illumination
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作者 Chana Chansri Jakkree Srinonchat 《Computers, Materials & Continua》 SCIE EI 2022年第6期4377-4389,共13页
Egocentric recognition is exciting computer vision research by acquiring images and video from the first-person overview.However,an image becomes noisy and dark under low illumination conditions,making subsequent hand... Egocentric recognition is exciting computer vision research by acquiring images and video from the first-person overview.However,an image becomes noisy and dark under low illumination conditions,making subsequent hand detection tasks difficult.Thus,image enhancement is necessary to make buried detail more visible.This article addresses the challenge of egocentric hand grasp recognition in low light conditions by utilizing the flex sensor and image enhancement algorithm based on adaptive gamma correction with weighting distribution.Initially,a flex sensor is installed to the thumb for object manipulation.The thumb placement that holds in a different position on the object of each grasp affects the voltage changing of the flex sensor circuit.The average voltages are used to configure the weighting parameter to improve images in the image enhancement stage.Moreover,the contrast and gamma function are used to adjust varies the low light condition.These grasp images are then separated to be training and testing with pretrained deep neural networks as the feature extractor in YOLOv2 detection network for the grasp recognition system.The proposed of using a flex sensor significantly improves the grasp recognition rate in low light conditions. 展开更多
关键词 Egocentric vision hand grasp flex sensor low light enhancement
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Stabilization of Intensity- based Optical Fiber Pressure Sensor
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作者 WANG Li-tian, WANG Yu-tian, ZHENG Long-jiang, HOU Pei-guo (Yanshan University,Qinhuangdao 066004,CHN) 《Semiconductor Photonics and Technology》 CAS 1999年第4期221-225,共5页
A practical optical fiber differential pressure sensor is presented at first. Then the techniques of light source feedback, set up of reference channel, proportional measurement and other methods to improve the stabil... A practical optical fiber differential pressure sensor is presented at first. Then the techniques of light source feedback, set up of reference channel, proportional measurement and other methods to improve the stability of the system as well as to reduce the interference with same nature are emphatically discussed. Finally, the experiment results of the developed instrument are given. 展开更多
关键词 light Intensity Optical Fiber Pressure sensor light Feedback Reference Channel
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Daylight Savings Calculation Technique for Smart Buildings
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作者 Dariusz Kacprzak Ioan Tuleasca 《Intelligent Control and Automation》 2013年第1期102-107,共6页
This publication presents a technique of quantifying energy savings due to daylight. The technique is designated to be used in smart buildings or similar applications where daylight harvesting is welcomed. The techniq... This publication presents a technique of quantifying energy savings due to daylight. The technique is designated to be used in smart buildings or similar applications where daylight harvesting is welcomed. The technique is divided into three stages. In the first stage an optical sensor is evaluated for its P (power)-E (illumination) response characteristics. In the second stage the calibration of room properties is carried out. In the final stage photometric calculations are performed, and energy savings are calculated. The major advantage of the proposed approach is to determine energy savings during the design stage of a building, not after the building construction or retrofitting. The information obtained from the calculations is useful for investors, future tenants and environmentalists. 展开更多
关键词 INTERIOR lightING ELS sensor Energy SAVINGS CO2 EMISSIONS ETAP Appliances
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Sensors for control of water transparency in optical and microwave ranges
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作者 V F Kravchenko E V Krivenko +1 位作者 V I Lutsenko I V Popov 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第4期354-359,共6页
In the face of deteriorating environmental conditions in the world,water quality control is an urgent task.It can be solved by creating sensors with high accuracy and low cost,which requires the development of fundame... In the face of deteriorating environmental conditions in the world,water quality control is an urgent task.It can be solved by creating sensors with high accuracy and low cost,which requires the development of fundamentally new radiophysical methods that take advantage of the optical,microwave and millimeter wavelengths that have a significantly greater sensitivity to low concentrations of pollutants and a lower inertia.The article presents prototypes of measuring cells of the microwave and optical ranges as well as the results of an experimental study of water of various degrees of pollution with their help.The results show that the use of the highly sensitive method of capillary-waveguide resonance makes it possible to detect the presence of micro impurities in water with concentrations up to0.1%and to identify water even from sources of various natural origins.In addition,the use of measurements at several frequencies in the optical range will make it possible to solve the problem of creating water control sensors with high sensitivity to pollution and low cost.It can be concluded that the possibility of complex use of multiwave sensors(optical,infrared and microwave ranges)allows to increase the sensitivity and reliability of water quality assessment. 展开更多
关键词 optical sensor light attenuation in the medium optical transparency capillary-waveguide resonator dielectric characteristics Q-factor and depths of resonance absorption
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Intelligent 3-Way Priority-Driven Traffic Light Control System for Emergency Vehicles
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作者 Joe Essien Felix Uloko 《Open Journal of Applied Sciences》 2023年第8期1207-1223,共17页
The problem of traffic congestion is a significant phenomenon that has had a substantial impact on the transportation system within the country. This phenomenon has given rise to numerous intricacies, particularly in ... The problem of traffic congestion is a significant phenomenon that has had a substantial impact on the transportation system within the country. This phenomenon has given rise to numerous intricacies, particularly in instances where emergency situations occur at traffic light intersections that are consistently congested with a high volume of vehicles. This implementation of a traffic light controller system is designed with the intention of addressing this problem. The purpose of the system was to facilitate the operation of a 3-way traffic control light and provide priority to emergency vehicles using a Radio Frequency Identification (RFID) sensor and Reduced Instruction Set Computing (RISC) Architecture Based Microcontroller. This research work involved designing a system to mitigate the occurrence of accidents commonly observed at traffic light intersections, where vehicles often need to maneuver in order to make way for emergency vehicles following a designated route. The research effectively achieved the analysis, simulation and implementation of wireless communication devices for traffic light control. The implemented prototype utilizes RFID transmission, operates in conjunction with the sequential mode of traffic lights to alter the traffic light sequence accordingly and reverts the traffic lights back to their normal sequence after the emergency vehicle has passed the traffic lights. 展开更多
关键词 RFID sensors MICROCONTROLLER Traffic light Control System RISC Architecture Intelligent Systems
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基于线结构光扫描的烟支表面缺陷检测方法研究 被引量:1
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作者 钟琳 徐海 +4 位作者 米芳芳 赵德华 詹妮 丁凡 牛燕丽 《包装与食品机械》 CAS 北大核心 2024年第2期82-87,共6页
在烟支表面缺陷检测时,为解决传统二维图像方法无法获得深度信息的问题,提出一种基于线结构光传感器旋转扫描的检测方法。烟支在两同向辊轮的旋转带动下实现自转,通过线结构光视觉传感器获取物体轴向轮廓线,使用随机采样一致性拟合轮廓... 在烟支表面缺陷检测时,为解决传统二维图像方法无法获得深度信息的问题,提出一种基于线结构光传感器旋转扫描的检测方法。烟支在两同向辊轮的旋转带动下实现自转,通过线结构光视觉传感器获取物体轴向轮廓线,使用随机采样一致性拟合轮廓线,通过计算原始点到拟合轮廓的距离判断缺陷点。选取某品牌烟支在检测过程中得到的原始数据,其中多组样本的Kappa值均达到0.97,重复性达到99.3%。研究为烟支缺陷检测提供参考。 展开更多
关键词 线结构光视觉传感器 烟支 随机采样一致性 直线拟合
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A Novel Structure of LAPS Array for Cell-Based Biosensor
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作者 Ying Xu Hua Cai +3 位作者 Qingjun Liu Lifeng Qin Lijiang Wang Ping Wang 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期51-54,共4页
The light-addressable potentiometric sensor (LAPS) is a semiconductor-based cellular biosensor with an electrolyte-insulator-semiconductor (EIS) structure.By depositing biocompatible layers on the sensing surface fo... The light-addressable potentiometric sensor (LAPS) is a semiconductor-based cellular biosensor with an electrolyte-insulator-semiconductor (EIS) structure.By depositing biocompatible layers on the sensing surface for cell culture, it can be used to detect bioelectrical parameters of cells.The characteristic curve for photocurrent versus applied bias voltage to the system shows a current-voltage curve (Ⅰ-Ⅴcurve).This technique can be used to detect the action potential changes towards different drugs based on the bias voltage dependence of an optical current,and provides a dynamic system by scanning light beam at the very cell on the sensor device.The LAPS overcomes the limitation of recording sites,but high spatial resolution and sensitivity are also paramount.This paper discussed a novel structure of LAPS array for extracellular monitoring to decrease potential noise level.Both characteristics of active recording array areas and cell culture conditions are measured. 展开更多
关键词 light-addressable potentiometric sensor array LAPS sensitivity cell-based biosensor
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Evaluation and Enhanced Use of Light Emitting Diodes for Hydroponics
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作者 Jayasanka RANAWEERA Siripala RANAWEERA Clarence W.DE SILVA 《Instrumentation》 2019年第3期18-27,共10页
Hydroponic farming is a viable and economical farming method,which can produce safe and healthy greens and vegetables conveniently and at a relatively low cost.It is essential to provide supplemental lighting for crop... Hydroponic farming is a viable and economical farming method,which can produce safe and healthy greens and vegetables conveniently and at a relatively low cost.It is essential to provide supplemental lighting for crops grown in greenhouses to meet the daily light requirement,Daily Light Integral(DLI).The present paper investigates how effectively and efficiently LEDs can be used as a light source in hydroponics.It is important for a hydroponic grower to assess the requirement of photo synthetically active radiation(PAR)or the Photosynthetic Photon Flux Density(PPFD),in a greenhouse,and adjust the quality and quantity of supplemental lighting accordingly.A Quantum sensor(or PAR sensor)can measure PAR more accurately than a digital light meter,which measures the light intensity or illuminance in the SI unit Lux,but a PAR sensor is relatively expensive and normally not affordable by an ordinary farmer.Therefore,based on the present investigation and experimental results,a very simple way to convert light intensity measured with a Lux meter into PAR is proposed,using a simple conversion factor(41.75 according to the present work).This allows a small-scale hydroponic farmer to use a simple and inexpensive technique to assess the day to day DLI values of PAR in a greenhouse accurately using just an inexpensive light meter.The present paper also proposes a more efficient way of using LED light panels in a hydroponic system.By moving the LED light panels closer to the crop,LED light source can use a fewer number of LEDs to produce the same required daily light requirement and can increase the efficiency of the power usage to more than 80%.Specifically,the present work has determined that it is important to design more efficient vertically movable LED light panels with capabilities of switching individual LEDs on and off,for the use in greenhouses.This allows a user to control the number of LEDs that can be lit at a particular time,as required.By doing so it is possible to increase the efficiency of a LED lighting system by reducing its cost of the electricity usage. 展开更多
关键词 HYDROPONICS Grow lights light Emitting Diodes(LEDs) Photosynthesis Photosynthetic Active Radiation(PAR) Photosynthetic Photon Flux Density(PPFD) HPS(High Pressure Sodium) HID(High Intensity Discharge) Daily light Integral(DLI) Quantum sensor Digital light Meter(Lux meter)
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