• 제목/요약/키워드: portable measurement device

검색결과 100건 처리시간 0.026초

IoT를 사용한 센서 네트워크 기반의 실시간 토양 습도 모니터링 (Real-Time Soil Humidity Monitoring Based on Sensor Network Using IoT)

  • 김경헌;김희동
    • 한국전기전자재료학회논문지
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    • 제35권5호
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    • pp.459-465
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    • 2022
  • This paper reports a method to use a wireless sensor network deployed in the field to real-time monitor soil moisture, warning when the moisture level reaches a specific value, and wirelessly controlling an additional device (LED or water supply system, etc.). In addition, we report all processes related to wireless irrigation system, including field deployment of sensors, real-time monitoring using a smartphone, data calibration, and control of additional devices deployed in the field by smartphone. A commercially available open-source Internet of Things (IoT) platform, NodeMCU, was used, which was combined with a 9V battery, LED and soil humidity sensor to be integrated into a portable prototype. The IoT-based soil humidity sensor prototype deployed in the field was installed next to a tree for on-site demonstration for the measurement of soil humidity in real-time for about 30 hours, and the measured data was successfully transmitted to a smartphone via Wifi. The measurement data were automatically transmitted via e-mail in the form of a text file, stored on the web, followed by analyses and calibrations. The user can check the humidity of the soil real-time through a personal smartphone. When the humidity of a soil reached a specific value, an additional device, an LED device, placed in the field was successfully controlled through the smartphone. This LED can be easily replaced by other electronic devices such as water supplies, which can also be controlled by smartphones. These results show that farmers can not only monitor the condition of the field real-time through a sensor monitoring system manufactured simply at a low cost but also control additional devices such as irrigation facilities from a distance, thereby reducing unnecessary energy consumption and helping improve agricultural productivity.

혈중요소 및 혈당농도 측정을 위한 휴대용 측정기 개발 (Development of a portable device for the measurement of urea concentration and glucose concentration in blood)

  • 유재택;이동하
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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    • pp.28-32
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    • 2003
  • 본 논문은 시료의 양을 최소화하고 혈중 요소 및 혈당 농도에 대한 정확한 측정을 위하여 최근에 개발된 전기화학형 마이크로 전극형 센서의 간략한 소개 및 전기적인 특성에 관하여 요약하는 것에서 출발하여 센서로부터 전기신호를 발생시키는 signal conditioning 회로의 설계, microprocessor를 이용한 digital 값으로의 변환 및 data 취득, 취득한 data를 측정된 혈당량 및 요소량으로의 변환 저장 display까지의 휴대용 계측기의 prototype 개발에 관하여 기술한다. 이 계측기는 미량의 혈액채취 한번으로 농도를 측정하는 측정모드와, 측정된 data를 찾아보기 위한 검색모드로 작동시킬 수 있다. Microprocessor의 기능을 최대한 사용하여 측정기의 크기를 소형화하였으며 LCD(Liquid crystal display)틀 채택하는 등 저전력 회로로 구현하였다.

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포터블 EEG를 활용한 콘텐츠 몰입도 평가 (Measurement of degree of contents immersion with using the portable EEG device)

  • 금남호;이택;이정빈;인호
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2015년도 추계학술발표대회
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    • pp.1681-1684
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    • 2015
  • 최근 소형 모바일 디바이스가 발달함에 따라 시간적, 공간적 제약이 없이 대량의 콘텐츠가 소비되고 있는 환경에서 콘텐츠 소비 만족도 및 몰입도를 측정하기 위해 사용자 피드백을 설문 조사하는 기존 방식은 비효율적이다. 왜냐하면 수작업에 의존하고 객관성이 결여된 데이터가 수집될 가능성이 있기 때문이다. 따라서 최근 연구에서는 EEG를 활용한 방법이 하나의 대안으로 제시되고 있다. 본 논문에서는 기존 설문조사 방식의 한계점을 보완하고 기존 EEG방식의 단점을 개선하기 위한 포터블 EEG를 활용하는 방법을 제안하였다. 소형 및 간편함을 확보하기 위하여 배터리 환경에 비 접착식 단일전극을 이용하여 EEG를 측정하고 주파수 분석을 통하여 집중력과 관련된 파형을 분리, 콘텐츠 몰입도를 점수화 하였다. 마지막으로 실험을 통해 앞서 산출한 점수와 콘텐츠의 흥미도가 비례관계에 있음을 증명하였다.

Noninvasive blood glucose monitoring system based on NIR spectroscopy with a contact pressure control device

  • Kang, Na-Roo;Baek, Ju-Hyun;Woo, Young-Ah;Kim, Hyo-Jin
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.67.3-68
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    • 2003
  • The purpose of this study is to improve repeatability of a non-invasive blood glucose measurement. The portable NIR system that was newly integrated by our lab includes a tungsten halogen lamp, a specialized reflectance fiber optic probe and a photo diode array type InGaAs detector, which was developed by a microchip technology based on the lithography. Reflectance NIR spectra of finger tip were recorded by using a fiber optic probe. The probe was fixed in the system and subjects put their finger on the probe head. (omitted)

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Design and Implementation of an FPGA-based Real-time Simulator for a Dual Three-Phase Induction Motor Drive

  • Gregor, Raul;Valenzano, Guido;Rodas, Jorge;Rodriguez-Pineiro, Jose;Gregor, Derlis
    • Journal of Power Electronics
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    • 제16권2호
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    • pp.553-563
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    • 2016
  • This paper presents a digital hardware implementation of a real-time simulator for a multiphase drive using a field-programmable gate array (FPGA) device. The simulator was developed with a modular and hierarchical design using very high-speed integrated circuit hardware description language (VHDL). Hence, this simulator is flexible and portable. A state-space representation model suitable for FPGA implementations was proposed for a dual three-phase induction machine (DTPIM). The simulator also models a two-level 12-pulse insulated-gate bipolar transistor (IGBT)-based voltage-source converter (VSC), a pulse-width modulation scheme, and a measurement system. Real-time simulation outputs (stator currents and rotor speed) were validated under steady-state and transient conditions using as reference an experimental test bench based on a DTPIM with 15 kW-rated power. The accuracy of the proposed digital hardware implementation was evaluated according to the simulation and experimental results. Finally, statistical performance parameters were provided to analyze the efficiency of the proposed DTPIM hardware implementation method.

전자소자를 이용한 인간 감성지표 코티졸 검출에 관한 기초연구 (A pilot study on measuring the human cortisol using an electronic device)

  • 이희조;이정현;황유선;정효일
    • 감성과학
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    • 제14권4호
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    • pp.531-536
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    • 2011
  • 감성과학에서 인간의 감성을 손쉽게 측정할 수 있는 기술이나 기법 등은 매우 중요한 분야이다. 최근 마음의 변화는 몸의 변화를 수반한다(정신신경증면역내분비학, psychoneuroimmunoendocrinology)는 전제하에 인간 감성을 체액을 통해서 측정하는 시도가 이루어지고 있다. 몸의 변화 중에 최근까지 가장 많이 연구된 것은 스트레스에 관한 것으로 이를 측정하는 지표로는 코티졸(cortisol)이라는 물질이 널리 알려져 오고 있다. 코티졸을 측정하는 기존의 방법을 열거하면 High Performance Liquid Chromatography (HPLC), fluorometric assay, reverse phase chromatography 등이 대표적인데 모두 시간이 많이 걸리고 가격이 비싸며 휴대용이 아니기에 POCT (point of care testing)에 적합하지 않다. 이에 본 연구진은 소형 초고주파 공진 소자를 만들어 타액 속의 코티졸을 측정할 수 있는 항체를 고정하고 이것이 코티졸과 결합할 때 나오는 공진신호를 읽음으로써 환자의 타액 속 코티졸을 쉽고 빠르게 측정할 수 있는 기법을 소개한다. 본 연구를 위해 제안된 공진소자는 밀리미터 크기의 소자로서 제작이 용이하며 간단한 형태이다. 최종적으로 소자표면상에 결합되는 코티졸 농도변화(100, 10, 1, 0.1 ng/ml)에 따라 거의 선형적인 주파수응답(11, 10, 9, 7 MHz) 특성을 보인다. 100 pg/ml에 해당하는 적은 코티졸의 양까지 거의 실시간에 가까운 빠른 시간 안에서 쉽게 검출이 가능하며, 뿐만 아니라 표지(labeling)가 필요 없는 장점을 가지고 있다. 이러한 농도에 따른 주파수 변화를 기반으로 하는 코티졸 감성지표센서는 무선단말시스템에 적용될 수 있는 가능성과 응용성을 가지고 있다.

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Performance evaluation study of a commercially available smart patient-controlled analgesia pump with the microbalance method and an infusion analyzer

  • Park, Jinsoo;Jung, Bongsu
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제22권2호
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    • pp.129-143
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    • 2022
  • Background: Patient-controlled analgesia (PCA) has been widely used as an effective medical treatment for pain and for postoperative analgesia. However, improper dose errors in intravenous (IV) administration of narcotic analgesics from a PCA infusion pump can cause patient harm. Furthermore, opioid overdose is considered one of the highest risk factors for patients receiving pain medications. Therefore, accurate delivery of opioid analgesics is a critical function of PCA infusion pumps. Methods: We designed a microbalance method that consisted of a closed acrylic chamber containing a layer and an oil layer with an electronic balance. A commercially available infusion analyzer (IDA-5, Fluke Co., Everett, WA, USA) was used to measure the accuracy of the infusion flow rate from a commercially available smart PCA infusion pump (PS-1000, UNIMEDICS, Co., Ltd., Seoul, Korea) and compared with the results of the microbalance method. We evaluated the uncertainty of the flow rate measurement using the ISO guide (GUM:1995 part3). The battery life, delay time of the occlusion alarm, and bolus function of the PCA pump were also tested. Results: The microbalance method was good in the short-term 2 h measurement, and IDA-5 was good in the long-term 24 h measurement. The two measurement systems can complement each other in the case of the measurement time. Regarding battery performance, PS-1000 lasted approximately 5 days in a 1 ml/hr flow rate condition without recharging the battery. The occlusion pressure alarm delays of PS-1000 satisfied the conventional alarm threshold of occlusion pressure (300-800 mmHg). Average accuracy bolus volume was measured as 63%, 95%, and 98.5% with 0.1 ml, 1 ml, and 2 ml bolus volume presets, respectively. A 1 ml/hr flow rate measurement was evaluated as 2.08% of expanded uncertainty, with a 95% confidence level. Conclusion: PS-1000 showed a flow accuracy to be within the infusion pump standard, which is ± 5% of flow accuracy. Occlusion alarm of PS-1000 was quickly transmitted, resulting in better safety for patients receiving IV infusion of opioids. PS-1000 is sufficient for a portable smart PCA infusion pump.

Fuzzy 알고리즘을 이용한 엘리베이터 안전진단 및 동특성 분석 포터블 장비 개발 (A study on the Development of the Portable Device for Safety Diagnosis and Dynamic Characteristics Analysis of Elevator using Fuzzy Algorithm)

  • 김태형;김훈모
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.199-202
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    • 2001
  • An elevator system, which is essential equipment for vertical movement of an object, as a property of building, has been driven by various expenditures and purposes. Since developing electrical control technology, control system are highly developed. The elevator system has expanded widely, but a data accuracy acquisition technique and safety predict technique for securing system safety is still at a basic level. So, objective verification for elevator confidence condition requires an absolute accuracy measurement technique. Therefore, this study is executed in order to acquire a method of depending on sense of a manager with simple numeric measurement data, and to construct a logical, analytical foresight system for more efficient elevator management system. As an artificial intelligence for diagnosis, the fuzzy inference algorithm is used for foreseeing the system in this thesis, because the fuzzy algorithm is the most useful method for resolving subjective ideas and a vague judgment of humans. The fuzzy inference algorithm is developed for each sensor signal(i.e. vibration, velocity, current).

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사물인터넷 기반 미세먼지 모니터링 시스템 설계 및 구현 (Design of Fine Dust Monitoring System based on the Internet of Things)

  • 김태연
    • 한국정보전자통신기술학회논문지
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    • 제15권1호
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    • pp.14-26
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    • 2022
  • 최근 대기환경오염의 심각성이 커짐에 따라 대기오염에 대한 관심도가 높아지고 있다. 본 논문에서 제안한 사물 인터넷 기반 미세먼지 모니터링 시스템은 대기환경오염 중 인체에 영향을 미치는 가장 큰 원인인 미세먼지, 휘발성 유기화합물, 이산화탄소 등을 측정하고 모니터링 할 수 있도록 하였다. 미세먼지 모니터링 시스템은 대기환경정보를 측정할 수 있는 측정 장치, 측정된 정보를 저장 및 분석할 수 있는 서버 시스템, 대기환경정보를 실시간으로 시각화 분석이 가능하도록 관리자용 통합 모니터링 관리 시스템과 사용자용 스마트 폰 애플리케이션으로 구성하여 하였다. 또한, 시스템의 응답속도, 센서 데이터의 전송속도, 센서의 측정오차를 이용하여 제안한 사물인터넷 기반 미세먼지 모니터링 시스템의 효율성을 검증하고자 하였다. 사물인터넷 기반 미세먼지 모니터링 시스템은 대기환경정보를 휴대용 미세먼지 측정 장치로 측정한 후 대기오염상태를 시각화함으로써 사용자의 편리성과 시스템의 효율성을 증대시킬 수 있을 것이라 기대한다.

Calibration of Portable Particulate Mattere-Monitoring Device using Web Query and Machine Learning

  • Loh, Byoung Gook;Choi, Gi Heung
    • Safety and Health at Work
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    • 제10권4호
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    • pp.452-460
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    • 2019
  • Background: Monitoring and control of PM2.5 are being recognized as key to address health issues attributed to PM2.5. Availability of low-cost PM2.5 sensors made it possible to introduce a number of portable PM2.5 monitors based on light scattering to the consumer market at an affordable price. Accuracy of light scatteringe-based PM2.5 monitors significantly depends on the method of calibration. Static calibration curve is used as the most popular calibration method for low-cost PM2.5 sensors particularly because of ease of application. Drawback in this approach is, however, the lack of accuracy. Methods: This study discussed the calibration of a low-cost PM2.5-monitoring device (PMD) to improve the accuracy and reliability for practical use. The proposed method is based on construction of the PM2.5 sensor network using Message Queuing Telemetry Transport (MQTT) protocol and web query of reference measurement data available at government-authorized PM monitoring station (GAMS) in the republic of Korea. Four machine learning (ML) algorithms such as support vector machine, k-nearest neighbors, random forest, and extreme gradient boosting were used as regression models to calibrate the PMD measurements of PM2.5. Performance of each ML algorithm was evaluated using stratified K-fold cross-validation, and a linear regression model was used as a reference. Results: Based on the performance of ML algorithms used, regression of the output of the PMD to PM2.5 concentrations data available from the GAMS through web query was effective. The extreme gradient boosting algorithm showed the best performance with a mean coefficient of determination (R2) of 0.78 and standard error of 5.0 ㎍/㎥, corresponding to 8% increase in R2 and 12% decrease in root mean square error in comparison with the linear regression model. Minimum 100 hours of calibration period was found required to calibrate the PMD to its full capacity. Calibration method proposed poses a limitation on the location of the PMD being in the vicinity of the GAMS. As the number of the PMD participating in the sensor network increases, however, calibrated PMDs can be used as reference devices to nearby PMDs that require calibration, forming a calibration chain through MQTT protocol. Conclusions: Calibration of a low-cost PMD, which is based on construction of PM2.5 sensor network using MQTT protocol and web query of reference measurement data available at a GAMS, significantly improves the accuracy and reliability of a PMD, thereby making practical use of the low-cost PMD possible.