• Title/Summary/Keyword: Sensing type

Search Result 1,087, Processing Time 0.028 seconds

Data-centric Sensor Middleware for Heterogeneous Sensor Networks (이기종 센서 네트워크를 위한 데이터 중심적 센서 미들웨어)

  • Nam, Choon-Sung;Shin, Dong-Ryeol
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.7 no.6
    • /
    • pp.323-330
    • /
    • 2012
  • Wireless sensor networks need middleware system for efficiently managing the constrained resource and sensing data because they need different sensing data type and protocol to communicate with heterogeneous sensor networks. Thus this paper proposes data-centric sensor middleware for heterogeneous sensor networks. The proposed middleware have to support various query processing of user applications, high-level request of users, manage heterogeneous sensor systems and universal sensing data type for node and user application.

Fabrication of CuO/ZnO Nano-heterostructure by Photochemical Method and Their H2S Gas Sensing Properties

  • Kim, Jae-Hyun;Yong, Ki-Jung
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2011.08a
    • /
    • pp.359-359
    • /
    • 2011
  • This study reports the H2S gas sensing properties of CuO / ZnO nano-hetero structure bundle and the investigation of gas sensing mechanism. The 1-Dimensional ZnO nano-structure was synthesized by hydrothermal method and CuO / ZnO nano-heterostructures were prepared by photo chemical reaction. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectra confirmed a well-crystalline ZnO of hexagonal structure. In order to improve the H2S gas sensing properties, simple type of gas sensor was fabricated with ZnO nano-heterostructures, which were prepared by photo-chemical deposition of CuO on the ZnO nanorods bundle. The furnace type gas sensing system was used to characterize sensing properties with diluted H2S gas (50 ppm) balanced air at various operating temperature up to 500$^{\circ}C$. The H2S gas response of ZnO nanorods bundle sensor increased with increasing temperature, which is thought to be due to chemical reaction of nanorods with gas molecules. Through analysis of X-ray photoelectron spectroscopy (XPS), the sensing mechanism of ZnO nanorods bundle sensor was explained by well-known surface reaction between ZnO surface atoms and hydrogen sulfide. However at high sensing temperature, chemical conversion of ZnO nanorods becomes a dominant sensing mechanism in current system. Photo-chemically fabricated CuO/ZnO heteronanostructures show higher gas response and higher current level than ZnO nanorods bundle. The gas sensing mechanism of the heteronanostructure can be explained by the chemical conversion of sensing material through the reaction with H2S gas.

  • PDF

Relationships between Myers-Briggs Type Indicator (MBTI) Psychological Type and Marital Satisfaction, Divorce Proneness, Positive Affect, and Conflict Regulation in Clinic Couples (부부클리닉 방문부부의 MBTI 성격유형과 결혼만족도, 이혼가능성, 긍정적 감정, 갈등조정방식의 관계)

  • Kong, Seong-Sook
    • Journal of Korean Academy of Nursing
    • /
    • v.40 no.3
    • /
    • pp.336-348
    • /
    • 2010
  • Purpose: The purpose of the study was to investigate the relationships between the Myers-Briggs Type Indicator (MBTI) psychological type and marital satisfaction, divorce proneness, positive affect, and conflict regulation in couple visiting a clinic. Methods: Couples (n=62) who visited "M" couple clinic participated in the study. Data were collected from March to June 2009 using the Marital Satisfaction Scale, Marital Status Inventory, Positive Affect Inventory, and Conflict Regulation Inventory. Results: The couples showed no significant differences in marital satisfaction, positive affect, and conflict regulation according to similarities between spouses in MBTI types. However, they showed significant differences in divorce proneness of husband according to a similarity in the Sensing/Intuition indicator. They also showed significant differences in divorce proneness, positive affect, and conflict regulation between the couples for ISTJ (Introversion, Sensing, Thinking, Judging) or ESTJ (Extraversion, Sensing, Thinking, Judging) types compared to other couples. Conclusion: When nurses counsel couples, they should understand that differences in psychological type between spouses affects their marital relationship. In addition, nurses should educate couples on the characteristics of each type according to the couple's types and help them to understand each other, especially for couples where one spouse is the ISTJ/ESTJ type. These interventions will improve marital satisfaction and prevent the divorce in these couples.

$CO_{2}$ sensing characteristics of solid electrolyte gas sensor with the sensing membrane prepared by the mixture of alkali metal carbonate and binder (알카리 금속 탄산염과 결착제의 혼합물을 감지물질로 하는 고체전해질 가스센서의 $CO_{2}$ 감응 특성)

  • Chai, Yu-Sug;Song, Kap-Duk;Kang, Bong-Hwi;Seo, Moo-Gyo;Lee, Duk-Dong
    • Journal of Sensor Science and Technology
    • /
    • v.7 no.2
    • /
    • pp.111-116
    • /
    • 1998
  • The simple solid electrolyte carbon dioxide sensor with heaters were fabricated by using Li ionic conductor. Two Au electrodes were used for the reference and sensing electrode respectively. Two types of gas sensors, type ( I ) and type (II), were fabricated. Type ( I ) sensor was fabricated by the method of melting and crystallizing alkali metal carbonate at the temperature of $420{\sim}500^{\circ}C$. The sensing membrane of type (II) sensor was formed by the printing method on sensing electrode after metal carbonate was mixed with binder. The response characteristics of sensors fabricated for the carbon dioxide were investigated for a range of $CO_{2}$ concentration from 950 ppm to 9,950 ppm at operating temperature $420^{\circ}C$. Type ( I ) sensor and type (II) sensor showed the sensitivity of 62 mV/decade and 65 mV/decade respectively. The emf/decade of type (II) sensor tested at $420^{\circ}C$ almost followed the theoretical value of Nernst's equation and showed stable response characteristics with the fast response time of $15{\sim}20$ sec. Also type (II) sensor showed excellent stability and reproduction properties for 60 days.

  • PDF

A COMPARISON OF OBJECTED-ORIENTED AND PIXELBASED CLASSIFICATION METHODS FOR FUEL TYPE MAP USING HYPERION IMAGERY

  • Yoon, Yeo-Sang;Kim, Yong-Seung
    • Proceedings of the KSRS Conference
    • /
    • v.1
    • /
    • pp.297-300
    • /
    • 2006
  • The knowledge of fuel load and composition is important for planning and managing the fire hazard and risk. However, fuel mapping is extremely difficult because fuel properties vary at spatial scales, change depending on the seasonal situations and are affected by the surrounding environment. Remote sensing has potential of reduction the uncertainty in mapping fuels and offers the best approach for improving our abilities. This paper compared the results of object-oriented classification to a pixel-based classification for fuel type map derived from Hyperion hyperspectral data that could be enable to provide this information and allow a differentiation of material due to their typical spectra. Our methodological approach for fuel type map is characterized by the result of the spectral mixture analysis (SMA) that can used to model the spectral variability in multi- or hyperspectral images and to relate the results to the physical abundance of surface constitutes represented by the spectral endmembers. Object-oriented approach was based on segment based endmember selection, while pixel-based method used standard SMA. To validate and compare, we used true-color high resolution orthoimagery

  • PDF

Preceding Study on the Sensing Part of Level Measurement System of Launch Vehicle Propellant Tanks (발사체 탱크 추진제 수위 측정시스템 감지부 선행연구)

  • Shin, Dong-Sun;Lee, Eung-Shin;Ko, Hyun-Seok;Cho, In-Hyun
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2009.11a
    • /
    • pp.54-57
    • /
    • 2009
  • The propellant level measurement system of the next Koreanized launch vehicle shall adapt a capacitive type sensor, which can generate capacitive values continuously considering cryogenic environment and the characteristics of flowrate control. At present there are a twin-arc and a triple-arc methods as a capacitive type signal sensing method. In this study a highly accurate triple-arc method, which can apply to almost all fluids, is chosen. In this paper the review results on the principle of triple-arc sensing, the analysis results on the influence on capacitive values due to shape change of sensing part, and the simulation results to monitor the influence on signal sensing according to the location of sensing part in the upper part of propellant tank are included. Information obtained from this study can be used in the designing and manufacturing of on-board propellant level measurement system in tanks.

  • PDF

Introduce and application of the angular velocity sensing type of wheel flange lubricator for the railways in KOREA (국내 철도차량용 각속도 감지식 도유기의 적용 및 소개)

  • La, Won-Ki;Yang, Bang-Sub;Lee, Won-Sang;Chang, Dae-Sung
    • Proceedings of the KSR Conference
    • /
    • 2010.06a
    • /
    • pp.958-962
    • /
    • 2010
  • Most of operating railways in domestic, it is used to be Wheel flange lubricator system applied liquid spray type. Wheel flange lubricator are reduced the abrasion of wheel flange through spraying in accordance with operating on the curve or operating function of time base and/or distance base. this paper is written to introduce and study the efficiency for the angular velocity sensing type of lubricant systems.

  • PDF

Excellent Carbon Monoxide Sensing Performance of Au-Decorated SnO2 Nanofibers

  • Kim, Jae-Hun;Zheng, Yifang;Mirzaei, Ali;Kim, Sang Sub
    • Korean Journal of Materials Research
    • /
    • v.26 no.12
    • /
    • pp.741-750
    • /
    • 2016
  • Nanofibers(NFs), because of their high surface area and nanosized grains, have appropriate morphologies for use in chemiresistive-type sensors for gas detection applications. In this study, a highly sensitive and selective CO gas sensing material based on Au-decorated $SnO_2$ NFs was fabricated by electrospinning. $SnO_2$ NFs were synthesized by electrospinning and subsequently decorated with various amounts of Au nanoparticles(NPs) by sputtering; this was followed by thermal annealing. Different characterizations showed the successful formation of Au-decorated $SnO_2$ NFs. Gas sensing tests were performed on the fabricated sensors, which showed bell-shaped sensing behavior with respect to the amount of Au decoration. The best CO sensing performance, with a response of ~20 for 10 ppm CO, was obtained at an optimized amount of Au (2.6 at.%). The interplay between Au and $SnO_2$ in terms of the electronic and chemical sensitization by Au NPs is responsible for the great improvement in the CO sensing capability of pure $SnO_2$ NFs, suggesting that Au-decorated $SnO_2$ NFs can be a promising material for fabricating highly sensitive and selective chemiresistive-type CO gas sensors.

Development of Estimation Method of Sensing Ability of $2^{nd}$ Smart Sensor (2차 스마트 센서의 센싱능력 평가기법 개발)

  • 황성연;홍동표;강희용;박준홍
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.10a
    • /
    • pp.209-213
    • /
    • 1997
  • This paper deals with sensing ability of $2^{nd}$ smart sensor that has a sensing ability of distinguish materials. We have developed new signal processing method that have distinguish different materials. We made the $2^{nd}$ smart sensor for experiment. The second type of smart sensor is HH type. We have developed a new signal processing method that can distinguish among different materials. The estimation method (RSAIIn dex) is developed for $2^{nd}$ smart sensor(HH smart sensor). Experiment and analysis are executed for estimation the new method. We estimated sensing ability of $2^{nd}$ smart sensor with RsA, method. Sensing Ability of the $2^{nd}$ smart sensor were evaluated relatively through a new RsAl method. According to frequency changing, influences of the $2^{nd}$ smart sensor are evaluated through a new recognition index RSAI. Applications of this method are for finding abnormal conditions of objects (automanufacturing), feeling of objects (medical product), robotics, safety diagnosis of structure, etc.

  • PDF

Studies on the Sensing Charcteristics of Carbon-monoxide Using the Maghemite (Maghemite를 이용한 일산화탄소 감지 특성에 관한 연구)

  • 박영구
    • Journal of Environmental Health Sciences
    • /
    • v.21 no.4
    • /
    • pp.24-31
    • /
    • 1995
  • Gas sensing element, $\alpha-Fe_2O_3$ was synthesized by dehydration, reduction, and oxidation of $\alpha-FeOOH$, which was synthesized with $FeSO_4\cdot 7H_2O$ and NaOH. They were produced as a bulk-type, a thick film-type. Then, their responses and mechanisms of response to the gas of carbon monoxide were studied. The qualities of gas sefising elements are decided by the structure and the relative surface area. In the process of $\alpha-FeOOH$ synthesis, the effects of reaction conditions as the equivalent ratio, on the structure and the relative surface area of gas sensing element were observed. The changes of the structure were measured with XRD, SEM,TG-DTA and BET. The resistance changes of the synthesized gas sensor in the air were measured. The response ratio were also measured for the changes of working temperature and gas concentration. As a result of analysis with XRD, it was confirmed that the the best conditions for the synthesis of $\alpha-FeOOH$ were equivalent ratio 0.65. The thick film-type element of $\gamma-Fe_2O_3$ responded more quickly than the bulk-type did. The structure and the relative surface area of the $\rho-FeOOH$ were confirmed as the important factors deciding gas response charcteristics.

  • PDF