• 제목/요약/키워드: Temperature Sensitivity

검색결과 1,719건 처리시간 0.031초

Qualification for Impedance-based Rain Detectors

  • Lee, Sang-Wook;Choi, Byung Il;Kim, Jong Chul;Woo, Sang-Bong;Kim, Yong-Gyoo
    • 센서학회지
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    • 제26권3호
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    • pp.149-154
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    • 2017
  • Detection of rain is one of the essential weather factors that are monitored by automatic weather stations in Korea. In this work, we studied the operation standards required for impedance-based rain detectors in terms of surface temperature and sensitivity, in an effort to establish a qualification procedure for rain detectors. The surface temperature of rain detectors was measured at varying air temperatures from $-30^{\circ}C$ to $20^{\circ}C$, considering the hypothetical presence and absence of rain/snow. In addition, the sensitivity of rain detectors was studied generating artificial raindrops of regular size. The sensitivity was evaluated in terms of the critical number of droplets that triggers the activation of the rain detector. We found that the sensitivity is affected by stationary, horizontal, and vertical droplet deposition methods. The critical number of droplets for the stationary deposition is higher than that for both horizontal and vertical depositions, which provides the maximum limit of droplets required to activate the detector. Based on our experiments considering surface temperature measurements and sensitivity tests, we suggest a revised version of surface temperature and sensitivity requirements for the qualification of impedance-based rain detectors.

레이저 표면 경화처리 긍정변수의 민감도 해석에 관한 연구 (A study on the sensitivity analysis of processing parameters for the laser surface hardening treatment)

  • 이세환;양영수
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2000년도 특별강연 및 추계학술발표대회 개요집
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    • pp.260-263
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    • 2000
  • A methodology is developed and many used to evaluate the response sensitivity of the thermal systems to variations in their design parameters. Technique for computing the sensitivity of temperature distributions to changes in processing parameters needed for deciding the more effective laser input parameters for laser surface hardening treatment are considered. In this study, a state equation governing the heat flow in laser surface treatment is analyzed using a three-dimensional finite element method and sensitivity data of the processing parameter obtained using a direct differentiation method applied for sensitivity analysis. The interesting processing parameter is taken as the laser scan velocity and characteristic beam radius( $r_{b}$) of the sensitivity of the temperature T versus v and $r_{b}$ is analyzed. And these sensitivity results obtained in another parameters are fixed condition. To verifying the numerical analysis results, hardened layer dimensions (width and depth) of the numerical analysis compared with the results of an experimental data.ata.

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유한요소법을 이용한 레이저 표면경화처리 공정변수의 민감도 해석 (Sensitivity Analysis of Processing Parameters for the Laser Surface Hardening Treatment by Using the Finite Element Method)

  • 이세환;양영수
    • Journal of Welding and Joining
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    • 제19권2호
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    • pp.228-234
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    • 2001
  • A methodology is developed and used to evaluate the response sensitivity of the thermal systems to variations in their design parameters. Technique for computing the sensitivity of temperature distributions to changes in processing parameters needed to decide the more effective laser input parameters for laser surface hardening treatment is considered. In this study, a state equation governing the heat flow in laser surface treatment is analyzed using a three-dimensional finite element method and sensitivity data of the processing parameter obtained using a direct differentiation method is applied to the sensitivity analysis. The interesting processing parameters are taken as the laser scan velocity and laser beam radius ( $r_{ b}$), and the sensitivities of the temperature T versus v and $r_{b}$ are analyzed. These sensitivity results are obtained with another parameters fixed. To verify the numerical analysis results, hardened layer dimensions (width and depth) of the numerical analysis are compared with the experimental ones.nes.

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시간대별 기온을 이용한 전력수요예측 알고리즘 개발 (Development of Short-Term Load Forecasting Algorithm Using Hourly Temperature)

  • 송경빈
    • 전기학회논문지
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    • 제63권4호
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    • pp.451-454
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    • 2014
  • Short-term load forecasting(STLF) for electric power demand is essential for stable power system operation and efficient power market operation. We improved STLF method by using hourly temperature as an input data. In order to using hourly temperature to STLF algorithm, we calculated temperature-electric power demand sensitivity through past actual data and combined this sensitivity to exponential smoothing method which is one of the STLF method. The proposed method is verified by case study for a week. The result of case study shows that the average percentage errors of the proposed load forecasting method are improved comparing with errors of the previous methods.

A Novel Behavior, Bang-Sensitive Paralysis, Associated With The shibire Locus of Drosophila melanogaster

  • 김윤택
    • 한국환경성돌연변이발암원학회지
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    • 제10권2호
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    • pp.93-106
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    • 1990
  • The Drosophila temperature-sensitive mutant shibire (shi) is paralyzed at restrictive temperature by a reversible block in synaptic transmission. To explore the functional relationship among shi gene products, viability and temperature-sensitive paralytic behavior were quantitaively analyzed for four shi alleles, shi$^{ts1}$, shi$^{ts2}$, shi$^{ts4}$, and shi$^{ST139}$, and their heteroallelic combinations. The hemizygous combination of shi alleles over deficiency was not completely lethal. shi$^{ts2}$ exhibited distinctively higher viability than other alleles. A novel behavior, bang sensitivity, was also found in shi/Df(1). This bang-sensitive paralytic behavior was compared with that of the typical bang-sensitive mutant flies. Heterozygotes, shi/+, are more severe in temperature sensitivity than deficiency hemizygotes, Df(1)/+. Heteroallelic combinations of shi were less sensitive to high temperature than homozygotes. Among all allelic combinations, shi$^{ts2}$/shi$^{ts4}$ showed an unexpected extreme reduction in temperature sensitivity. The results of allelic interactions among 4 shi alleles suggest that the shi mutations examined behave as antimorphic alleles and that the gene product of shi are likely to function in multimeric forms.

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급냉응고된 과공정 Al-Si합금의 고온변형특성에 관한 연구 (High Temperature Deformation Behavior of Rapid-Solidification Processed Al-18Si Alloy)

  • 김성일
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 춘계학술대회논문집
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    • pp.183-186
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    • 2000
  • The high temperature deformation behavior of spray-formed Al-19wt%Si-1.87wt%Mg-0.085wt.%Fe alloy was studied by torsion testing in the strain rate range of 0.001-1 sec-1 and in the temperature range of 300-500 $^{\circ}C$. The relationship between stress temperature and strain rate is expressed using the Power law. the behavior of dynamic recrystallization is showed in 300-35$0^{\circ}C$, 1-0.1sec-1 and the behavior of dynamic recovery is showed in 450-50$0^{\circ}C$, 0.01-0.001sec-1 The size of Si particles is mall when the temperature is low and the strain rate is high. The strain rate sensitivity(m) and the apparent activation energy(Q) indicate the dependence on strain rate and temperature for flow stress respectively. The hot ductility is high when m is high and Q is low. The maps of strain rate sensitivity and apparent activation energy suggest the optimum processing conditions.

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고온용 고감도 실리콘 홀 센서의 제작 및 특성 (Fabrication and Characteristics of High-sensitivity Si Hall Sensors for High-temperature Applications)

  • 정귀상;노상수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.565-568
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    • 2000
  • This paper describes on the temperature characteristics of a SDB(silicon-wafer direct bonding) SOI(silicon-on-insulator) Hall sensor. Using the buried oxide $SiO_2$ as a dielectrical isolation layer, a SDB SOI Hall sensor without pn junction isolation has been fabricated on the Si/$SiO_2$/Si structure. The Hall voltage and the sensitivity of the implemented SOI Hall sensor show good linearity with respect to the applied magnetic flux density and supplied current. In the temperature range of 25 to $300^{\circ}C$, the shifts of TCO(temperature coefficient of the offset voltage) and TCS(temperature coefficient of the product sensitivity) are less than $\pm 6.7$$\times$$10^{-3}$/$^{\circ}C$ and $\pm 8.2$$\times$$10^{-4}$/$^{\circ}C$respectively. These results indicate that the SDB SOI structure has potential for the development of a silicon Hall sensor with a high-sensitivity and hip high-temperature operation.

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Research on Temperature Sensing Characteristics of Fiber Bragg Grating in Wide Temperature Range

  • Naikui Ren;Hongyang Li;Nan Huo;Shanlong Guo;Jinhong Li
    • Current Optics and Photonics
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    • 제8권2호
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    • pp.162-169
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    • 2024
  • This study investigates the temperature sensitivities of fiber Bragg grating (FBG) across a broad temperature spectrum ranging from -196 ℃ to 900 ℃. We developed the FBG temperature measurement system using a high-temperature tubular furnace and liquid nitrogen to supply consistent high and low temperatures, respectively. Our research showed that the FBG temperature sensitivity changed from 1.55 to 10.61 pm/℃ in the range from -196 ℃ to 25 ℃ when the FBG was packaged with a quartz capillary. In the 25-900 ℃ range, the sensitivity varied from 11.26 to 16.62 pm/℃. Contrary to traditional knowledge, the FBG temperature sensitivity was not constant. This inconsistency primarily stems from the nonlinear shifts in the thermo-optic coefficient and thermal expansion coefficient across this temperature spectrum. The theoretically predicted and experimentally determined temperature sensitivities of FBGs encased in quartz capillary were remarkably consistent. The greatest discrepancy, observed at 25 ℃, was approximately 1.3 pm/℃. Furthermore, it was observed that at 900 ℃, the FBG was rapidly thermally erased, exhibiting variable reflected intensity over time. This study focuses on the advancement of precise temperature measurement techniques in environments that experience wide temperature fluctuations, and has considerable potential application value.

개인별 체감 온도를 반영한 개인 소장 의류 추천 시스템 개발 (Development of a Personal Clothing Recommendation System that Reflects Individual Temperature Sensitivity)

  • 정병희;김우석;이상용
    • 디지털융복합연구
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    • 제19권2호
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    • pp.357-363
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    • 2021
  • 일반적으로 사람들은 외출 시 실시간 날씨 및 기온 등을 참고하여 입고 나갈 의류를 선택하게 된다. 그러나 개인이 실시간 날씨 정보, 자신의 체감 온도 정보 등을 활용하여 자신이 소장한 의류 중에서 알맞은 의류를 선택하는 것은 어려운 일이다. 이러한 문제를 도와주기 위해 개발된 기존의 의류 추천 시스템들은 의류 범주가 명확하게 설정되어 있지 않고, 사용자가 소지하고 있지 않은 의류를 추천하는 문제점이 있다. 또한 사용자별 체감 온도를 고려하지 않아 사용자에게 적절하지 못한 의류를 추천하는 경우가 발생한다. 이러한 문제점들을 해결하기 위하여 본 연구에서는 사용자가 소장하고 있는 의류에 대해 의류 범주를 결정하여 등록하고, 사용자별 체감 온도와 실시간 날씨 정보를 함께 고려하여 개인별 맞춤형 의류를 추천하는 시스템을 개발하였다. 날씨 정보의 경우, 단순한 기온, 풍향 등의 기상 정보만이 아니라 온도 민감도를 이용하여 개인별 체감 온도에 따른 의류를 추천하였다. 본 시스템을 평가하기 위해 대학생 65명을 대상으로 만족도 조사를 실시하였다. 그 결과 추천된 의류에 대해 만족한다는 의견이 80%를 차지하여 본 시스템의 만족도는 양호한 것을 확인할 수 있었다. 따라서 본 시스템을 사용할 경우, 개인별 체감 온도를 반영하여 개인이 소장한 의류를 기반으로 추천받게 됨으로써 실생활에서 활용도가 매우 높을 것으로 기대된다.

경계요소법을 이용한 압축성형다이 가열선의 최적위치 설계 (Optimal Positioning of Heating Lines in a Compression Molding Die Using the Boundary Element Method)

  • 이부윤;조종래
    • 대한기계학회논문집
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    • 제17권6호
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    • pp.1478-1485
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    • 1993
  • 본 연구에서는 압축 성형다이 가열선의 최적위치를 결정하는 문제를 다이의 형상 최적설계 문제로 정식화하고자 한다. 최적화 문제의 목적은 다이 내면의 온도를 지정된 온도로 균일하게 유지하는 것이다. 또한 Lee, Choi와 Kwak의 형상 설계 민감 도 해석을 위한 직접 미분 방법을 응용하여 가열선 위치변화에 관한 민감도 계산을 위한 경계 적분 방정식을 유도하고, 경계요소법으로 온도와 온도의 민감도를 해석하고 자 한다. 수치적 응용의 예로서, 넓은 평판의 성형을 위한 압축 성형다이의 가열선의 최적위치를 결정하는 문제를 다루고, 최적위치에서 가열선의 개수가 온도의 균일성에 미치는 영향을 검토한다.