• Journal of Sensor Science and Technology
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• v.6 no.1
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• pp.43-48
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• 1997

$Ca_{10}(PO_{4})_{6}(OH)_{2}$ humidity-sensitive devices were fabricated by a solid reaction method, and their humidity-sensitive characteristics were investigated. The impedance decreases with increasing relative humidity, and the good sensitivity is shown in which impedance changes by about $10^{2}\;{\Omega}$ over the region of $30{\sim}90\;%$. Also, It is shown that the humidity sensitivity is stable in temperature variations and long time exposures to the humidity. The sensitivity of the specimens is not affected by a heat treatment, and the hysteresis in one humidity cycle is negligible.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1227-1232
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• 2014

The purpose of this paper is to establish the optimum fabricating condition of specimens using silk screen printing, and to develop humidity sensor which has good humidity sensing properties. The specimens are fabricated under the condition of 90[wt%] $SnO_2$-10[wt%] $TiO_2$, and their microstructure, crystalline structure, humidity sensing properties are examined. From the microstructure analyses, porosity is best at 700[$^{\circ}C$]. From the crystalline structure analyses, intensity of peak becomes strong according to increasing heat treatment temperature. From the humidity sensing properties analyses, an overall results of capacitance changes, linearity and hysteresis for the specimens is best at 600[$^{\circ}C$] and 700[$^{\circ}C$]. Capacitance of specimens increases according to decreasing measurement frequency, and to increasing relative humidity.

• Korean Journal of Optics and Photonics
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• v.24 no.5
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• pp.251-255
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• 2013

In this paper, the characteristics of a humidity sensor implemented by Mach Zehnder Interferometer (MZI) in a Planar Lightwave Circuit (PLC) have been designed and demonstrated. The humidity outside is detected with polyvinylpyrrolidone (PVP) coated on the etched arm of the MZI. The length of the etched arm is 10 mm and the PVP was coated by dip-coating into the etched region. As the refractive index of the PVP changes with the surrounding humidity, the PVP-coated humidity sensor presented changes in the interferogram depending on RH (Relative Humidity) around the PLC. The measured results show that the proposed humidity sensor works successfully in the range of 30% to 80% of RH.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.2
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• pp.185-190
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• 2015

This paper presents a new method to determine sensitivity coefficients of temperature and humidity of torque transducers by using a natural and seasonal variation of ambient conditions at the laboratory. We had measured the sensitivities of the torque transducers over almost one year using the KRISS 2 kN m torque standard machine. The sensitivity data acquired at various ambient conditions were processed using our measurement model to extract the sensitivity coefficients of temperature and humidity simultaneously with high precision. A comparison with a previous method using an environmental control chamber was carried out to test the feasibility of using our new method. Two results agreed within the uncertainty. We revealed that the torque measuring errors could be 8 times higher than the measurement and calibration capability of KRISS torque standard machine if the sensitivity changes due to the temperature and humidity are not properly corrected during a calibration.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.247-248
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• 2006

Carbon nitride films were evaluated that they had many advantages for miniature micro-humidity-sensors using the standard CMOS technology humidity sensing properties and CV characteristics of the carbon nitride films have been investigated for fabricating one chip HUSFET(Humidity Sensitive Field Effect Transistor) humidity sensors Carbon nitride films were deposited on silicon substrate with meshed electrodes by reactive RF magnetron sputtering system. The capacitor-type humidity sensor revealed good humidity-impedance characteristics with a wide range of relative humidity changes, decreasing $254k{\Omega}$ to $16k{\Omega}$ according to increase of relative humidity between 5% ~ 95% and the films were very stable on the Si wafer. These results reveal that $CN_x$ thin films can be used for Si based or HUSFET structure one chip micro-humidity sensors.

• Advances in concrete construction
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• v.9 no.5
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• pp.459-467
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• 2020

Mechanical and thermal properties of composite sandwich wall panels are affected by changes in their external environment. Humidity and temperature changes induce stress on wall panels and their core connectors. Under the action of ambient temperature, temperature on the outer layer of the wall panel changes greatly, while that on the inner layer only changes slightly. As a result, stress concentration exists at the intersection of the connector and the wall blade. In this paper, temperature field and stress field distribution of UHPC-RW-RC (Ultra-High Performance Concrete - Rock Wool - Reinforced Concrete) wall panel under high temperature-sprinkling and heating-freezing conditions were investigated by using the general finite element software ABAQUS. Additionally, design of the connection between the wall panel and the main structure is proposed. Findings may serve as a scientific reference for design of high performance composite sandwich wall panels.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.113-117
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• 1994

In this paper, an experiment about humidity sensing properties of oxide aluminum films by Anodic oxidation method was made. The humidity sensing properties of films were investigated in the relative humidity range of 10∼85(%RH) , changing the frequency from 1[kHz] to 100[kHz]. The impedance of humidity sensing films were decreased in accordance with the increase of relative humidity. The decreasing rate of impedance were larger at low measuring frequency. The decreasing difference changes from 17.7M$\Omega$ to 3.68M$\Omega$ at low measuring frequency.

• KIEAE Journal
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• v.16 no.5
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• pp.29-37
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• 2016

Purpose: Indoor thermal comfort can be identified by combination of temperature, humidity, and air flow, etc. However, most thermal indexes in regard to thermal comfort are temperature dominant since it has been considered as a significant factor affecting to indoor thermal comfort The purposes of this study are to investigate indoor neutral temperature range of young Koreans with humidity perception, and to introduce a neutral temperature for temperature preference as well as temperature sensation in order to define the neutral temperature range chosen by occupants. It could be used as basic data for heating and cooling. Method: 26 research participants volunteered in 7 thermal conditions ($18^{\circ}C$ RH 30%, $18^{\circ}C$ RH 60%, $24^{\circ}C$ RH 30%, $24^{\circ}C$ RH 40%, $24^{\circ}C$ RH 60%, $30^{\circ}C$ RH 30%, $30^{\circ}C$ RH 60%) and completed subjective assessment in regard to temperature/humidity sensation and preference twice per condition in an indoor environmental chamber. Result: In RH 30%, sensation neutral temperature was $25.1^{\circ}C$ for men and $27.0^{\circ}C$ for women, and preference neutral temperature was $25.5^{\circ}C$ for men and $27.8^{\circ}C$ for women. In RH 60%, sensation neutral temperature was $23.6^{\circ}C$ for men and $25.9^{\circ}C$ for women, and preference neutral temperature was $23.4^{\circ}C$ for men and $26.3^{\circ}C$ for women. Neutral temperature increased with increasing relative humidity. Women were sensitive to humidity changes. Men expressed humidity changes as temperature variations. In most conditions, preference neutral temperatures were higher than sensation neutral temperatures, however, the preference neutral temperature for men in humid condition was lower than the sensation neutral temperature.

• Fashion & Textile Research Journal
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• v.2 no.3
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• pp.220-226
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• 2000

This study was to determine the characteristics of vapor-permeable waterproof finished fabric by the coating method. 4 different kinds of coating fabrics (A : wet, porous, polyurethane, B : dry, no porous, polyurethane, C : shape memory polyurethane and D : dry, porous polyurethane) were used, which were developed recently With this sample, moisture transport rate ($40^{\circ}C$, 45%RH & $40^{\circ}C$, 95%RH), changes of coating side's shape by washing times, water repellency rate, contracted length, qmax, heat conductivity, heat keeping rate, heat keeping rate with cotton, heat keeping rate on humidity temperature and humidity within clothing etc. were checked. And it was done in a climate chamber under $20{\pm}2^{\circ}C$, $65{\pm}5%RH$. The results of this study were as follow; In the moisture vapor transmission of sample B and C increased on high temperature and high humidity while sample A and D decreased, on this condition. Qmax rate had high relation with ground fabric's surface properties and the order was A>C>D>B. Heat conductivity had high relation with thickness and surface properties. Heat keeping rates on sweat condition showed around half percents of heat keeping rates on normal condition, but had no relation with moisture vapor transport rate. Changes of the fabric's properties by washing times were different in accordance with the construction of fabrics and the coating resin. Sample C had tow heat keeping rate on the high temperature and humidity and high heat keeping rate on the low temperature and humidity Moisture transport rate of vapor-permeable waterproof finished fabrics had high relation with the properties of ground fabrics on low humidity condition, but on the high humidity condition, it was highly related with the properties of coating resin.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.300-304
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• 2000

Tuberous roots of yacon (Polymnia sonchifolia Poeppig ＆ Endlicher) were stored in different temperature and relative humidity conditions after curing for 30 days. Non-decadent percentage, moisture contents, brix degree and sugars were investigated. Whether temperature and relative humidity were high or not, most of the tuberous root decayed during storage, and the decayed percentage was increased as long as the storage period. In final, only 13% of tuberous roots remain intact at 4$^{\circ}C$, 85% relative humidity condition to be appeared best storage condition in this experiment and all of the tuberous root decayed in other storage conditions after 6 months. Moisture contents decreased a little in the high relative humidity. Even though tuberous roots decayed when stored at 1$0^{\circ}C$ and 2$0^{\circ}C$, most of brix degree reached about 17.0. Fructose, glucose and sucrose contents were 1.65, 1.15 and 0.35% at early storage period, and 1.6, 1.1 and 0.5% after 6 months at 4$^{\circ}C$, 85% relative humidity, respectively. In 3 temperature conditions, fructose and glucose increased for a month and then decreased successively afterwards, but sucrose increased gradually during 6 months. Also in 4 relative humidity conditions, fructose, glucose and sucrose contents were changed with similar to that of in temperature. Changes of fructose and glucose were the same except on 4$^{\circ}C$, 85% relative humidity, that was lower level than moisture of tuberous root.