• Title/Summary/Keyword: Environment humidity

Search Result 1,651, Processing Time 0.02 seconds

Evaluation of DC Resistive Humidity Sensors Based on Conductive Carbon Ink (전도성 카본 잉크를 이용한 직류 저항형 습도센서 제작 및 평가)

  • An, Taechang
    • Journal of Sensor Science and Technology
    • /
    • v.26 no.6
    • /
    • pp.397-401
    • /
    • 2017
  • A DC resistance type humidity sensor using conductive carbon ink was fabricated and its performance was evaluated. The humidity sensor was fabricated using a screen printing technique and have a structure that does not require additional metal electrodes to measure resistance change. To evaluate the performance of the humidity sensor, we measured the DC resistance change under various relative humidity levels. The fabricated humidity sensor showed a resistance change of about $2.5{\sim}50k{\Omega}$ in 11 ~ 95% RH environment. It also shows a linear relationship in the relative humidity versus log DC resistance graph. In comparison with commercial humidity sensor under real environment, it can be confirmed that the resistance of the humidity sensor changes to almost the same level as the measured humidity. These results show that the resistance type humidity sensor can be operated stably in actual environment.

Electrostatic Electrification Properties of Polypropylene Film due to Elongation Transition (신장율 변화에 의한 폴리프로필렌 필름의 정전기 대전 특성)

  • Lee, Sung-Ill;Kim, Sang-Hyeon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.23 no.1
    • /
    • pp.48-52
    • /
    • 2010
  • This paper examined the effects of specimen elongation on the electrostatic electrification voltages when polypropylene film specimens with 500%, 650% and 700% elongations were rotated at 1550 rpm. The results were as follows. The decease of electrification voltage was not measured according to the time elapse, in case of elongated specimens with 70% environment humidity. As +10 kV was applied to the specimens with 650% elongations, the electrostatic electrification voltages were increased by the effect of environment humidity (1.23~1,25 kV at 50~60% humidity, and 1,46 kV at 70% humidity). The voltages were decreased to 1.2 kV at 700% elongation. As -10 kV was applied to the specimens with 500%, 650% and 700% elongations, the electrostatic electrification voltages were negatively increased with the increase of environment humidity and the elongation of specimens.

Effects of Long-term Exposure of High and Low Humidity on Thin-film Humidity Sensors

  • Lee, Sang-Wook;Choi, Byung Il;Kim, Jong Chul;Woo, Sang-Bong
    • Journal of Sensor Science and Technology
    • /
    • v.27 no.6
    • /
    • pp.368-373
    • /
    • 2018
  • The effects of long-term exposure of high and low humidity on thin-film humidity sensors are investigated. Five commercially available thin-film humidity sensors are initially calibrated in a humidity chamber as a reference before longterm exposure to high and low humidity. Then, the sensors are kept in a high-humidity environment (~95 %rh) for four months. After the exposure, the sensors are calibrated in the same manner as the initial calibration. Consequently, the device reading values from the humidity sensors are elevated up to about 5 %rh. Interestingly, the degree of elevation by the high-humidity exposure shows a negative correlation with the price of the humidity sensors. Humidity sensors are then kept in a low-humidity environment (~10 %rh) for another four months. After the exposure, a calibration similar to the initial calibration is performed. As a result, the device reading from humidity sensors is decreased, indicating a recovery from the effect of high-humidity exposure. The durability test conducted in this study provides experimental evidence for the use of thin-film humidity sensors in high-humidity environments such as greenhouses and food factories for a long period of time.

The Effect of Plants and Waterscape Facilities on the Thermal Indoor Environment (실내에서 식물과 수경시설이 온열환경에 미치는 영향)

  • 정연승;박인환
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.27 no.1
    • /
    • pp.19-28
    • /
    • 1999
  • This survey is to investigate the effect of plants and waterscape facilities on the thermal indoor environment and to provide basic data for proper plant cultivation to enhance indoor landscape. The survey of the measure of comfort on the indoor environment for the residents of Taegu shows that the measure of comfort on the thermal-environment, which consist of temperature and humidity, has more negative responses than the measure on lighting . are . sound environment, which consists of air freshness, lighting condition and sound environment. The experiments on the effect of the amount of leaves and the distance of plants on the indoor thermal-environment are made. The experimental results illustrate that, as the capacity of a plant becomes greater and the distance from the plant shorter, the falling effect of temperature and the rising effect of humidity on the top of the plant are taken higher than on the side of the plant. When the same amount of leaves is set up, the distance range of the rising effect of humidity becomes wider than that of the falling effect of temperature. The investigation of the effect of waterscape facilities on the indoor thermal-environment shows that temperature and humidity of the space with installed waterscape facilities are lower and higher than without facilities, respectively.

  • PDF

Analysis of Housing Environment in Semi Basement Multi-family Housing Units - Focuses on long-term analyzed measurements of temperature and humidity obtained from the housing units - (다가구 주택 반지하세대의 주거환경 분석 - 장기 온·습도 모니터링 분석을 통한 실측결과를 중심으로 -)

  • Jang, Kun-Young;Ryu, Dong-Woo
    • Journal of the Architectural Institute of Korea Structure & Construction
    • /
    • v.34 no.2
    • /
    • pp.83-90
    • /
    • 2018
  • This study was conducted to investigate the living environment of semi-basement housing units in multi-household houses. It analyzed measurements of temperature and humidity obtained from the housing units. For this study, temperature and humidity sensors were installed in 10 semi-basement housing units to measure interior temperature and humidity for 13 months. A survey was conducted to get information about the occurrence of dew condensation and mildew and to investigate residents' satisfaction level with the residential environment. According to the result, all the housing units under study had dew condensation and mildew. The average summer temperature of the 10 housing units was $27.84^{\circ}C$, and average humidity was 64.91%RH, while the average winter temperature was $20.6^{\circ}C$, and the average humidity was 40.12%RH. Depending on the condition of each housing unit, deviation was big. Residents' average level of satisfaction with the living condition was 2.03 which shows a low satisfaction (on a scale of 1-5 with 5 being completely satisfied.).

Optimization of Several Environmental Factors to Human Performance by Using Taguchi Method

  • Ismail, A.R.;Haniff, M.H.M.;Yusof, M.Y.M.;Rahman, M.N.A.;Ghani, J.A.
    • Industrial Engineering and Management Systems
    • /
    • v.9 no.2
    • /
    • pp.157-164
    • /
    • 2010
  • The objective of this study is to determine the dominance effects of environmental factors such as Illuminance, humidity and Wet Bulb Globe Temperature (WBGT) on the operators' productivity at Malaysian electronic industry. A case study was carried out at an electronic components assembly factory. The environmental factors examined were the Illuminance (lux), humidity and WBGT of the surrounding workstation area. Two sets of representative data including the illuminance, humidity and WBGT level and production rate were collected during the study. The production rate data were collected through observations and survey questionnaires while the illuminance level was measured using photometer model RS 180-7133, the humidity and WBGT level were measured by using Quest Temp apparatus and humidity. Taguchi Method was utilized to find the sequence of dominant factors that contributed to the productivity of operator at that specified production workstation. The study reveals that the dominant factor contributed to the productivity was WBGT, followed by illuminance and humidity.

Effect of humidity on postmortem changes in rats

  • Seroc Oh;Byeongwoo Ahn;Beom Jun Lee;Sang-Yoon Nam
    • Journal of Veterinary Science
    • /
    • v.25 no.3
    • /
    • pp.24.1-24.9
    • /
    • 2024
  • Importance: In veterinary forensic science, accurately determining the postmortem interval (PMI) is crucial for identifying the causes of animal deaths. Autolysis, a significant postmortem process, influences PMI estimation, but its relationship with humidity is not well understood. Objective: This study aimed to improve the accuracy of PMI estimates in veterinary forensic cases by looking into how different humidity levels affect autolysis in different organs of rats. Methods: The study involved 38 male rats, examining histopathological changes in their heart, liver, and pancreas. These organs were subjected to controlled humidity levels (20%, 55%, and 80%) at a constant 22℃. Tissue samples were collected at several intervals (0 h, 12 h, 24 h, 3 days, and 8 days) for comprehensive analysis. Results: Distinct autolytic characteristics in animal organs emerged under varying humidity conditions. The low-humidity environment rapidly activated autolysis more than the high-humidity environment. In addition, it was found that lower humidity caused nuclear pyknosis, cytoplasmic disintegration, and myofiber interruption. The liver, in particular, showed portal triad aggregation and hepatocyte individuation. The pancreas experienced cell fragmentation and an enlarged intracellular space. High humidity also caused the loss of striations in cardiac tissues, and the liver showed vacuolation. Under these conditions, the pancreas changed eosinophilic secretory granules. Conclusions and Relevance: The study successfully established a clear connection between the autolytic process in PMIs and relative humidity. These findings are significant for developing a more accurate and predictable method for PMI estimation in the field of veterinary forensic science.

A study on humidity control characteristics of inorganic paint (무기질 도료의 조습성능에 관한 연구)

  • Heo, Jung-Yong;Choi, Chang-ho;Lee, Yun-Gyu
    • Proceedings of the SAREK Conference
    • /
    • 2008.06a
    • /
    • pp.1225-1230
    • /
    • 2008
  • Recently the building material have been developed with the concept of controlling the indoor environment as well as the concept of emitting contaminants less. So, a lot of products with humidity control characteristics put it on the market. However, objective evaluation to these products doesn't work out. Thus consumers cannot obtain accurate information to these products. Therefore, we selected inorganic paint in the functionality materials and evaluated its humidity control characteristic in this research. We divided by four stages and evaluated this inorganic paint. The 1st and 2nd third experiments were executed on a natural condition and the fourth experiment was executed with humidity had been raised by using the humidifier.

  • PDF

Characterization of Indoor Temperature and Humidity in Low-income Residences over a Year in Seoul, Korea

  • Lee, Daeyeop;Lee, Kiyoung;Bae, Hyunjoo
    • Asian Journal of Atmospheric Environment
    • /
    • v.11 no.3
    • /
    • pp.184-193
    • /
    • 2017
  • People spend the majority of their time in indoor environments. Maintaining adequate indoor temperature and humidity is necessary to support health and improve quality of life. However, people with low incomes can be vulnerable because they may not be able to use effective cooling and heating systems in their homes. In this study, the indoor temperature and humidity in low-income residences over a year in Seoul, Korea was characterized. Indoor temperature and humidity were measured in three types of homes (12 rooftop residences, 16 basement residences, and 18 public rental apartments) occupied by low-income residents. Both differed significantly among the three types of residence, particularly during the summer and winter seasons. A regression model between indoor and outdoor temperature detected a heating threshold at $3.9^{\circ}C$ for rooftop residences, $9.9^{\circ}C$ for basement residences, and $17.1^{\circ}C$ for public rental apartments. During tropical nights and cold-wave advisory days, rooftop residences showed the most extreme indoor temperatures. This study demonstrates that people living in rooftop residences could be at risk from extreme hot and cold conditions.

Characteristics of Meteorological Environment Variation Before and After Construction of Nak-dong River Estuary Barrage (낙동강 하구둑 건설 전·후의 기상환경 변화 특성)

  • Jeon, Byung-Il
    • Journal of Environmental Impact Assessment
    • /
    • v.14 no.3
    • /
    • pp.135-145
    • /
    • 2005
  • This study was conducted to investigate the characteristics of meteorological environment variation before and after construction of Nak-dong river estuary barrage. We used meteorological data(air temperature, precipitation, relative humidity, visibility, wind) at Gimhae airport meteorological station. The construction of river estuary barrage can change climate at the neighboring districts and influence human's health and vegetable. The construction of Nakdong river estuary barrage brought rise of temperature, decrease of relative humidity and increase of poor visibility frequency.