• Title/Summary/Keyword: Temperature-humidity Index

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Study on Application of the Preserving Valuation Index for Environmental Management of a Stack Room (서고환경관리를 위한 보존성 평가지수 활용에 관한 연구)

  • Yoon, Dai-Hyun;Shin, Hyun-Chang
    • The Korean Journal of Archival Studies
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    • no.31
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    • pp.139-161
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    • 2012
  • Donald K. Sebera model can quantitatively compare the preserving environment by calculating the preserving valuation index with changing only the temperature and humidity. In this study, Donald K. Sebera model was used in order to compare and evaluate the preserving valuation index on the best condition and the worst condition in the temperature and humidity range of public records management act. As the results, the preserving valuation index in the best conditions was larger 2.47 times than the worst conditions within the preserving environment permitted in public records management act. Also, the influence of the humidity on the preserving valuation index of a paper archives as decreasing the activation energy for the hydrolysis reaction was larger rather than temperature. Thus the preserving valuation index can easily evaluate the suitability of the temperature and humidity conditions for preserving a archives. Therefore it can be used as useful tool for preservation of archives on change of the temperature and humidity.

The Spatial and temporal distributions of NET(Net Effective Temperature) with a Function of Temperature, Humidity and Wind Speed in Korea (한반도의 날씨 스트레스 지수 NET(Net Effective Temperature) 분포의 특성)

  • 허인혜;최영은;권원태
    • Journal of the Korean Geographical Society
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    • v.39 no.1
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    • pp.13-26
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    • 2004
  • This paper examined the possibility of NET application for a relative weather stress index in Korea. The characteristic of NET distribution used temperature, relative humidity, wind speed which forecasting at Korean Meteorological Administration were analyzed. Regional critical values of daily maximum NET of stress index for summer resembled the distribution of daily maximum temperature because were not impacted wind and humidity but temperature. Regional critical values of daily minimum NET of stress index for winter distributed variously compared with summer. The highland region and the northern region of Seoul were impacted of low temperature and coastal region which strong wind. The occurrences of stressful days did not vary in summer, but obviously increased in winter after mid-1990s.

Analyzing Change of Discomfort Index for Transpiration of Street Tree (도시 가로수의 증산 작용으로 인한 불쾌지수 변화 분석)

  • Yun, Seok-Hwan;Lee, Dong-Kun;Park, Chae-Yeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.5
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    • pp.29-43
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    • 2020
  • Thermal environment of city is getting worse due to severe urban heat island caused by climate change and urbanization. The cooling effect of street tree is regarded as a effective way to ameliorate the urban heat environment. The effect is largely made up of shadow formation and transpiration. This study aims to identify how the transpiration affects the discomfort index by analyzing comprehensive impact of the transpiration on the air temperature and relative humidity. The changes in the amount of transpiration, air temperature, and relative humidity were estimated for Seogyo-dong area which has a lot of floating population in Seoul, at 2 p.m. in dry day in July and August. On average, the transpiration of the street tree decreased the temperature 0.3℃ and increased the relative humidity 2.6% in an hour. As a result of these changes in temperature and humidity, the discomfort index rose mostly(0.036 on average). It was always get rise especially on the day when the discomfort index was above 80(0.05 on average). However, compared with the significant change in temperature and humidity, the variation of the discomfort index itself was very slight(up to 0.107). Therefore, the effect of transpiration by the street trees might not be effective in the planning to improve the thermal environment(especially on the day when the discomfort index is high). It is necessary to select the species of trees and planting location considering the cooling effect of shade formation synthetically.

A Study on the Characteristics of Perceived Temperature over the Korean Peninsula During 2007 Summer (한반도 2007년 여름철 인지온도 특성 연구)

  • Byon, Jae-Young;Kim, Jeong-Sik;Kim, Ji-Young;Choi, Byoung-Cheol;Choi, Young-Jean;Graetz, Angelika
    • Atmosphere
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    • v.18 no.2
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    • pp.137-146
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    • 2008
  • This study examines one thermal index, perceived temperature (PT), over the Korean Peninsula during 2007 summer. Heat/cold stress has been described using air temperature and humidity for warm seasons and air temperature and wind velocity in the cold conditions, while PT is based on a heat budget model of the human body that considers air temperature, humidity, wind velocity and radiation effect regardless of climates, regions and seasons. PT is higher about $4-5^{\circ}C$ than air temperature in the summer. Humidity increases PT, while wind tends to reduces PT possibly by evaporation of water vapor. The geographical distribution of summer PT indicates that the lowest PT happened in the east central region, with the appearance of the highest PT in the inland of southern region in Korea. Although the latitudinal trend shows that PT decreases northward, inland PT is higher than that of coastal region. Compared to the heat index or the discomfort index that considers air temperature and humidity, PT represents distinctive regional characteristics of thermal comfort. The distribution of PT shows that it may be a useful thermal index for the assessment of thermal comfort or stress region in the Korean Peninsula.

Indoor Environment Control System Utilizing The Internet of Things (사물인터넷을 활용한 실내 환경 제어 시스템)

  • An, Yoon-Jung;Kim, Dong-Hyeok;Lee, Jee-Hyun;Lee, Boong-Joo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.4
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    • pp.645-650
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    • 2017
  • It is a system that controls temperature, humidity and fine-dust to make interior environment more comfortable for modern people who spend 90% of the time in indoor. In an experiment of finding which one of temperature and humidity influence more to discomfort index, for a fixed temperature of 21, discomfort index increased by 0.1 with a 1 change of humidity, and for a fixed humidity of 40, discomfort index increased by 1.2 with a 1 change of temperature. As a result, it was found that the temperature is more influential than the humidity to discomfort index. In an experiment of measuring communicational limitation of Bluetooth, the communication was possible for at most 30 meters without obstacles. With high obstacles like walls or steel bars, it was able to penetrate at most 2 obstacles and maximum distance which it can communicate was 10 meters for just one high molecule obstacle.

Effects of heat stress on body temperature, milk production, and reproduction in dairy cows: a novel idea for monitoring and evaluation of heat stress - A review

  • Liu, Jiangjing;Li, Lanqi;Chen, Xiaoli;Lu, Yongqiang;Wang, Dong
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.9
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    • pp.1332-1339
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    • 2019
  • Heat stress exerts a substantial effect on dairy production. The temperature and humidity index (THI) is widely used to assess heat stress in dairy operations. Herein, we review the effects of high temperature and humidity on body temperature, feed intake, milk production, follicle development, estrous behavior, and pregnancy in dairy cows. Analyses of the effects of THI on dairy production have shown that body temperature is an important physiological parameter in the evaluation of the health state of dairy cows. Although THI is an important environmental index and can help to infer the degree of heat stress, it does not reflect the physiological changes experienced by dairy cows undergoing heat stress. However, the simultaneous measurement of THI and physiological indexes (e.g., body temperature) would be very useful for improving dairy production. The successful development of automatic detection techniques makes it possible to combine THI with other physiological indexes (i.e., body temperature and activity), which could help us to comprehensively evaluate heat stress in dairy cows and provide important technical support to effectively prevent heat stress.

Drawing of Twenty Kinds of State and Process on Psychrometric Chart (습공기선도 상에 20 종류의 상태 및 과정 값의 작도)

  • Kim, Deok-Jin
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.1201-1206
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    • 2008
  • Psychrometric chart displays graphically the thermophysical properties of moist air, so it is very conveniently used in air-conditioning and refrigeration. On general psychrometric chart, there are dry bulb temperature, web bulb temperature, absolute humidity ratio, relative humidity, specific enthalpy, specific volume, sensible heat factor, and enthalpy-humidity difference ratio. However, various state and process values besides aboves can be plotted on psychrometric chart. In this study, we developed the software drawing twenty kinds of lines, that is vapor pressure, mole fraction ratio of vapor, dew point temperature, degree of saturation, density, specific entropy, specific exergy, contact or bypass factor, uncomfort index, discomposition index, predicted mean vote index, predicted percent dissatisfied, and so on. We wish to this software is a help to design, analysis and education.

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Study on Environmental Monitoring in Stack Room for Paper Storage Using the Preservation Index (보존 환경 평가 지수를 이용한 종이 보존 서고 환경 모니터링 연구)

  • Shin, Hyun-Chang;Yoon, Man-Young
    • Journal of the Korean Graphic Arts Communication Society
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    • v.29 no.1
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    • pp.61-74
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    • 2011
  • Critical environmental elements for long term preservation of a paper are temperature, humidity, dust, light, contaminants in air, and mold. Especially, temperature and humidity need special care, because they can not only directly degrade paper but also affect the degradation of the other elements. Therefore methods to monitor variation of temperature and relative humidity were studied. One of the methods was to use preservation index for evaluating preservation environment. Since the evaluation for preservation environment of a stack room investigated firstly by D. K. Sebera, PI(preservation index) and TWPI(Time-Weighted Preservation Index) by IPI is made to evaluate relatively preservation environment in a stack room. T. Padfield developed method which could calculate easy PI and TWPI. In this study, the preservation environment of stack rooms for paper storage in NAK(National Archives Korea) was evaluated by PI and TWPI. PI and TWPI of stack rooms for paper storage in NAK maintained good condition but PI depended on season. Then the preservation environment of stack rooms for paper storage in NAK was required to maintain continuously PI and TWPI regardless of season change.

Change of Refractive Index of Air in X-band due to Atmospheric Humidity, Temperature and Pressure measured by GB-SAR Interferometry (GB-SAR 간섭기법으로 측정된 X-밴드 대기 굴절률의 상대습도, 기온 및 기압에 따른 변화)

  • Lee, Jae-Hee;Lee, Hoon-Yol;Cho, Seong-Jun;Sung, Nak-Hoon;Kim, Kwang-Eun
    • Korean Journal of Remote Sensing
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    • v.27 no.2
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    • pp.163-170
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    • 2011
  • In this paper, we analyzed the phase change of 5-triangular trihedral comer reflectors by using X-band Ground-Based Synthetic Aperture Radar (GB-SAR) system. Each reflector was set as a stationary target at a different distance from the system. We obtained total 123 full-polarization images during 40 hours continuously at 20 minute interval. Results of SAR interferometric analysis showed phase changes of maximum 2 radians and followed similar pattern with atmospheric data. Through a GB-SAR phase formula that includes refractive index in the air, we performed regression analysis for refractive index as a function of atmospheric humidity, temperature and pressure. As a result, refractive index of air in X-band showed relatively high coefficient of determination with humidity and temperature (0.72 and 0.76 on average, respectively) but not so with pressure (0.34). The refractive index of air in X -band changed by 3.14\;{\times}\;10^{-5}$ during the measuring time with a humidity range of 50% ~ 90% and a temperature range of $-1^{\circ}C$ ~ $9^{\circ}C$. We expect that a total expression of refractive index of air including humidity, temperature and pressure can be calculated when more extensive data would be collected at various atmospheric conditions.

Summer season temperature-humidity index threshold for infrared thermography in Hanwoo (Bos taurus coreanae) heifers

  • Kim, Na Yeon;Moon, Sang Ho;Kim, Seong Jin;Kim, Eun Kyung;Oh, Mirae;Tang, Yujiao;Jang, Se Young
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.10
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    • pp.1691-1698
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    • 2020
  • Objective: The study sought to estimate the relationship between body surface temperature (BST) and temperature humidity index (THI) and to present the validity of THI as a heat stress index in the field. Methods: Eight Hanwoo heifers (20 to 32 month) were examined in a field trial, with a space allowance of 10 ㎡ per head. The BST was measured using an infrared thermographic camera. The BST of five body regions (eyes, hindquarters, nose, part of horns, and ears), ambient temperature (AT), and relative humidity (RH) were measured 7 times daily (07, 09, 11, 13, 15, 17, and 19 h) during each season with three replicates. Results: The THI ranged 34.0 to 56.9 during spring (AT, -1.0℃ to 13.4℃), 75.1 to 84.7 during summer (AT, 24.9℃ to 33.6℃), 55.8 to 70.9 during autumn (AT, 13.0℃ to 26.0℃) and 17.5 to 39.2 during winter (AT, -10.4℃ to 1.0℃). In the regression analysis, the coefficient of determination (R2) between THI and BST was 0.88, 0.72, 0.83, 0.86, and 0.85 for the eyes, hindquarters, nose, part of horn, and ears area, respectively. This indicates that BST has a strong correlation with AT and RH. Expression equations were estimated as Y (THI) = 31.54+0.1085X (BST of eyes) and Y (THI) = 30.48+0.1147X (BST of hindquarters) by simple linear regression analysis in this experiment. Conclusion: Consequently, the upper bound for heat stress estimation can be specified ranging from THI of 65 (eyes) to 70 (hindquarters). From this we can expect a precise feeding system for Korean native cattle in the field.