• Title/Summary/Keyword: Temperature and humidity

Search Result 4,319, Processing Time 0.036 seconds

Investigation of Internal Temperature and Relative Humidity of Concrete Immediately After Mix and Placement (양생직후 초기재령의 콘크리트 내부 온도와 상대습도의 측정 및 분석)

  • Park, Cheol-Woo;Park, Young-Hoon;Park, Yong-Gul
    • Proceedings of the KSR Conference
    • /
    • 2008.11b
    • /
    • pp.1065-1068
    • /
    • 2008
  • Concrete is still one most common construction materials even in railway structures. As structures become massive and mega-sized, the importance of early age concrete quality control becomes more significant. Among various factors, relative humidity and temperature are the primary factors governing the early age quality. Temperature raise due to cement hydration causes stress, which can develop to cracking with internal and/or external restraints. Exposure conditions including ambient temperature, humidity and wind also significantly affect the cracking behavior of early age concrete. Among many of studies on the early age concrete behavior, investigation on the variation of temperature and relative humidity internal of concrete is not common. That is in part because the difficulties in measuring the relative humidity and temperature inside the concrete. This study used a digital sensor with an appropriate logger to measure internal temperature and relative humidity. This direct measuring method is expected to provide more reliable and comprehensive data acquisition on the early age behavior of concrete.

  • PDF

NiO(Co0.25Mn0.75)2O3 and BaSrTiO3 thick films on alumina substrate as temperature and humidity ceramic multisensors

  • Oh, Young-Jei;Lee, Deuk-Yong
    • Journal of Sensor Science and Technology
    • /
    • v.18 no.5
    • /
    • pp.343-348
    • /
    • 2009
  • $NiO{\cdot}(Co_{0.25}Mn_{0.75})_2O_3$(Mn-Ni-Co) and $Ba_{0.5}Sr_{0.5}TiO_3$(BST) thick films were screen printed on Pt patterned alumina substrate to investigate the effects of sintering temperature on humidity and temperature sensing properties of ceramic sensors. A raise in sintering temperature increased resistance and B constant of the Mn-Ni-Co temperature sensor. This may have derived from the synergic effects of the reduction in charge carriers caused by the substitution of Co for Mn as well as the formation of microcracks from the difference in thermal expansion coefficients. Dependence of resistance on humidity of the Mn-Ni-Co temperature sensor, however, was not found. BST films sintered at temperatures in the range of $1100^{\circ}C$ to $1150^{\circ}C$ showed excellent humidity sensing properties. The BST humidity sensor was faster in its response than the Mn-Ni-Co temperature sensor. The humidity sensor, however, proved to be unstable under various temperatures, suggesting a need for a temperature stabilizing device. In contrast, the Mn-Ni-Co temperature sensor was stable under humid conditions.

Problem Solving about Practical Engineering Education based on Relationship of Temperature and Humidity in Vehicle (차량 내 온, 습도 관계에 의한 실천공학교육적 문제해결)

  • Kim, Jin-woo;Joo, Kangwo
    • Journal of Practical Engineering Education
    • /
    • v.9 no.2
    • /
    • pp.149-153
    • /
    • 2017
  • Inside the vehicle, temperature and humidity are suddenly changed. Accordingly, HVAC System's temperature control is very complicated. But, clarifying the relationship between temperature and humidity can reduce the control parameters. Therefore, this paper describes the relationship between temperature and humidity in the vehicle and presents a problem solving method in terms of control technologyThe vehicle sensor monitors the factors required for vehicle control and plays a role in enabling optimal control from the obtained information. Of these sensors, the driving environment of the driver is determined by the temperature and humidity inside the vehicle, and the characteristics of the vehicle suddenly change rapidly. Accordingly, HVAC System's temperature control is very complicated. But, clarifying the relationship between temperature and humidity can reduce the control parameters. Therefore, this paper describes the relationship between the temperature and humidity in the vehicle, and presents a method for controlling the temperature and humidity in the vehicle as an example.

Estimation of Thermal Humidity Inside Concrete and Prediction of Carbonation Depth (콘크리트 내부 온습도 추정 및 탄산화 깊이 예측)

  • Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2021.05a
    • /
    • pp.197-198
    • /
    • 2021
  • The temperature and humidity inside concrete affects the depth of carbonation. In this study, the temperature and humidity inside concrete were predicted by the numerical method under the boundary conditions of ambient temperature, humidity, solar radiation, and wind. Using the results of the thermal humidity analysis, diffusion of carbon dioxide and the reaction of cement hydration products were calculated for carbonation depth.

  • PDF

Indoor Neutral Temperature Range using Temperature and Humidity Perception Assessment

  • Yang, Wonyoung
    • KIEAE Journal
    • /
    • v.16 no.5
    • /
    • pp.29-37
    • /
    • 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.

Design Clean Room of Controled Temperature and Humidity using ATmega128 (ATmega128를 이용한 온.습도 자동제어 모형 제작)

  • Kim, Min-Gu;Kuh, Tae-Hoi;Kim, Young-Min;Shim, Saero-Eol;Soh, Dea-Wha
    • Journal of the Speleological Society of Korea
    • /
    • no.77
    • /
    • pp.59-65
    • /
    • 2007
  • Nowaday, our life is closely related to temperature and the humidity. To control the temperature and the humidity have pursued the comfort environment. We develop that form ware is controled temperature and humidity that used the ATmega128. We embody home-automation system to use the ATmega128, temperature sensor, LCD, relay device and peltier device.

Implications of High Temperature and Low Humidity on the Hatching in the Silkworm, Bombyx mori L. Under LD 12 : 12 Condition

  • Reddy P. Lakshminarayana;Naik S. Sankar;Reddy N. Sivarami
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.11 no.2
    • /
    • pp.139-143
    • /
    • 2005
  • The implications of temperature (25, 30 and $35^{\circ}C$) and relative humidity (RH; 60, 70 and $80\%$) on the hatching rhythmicity and hatching parameters (percentage and duration) were studied in the silkworm, Bombyx mori L. under natural photoperiod (LD 12 : 12). Disease free layings (DFLs) of two pure silkworm breeds, Pure Mysore (PM, a multivoltine breed) and $NB_4D_2$ (a bivoltine breed), and their hybrid, $PM{\times}NB_4D_2$ were introduced into the experimental conditions on the $3^{rd}$ day of oviposition till completion of hatching. The hatching rhythm was predominantly diurnal under all temperature and humidity conditions, with peaks just after 'lights-on' phase (6 hrs). Extreme temperature and humidity conditions did not alter the hatching rhythmicity, but prolonged the hatching durations, extending it to the next day, coupled with reduced hatching percentage in PM and $PM{\times}NB_4D_2{\cdot}In\;NB_4D_2$, on the other hand, hatching did not extend to the next day. Hatching percentage in this breed, however, reduced below the economic level under high temperature and low humidity conditions. The high temperature and low humidity together, though did not alter the rhythmicity, seems to exert synergetic effect on the hatching percentage and its duration in the silkworm, B. mori.

EFFECT OF TEMPERATURE AND HUMIDITY ON THE LEAF COLOR AND CHEMICAL COMPONENTS DURING THE YELLOWING STAGE OF FLUE-CURING (황색종 연초 건조중 황변기 온습도차가 잎담배 색상 및 화학성분에 미치는 영향)

  • Hwang, Keon-Joong;Seok, Yeong-Seon;Lee, Han-Seok
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.7 no.2
    • /
    • pp.129-139
    • /
    • 1985
  • cent was carried out to study on the effect of temperature and humidity to chemical tobacco leaves during the yellowing stage. The results were follows : In the condition of high humidity and low temperature, yellowing time was delayed ; leaf color appeared lack clearness. In the higher temperature and the lower humidity during the yellowing stage : total sugar, reducing sugar and malic acid content were increased. Decomposition of nitrogenous components elevated in $38^{\circ}C$, 85%RH. Changes of total nitrogen content correlated with total curing time. Adecrease of linolenic acid with a corresponding increase of chlorogenic acid proceeded in the condition of low temperature and high humidity. In a view of tobacco quality by chemical components, the low temperature and high humidity during the yellowing stage decreased quality of tobacco leaves. It is considered to control of the proper condition of temperature and humidity during the yellowing.

  • 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.).

A Comparison Evaluation on the Indoor Temperature and Humidity Control Effect of Hwang-To Brick and Traditional Window as Exterior envelops in Mock-up Room (Mock-up 실험을 통한 황토벽과 전통창호의 실내 온습도 조절효과에 대한 비교평가)

  • Song, Min-Jeong;Shin, Hoon
    • KIEAE Journal
    • /
    • v.10 no.6
    • /
    • pp.131-137
    • /
    • 2010
  • This study aims to know temperature and humidity handling ability of Hwang-To brick and traditional paper window's in mock-up room test. To achieve these goals, mock-up room test was carried out. The results are as follows. 1) There are no significant differences among specimen in temperature handling capacity. 2) Traditional paper windows are very sensitive when compared with glass window in humidity control. 3) Traditional paper windows have a big handling capacity in humidity control when vapors letting out in mock-up room. 4) Hwang-To brick case is more stable than other cases in relative humidity variances because it has more potential to contain humidity.