• Title, Summary, Keyword: Temperature change

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The Change of Superficial and Deep Heats in Ultrasound Application by Coupling Media (초음파 적용시 전파매질에 따른 표면열과 심부열의 변화)

  • Lee, Young-Hi;Kim, Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.12 no.2
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    • pp.57-67
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    • 2000
  • The purpose of this study was carried out in five rabbits of 3kg to investigate the change of superficial and deep heats in ultrasound application by coupling media. Temperature measured with thermistor needle at skin. subcutaneous, muscle in before coupling media application, after coupling media application. 2minutes. 5minutes, 7minutes, 10minutes. Coupling media was used gel, glycerin, distilled water. The data was analyzed using spss/pc+and t-test The results were as fallow : 1. With skin. gel was significant temperature change in 2minutes(p<.05). glycerin was significant temperature change in 2minutes(p<.05), 5minutes(p<.05), 7minutes(p<.01), 10minutes(p<.01). distilled water was significant temperature change in post coupling media(p<.05), 2minutes(p<.01). 5minutes(p<.05). 7minutes(p<.01). 10minutes(p<.01). With subcutaneous. gel was no temperature change. glycerin was significant temperature change in 2minutes(p<.05), 5minutes(p<.05), 10minutes(p<.01). distilled water was no temperature change. With muscle. gel was no temperature change. glycerin was significant temperature change in 2minutes(p<.05). 5minutes(p<.05). 7minutes(p<.05). 10minutes( p<.05). distilled water was significant temperature change in 10minutes(p<.05). 2. Superficial heats of skin and subcutaneous was higher temperature change than Deep heats of muscle. 3. Gel. glycerin. distilled Water required minimum treatment 10minutes fur thermal effect. 4. Gel was low temperature change superficial and deep heats. and glycerin was high temperature change superficial and deep heats. This results show that gel is high transmissiveness in the coupling media and glycerin is low transmissiveness in the coupling media.

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The Development of the Temperature Compensation Equipment to minimize Error in the Wireless Transmission System at 60GHz Band (60GHz대역 무선통신장애 해결을 위한 온도보상장치 개발)

  • Myung, Byung-Soo;Ku, Seong-Deag
    • Journal of the Korean Society of Industry Convergence
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    • v.8 no.2
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    • pp.97-104
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    • 2005
  • Usually, propagation attenuation of millimeter wave occurs by rainfall, snowfall, temperature, effect of pressure of air. In 60GHz wave band wireless communication network, temperature change becomes big factor of propagation loss department. Also, temperature change causes disturbance of 60GHz frequency at transceiver. In this study, we used 60GHz transceiver and found propagation loss of wireless path and operating frequency disturbance characteristics. In transceiver that there is no temperature compensated device, operating frequency of TX changed by 60.865GHz at temperature of $-5^{\circ}C$, and appeared by 60.730GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 100MHz, greatly. But, in transceiver that there is temperature compensated device, operating frequency of TX changed by 60.830GHz at temperature of $-5^{\circ}C$, and appeared by 60.710GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 20MHz. According to these result, we constructed between buildings examination wireless site for point to point wireless communication using 60GHz band transceivers who have do temperature compensated device, and investigated data transmission characteristics about ambient temperature change. Therefore, if use transceiver that have temperature compensated device, may overcome the wireless transmission error in 60GHz band wireless communication LAN networks despite of ambient temperature change.

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Analysis about CO Diffusion Change Caused by Climate Change Using CALPUFF (CALPUFF 모델을 이용한 기후변화에 따른 일산화탄소의 대기오염 영향 분석)

  • Ha, Minjin;Lee, Taekyeong;Lee, Im Hack;Jeon, Eui Chan
    • Journal of Climate Change Research
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    • v.8 no.2
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    • pp.81-89
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    • 2017
  • In this study CALPUFF was used to estimate the influence of temperature rise, according to the observation value of temperature rise based RCP scenario, on meteorological elements (wind direction, wind speed, mixing height) and the change of pollutant diffusion. According to the result. applying estimated value of year 2050 temperature rise, the mixing height is increased as per the temperature rise, so the range of atmospheric diffusion is widened. In summer case, by applying temperature rise of $4^{\circ}C$ and comparing with before applying temperature rise, there was change of diffusion range as per the change of temperature between 10 AM to 11 PM. And the range of diffusion was wider than that of before temperature rise. In winter case, by applying estimated value of temperature rise, $2.3^{\circ}C$, diffusion range has been changed between 8 AM to 4 PM, showing different diffusion aspect from summer. Also, according to the result of air pollution level assessment with temperature rise, it was proved that the ratio of area with increasing air pollution level has been getting higher by increase of temperature.

Projected Climate Change Impact on Surface Water Temperature in Korea (기후변화에 따른 지표수의 수온 영향평가)

  • Ahn, Jong Ho;Han, Dae Ho
    • Journal of Korean Society on Water Environment
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    • v.26 no.1
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    • pp.133-139
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    • 2010
  • Global human activities associated with the use of fossil fuels have aggravated climate change, increasing air temperature. Consequently, climate change has the potential to alter surface water temperature with significant impacts on biogeochemical cycling and ecosystems in natural water body. In this study, we examined temporal trends on historical records of surface water temperature, and investigated the air temperature/water temperature relationship and the potential water temperature change from an air temperature scenario developed with regional climate model. Although the temporal trends of water temperature are highly variable site-by-site, surface water temperature was highly dependent on air temperature, and has increased significantly in some sub-watersheds over the last two decades. The results presented here demonstrate that water temperature changes are expected to be slightly higher in river system than reservoir systems and more significant during winter than summer for both river and reservoir system. Projected change of surface water temperature will likely increase $1.06^{\circ}C$ for rivers and $0.95^{\circ}C$ for reservoirs during the period 2008 to 2050. Given the potential climatic changes, every $1^{\circ}C$ increase in water temperature could cause dissolved oxygen levels to fall every 0.206 ppm.

Analysis of Decompression Control Characteristics of Pneumatic Pressure Control System Considering Heat Transfer Characteristics (열전달 특성을 고려한 공기압 압력제어계의 감압제어특성 해석)

  • Jang, J.S.
    • Journal of the Korea Society For Power System Engineering
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    • v.10 no.1
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    • pp.90-95
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    • 2006
  • Pneumatic control systems have been mainly used as a high speed operating system. Therefore, state change of air in a control volume was assumed to be adiabatic change and, pneumatic control systems have been analyzed by using this assumption. Especially, when absolute value of pressure change in the control volume is small, there is a tendency to neglect effect of temperature change on pneumatic control system because temperature change owing to pressure change is small. In this study, an effect of temperature change of air on the decompression control process was analyzed by considering change of mass flow rate, and heat transfer characteristics between air in the chamber and the chamber wall. As a result, this study could confirm that a slight temperature change of the air in the pneumatic pressure control system can influence on the dynamic characteristics of pressure response, and pressure control performance.

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Change of Surface Temperature in Woodceramics Made from MDF(I) -Effect of Density and Burning Temperature- (MDF로 제조된 우드세라믹의 표면온도변화(I) -밀도 및 소성온도의 영향-)

  • 오승원
    • Journal of Korea Foresty Energy
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    • v.21 no.1
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    • pp.1-6
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    • 2002
  • The following conclusions were obtained with measuring the surface temperature change of woodceramics which were made of MDF to identify usability of using them as a sub-material for heating system when installing Ondol heating floor. For this purpose, woodceramics were burned at the temperature of $650^{\circ}C$ and $800^{\circ}C$ 1. Surface temperature of woodceramics increased with the increase of density of woodceramics, but no significant difference was detected at the surface temperature when burning temperature was changed. 2. Surface temperature change under given temperature increased as time passed and it showed more increase in temperature at the burning temperature of 80$0^{\circ}C$. 3. Surface temperature change with the change in floor temperature increased u hen floor temperature increased and heating mechanism was fast with increase of measuring temperature.

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Accuracy Comparison of Air Temperature Estimation using Spatial Interpolation Methods according to Application of Temperature Lapse Rate Effect (기온감률 효과 적용에 따른 공간내삽기법의 기온 추정 정확도 비교)

  • Kim, Yong Seok;Shim, Kyo Moon;Jung, Myung Pyo;Choi, In Tae
    • Journal of Climate Change Research
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    • v.5 no.4
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    • pp.323-329
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    • 2014
  • Since the terrain of Korea is complex, micro- as well as meso-climate variability is extreme by locations in Korea. In particular, air temperature of agricultural fields is influenced by topographic features of the surroundings making accurate interpolation of regional meteorological data from point-measured data. This study was carried out to compare spatial interpolation methods to estimate air temperature in agricultural fields surrounded by rugged terrains in South Korea. Four spatial interpolation methods including Inverse Distance Weighting (IDW), Spline, Ordinary Kriging (with the temperature lapse rate) and Cokriging were tested to estimate monthly air temperature of unobserved stations. Monthly measured data sets (minimum and maximum air temperature) from 588 automatic weather system(AWS) locations in South Korea were used to generate the gridded air temperature surface. As the result, temperature lapse rate improved accuracy of all of interpolation methods, especially, spline showed the lowest RMSE of spatial interpolation methods in both maximum and minimum air temperature estimation.

The Trend on the Change of the Cherry Blossom Flowering Time due to the Temperature Change (기온 변화에 따른 벚꽃 개화시기의 변화 경향)

  • Lee, Seungho;Lee, Kyoungmi
    • Journal of Environmental Impact Assessment
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    • v.12 no.1
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    • pp.45-54
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    • 2003
  • The purpose of this paper is to examine the trend on the change of the cherry blossom flowering time due to the temperature change by selecting regions that have long periods of cherry blossom flowering time data as cases. With the flowering time data, the distribution of cherry blossom flowering time, time series change and change rate of cherry blossom flowering time were analyzed. Also, the correlation between the cherry blossom flowering time and the temperature was analyzed. The flowering of cherry blossom is earlier in metropolitan areas, and in the east coastal region than the west coastal region. The trend on the change of the cherry blossom flowering time is very similar to change the temperature. The change rate of the cherry blossom flowering time is rising up in the whole regions under study, and is relatively high in metropolitan areas. Especially, the cherry blossom flowering time festinated greatly in Pohang that is one of the heavily industrialized cities. From the analysis of correlation analysis between cherry blossom flowering time and temperature elements, the cherry blossom flowering time is highly related with mean temperature of March, which the month is just before the beginning of flowering.

Modal Parameter variation of Steel Cable-stayed Bridge Considering Solar Radiation (일사에 의한 온도변화에 따른 강사장교의 동적특성 변화)

  • Kim Sang-Hyo;Jo Kwang-Il;Park Ju-Yang
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • pp.1040-1047
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    • 2006
  • Bridges are exposed to constantly changing weather conditions and temperature. The temperature change is induced by a change in atmospheric temperature and solar radiation. Atmospheric temperature change acts on the whole structure. Thus, it is relatively easy to consider in the design. Solar radiation, however, causes un-uniform temperature distribution in the structure, depending on the shape of the structure and its shadows. Un-uniform temperature distribution causes a torsional moment in bridge section and a deformation of bridge. A deformation can make differences of dynamic and static behavior of bridge. In this study, the method for analysis of static and dynamic behavior considering deformation and changes of material properties due to temperature variation was developed. By this method, it is found from dynamic analysis results that the change of frequency in analysis model is similar with test results of public used cable-stayed bridge. When a temperature goes down, a frequency goes up. And it is found that the change of frequency is affected by the change of material properties.

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The Study of Pressurant Inflow Prediction Using Temperature Change of Geostationary Satellite Propellant System (정지궤도 인공위성 추진시스템의 온도변화를 통한 배관내 가압제 유입 예측기법 연구)

  • Park Eung Sik;Jun Hyoung Yoll;Park Bong Kyu;Han Cho Young;Choi Seong Bong;Kim Yong Min
    • 한국전산유체공학회:학술대회논문집
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    • pp.96-99
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    • 2005
  • The geostationary satellite propulsion system has thermistors which can measure liquid propellant temperature at tanks, pipes and etc. In the satellite propulsion system with several tanks, the propellant in the tanks is moved by temperature change and this temperature pattern is constant. In this paper, the temperature change pattern of KOREASAT 1 propulsion system is compared and the prediction study of pressurant inflow using temperature change of geostationary satellite propulsion system is described.

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