• 동의생리병리학회지
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• 제16권5호
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• pp.1035-1041
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• 2002

Ultrasonic nebulizer with the application of new engineering methodology and the design of electronic circuit and 766ppm Cd nebulizing solution were used to generate cadmium aerosol for inhalation toxicology study. The results of particle size analysis for cadmium aerosol were as following. The highest particle counting for source temperature 20℃ was 43.449 x 10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 50℃ was 43.211 x 10³ in inlet temperature 100 ℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 70℃ was 41.917x10³ in inlet temperature 250℃ and particle diameter 0.75㎛. The ranges of geometric mean diameter(GMD) were 0.677-1.009㎛ in source temperature 20℃, 0.716-0.963㎛ in source temperature 50℃, and 0.724-0.957㎛ in source temperature 70℃. The smallest GMD was 0.677㎛ in source temperature 20℃ and inlet temperature 20℃. and the largest GMD was 1.009㎛ in source temperature 20℃ and inlet temperature 20℃. The ranges of geometric standard deviation(GSD) were 1.635-2.101 in source temperature 20℃. 1.676-2.073 in source temperature 50℃, and 1.687-2.051 in source temperature 70℃. The lowest GSD was 1.635 in source temperature 20℃ and inlet temperature 20℃, and the highest GSD was 2.101 in source temperature 20℃ and inlet temperature 200℃. Aerosol generated for cadmium inhalation toxicology study was polydisperse aerosol. The ranges of mass median diameter(MMD) were 1.399-5.270㎛ in source temperature 20℃. 1.593-4.742㎛ in source temperature 50℃, and 1.644-4.504㎛ in source temperature 70℃. The smallest MMD was 1.399㎛ in source temperature 20℃ and inlet temperature 20℃, and the largest MMD was 5.270㎛ in source temperature 20℃ and inlet temperature 200℃. Increasing trends for GMD, GSD, and MMD were observed with same source temperature and increase of inlet temperature. MMD for inhalation toxicology testing in EPA guidance is less than 4㎛. In our results. inlet temperature 20 and 50℃ in source temperature 20℃, and inlet temperature 20 to 150℃ in source temperature 50 and 70℃ were conformed to the EPA guidance. MMD for inhalation toxicology testing in OECD and EU is less than 3㎛. In our results, inlet temperature 20 and 50℃ in source temperature 20, 50, and 70℃ were conformed to the OECD and EU guidance.

• Structural Engineering and Mechanics
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• 제72권6호
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• pp.737-746
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• 2019

Concrete mechanical properties change constantly with age, temperature, humidity and the other environmental factors. This research studies the effects of temperature and age on the development of concrete elastic modulus by a series of prism specimens. Elastic modulus test was conducted at various temperatures and ages in the laboratory to examine the effects of temperature and age on it. The experimental results reveal that the concrete elastic modulus decreases with the rise of temperature but increases with age. Then, a temperature coefficient K is proposed to describe the effects of temperature and validated by existing studies. Finally, on the basis of K, analytical models are proposed to determine the elastic modulus of concrete at a given temperature and age. The proposed models can offer designers an approach to obtain more accurate properties of concrete structures through the elastic modulus modification based on actual age and temperature, rather than using a value merely based on laboratory testing.

• 대한기계학회논문집
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• 제3권4호
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• pp.173-180
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• 1979

Temperature distriburion in a hollow chlinder has been analyzed mathematically. Unsteady condition considered assumed a constant heat flux input from the inside. The results are compared with experimental results of surface temperature rise of a gun barrel during continuous firing. Their agreements are acceptable. Effects of various dimensionless parameters on the surface temperature rise are discussed. For small Biot numbers, the external survface temperature approaches more rapidly to the steady temperature. Temperature difference between internal and external surfaces becomes greater for small Biot number. Steady solution assumed that the gas temperature inside the cylinder varies periodically. Relative amplitude and phase angles between the gas temperature and the internal or external surface temperature are obtained. Phase angles become smaller for large radiancy of gas temperature variation, small external Biot number, or large internal biot number. Relative amplitudes become samller as radiancy of gas temperature variation and internal Biot number become smaller. or external Biot number becomes larger. The solution obtained in this paper can be applied to gun barrels, heat pipes used in heat excangers, and reciprocation engines.

• 한국환경보건학회지
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• 제36권1호
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• pp.20-26
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• 2010

Temperature change has been shown to affect daily mortality even though different analytical methods produce different results. The effect of air pollution on the relationship between the temperature and the mortality is not large, although differences exist between temperature models. The aim of this study was to examine how the temperature change affected the daily mortality in Seoul by comparing the results from the temperature model using two study periods: one from 1994 to 2007 and the other from 1997 to 2007. Generally mean temperature, minimum temperature and Q10 temperature was derived as an optimal model, even though there are differences between age and cause of death. The analysis of threshold using total mortalities in all ages from 1994 to 2007 and from 1997 to 2007 showed that the number of the deaths increased 7.02% (95% CI: 6.06~7.98) and 2.51% (95% CI: 1.83~3.19), respectively as the mean temperature increased $1^{\circ}C$ from a threshold temperature of $27.5^{\circ}C$ and $25.7^{\circ}C$ respectively. These results indicated that the temperature has less effect on the number of death than does an extreme heat wave period.

• 임산에너지
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• 제21권1호
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• pp.1-6
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• 2002

본 연구는 MDF로 제조된 우드세라믹을 이용하여 온돌마루판 시공 시 하부소재로서의 사용가능성을 검토하고자 실시하였다. 650℃와 800℃로 소성하여 제조된 우드세라믹을 발열판 위에 올려놓고 발열판의 온도 및 시간의 경과에 따른 우드세라믹의 표면온도의 변화를 측정하였다. 우드세라믹의 표면온도는 밀도가 증가함에 따라 표면온도가 증가하였으며, 바닥온도의 변화에 따른 표면온도는 바닥온도가 증가함에 따라 표면온도가 증가하여, 측정온도가 높을수록 열전도가 빠름을 알 수 있었다. 그러나 우드세라믹 제조 시 소성온도에 따른 표면온도의 변화는 뚜렷한 차이를 발견할 수 없었다.

• 한국환경과학회지
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• 제16권8호
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• pp.897-906
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• 2007

Effect of seawater temperature (temperature) on the production of anchovy, Engraulis japonica and laver, Porphyra tenera Kjellman, were investigated in the eastern part of South Sea of Korea (ESS). Bimonthly temperature data (Feb., Apr., Jun., Aug., Oct., Dec.) from 1980 to 2002 were collected from Korean Oceanographic Data Center (KODC) and monthly anchovy catch and laver production from 1980 to 2002 were used from published sources by the Ministry of Maritime Affairs & Fisheries, Korea. Effects of temperature on the two organisms were examined in four cases. In case of lower anchovy catch and higher laver production (1993), temperature during main spawning season of anchovy was about $0.2-0.6^{\circ}C$ lower than normal condition, and temperature during seed collecting season of laver in Namhaedo, Kojedo went down below $22.0^{\circ}C$. In case of higher anchovy catch and higher laver production (1995), optimum temperature for catch was formed in main fishing ground, temperature for seed collection was lower than $22.0^{\circ}C$, In case of lower anchovy catch and lower laver production (1996), temperature for spawning and catch was about $0.6-1.6^{\circ}C$ lower than normal condition, and temperature during seed collection in nursery was about $0.5-1.0^{\circ}C$ higher than optimum temperature for seed collection. In case of higher anchovy catch and lower laver production (1998), temperature during main fishing and spawning season was about $1.0-1.8^{\circ}C$ higher than normal condition, and temperature during laver seed collection in nursery was $1.5^{\circ}C$ higher than optimum temperature for seed collection.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1231-1235
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• 2004

The needs of micro scale thermal detecting technique are increasing in biology and chemical industry. For example, Thermal finger print, Micro PCR(polymer chain reaction), ${\mu}TAS$ and so on. To satisfy these needs, we developed a DTSA(Diode Temperature Sensor Array) for detecting and controlling the temperature on small surface. The DTSA is fabricated by using VLSI technique. It consists of 32 ${\times}$ 32 array of diodes (1,024 diodes) for temperature detection and 8 heaters for temperature control on a 8mm ${\times}$ 8mm surface area. The working principle of temperature detection is that the forward voltage drop across a silicon diode is approximately proportional to the inverse of the absolute temperature of diode. And eight heaters ($1K{\Omega}$) made of poly-silicon are added onto a silicon wafer and controlled individually to maintain a uniform temperature distribution across the DTSA. Flip chip packaging used for easy connection of the DTSA. The circuitry for scanning and controlling DTSA are also developed

• 전기의세계
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• 제15권5호
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• pp.1-5
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• 1966

The stability and safety of operation of a reactor is determined mainly by the sign and magnitude of its reactivity responses to temperature changes. Reactors are subject to temperature fluctuations due to the changes in reactor power and ambient temperature. These temperature fluctuations cause reactivity disturbances through changes in the nuclear and physical properties of the core. Because of these important phenomena by the temperature effects, a large portion of study and testing on a reactor design has been conducted. In this experiment the overall temperature coefficient of the TRIGA MARK-II reactor is measured. The basic procedure is to change the tgemperature of the water moderator, and from the movements of a newly recalibrated control rod(this is necessary due to the effects of fuel burn-up and control rod depression) required to mintain criticality, the reactivity worth of the temperature change is determined. From this measurement, the overall temperature coefficient seems to be smoothly varying, almost a linear function of temperature, and a value of approximately -0.267${\c}$/$^{\circ}C$ can be obtained for an average temperature range from $17.6^{\circ}C$ to $32.5^{\circ}C$.

• Journal of Biosystems Engineering
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• 제23권1호
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• pp.83-90
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• 1998

In this paper the automatic system for dairy cattle has been desisted such as body temperature measuring unit, feed supplying unit and temperature control unit. Since e disease is strongly related to the body temperature of cattle, early detection of the abnormal temperature would prevent the severe problems which nay occur in dairy farms. An electronic component AD590J is used as temperature sensor for the system, The device is highly robust against the noise since the output signal is the current so it can be applied to a long distance sensing The resolution of signal is 0.1$^{\circ}C$ and the current is 10㎷ Also 12-bit A/D converter is desisted fir interfacing the sensor with a one-chip microprocessor. A temperature measuring experiment using the developed system has been done for measuring the temperature of human beings and the system was proven to be useful for measuring the body temperature of dairy cattle properly. A geared AC motor is used for the feed supplying unit The heater and fm are used as temperature control unit. The feed supplying unit and temperature control unit are well operating in the laboratory experiment.

• 기본간호학회지
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• 제20권2호
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• pp.108-117
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• 2013

Purpose: The purpose of this study was to identify the factors that affect body temperature in elderly operation patients using a warming method and to examine differences in post operative body temperature by characteristics of the patients. Methods: Data were collected from 200 patients, aged 65 years or more undergoing surgery with a warming method. The data were analyzed using descriptive statistics, t-test, ANOVA, Scheffe's test and multiple regression with the SPSS 18.0 Program. Results: The mean score for body temperature of elderly operation patients using a warming method after surgery was $36.1{\pm}0.6^{\circ}C$ including 74 patients with hypothermia and 126 patients with normal body temperature. The body temperature according to general characteristics differed by age and whether the surgery was emergency surgery or not. The body temperature according to surgery-related factors differed by anesthesia type, length of operation, anesthesia time, magnitude of surgical procedure, amount of fluid, transfusion requirements, and preoperative body temperature. Factors influencing body temperature were age, BMI, transfusion requirements and preoperative body temperature. Conclusion: The results indicate that age, BMI, transfusion requirements and preoperative body temperature significantly influenced on body temperature after surgery. Thus preoperative body temperature needs to be maintained through pre-warming as a nursing intervention.