• Journal of the Korean Society of Radiology
• /
• v.16 no.6
• /
• pp.751-759
• /
• 2022

Currently, ultrasound examination for diagnostic ultrasound and health examination purposes is widely used, and it is showing an increasing trend due to the application of health insurance. However, the risk of ultrasound has not been clearly identified so far, and in this study, surface and deep temperature changes according to frequency and mode were measured by using a tissue mimicking phantom and TI and MI values were compared. A simulated phantom was manufactured by adding a small amount of kappa-caraginan powder with acoustic characteristics similar to that of the human body and potassium chloride for solidification, and the change of surface and depth temperature was measured using a surface thermometer and a probe thermometer. As a result, the convex probe using low frequency showed a higher temperature increase than the linear probe using high frequency, so there was a significant difference, and the temperature increase was the highest on the surface, and the depth of 1cm showed a temporary temperature increase, but there was no significant temperature change. There was no change in the deep temperature of 5 cm to 15 cm, and the TI and MI values did not change during the test time. Since only the surface temperature rose during the 15-minute test and there was no temperature change in the core, so it is not expected to show a temperature change that is harmful to the human body. However, it is thought that prolonged examination of one area may cause temperature rise, so it should be avoided.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.17 no.2
• /
• pp.125-130
• /
• 2005

This study was peformed to investigate the phase change temperature, the supercooling, the maintenance time of liquid phase and the change rate of volume of TMA 30 $wt\% clathrate compound with additives. TMA 30 $wt\% clathrate compound with additive was cooled at heat source temperature of $-6^{circ}C$. The additives are ethylene glycol and chloroform. Their concentration are 0.1$wt\% respectively. The experimental results showed that the phase change temperature was not affected by additives and this was average $5.3^{circ}C$. Also the supercooling and the maintenance time of liquid phase were decreased by additives. Especially, the average value of supercooling showed by $8.8^{circ}C$ and the maintenance time of liquid phase was by 19 minutes in the case of chloroform 0.1$wt\%. Additionally, the average change rate of volume showed by $1.26{\~}1.31\%$ according to additives and the volume was decreased by the phase change from liquid to solid.

• The Journal of Fisheries Business Administration
• /
• v.47 no.4
• /
• pp.31-44
• /
• 2016

The purpose of this study is to analyze the climate change exposure of fisheries and fish species in the southern sea of Korea under the RCP climate change scenarios. The extent of exposure was calculated through weighted sum of the sea temperature forecasted by National Institute of Fisheries Science, and the weight were obtained from the time-space distribution of each fisheries or species, based on the micro-data for the fishing information reported by each fisherman. Results show that all the exposed sea temperature of RCP8.5 is higher than that of RCP4.5 in year 2100 as well as in near 2030, therefore it is thought to be very important to reduce the GHG emission even in the short term. The extent of exposure was analyzed to be comparatively high especially in the fisheries such as anchovy drag nets and species like cod, anchovy and squid. Meanwhile the method of this study is considered to be excellent to obtain the accurate extent of exposure under RCP scenarios, and therefore it is applicable on assessing the vulnerability of climate change in fisheries.

• Journal of Sensor Science and Technology
• /
• v.17 no.4
• /
• pp.261-266
• /
• 2008

In this paper, we present thermal characteristics of high-temperature measurement sensor using fiber Bragg grating(FBG), including peak reflectivity, FWHM bandwidth and various normalized refractive index change along temperature variation. The temperature stability of FBG temperature sensor can be changed by varying the refractive index change and grating length. The proposed FBG temperature sensor can measure up to about $600^{\circ}C$ and 1000 hours of heating time.

• Journal of Animal Environmental Science
• /
• v.20 no.2
• /
• pp.49-56
• /
• 2014

The climate of the earth is expected to change rapidly and continuously. Despite climate change is expected to impact on productivity of crop and livestock, a study for adaptation and impact of livestock to global warming is not enough. This study was performed to develop a method to evaluate the effects of heat stress on dairy cattle. Feedlot environment and health status of livestock were measured through an infrared thermography camera and a temperature-humidity sensor. Environmental factors such as temperature and humidity were measured to calculate the Temperature humidity index (THI). The change of the milk yield was similar to THI data pattern, suggesting that THI might play an important role to predict the effect of climate change on dairy cattle. THI data would be useful to predict long-term climate change effects on dairy cattle with RCP8.5 scenario.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.14 no.2
• /
• pp.422-429
• /
• 1990

The experimental study investigates two aspects of counterflow sensible heat regenerator operation. First, it examines the regenerator performance in periodic steady state operation with spatially nonuniform inlet temperature in one of the fluid stream. Second, the study examines the transient response of a regenerator to a step change in the inlet temperature of one of the fluid streams. The effect of transient inlet temperatures is analyzed in terms of the response of the outlet fluid temperatures to a step change in temperature of one of the inlet fluid streams. The effect of temperature nonuniformities is analyzed in terms of the change of temperature nonuniformities is analyzed in terms of the change in steady state effectiveness due to a circumferential temperature distribution in one of the inlet fluid streams. an experimental analysis has been conducted using a counterflow, parallel passage, and rotary regenerator made from polyethylene film. Efficiencies follow similar trends with increasing matrix to fluid capacity rate ratio for the balanced and symmetric regenerator with nonuniform inlet temperature.

• Korean Journal of Ecology and Environment
• /
• v.55 no.4
• /
• pp.341-351
• /
• 2022

The physiological characteristics, growth, and yield of each regional rice variety ('Odaebyeo', 'Saechucheong', 'Ilmibyeo') were investigated depending on the impact of changes in temperature and CO₂ concentration. Experiments were conducted with a control group, which reflected atmospheric CO₂ concentration and temperature, and treatment groups, in which the CO₂ concentration and temperature were increased by 250 ppm and 2.0℃ from those in the control group. The results showed that the increase in CO₂ concentration and temperature reduced the growth and yield of the rice 'Odaebyeo', but did not substantially change the productivity of the 'Saechucheong' and 'Ilmibyeo'. The increase in CO₂ concentration and temperature increased stomatal conductance and rate of transpiration of the 'Odaebyeo' variety, thereby decreasing its water use efficiency (WUE). In contrast, the increase in CO₂ concentration and temperature increased the photosynthetic rate and WUE of the 'Saechucheong' and 'Ilmibyeo' varieties. The gradual change in climate is considered to directly affect growth and development of rice and diversely affect the productivity of each variety. Therefore, it is necessary to implement technological development, select regionally optimal rice varieties, develop new rice varieties, as well as conduct long-term monitoring of each rice variety for climate adaptation to counter global warming.

• Journal of the Korean Home Economics Association
• /
• v.29 no.1
• /
• pp.13-25
• /
• 1991

We measured change of peripheral skin temperature and mean skin temperature when the upper arm and thigh are pressured in order to know the effect of skin pressure applied by clothing on blood circulation. After release from pressure, we observed also recovery condition. At the same time, we examined relation between pressure and a feeling of thightness. Three physiques of healthy females, namely slender, standard and plump, served as subjects. We used continuous restraint method with skin pressure applied by experimental fabric for 10 min. As a result of this experiment, we obtained following findings. 1. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under upper arm restraint. The peripheral and mean skin temperature decreased with the lapse of restraint time. A remarkable tendency observed according to the increase of restraint pressure. Recovery condition after release from pressure not yet recovered to original state, for all after a lapse of 10 min. 2. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under thigh restraint, especially different physique was remarkable among them. The peripheral skin temperature decreased or decreased. Recovery condition after release from pressure was the same upper arm. 3. Main factor affecting the evaluation of a feeling of tightness was restraint pressure. The value of pressure sensation made remarkable declined after a lapse of 10 min restraint time. Individual differences, however, were shown in pressure sensation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11b
• /
• pp.413-422
• /
• 2000

Samples of banana were dried in a two-stage heat pump dryer capable of producing stepwise control of the inlet drying air temperature while keeping absolute humidity constant. Two stepwise air temperature profiles were tested. The incremental temperature step change in temperature of the drying air about the mean air temperature of 30 $^{\circ}C$ was 5 $^{\circ}C$. The total drying time for each temperature-time profile was about 300 minutes. The drying kinetics and color change of the products dried under these stepwise variation of the inlet air temperature were measured and compared with constant air temperature drying. The stepwise air temperature variation was found to yield better quality product in terms of color of the dried product. Further, it was found that by employing a step-down temperature profile, it was possible to reduce the drying time to reach the desired moisture content.

• Journal of Environmental Health Sciences
• /
• v.37 no.6
• /
• pp.397-405
• /
• 2011

Objectives: The impact of climate change on the health has been of increasing concern due to a recent temperature increase and weather abnormality, and the research results of the impact varied depending on regions. We synthesized risk estimates of the overall health effects of low and high temperature taking account of the heterogeneity. Methods: A comprehensive literature search was conducted using PUBMED to identify journal articles of low and/or high temperature effects on mortality. The search was limited to the English language and epidemiological studies using time-series analysis and/or case-crossover design. Random-effect models in meta analysis were used to estimate the percent increase in mortality with $1^{\circ}C$ temperature decrease or increase with 95% confidence intervals (CI) in cold or hot days. Results: Twenty three studies were presented in two tables: 1) low temperature effects; 2) high temperature effects on mortality. The combined effects of low and high temperatures on total mortality were 2% (95% CI, 1-4%) per $1^{\circ}C$ decrease and 4% (95% CI, 2-5%) per $1^{\circ}C$ increase of temperature, respectively. Conclusions: This meta analysis found that both low and high temperatures affected mortality, and the magnitude of high temperature appeared to be stronger than that of low temperature.