• 한국동물학회지
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• 제35권3호
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• pp.263-270
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• 1992

Responses of immunoreactive atrial natriuretic peptide (ir-ANP) to environmental temperature were studied in the freshwater catfish, Silums usotus, acclimated at various temperatures for one week. According to increase in environmental temperature, plasma sodium and chloride concentrations, and osmolality were significantly increased, while hematocrit showed a marked decrease. When the catfishes frere acclimated at cold $(3^{\circ}C)$ or warm $(18^{\circ}C)$ temperatures, ir-ANP contents in the atrium and bulbus arteriosus were significantly lower than those at $9^{\circ}C.$ However, ventricular contents of ir-ANP urere not different among the three groups.Levels of plasma ir-ANP in the catfish increased in response to the increment of acclimated temperature. On the basis of these results, we suggest that the environmental temperature may modulate synthesis and secretion of ir-hUP in the fish. We also suggest that changes of plasma ir-ANP levels may be associated with the control of body fluid homeostasis.

• 한국자기학회지
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• 제5권5호
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• pp.416-420
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• 1995

An attempt has been made to investigate the mechanism of magnetic alignment in the magnets produced by upset forging the $Pr_{20}Fe_{74}B_{4}Cu_{2}$ cast bulk alloy. Upset forging of the cast alloy was carried out for 20 sec to an 80 % thickness reduction (strain rate : $4{$\times}10^{-2}s^{-1}$) in an open die configuration at varying temperatures in the range $600^{\circ}-900^{\circ}C$. It has been found that the upset forging process at temperatures above $800^{\circ}C$ can achieve a magnetic alignment to a great extent from copper-containing Pr-Fe- B-type cast ingot. The growth manner of the ferromagnetic $Pr_{2}Fe_{14}B$ matrix grain in Pr-Fe-B-type alloys was studied by examining the morphology change of the matrix grain in sintered body, and it was found that the matrix grains grew in anisotropic manner such that the grain grew more rapidly along the a- or b-axis than along the c-axis. This anisotropic grain growth led to the plate-like shape of the matrix grain. The magnetic alignment during the upset forging was attributed to grain boundary gliding of the plate-like grains, and the geometry of the grains in the cast ingot and the presence of a large amount of the praseodymium-rich grain boundary phase were thought to play a key role in the achievement of magnetic alignment.

• Fisheries and Aquatic Sciences
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• 제22권1호
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• pp.3.1-3.8
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• 2019

The purpose of this study is to investigate the changes in growth, hematological parameters, and plasma components of juvenile starry flounder, Platichthys stellatus, following exposure to varying arsenic concentrations present at different water temperatures. P. stellatus (total length, $15.9{\pm}0.4cm$; body weight, $62.2{\pm}4.2g$) were exposed for 4 weeks to waterborne arsenic (sodium arsenite, As) at 0, 150, 300, and $600{\mu}g/L$ at temperatures of $12^{\circ}C$ and $18^{\circ}C$. Toxic effects of As exposure on P. stellatus were higher at the higher temperature and the growth and hematological parameters measured decreased with increasing arsenic concentration, while the concentration of plasma components measured increased. This indicates that waterborne As exposure and water temperature can cause toxic effects on growth, hematological parameters, and plasma components in Platichthys stellatus.

• 한국수산과학회지
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• 제53권6호
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• pp.918-924
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• 2020

This study investigated diurnal fasting and postprandial total ammonia nitrogen (TAN) excretion rates in juvenile Oplegnathus fasciatus (rock bream; mean body weight 45.8±1.1 g) at three temperatures (15, 20, and 25℃) in a recirculating system (three replicates). The fish were hand-fed twice daily (09:00 and 17:00 h) with commercial food (46.7% protein) until satiation. The results showed that the fasting and postprandial TAN excretion rates were temperature-dependent. The mean hourly rates were 7.7 (15℃), 10.2 (20℃), and 11.9 (25℃) mg kg fish-1 h-1 for fasting and 34.0 (15℃), 47.8 (20℃), and 60.2 (25℃) mg kg fish-1 h-1 for postprandial. At each temperature, two postprandial TAN excretion peaks were observed 2-4 h after feeding; the second peak was always higher. The TAN loss to nitrogen consumption ratio was 41.1-46.8 % and increased significantly with increasing temperature. Temperature affected fasting and postprandial TAN excretion in juvenile rock bream, providing insight for culture management.

• 감성과학
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• 제14권3호
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• pp.435-444
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• 2011

유비쿼터스 헬스케어 기술 및 휴대용 전자기기의 발전은 지속적으로 전원을 공급하기 위한 새로운 에너지원을 요구하고 있으며, 이러한 점에서 의류를 통한 인체 에너지 수확 시스템의 연구가 요청되고 있다. 인체에너지를 수확하는 방식의 하나인 열전은 인체와 주위 환경간의 온도차이로부터 에너지를 수확하는 방식으로, 본 연구에서 의복을 통한 열전에너지 수확의 기초자료를 확보하기 위하여 인체표면 온도의 분포를 실증적으로 고찰하였다. 이를 위해 체표 구간을 설정하고 구간별 온도분포를 분석하였다. 분석 결과, 상체의 체표온도가 하체에 비해 높았고 특히 심장과 가깝고 혈류량이 많은 몸통 부위의 체표온도가 높았다. 뒷목과 등, 허리의 후면 부위 체표온도가 앞면에 비해 높았으며, 팔 부위의 경우 위쪽 부위의 체표온도가 아래쪽 부위보다 높고 팔 후면이 정면과 측면에 비해 온도가 낮게 나타났다. 체표 구간별 평균 온도와 환경온 간의 차이값이 가장 높아 열전 수확 기능구조 설치에 가장 적합한 위치는 뒷목 부위로 나타났고, 등과 허리 부위, 측면 어깨부위, 가슴 부위, 정면 위팔 부위, 배 부위가 그 뒤를 이었다. 이러한 인체표면 온도분포 결과를 토대로, 본 연구에서는 열에너지 수확의류 개발을 위한 기본 지침을 도출하였다.

• 대한의용생체공학회:의공학회지
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• 제35권5호
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• pp.160-168
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• 2014

Continuous body temperature monitoring is useful and essential in diverse medical procedures such as infection onset detection, therapeutic hypothermia, circadian rhythm monitoring, sleep disorder assessment, and gynecological research. However, the existing thermometers are too invasive or intrusive to be applied to long-term body temperature monitoring. In our previous study, we invented the bi-medium deep body thermometer which can noninvasively and continuously monitor deep tissue temperature. And the ratio of thermal resistances expressed as K-value should be obtained to estimate body temperature with the thermometer and it can be different under various measurement environments. Although the device was proven to be useful through preliminary simulation test and small group of human study, the experimental environment was restrictive in our previous approach. In this study, a finite element simulation was executed to obtain the K-value and evaluate the accuracy of bi-medium thermometer under various measurement environments. In addition, K-value estimation equation was developed by analyzing the influence of 5 measurement environmental factors (medium length, medium height, tissue depth, blood perfusion rate, and ambient temperature) on K-value. The results revealed that the estimation accuracy of bi-medium deep body thermometer based on computer simulation was very high (RMSE < $0.003^{\circ}C$) in various measurement environments. Also, bi-medium deep body thermometer based on K-value estimation equation showed relatively accurate results (RMSE < $0.3^{\circ}C$) except for one case. Although the K-value estimation technology should be improved for more accurate body temperature estimation, the results of finite element simulation showed that bi-medium deep body thermometer could accurately measure various tissue temperatures under diverse environments.

• 한국의류산업학회지
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• 제20권2호
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• pp.202-209
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• 2018

This study examined thermo-physiological responses according to the design change of construction site working clothes (control (C) working clothes; prototype (P) working clothes). We measured rectal temperature, skin temperature, micro-climate within the clothes and sweat rate. In the evaluation of physiological functionality, based on pattern improvement in working clothes, P working clothes showed significantly lower rectal temperatures, trunk and thigh skin temperatures than C working clothes. It is preferable that rectal temperature should be kept low during work that is not favorable to an increase in body temperature. P working clothes were more physiologically functional than C working clothes. In addition, P working clothes showed significantly lower temperatures in the trunk and thigh parts in a micro climate temperature. We could explain that the side seam zipper on the pants and the gusset on armpit parts create an air permeability effect of lowering the temperature of micro-climate. Aggressive ventilation through the slit of the garment is an important factor for the restoration of the physiological function of the worker at rest between work. Sweat rate showed a higher level in C working clothes than P working clothes. When working in a hot environment, workwear needs to be designed so that the worker is not exposed to thermal stress. Therefore, it was evaluated that the P work clothes used in this study alleviated the physiological burdens of heat.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1159-1163
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• 2006

This experiment was performed to examine the influences of high ambient temperature on milk production, nutrient digestibility, energy and protein sufficiency ratio, and plasma metabolites concentration in lactating cows. In a $2{\times}2$ crossover design, four multiparous lactating Holstein cows were maintained in a chamber under treatment of constant moderate ($18^{\circ}C$) ambient temperature (MT) or high ($28^{\circ}C$) ambient temperatures (HT). The DMI and milk protein yield were significantly lower in HT (p<0.05). The milk yield, milk lactose yield, and milk SNF yield tended to be lower in HT (p<0.10). No statistical differences for 4% fat-corrected milk and milk fat yield were observed. Rectal temperatures were significantly higher in HT than MT (p<0.05). The apparent DM, OM, ether extract, CF, and ash digestibility did not differ between treatments. On the other hand, the apparent CP digestibility was increased significantly (p<0.05) and nitrogen free extract tended to increase (p<0.10) in HT. The sufficiency ratio of ME and DCP intake for each requirement tended to be lower in HT than in MT (p<0.10). Concentrations of total protein (TP), albumin, and urea nitrogen in plasma did not differ between treatments. Plasma 3-methylhistidine (3MH) concentration as a marker of myofibrillar protein degradation tended to be higher in HT (p<0.15). In conclusion, high ambient temperature was associated with a lower energy and protein sufficiency ratio, and decreased milk protein production, even though the body protein mobilization tended to be higher.

• 한국전기전자재료학회논문지
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• 제16권12S호
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• pp.1205-1209
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• 2003

We investigated the effects of calcination temperatures on the sintering behaviors and microwave dielectric Properties of (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ system. Highly densified samples were obtained at the sintering temperatures below 100$0^{\circ}C$ with additions of 0.45 wt.%B $i_2$ $O_3$ and 0.55 wt.% $V_2$ $O_{5}$. From the examination of the existing phases and microstructures before and after sintering of (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ system which is calcined at the various temperatures ranging from 80$0^{\circ}C$ to 100$0^{\circ}C$, it was found that higher Q${\times}$ $f_{o}$ values were obtained when unreacted phases in calcined body were reduced. When calcined at 100$0^{\circ}C$ and sintered at 90$0^{\circ}C$, it consists of hexagonal as. a main phase with uniform microstructure and exhibits Q${\times}$ $f_{o}$ value of 42,000 GHz and dielectric constant of 22. 22. 22.

• Ocean and Polar Research
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• 제32권3호
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• pp.229-236
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• 2010

A study was conducted to investigate the effect of water temperature and photoperiod on the oxygen consumption of the fasting juvenile Pacific cod Gadus macrocephalus (mean body weight 79.9${\pm}$2.0 g) in order to quantify metabolic response of the species under given conditions. The oxygen consumption rate (OCR) of G. macrocephalus was measured under a combination of four different water temperatures (7, 10, 13 and $16^{\circ}C$) and three different photoperiods (24L:0D, 12L:12D and 0L:24D) with an interval of 5 minutes over a 24-hour period using a closed recirculating respirometer. Three replicates were set up in each treatment. OCRs increased with increased water temperatures under all photoperiod conditions (P<0.001). Mean OCRs at 7, 10, 13 and 16oC ranged from 793.7~1108.4, 1145.7~1570.3, 1352.8~1742.5 and 1458.2~1818.6 mg $O_2$ $kg^{-1}$ $h^{-1}$, respectively. Under all water temperature conditions except $7^{\circ}C$ (P<0.001), mean OCRs of G. macrocephalus were the highest in continuous light (24L:0D) followed by 12L:12D and 0L:24D photoperiods. Mean OCRs of fish exposed to the 12L:12D photoperiod were significantly higher during the light phase than during the dark phase under all temperature conditions (P<0.001). $Q_{10}$ values ranged from 3.19~5.13 between 7 and $10^{\circ}C$, 1.41~1.74 between 10 and $13^{\circ}C$ and 1.15~1.35 between 13 and $16^{\circ}C$, respectively. Based on overall results, water temperature, photoperiod and their combinations exerted a significant influence on the metabolic rate of juvenile cod. This study provides empirical data for estimating the amount of oxygen demand and managing the culture of cod under the given water temperatures and photoperiods.