• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.2 s.257
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• pp.182-189
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• 2007

This paper is concerned with the empirical flow stress constitutive equation of steel sheets for an auto-body with the variation of temperature and strain rate. In order to represent the strain rate and temperature dependent behavior of the flow stress at the intermediate strain rates accurately, an empirical hardening equation is suggested by modifying the well-known Khan-Huang-Liang model. The temperature and strain rate dependent sensitivity of the flow stress at the intermediate strain rate is considered in the hardening equation by coupling the strain, the strain rate and the temperature. The hardening equation suggested gives good correlation with experimental results at various intermediate strain rates and temperatures. In order to verify the effectiveness and accuracy of the suggested model quantitatively, the standard deviation of the fitted result from the experimental one is compared with those of the other two well-known empirical constitutive models such as the Johnson-Cook and the Khan-Huang-Liang models. The comparison demonstrates that the suggested model gives relatively well description of experimental results at various strain rates and temperatures.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.181-187
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• 1999

In this study, the effect of residual stress on mechanical strength was investigated with 1 kind of whiteware body and 4 kinds of glazes which are produced in succeeding ceramic art place. Using dipping method, the body was coated for different times in order to manipulate the coating thickness and sintered in the different temperatures ($1200^{\circ}C$, $1250^{\circ}C$, $1300^{\circ}C$, $1350^{\circ}C$) for two thus hours. The sintered bodies were characterized by XRD, EPMA, FEM and UTM in order to study the forming of reaction layer between body and glazes, residual stresses and the effects of residual stresses on mechanical strength of pottery. At $1300{\circ}C$, we obtained maximum density and mechanical strength. By the finite element method, the residual stresses in surface of body were minimum in specific thickness of glazes and the mechanical strength of body in that thickness of glazes showed maximum when the firing temperature was settled.

• Fashion & Textile Research Journal
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• v.22 no.1
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• pp.66-75
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• 2020

This study helps develop cool-touch functional dance sportswear. We suggest a draft design for dance sportswear that chooses appropriate cool-touch functional materials based on an investigation of the changes of body surface temperature before and after exercise, the physical properties of cool-touch materials on the market, and the preference for cooling tools. The results are as follows. First, cool-touch functional sportswear products on the market utilize materials such as PCM, Delta fabric, high gauge fabric, and ice chips as well as incorporate functions such as UV block and eyelets for enhanced breathability. Polyester and polyurethane fibers are mainly used for cool-touch functional sportswear. Second, the neck area showed the highest surface temperatures (32.7℃ and 32.1℃) before and after exercise. Body surface temperatures measured after exercise were also lower than temperatures measured before exercise when wearing dance sportswear. Third, as for the physical properties of cool-touch materials, material 1 showed amaximum drying speed (130 min), material 3 the best moisture absorption speed (122 × 132 min), and material 4 the best thermal conductivity (0.013 7 w/m·K). Fourth, a draft design for a cool-touch functional dance sportswear was suggested, including a neckband made of removable soft PVC material on the neck area and applying material 4 in F1, B4, S2 and lower arm areas and material 1 in the armpit area. Deodorant tape was also attached to the armpit area for added comfort and antibacterial deodorant effect.

• Journal of Powder Materials
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• v.10 no.1
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• pp.34-39
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• 2003

Porous TiNi bodies were produced by Self-propagating High-temperature Synthesis (SHS) method from a powder mixture of Ti and Ni. Porosity, pore size and structure, mechanical property, and transformation temperature of TiNi product were investigated. The average porosity and pore size of produced porous TiNi body are 63% and $216\mutextrm{m}$, respectively. XRD analysis showed that the major phase of produced TiNi body is B2 phase. Its average fracture strength and elastic modulus measured under dry condition were $22\pm2$ MPa and $0.18\pm0.01$GPa, respectively. It could be strained up to 7.3 %. The transformation temperatures determined by DSC showed the $M_s$ temperature of $67^{\circ}C$ and $A_f$ temperature of $99^{\circ}C$.

• Journal of Aquaculture
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• v.6 no.4
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• pp.273-284
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• 1993

Ion concentrations and osmolarities of the body fluid and oxygen consumption of the larvae of the freshwater crab, Eriocheir japonicus under the influence of various salinities and water temperatures were studied. The levels of $Na^+\;and\;Cl^-$ ions in the body fluid of the crab placed in the low salinities (freshwater and $30\%$ seawater) were higher at the low temperature $(16^{\circ}C)$ than high temperature $(30^{\circ}C)$. However, the crab in the high salinity $(90\%\; seawater)$, those ions in the body fluid were higher at the high temperature $(30^{\circ}C)$ than the low temperature $(10^{\circ}C)$ When the zoea larvae were young (first and second stages), the ion concentrations of the body fluid were more affected by salinities and temperatures of the media. The salinity levels of the media more influenced the levels of $K^+$ ions of the body fluid of the larvae than the temperature. The osmolarities of the body fluid of the larvae were almost isotonic when they were placed at $70\%$ seawater $(24.5\%o)$. Oxygen consumption of individual larva was lower in zoea 1 and 2 stages than the other stage larvae. The high oxygen consumption of the larvae was observed at $70\%$ seawater compared to the other salinity levels.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.91-94
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• 2012

This study was conducted to develop an algorithm for determination of abnormal body temperature in piglets through skin and core temperature database at normal condition. 5 piglets (mean BW : 46 kg) were employed for the experiment. They were adapted in the individual metabolism cage set at $22.5{\pm}2.0^{\circ}C$ of room temperature for 2 weeks before the measurement of body temperature. Ear, neck, head and subcutaneous neck temperature (as core temperature) of piglets were measured for every 1 minute during 30 consecutive days through 1mm k-type thermocouple wire and NI-devices (National Instruments Corporation, Austin, Texas, USA). Body temperature data were accumulated and integrated into the 1 day unit. Change of daily mean skin and core body temperatures in piglets were lowest at around 06:00, highest at around 14:00 and gradually decreased until the day after 06:00. Each skin temperatures were varied with the measuring site and largely depended on the room temperature changes. Established database of skin and core body temperature in piglets through this study can be applied to develop an algorithm for monitoring and determining the abnormal condition of animal by using radio frequency identification.

• Journal of Sensor Science and Technology
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• v.15 no.5
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• pp.362-370
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• 2006

The wireless sensor network (WSN) based ECG and body temperature measuring system for ubiquitous health-care were designed and developed. The system was composed of a wireless sensor network node, base station and server computer for the continuous monitoring of ECG signals and body temperatures of patients at home or hospital. ECG signal and body temperature data, important vital signals which are commonly used in clinical and trauma care, were displayed on a graphical user interface (GUI). The data transfer from sensor nodes on patients' body to server computer was accomplished through a base-station connected to a server computer using Zigbee compatible IEEE802.15.4 standard wireless communication. Real-time as well as historical, ECG data of elderly persons or patients, can also be retrieved and played back to assist the diagnosis. The ubiquitous health care system presented in this study can effectively reduce social medical expenses, which will be increased greatly in the coming aging society.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.7
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• pp.912-918
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• 2011

Newly born lambs have to face challenges in a new environment totally different from that of the uterus. Adaptation to extra-uterine life involves functional changes with almost each organ and system in the body undergoing a series of metabolic and anatomical modifications. Failure to adapt the extra-uterine environment can not only lead to homeostatic disturbances but also lead to the death of the affected lambs. Hematological parameters of newly born lambs show variability that differs between breeds of lambs. The purpose of present study was to determine homeostatic responses and physiological reference values in Kajli breed lambs occurring in the neonatal period through changes in blood profile, respiratory rate, heart rate, live weight and rectal, scrotal and skin temperatures. For this purpose, sixteen clinically fit lambs (males = 10 and females = 6) with a mean body weight $6.92{\pm}0.46$ kg were selected. Physiological data of selected parameters of each Kajli lamb was recorded at three day intervals and hematological parameters at five days for a period of 30 days. In general, statistical analysis showed a significant effect of time (p<0.001) on all the studied physiological and hematological parameters except platelets counts, white blood cells and hemoglobin concentration. The results documented in the current study are an addition to existing knowledge of the physiology of Kajli sheep breed should be helpful in developing feeding, disease diagnoses and treatment protocols for newborn Kajli stock.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.9_10
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• pp.1465-1474
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• 2007

We analyzed the effects of regular Jjimjilbang(Korean sauna) exposure on the heat tolerance in young and old females. Subjects were young(n=7) and old(n=7) females who never had a bath in Jjimjilbang for last year. Jjimjilbang training group took a bath in Jjimjilbang once a week 19 times. Jjimjibang expsure was limited three times per day, Jjimjil were taken free way. To prove the effects of the heat tolerance, Subjects were exposed to hot and humid air$(40.0{\pm}0.5^{\circ}C,\;60{\pm}5%RH)$. In the condition, subjects were taken a foot bathing$(40.0{\pm}0.5^{\circ}C)$ and simulated for 30 min., and rectal temperature, skin temperatures, clothing microclimate, blood pressure, total body weight loss, local sweat and subjective sensation were measured. The results are as follow: Rectal temperature, skin temperatures, clothing microclimate, total body weight and subjective thermal comfort sensation were decreased gradually(p<.001). Local sweat of upper arm was decreased(p<.01). In conclusion. the regular Jjimjilbang exposure has positive effects upon improvement in regulation of body temperature, especially in heat tolerance.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.309-314
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• 2005

This study was to determine whether the massage would enhance the physical relaxation in healthy women, and whether the effects of massage on the relaxation would be different by the applied regions of the body. Five healthy young women participated in the two test sessions of back and lower extremities massage in a chamber controlled at an air temperature of $28^{\circ}C$ and a relative humidity of $50{\pm}5%$. The slow stroke massage with lavender aroma oil for 30 minutes was applied to the subjects with a 10-min. and a 20-min rest time before and after the application, respectively. Rectal temperature decreased and the chest and thigh skin temperatures increased with the massage application, and the changes of the temperatures were greater with lower extremities massage than with back massage. Heart rate also decreased during massage period and tended to be lower with lower extremities massage. Systolic and diastolic blood pressure decreased with lower extremities massage. These results show that the slow stroke massage for 30 minutes can induce physiological responses related with the enhanced relaxation in healthy women, and lower extremities massage is more effective on the physical relaxation rather than back massage.