• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.11
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• pp.884-890
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• 2008

Many researches have been carried out to reduce the emission levels and lower the fuel consumption in SI engines. Recently electronically controlled injection system is widely adapted to a passenger car to achieve these goals. Throttle body is also an important factor which influences on the emissions and engine power. In this study we redesigned a throttle body and conducted an experimental study to see the effects on engine performance and emission characteristics. We could find that idle speed control(ISC) showed stable operation characteristics as the cooling water temperature varied. And CO and HC emissions also satisfied the regulation limit.

• Fashion & Textile Research Journal
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• v.13 no.4
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• pp.635-643
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• 2011

This study was investigated to evaluate the physiological responses on T-shirts manufactured with selected functional materials by body parts which were selectioned on the distribution of sweating and temperature change. Seven healthy men in twenties were participated in a climate chamber of $27{\pm}0.5^{\circ}C$ and $50{\pm}1%RHC$. Three kinds of T-shirts named 'D1', 'D2' and 'Poly' were used as experimental clothings. Four kinds of functional materials of quick absorbing/drying were used in all section in 'D1', but two kinds of functional materials used partially in 'D2'. 'Poly' T-shirts used only polyester. In an experimental schedule of 90 minutes, which were consisted of 'Rest', twice of 'Exercise' and twice of 'Recovery' periods, the subjects walked on a treadmill with 60% of $VO_2max$. As a physiological responses, the microclimate temperature, surface temperature(skin, clothing) and sweat rate were measured. Temperature regulation was kept well in 'D1' rather than other T-shirts. The quick absorbing/drying T-shirts showed its performance well as the exercise goes on the second half. With these results in mind, 'D1' will be more effective for long hours exercise such as climbing rather than short hours exercise.

• Journal of Korean Academy of Nursing
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• v.47 no.4
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• pp.456-466
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• 2017

Purpose: This study was designed to determine the effects of pre-warming on core body temperature (CBT) and hemodynamics from the induction of spinal anesthesia until 30 min postoperatively in surgical patients who undergo total hip replacement under spinal anesthesia. Our goal was to assess postoperative shivering and inflammatory response. Methods: Sixty-two surgical patients were recruited by informed notice. Data for this study were collected at a 1,300-bed university hospital in Incheon, South Korea from January 15 through November 15, 2013. Data on CBT, systemic blood pressure (SBP), and heart rate were measured from arrival in the pre-anesthesia room to 3 hours after the induction of spinal anesthesia. Shivering was measured for 30 minutes post-operatively. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were measured pre-operatively, and 1 and 2 days postoperatively. The 62 patients were randomly allocated to an experimental group (EG), which underwent pre-warming for 30 minutes, or a control group (CG), which did not undergo pre-warming. Results: Analysis of CBT from induction of spinal anesthesia to 3 hours after induction revealed significant interaction between group and time (F=3.85, p=.008). In addition, the incidence of shivering in the EG was lower than that in the CG ($x^2=6.15$, p=.013). However, analyses of SBP, heart rate, CRP, and ESR did not reveal significant interaction between time and group. Conclusion: Pre-warming for 30 minutes is effective in increasing CBT 2 and 3 hours after induction of spinal anesthesia. In addition, pre-warming is effective in decreasing post-operative shivering.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.77-85
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• 2018

Objective : This study was intended to examine the effects of water extract of Prunellae Spica (PS), which is a herb with 'cold' nature based on hot and cold theory of traditional Korean medicine. Methods : Hyperthyroidism was induced in SD rats by LT4 (0.5 mg/kg, i.p.) daily for four weeks. After 2 weeks of LT4 injection, rats were divided randomly into four groups; normal, LT4-induced hyperthyroid control, PS extract (500 mg/kg, p.o.)-treated group, and propylthiouracil (PTU, 10 mg/kg, s.c.)-treated positive group. After 2 weeks of drug treatment, all rats were sacrificed and harvested blood samples and thyroid tissues. The changes of body weight, food and water intake, and body temperature were measured weekly. Serological markers were analyzed in sera using an enzyme-based assay, and thyroid tissues were stained with Hematoxylin & Eosin (H&E). Brain and dorsal root ganglion (DRG) tissues were isolated and analyzed the expression of transient receptor potential (TRP) channels by Western blot. Results : PS extract administration attenuated the loss of body weight and the increase of body temperature in LT4-induced hyperthyroidism rats. PS extract increased the level of thyroid stimulating hormone (TSH) and decreased tiiodothyronine (T3) and tetraiodothyronine (T4). In action mechanism, PS extract regulated the expression of transient receptor potential channel subfamily V member 1 (TRPV1) and transient Receptor Potential channel subfamily M member 8 (TRPM8), the thermoregulators. Conclusion : To conclude, PS extract can improve the symptoms of hyperthyroidism through regulation of the thyroid hormones imbalance and thermoregulation via TRP channels.

• Korean Journal of Materials Research
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• v.16 no.11
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• pp.698-704
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• 2006

In this study, the effect of chill layers occurred in shot sleeve on the molten metal filling was analyzed through computer simulation. The behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. Particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the biggest reduction in chill layers, excellent trimmed surface and the highest density were achieved, suggesting that as the optimal sleeve condition in aluminum high pressure diecasting, especially for highly complex parts like valve body.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.81-90
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• 1992

Five buffaloes kept in normal ambient temperature ($30^{\circ}C$) showed no significant changes in the heart rate, respiratory rate, packed cell volume, plasma constituents and renal hemodymics during intravenous infusion of urea for 4 h. The rate of urine flow, fractional urea excretion, urinary potassium excretion and osmolar clearance significantly decreased while the renal urea reabsorption markedly increased during urea infusion. The decrease of fractional potassium excretion was concomitant with the reduction of the rate of urine flow and urine pH. In animals exposed to heat ($40^{\circ}C$) the rectal temperature heart rate and respiratory rate significantly increased while no significant changes in GFR and ERPF were observed. An intravenous infusion of urea in heat exposed animals caused the reduction of the rate of urine flow with no changes in renal urea reabsorption, urine pH and fractional electrolyte excretions. During heat exposure, there were marked increases in concentrations of total plasma protein and plasma creatinine whereas plasma inorganic phosphorus concentration significantly decreased. It is concluded that an increase in renal urea reabsorption during urea infusion in buffaloes kept in normal ambient temperature depends on the rate of urine flow which affect by an osmotic diuretic effect of electrolytes. The limitation of renal urea reabsorption in heat stressed animals would be attributed to an increases in either plasma pool size of nitrogenous substance or body metabolism.

• Fashion & Textile Research Journal
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• v.16 no.1
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• pp.167-174
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• 2014

The physical properties of textile materials and thermal physiological responses of the human subjects were evaluated with 4 different types of the army combat uniforms including US, German, Korean and general uniforms for this study. 8 male adults were used as the human subjects and the tests were done in the environmental chamber that was $25{\pm}0.1^{\circ}C$ of temperature, $65{\pm}5%$ of relative humidity and below 0.3 m/sec of air velocity. The test protocol consisted the rest period for 20 min., the exercise period for 20 min., the rest period for 20 min., the exercise period under wind condition for 20 min., and the recovery period for 20 min. The human subjects walked with 4.5 km/hr for 10 min., ran 7.5 km/hr for 10 min. during the first exercise period and walked and ran with the same speeds under 3.5 m/sec of the air velocity that simulated outdoor condition during the second exercise period. The test results of the study were as follows; The wind condition affected the skin and microclimate temperature of the human subjects lower compared to without wind condition, but had insignificant effect on the humidity control. The low air permeability of Korean uniform caused blocking the elimination of the humidity from the body and the regulation of body temperature. However, Korean uniforms could be the excellent one with the designs considering the ventilation of the uniforms and the textile fabrics with better air permeability.

• Proceedings of the ESK Conference
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• 1998.04a
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• pp.167-172
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• 1998

Methods of evaluating the physiological activity of the living body are EEG, EOG, Heart rate, and Rectal temperature, etc. In the study of Hagiwara and Araki(1993), they found positive correlations among performance test, physiological measurement, and subjective feeling measurement. Human alertness of pilot directly influences on the flight performance that accomplishes a lot of vigilance task and procedure execution in flight. Accordingly, this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applies. Throughout this experiment using performance thst, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05 .apaprox. 0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is ecpected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.93-96
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• 2009

The objective of this study is to analyze the insulation characteristics of the polylon hybrid fiber inserted high-strength RC beam and slab produced as a single body and the results of this study can be summarized as follows. In the spalling mechanism as an insulation characteristic, the slab of the single body type specimen shows an exposure in concrete covers at the center of slab and that leads to the spalling, which exposures reinforcing bars. In the case of the beam, the spalling was presented at several sections as a type of peel spalling before and after 10 minutes from the insulation test. Whereas, although the internal temperature history of concrete represents the highest range as 581℃ in the case of the center of the bottom of beam base, it can be considered that it satisfies the regulation of insulation certification.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.3
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• pp.405-415
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• 2019

This study examined the physiological and psychological effects of wearing a winter cap at rest in a cold environment. Seven older males participated in two separate trials: wearing a winter cap (CAP) and non-wearing a winter cap (CON). The experiment was conducted for 60 min in a climatic chamber (air temperature $7.8{\pm}0.3^{\circ}C$ with $43{\pm}2%RH$) with sedentary posture. Microclimate temperature at the vertex of the head was $6.88^{\circ}C$ higher in CAP compared to CON (p<.01). Microclimate humidity at the vertex was lower in CAP than in CON only during the last 5 min (p<.01). Skin temperature at the forehead in CAP was higher than in CON (p<.01). During the last 5 min, rectal temperature was higher in CAP than that in CON (p<.05). Unlike CAP, the heart rate in CON during the last 5 min decreased significantly compared to the initial 5 min (p<.05). Subjects also felt less cold on the head/face in CAP than that in CON (p<.01). The results indicate that wearing a cap for elderly males positively affected body temperature regulation and cardiovascular response in cold environments. The importance of wearing warm hats for elderly males in winter should be emphasized.