• Journal of Advanced Marine Engineering and Technology
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• v.24 no.4
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• pp.427-434
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• 2000

In tradition, there have been two kinds of drying methods, which are sun drying and artificial drying. The sun drying method which has been adopted traditionally has been replaced by the hot-air drying method which is one of the most general methods of artificial drying, with its simple drying system, low initial cost of drying plant, and easy operating method. But the hot-air drying method has some defects; (1) much energy loss happens due to the discharge of hot air during the drying process, (2) control of drying rate is not easy on account of changing relative humidity of inlet air for uniform hot air temperature, (3) high temperature of foods in drying process brings about the production of low-grade drying products. Vacuum drying takes advantage of energy saving and mass production because it reduces the drying time by increasing the drying rate under low temperature condition. The aim of this paper is to develop the low temperature vacum dryer, with low initial investments and operating costs, easy operating method and trouble-free operation.

• Journal of Korean Medicine Rehabilitation
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• v.15 no.1
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• pp.109-126
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• 2005

Objectives : This study is to examine the influence of exorcise program to body shape and body composition of women. Exercise program is composed muscular resistance exercise and aerobic exorcise with 70min/time, 5day/week for 4weeks and designed for the reinforcement of muscular strength and the decease the decrease of obesity. Methods : The subjects of this study are 26 females who are from twenty until thirty-nine years old and are divided into two groups according to Obese Rate. normal weight group is 18 females under a BMI of 23 and overweight group is 8 females over a BMI of 23. we measured body compositon and body shape with body composition analyzer(inbody 3.0) measured body compositions are body weight, Lean body mass, base metabolic rate, body fat, %body fat, waist hip ratio, body mass index. measured 6body shade are upper arm circumference, chest circumference, waist circumference, hip circumference, thigh circumference. the measurements had been taken before exercise of each group, after 4 weeks, after 8 weeks, after 12 weeks. Body compositon and body shape of the measured data were analyzed by two-way repeated ANOVA followed by Dunnett's Post hoc test using SPSS. Differences were considered significant at p<0.05. Results and Conclusions : The weight was reduced at a significant level in overweight group after 4 weeks. Body fat percent was reduced at a significant level in normal group alter 4 weeks and overweight group after 8 weeks. Waist-hip ratio was reduced at a significant level in normal and overweight group after 4 weeks. Lean body mass and body metabolic rate were reduced but did not satisfy statistical significance. Circumference of all body parts showed an decrease after 12 weeks exercise program. Upper Arm, Chest, Waist, Hip Circumference were reduced at a significant level in overweight group after 4 weeks, but In normal group only Waist Circumference was reduced at a significant level after 4 weeks. Aerobic and Circuit weight training for 12 weeks reduced body weight and body fat percent, waist circumstance statistically significant without loss of lean body mass and body metabolic rate. Also these change was more effective in overweight group than in normal group.

• Fire Science and Engineering
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• v.33 no.4
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• pp.35-40
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• 2019

In this study, the mass flow rate of the heat release rate equation, which is the major factor of the oxygen consumption method, was analyzed for the fundamental investigation of the cone-calorimeter (5 m length and 0.3 m diameter). The shapes of a completely empty inside, 3 mm pore diameter mesh and pore diameter 10 mm honeycomb with 0.76 porosity were constructed using the cone-calorimeter. To calculate the mass flow rate, four bi-directional probes and thermocouples were installed in a uniform position in the vertical direction of flow. The velocity gradient and flow perturbation were measured from the increase in Reynolds number. As the flow capacity increased, the speed gradient increased in all three shapes relative to the turbulence intensity. In addition, the deviation of extended uncertainty to the mass flow was completely low in the order of empty space, mesh (d_p = 3 mm) and honeycomb (d_p = 10 mm and 𝜖 = 0.76) at the 95% confidence level. The results can be used in designs to improve the flow stability of the cone calorimeter.

• Journal of Korean Public Health Nursing
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• v.27 no.1
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• pp.102-112
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• 2013

Purpose: The purpose of this study was to determine the effects of a weight loss program administered through a smart phone application on body composition and obesity in adolescents. Methods: This study applied a 6-week weight loss program with dietary education, exercise therapy, and behavior modification therapy from 4 June 2012 to 20 July 2012. The collected data were analyzed by descriptive statistics and the Wilcoxon signed rank test using the SPSS WIN 18.0 program. Results: After the 6-week program, the average weight of the subjects was reduced from 75.96kg to 74.41kg (Z=$-3.994^p$, p<.001), while the body mass index (BMI) decreased from 29.23 to 28.60 (Z=$-3.980^p$, p<.001), and the obesity index decreased from 38.45% to 35.59% (Z=$-3.977^p$, p<.001). The percentage of body fat decreased from 32.45 to 31.92 (Z=$-3.947^p$, p<.001), and the rate of skeletal muscle growth increased from 26.06% to 26.58% (Z=$-3.822^p$, p<.001). Conclusion: A weight loss program using a SNS (social network service) application, with dietary education, exercise therapy, and behavior modification therapy can reduce obesity and impact body composition in a short-term. Therefore, the utilization of the SNS application can be used to effectively enhance the management of adolescent obesity.

• The KSFM Journal of Fluid Machinery
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• v.8 no.4 s.31
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• pp.39-47
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• 2005

The present study has been performed to investigate the influences of rectangular fins on heat transfer in an impingement/effusion cooling system with crossflow. To simulate the impingement/effusion cooling system with initial crossflow, two perforated plates are placed in parallel and staggered arrangements with a gap distance of 2 times of the hole diameter. The crossflow passes between the plates, and various rectangular fins are installed on the plates. Reynolds number based on the hole diameter is fixed to 10,000 and the flow rate of crossflow is changed from 0.5 to 1.5 times of that of the impinging jet. A naphthalene sublimation method is used to obtain the heat/mass transfer coefficients on the effusion plate. Also to analyze the flow characteristics, a numerical calculation is performed. When rectangular fins are installed, the flow and heat transfer pattern is changed greatly from the case without fins. In the injection hole region, the jet impinges on effusion plate without deflection and wall jet spreads symmetrically. In the effusion region, the crossflow accelerates due to the decrease of cross-sectional area in the channel. Local heat/mass transfer coefficients are enhanced significantly compared to the case without fins. As the blowing ratio increases, the effect of rectangular fins against the crossflow becomes more significant and then the higher average heat/mass transfer coefficients are obtained than the case without fins. However, the increase of blockage effect gives more pressure loss in the channel.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.1955-1962
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• 2020

In a sudden shutdown of primary pump or coolant loss accident in a marine nuclear power plant, the primary flow decreases rapidly in a transition process from forced circulation (FC) to natural circulation (NC), and the lower flow enters the steam generator (SG) causing reverse flow in the U-tube. This can significantly compromise the safety of nuclear power plants. Based on the marine natural circulation steam generator (NCSG), an experimental loop is constructed to study the characteristics of reverse flow under middle-temperature and middle-pressure conditions. The transition from FC to NC is simulated experimentally, and the characteristics of SG reverse flow are studied. On this basis, the experimental loop is numerically modeled using RELAP5/MOD3.3 code for system analysis, and the accuracy of the model is verified according to the experimental data. The influence of the flow variation rate on the reverse flow phenomenon and flow distribution is investigated. The experimental and numerical results show that in comparison with the case of adjusting the mass flow discontinuously, the number of reverse flow tubes increases significantly during the transition from FC to NC, and the reverse flow has a more severe impact on the operating characteristics of the SG. With the increase of flow variation rate, the reverse flow is less likely to occur. The mass flow in the reverse flow U-tubes increases at first and then decreases. When the system is approximately stable, the reverse flow is slightly lower than obverse flow in the same U-tube, while the flow in the obverse flow U-tube increases.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.2
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• pp.94-100
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• 2022

A study was conducted to significantly increase the heat transfer area by simultaneously burying the excel pipe in the floor and wall of a container house, thereby greatly reducing the initial heating time. In addition, a small hot water boiler suitable for the heating load of a small container house with a maximum area of 6 m² was studied. A wall-mounted hot water boiler was developed as a result of the study. When a hot water boiler is installed outdoors for heating, heat radiation energy is lost in winter from the hot water boiler and hot water pipe due to the low temperature. We propose an approach through which the energy loss was greatly reduced and the temperature of hot water increased in proportion to the operating time. Moreover, as the mass flow rate of the hot water flowing inside the excel pipe increased, the temperature of the hot water decreased. The temperature of the wall and floor surfaces of the container house increased in proportion to the increase in the mass flow rate of hot water flowing inside the excel tube. Natural convection heat transfer was realized from the wall and floor surfaces of the container house, and the heat transfer area was increased by a factor of 3 with respect to heat transfer area limited to the floor by the existing hot water panel. As a result, the initial temperature increase rate was much higher because of the larger heat transfer area.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.41-48
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• 2000

Mass loss and dynamics of mineral nutrient during decomposition of deciduous leaves and 3 species of needles were investigated for 38 months from October in 1992 to November in 1995 in Kwangneung, Korea. After 38 months, the remaining mass of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 16.2%, 29.8%, 33.5% and 53.9%, respectively. The decay rate (k) of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 0.61, 0.40, 0.37, $0.21yr^{-1}$, respectively. The lowest decay rate in fir needle might be, in part, due to low N concentration. N concentration of the decomposing litter increased during the experimental period except for P. rigida. Deciduous leaves showed a short immobilization period during the early stage of decomposition, and big-cone pine and pitch pine had no immobilization period. However, there was no net N mineralization in fir litter. P increased during the experimental period for all litter. Except for deciduous leaves, there was no net mineralization period. In case of deciduous leaves, however, remaining P after 38 months was 53% of the initial P capital. Remaining cations of the decomposing litter after 38 months were lower than those of initial contents.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.219-222
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• 2005

Recently, the interest of the engine capacity and environment of the atmosphere is increasing, so the researches for the engine capacity have been conducted for a long time. But the internal environment of an automotive engine is very severe. A piston is exposed to combustion gas of over $2000^{\circ}C$ and strong friction is occurred by high speed motion in the cylinder. The fraction between piston and wall of the cylinder causes the increase of temperature in the engine. The temperature of the engine has an effect on the engine capacity. If the temperature is high, the capacity of the engine is low. So we have to maintain the optimum temperature. To maintain the optimum temperature, the enough flow rate of the engine oil is needed. The oil jet is used to control the flow rate of the engine oil and supply the engine oil to the piston and cylinder. The purpose of this study is to check the mass flow rate of the engine oil and the characteristics of internal flow of the oil jet. Flow pattern of the engine oil is very important because it concludes the loss in the oil jet. This study is the previous research about the oil jet and we will consider the movement of the ball check valve to get more accuracy result.

• Journal of Haehwa Medicine
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• v.19 no.2
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• pp.179-186
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• 2011

Obhectives : The purposes of this study are to evaluate the effect of zymolysis-dietotherapy with herbal medicine on the obesity in Sasang constitution Methods : Seventy five patients were classified into four obesity groups by Body Mass Index, and four Sasang constitution groups by QSCC. Weight, body fat, body fat rate, BMI were compared in each group. Results : Weight, body fat, body fat rate, BMI were decreased significantly in all groups. There was statistically significant difference in the loss of weight, BMI between Taeumin and others. Decrement of body fat rate is not statistically significant between Taeumin and others. Conclusions : In conclusion, it was proved that zymolysis-dietotherapy with herbal medication is effective on the obesity treatment of all Sasang constitution groups. And the group of Taeumin lose more weight.