• Korean Journal of Applied Biomechanics
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• v.21 no.1
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• pp.97-105
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• 2011

The purpose of this study was to investigate the kinetic factors of Stefan holm's take-off motion and provide the technical data. Collected data of the subject(height: 181 cm, weight: 71 kg, record: 230 cm) were used for the last two strides and take-off phase. The results were as follows: The vertical impulse force was 2044.8 N which was 2.49 times and the anterior-posterior impulse force was -1306.4 N which was 1.88 times of the subject's weight. The take-off leg angular velocities($\omega_x,\;\omega_y$) were switched drastically from clockwise to count clockwise direction between two-step touchdown and take-off. The highest jerk of the take-off foot was 368.97 m/s3 during the two step take-off and the take-off foot made an impact to the ground with 1225.07 m/s3 during the one step touchdown.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1241-1246
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• 2014

Take-out robots used for handling of the plastic parts manufactured with the injection mold are usually the gantry type that consists of long and thin links. In this study, we want to evaluate the safety of the take-out Robot structure through finite element analysis. The take-out Robot is automated robot to transport from one location to another in the molded article. The take-out Robot structure has a 380 kilogram weight, a 1300mm width, a 670.5mm depth and a 670mm height. It confirms the equivalent stress and the deformation of the load and its own weight through weight analysis. It looks for the natural frequency of the take-out robot through modal analysis. It confirms the acceleration, the normal stress and the deformation about the natural frequency of the take-out robot through response analysis. Also It repeats the analysis by changing the structure of the take-out robot, to confirm the results and it is determined whether the safety of the structure. These analysis results are effectively used to reduce the vibration of the take-out robot.

• Journal of the Korean Home Economics Association
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• v.33 no.3
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• pp.207-223
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• 1995

This survey was carried out to investigate the correlationship between the nutrition knowledge scores and food habit of the mothers and food preference and other factors of the 272 elementary school children in Masan. The results were summarized as follows : 1. Children's most favorite food was fruits, but they dislike spicy vegetables and some fermented foods. Preferences of the male children to food groups such as protein, calcium and carbohydrate were significantly higher than those of the female children. 2. The rate of the children who take between-meal snacks 2 o 3 times a day was high and those children who skip breakfast take snacks more often. They prefer to eat fruits, dairy products and cakes as their snacks. The body weight of the children who take snacks more frequently was rather lower. 3. As the mother's nutrition knowledge scores rise, so do those of food habit scores. The nutrition knowledge scores go up according to the education degree of the mothers, but the food habit scores seem to have little to do with their education degree. The nutrition knowledge scores of the working mothers were lower than those of the non-working mothers. 4. There was strong positive correlation between the food preference on the food group and those on the other food groups of the children. As the food habit scores of the mothers rise, the children prefer to take calcium and carbohydrate group. Those who take more fat showed higher body weight.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.1
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• pp.39-55
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• 2003

This study was conducted to investigate the effect of an uncooked powdered food(UPF) on the weight loss and changes of the biochemical nutritional status for 20 overweight and 26 obese women in Iksan area. We just replaced common breakfast and dinner of the subjects with UPF. Their dietary intake status was evaluated by 24-hour recall method. Also anthropometric and biochemical measurements before and after the UPF program were estimated. The intake of energy, lipid and protein decreased and the quality of meals improved as people started to take UPF. Due to the energy loss by taking UPF, weight and body fat decreased significantly. The percentage of the body fat was high among the weight lost, from which we judged that the process of losing weight was successful. It is hard to predict whether weight loss will occur to people who are already in shape or not, but if overweight and obesity people regularly take UPF instead of other food products, we assume that UPF will help lessening the body fat. The most positive change among biochemical changes by taking UPF was the decrease of serum lipid contents. When overweight and obesity women replaced two out of three meals with UPF for 3 month period, no significant nutritional problems occurred. It seems that the 12weeks of UPF program used in this study was effective in improving anthropometric indices without producing the deficiency of iron or other susceptible nutrients.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.3
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• pp.56-66
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• 2013

Weight reduction of the VTHL / TSTO type of the reusable launch vehicles using RBCC engines are investigated. To predict weight and thrust of the vehicles, equations of motion are analyzed. Analysis results are compared with specifications of existing launch vehicles for validations. For the mission of inserting 2.5 ton payload to 200 km circular orbit, the case A, which uses the RBCC engine in the 1st stage shows smaller weight than the case B, which uses the RBCC engine in the 2nd stage. The weight of the case A shows only 25.8% of a existing rocket launch vehicle's weight.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.8
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• pp.404-410
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• 2006

Toward the practical applications, on operation of conduction-cooled HTS SMES at temperatures well below 40[K] should be investigated, in order to take advantage of a greater critical current density of HTS and considerably reduce the size and weight of the system. In order to take advantage of a greater critical current density of high temperature superconducting (HTS) and considerably reduce the size and weight of the system, conduction-cooled HTS superconducting magnetic energy storage (SMES) at temperatures well below 40[K] should be investigated. This work focuses on the breakdown and flashover phenomenology of dielectrics exposed in air and/or vacuum for temperatures ranging from room temperature to cryogenic temperature. Firstly, we summarize the insulation factors of the magnet for the conduction cooled HTS SMES. And Secondly a surface flashover as well as volume breakdown in air and/or vacuum with two kind insulators has been investigated. Finally, we will discuss applications for the HTS SMES including aging studies on model coils exposed in vacuum at cryogenic temperature. The commercial application of many conduction-cooled HTS magnets, however, requires refrigeration at temperatures below 40[K], in order to take advantage of a greater critical current density of HTS and reduce considerably the size and weight of the system. The magnet is driven in vacuum condition. The need to reduce the size and weight of the system has led to the consideration of the vacuum as insulating media. We are studying on the insulation factors of the magnet for HTS SMES. And we experiment the spacer configure effect in the dielectric flashover characteristics. From the results, we confirm that our research established basic information in the insulation design of the magnet.

• Journal of Nutrition and Health
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• v.36 no.1
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• pp.49-63
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• 2003

The purpose of this study was to obtain the nutritional values and objective data of uncooked powdered food (UPF) in korea. We interviewed 27 healthy female subjects aged over 25 years living in the lksan area. We just replaced common breakfast and dinner of the subjects with UPF. Their dietary intake status was evaluated by 24-hour recall method. Their body compositions were measured using body fat analyzer. Also we conducted hematological and clinical analysis of blood. The intake of energy, lipid and protein has decreased as people started to take UPF, but the intake of vitamins and minerals has increased. The quality of meals has improved after taking UPF. Due to the energy loss by taking UPF, weight and body fat gradually lessened. Among the lost weight the percentage of the body fat was high and we judged that the process of losing weight was successful. It is hard to predict whether weight loss will occur to people who are already in shape or not, but if overweight and obesity people regularly take UPF instead of other food products, we assume that UPF will help lessening body fat. The most positive change among biochemical changes by taking UPF was decreasing of serum lipid contents. The concentrations of total cholesterol and LDL-cholesterol gradually decreased and decreased intently after 12weeks. Serum HDL-cholesterol gradually increased and serum triglyceride showed gradual decrement. When healthy adult women replaced two of three meals with UPF for 3months, we were able to see some useful changes like decrement of body fat and serum lipid control and during this 3month period, no significant nutritional problems occurred. Complete judgement on UPF may be difficult with these conclusions but if people take a nomal meal once and replenish iron from taking UPF twice a day, we assume that replacing UPF with regular meal not be a problem in nutritional status. If other experiments on the effects of UPF proceed, we believe that those experiments will be very helpful in judging the nutritional value of UPF. (Korean J Nutrition 36(1) : 49-63, 2003)

• Journal of Nutrition and Health
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• v.36 no.6
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• pp.589-602
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• 2003

This study was designed to investigate the effects of weight reduction and changes in serum lipid composition using a commercial uncooked powdered food (UPF) diet on 27 obese hyperlipidemic women over a period of 12 weeks. We replaced the standard breakfast and dinner of each of the subjects with UPF. Their dietary intake status was evaluated by 24-hour recall method. Their body compositions were measured using a body fat analyzer. Also, we conducted hematological, clinical and lipid profile analyses of their blood. Their intake of energy, lipid and protein significantly decreased as the subjects started to take UPF, but their intake of vitamins and minerals, other than iron, increased. Due to the energy intake decrease, the subjects' weight, body fat and waist circumference significantly decreased. Among the lost weight the percentage of the body fat was high. We judged that this process of losing weight was successful in obese hyperlipidemic women. Serum HDL-cholesterol gradually increased and serum total-cholesterol, LDL-cholesterol, triglyceride levels showed gradual decreases. When obese hyperlipidemic women replaced two of three meals with UPF for 3 months, we were able to see useful changes like decreased body fat and serum lipid. Complete judgment on the usefulness of UPF may be difficult but if people take a standard meal once a day and replenish their iron by taking UPF twice a day, we assume that replacing UPF with balanced regular meal not be a problem in nutritional status. Our results show that UPF is effective in the diet therapy of obese hyperlipidemic women.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.1
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• pp.13-20
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• 2022

Aircraft weight is an important factor affecting performance and fuel efficiency. In the conceptual design stage of the aircraft, the process of balancing cost and weight is performed using empirical formulas such as fuel consumption cost per weight in estimating element weight. In addition, when an airline operates an aircraft, it promotes fuel efficiency improvement, fuel saving and carbon reduction through weight management activities. The relationship between changes in aircraft weight and changes in fuel consumption is called the cost of weight, and the cost of weight is used to evaluate the effect of adding or reducing weight to an aircraft on fuel consumption. In this study, the problems of the existing cost of weight calculation method are identified, and a new cost of weight calculation method is introduced to solve the problem. Using Breguet's Range Formula and actual flight data of the A350-900 aircraft, two weight costs are calculated based on take-off weight and landing weight. In conclusion, it was suggested that it is reasonable to use the cost of weight based on the take-off weight and the landing weight for other purposes. In particular, the cost of weight based on the landing weight can be used as an empirical formula for estimating element weight and optimizing cost and weight in the conceptual design stage of similar aircraft.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.142-143
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• 2008

In the present work, high-speed video images of the ground take-off flight of a live butterfly were captured and their dynamic motions during the first full-stroke were analyzed. To capture the dynamic images of the take-off motion, the experimental setup consisted of a high-speed camera, a Xenon lamp as a light source and a transparent chamber of $15^W{\times}15^L{\times}17^H$ $cm^3$ in physical size. The ambient temperature and supplementary lighting devices were precisely controlled. The weight and wing span of the butterfly tested in this study was 104 mg and 63.14 mm, respectively. The ground take-off images were captured with 4000 fps with a spatial resolution of (1024${\times}$512) pixels. The period of the first full-stroke was 80.5ms and the flapping speed of downstroke was 2 times faster than that of upstroke. As a result, butterflies used the fling and near-clap motion to generate lifting force and an interesting take-off behavior of early pronation and downstroke was observed.