• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.108-113
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• 2002

This paper presents a multi-step structural design optimization method fur machine tool structures using a genetic algorithm with dynamic penalty. The first step is a sectional topology optimization, which is to determine the best sectional construction that minimize the structural weight and the compliance responses subjected to some constraints. The second step is a static design optimization, in which the weight and the static compliance response are minimized under some dimensional and safety constraints. The third step is a dynamic design optimization, where the weight static compliance, and dynamic compliance of the structure are minimized under the same constraints. The proposed design method was examined on the 10-bar truss problem of topology and sizing optimization. And the results showed that our solution is better than or just about the same as the best one of the previous researches. Furthermore, we applied this method to the topology and sizing optimization of a crossbeam slider for a high-speed machining center. The topology optimization result gives the best desirable cross-section shape whose weight was reduced by 38.8% than the original configuration. The subsequent static and dynamic design optimization reduced the weight, static and dynamic compliances by 5.7 %, 2.1% and 19.1% respectively from the topology-optimized model. The examples demonstrated the feasibility of the suggested design optimization method.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.1
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• pp.71-86
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• 1997

The 297 middle school girls in Inchon were devided into three groups according to body mass index(BMI), the under weight group, the normal weight group and obese group to find out relationship between their food habits, food preference, and obesity. The average height and weight are 159.40cm, 67.02kg for obese group, 158.17cm, 39.11kg for under weight group, 156.93cm, 53.78kg for normal weight group. Obese group feels that they are healthy and fat, and their parents are fat also than the other groups. Obese group took more exercise. Total Food habits scores of obese group were lower than the other two groups. In terms of supper, bedtime-smack, unbalanced diet, balanced intake of five basic food groups obese group had lower scores. Especially, intake of carbohydrate, protein, milk group were irregular. There is no significant different in size of meal, overeating eating speed. The preferences of fast food, instant food, high caloric density food were lower in obese group than in the other two groups. The mother of obese group prepared meals according to food composition and prepared little snakes.

• Korean Journal of Health Education and Promotion
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• v.21 no.2
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• pp.133-146
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• 2004

Purpose： The purpose of this study was to investigate the actual conditions of obesity, and the factors related to children's obesity. Method： The subjects were 568 students (5th, 6th grades) of ten elementary schools in a small city of about 350,000. Subjects self-reported after being instructed by researchers to identify health habits and attitudes toward obesity. The Rohrer index was calculated by using annual physical examinations preformed by the schools. Result： 17.5％ of the subjects were under weight, 22.2％ were overweight, and 60.3％ were normal. In girls, the under weight group was much larger, in boys the overweight group was larger. 46.2％ of overweight children had a familial tendency to obesity. 60.6％ of boys and 60％ of girls were on a diet in order to improve their looks or to prevent ridicule from mends. On average, one-third of the subjects misunderstood their own weight level. Subjects spent 3-4hours on weekdays, and over 6hours on the weekend watching TV or using personal computers. The overweight group enjoyed eating meat, fish, beans and vegetables, while the normal group tended to prefer fruit. Conclusion： Health education programs which guide elementary school students to form better health habits, more accurate perceptions of their own body weight, and better attitudes toward obesity and which make students aware of the importance of exercise, a healthy diet, and reducing time spent in front of TVs and computers may help them to keep at their appropriate weight.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.69-73
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• 1991

This experiment was carried out in order to study the effect of nitrogen fertilization on the growth of Colonial bentgrass and thatch accumulation under no removing clipping residues. Nitrogen fertilization was applied as 4 levels, 10, 20, 25 and 20gN/m$^2$, respectively. The results were as follows : 1.Response of plant length and dry weight of thatch to N fertilization were significant differences between N levels. It suggested that N fertilization with no clipping residues greatly affected to the growth and thatch accumulation of colonial bentgrass.2.Plant length, the dry weight of clipping residues and coverage were obtained the highest values at 20g N. It was assumed that 20gN/m$^2$ is the limiting N level to obtain the favorable growth of Colonial bentgrass. 3.The dry weight of thatch and lignin content were increased with high nitrogen fertilization level. 4.The dry weight of thatch indicated positive significant correlation with lignin content. 5. The dry weight of thatch per N(THg/N) at 20g~25g/m$^2$ levels were obtained the lowest values than of other levels of N. It may be due to the stimulating of microbial activity by adequate to N fertilizers which increased mineralization of thatch.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1616-1623
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• 2008

This study was conducted to determine the effect of hot environment and dietary crude protein level (CP) on performance, carcass characteristics, meat visual quality, muscle chemical composition and malondialdehyde (MDA) concentration of tissues in broilers. Two hundred and sixteen 21-d old Arbor Acre broilers were used in a $4\times3$ factorial arrangement and randomly reared in 4 environmental chambers and fed on 3 diets with different CP levels for 3 weeks. The results showed: (1) when air temperature (AT) rose to $33^{\circ}C$, average daily feed intake, average daily gain, carcass weight, right breast meat weight, left thigh and drumstick meat weight decreased (p<0.05) and feed conversion rate decreased (p<0.05), but the ratio of carcass to live weight and of left thigh and drumstick meat weight to carcass weight increased (p<0.05). (2) There were significant differences in pH and shear force in breast meat, and shear force, L* and a* in thigh meat (p<0.01 or 0.05) among hot environments. Dietary CP level tended to affect breast meat pH and pH and L* of thigh meat (p<0.06 or 0.09). Compared to the normal temperature ($22^{\circ}C$), low temperature ($15^{\circ}C$) and hot humid (AT $33^{\circ}C$, relative humidity (RH) 80%) treatments significantly (p<0.05) decreased the tenderness of thigh meat. L* and a* value in thigh meat under high temperature treatments, regardless of RH, were higher (p<0.05) than those under normal temperature. (3) Protein content in breast and thigh meat of broilers fed under high temperature ($33^{\circ}C$) was lower (p<0.05) than that under $22^{\circ}C$, but fat content had an adverse change. High temperature ($33^{\circ}C$) increased the moisture of breast meat significantly (p<0.05). Protein content in breast meat increased significantly (p<0.05), in which fat content had an adverse change (p<0.05), when the dietary protein rose. (4) MDA concentration in liver and breast meat under hot humid (AT $33^{\circ}C$, RH 80%) treatment increased markedly (p<0.05). (5) High humidity could sharpen the bad effect of high temperature on performance, carcass yield and choice cuts, crude protein and moisture content in breast meat. It was concluded that a hot environment could affect the performance and meat quality of broiler chicks more significantly than CP level and that high humidity would aggravate the bad influence of high temperature on the broiler.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.4 s.44
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• pp.417-430
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• 1992

To examine the effects of clothes upon human's physiological adaptation to the changes of climatic conditions, clothing weight was examined. The results are as follows; 1. According to the change in temperature, the total, upper and outer clothing weight showed remarked change. Clothing weight change was greatest between the July and October, the change was greater in the coast land and the girl students. 2. The clothing weight tends to be light under outdoor in both regions in all seasons except in July, it is remarked in inland and December. 3. The correlation between $R\"{o}hrer$ Index, Body Fat and clothing weight was recognised to be significantly reversed. 4. Positive correlation between health conditions and clothing weight was recognized in December 5. The correlation between exercise hours and clothing weight was negatively significant in December.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.462-470
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• 2016

The locking load of a conventional manhole depends on the weight of its cover. Locking-type manhole structures with a special locking mechanism were recently developed to prevent accidents such as stolen cover, away cover from a frame. The weight of the manhole structure can be reduced under structural safety because the locking force of a locking-type manhole is greater than the weight of the cover. A light-weight manhole cover is developed in this study by using a finite element stress analysis and the design of experiments. Static stress analysis and fracture experiments are also conducted to analyze the states of the initial product. The optimum light-weight manhole cover considering manufacturing molds is developed and tested. Consequently, the weight was found to reduce by 16%. In addition, the fracture load increased by 38%.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.87-99
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• 1973

The purpose of this project is offering fundamental and proper informations for the better health control and personnel management of the enlisted men of Marine corps in Korea. Survey has been done under 1,001 marine enlisted men for the purpose of understanding their condition of physique, vital capacity, and bodily strength. 1. Under the subject of physique, 7 items, body weight, chest-girth, relative body weight, relative chest-girth, Vervaeck index, and Roehrer index are listed, and under the subject of vital capacity, BTPS vital capacity and percent predicted vital capacity are listed, and under the subject of bodily strength, 7 items, grasping power, chinning-up, throwing a hanp-grenade, forward jumping, sitting-up, 100 meter sprinting, are listed. The total items are 16 and mean score of each one is as follow. 1)Physique : a. Height : $$168{\pm}0.15cm$$ b. Body weight : $$62.7{\pm}0.17kg$$ c. Chest-girth : $$91.4{\pm}0.16cm$$ d. Relative body weight : $$37.2{\pm}0.09$$ e. Relative chest-girth : $$54.3{\pm}0.10$$ f. Vervaeck index : $$91.6{\pm}0.15$$ g. Roehrer index : $$1.31{\pm}0.003$$ 2) Vital capacity : a. BTPS vital capacity : $$4470{\pm}20cc$$ b. % Predicted vital capacity : $$150{\pm}5.1%$$ 3) Bodily strength : a. Grasping power : $$41.4{\pm}0.26kg$$ b. Chinning-up : $$5.7{\pm}0.10$$ c. Throwing a hand-grenade : $$39.7{\pm}0.20m$$ d. Forward jumping : $$214{\pm}0.58cm$$ e. Sitting-up : $$19.1{\pm}0.25$$ f. Pushing-up : $$22.1{\pm}0.18$$ g. 100 meter sprinting : $$16.1{\pm}0.04sec$$. 2. Comparative analysis has been done about the conditional classes of marine enlisted men with the results of above mentioned 16 items. 7 classes according to the branches, 3 according to the ranks, 9 according to tile length of service are adopted respectively.

• Korean Journal of Medicinal Crop Science
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• v.22 no.2
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• pp.154-159
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• 2014

This study was carried out in order to investigate the early growth and root development characteristics of Atractylodes japonica container seedling. Experiment was performed by light intensity (100%, 60%, 25% and 10% of full sunlight). Height was surveyed well under 25% of full sunlight (overall 11.013.0%). Root collar diameter was the highest in the full sunlight (7.52 mm). It was the highest fresh weight (1.52 g, 0.92 g, 0.90 g and 3.34 g) under 25% of full sunlight, root dry weight was getting higher in the higher light level and the highest in the full sunlight (0.13 g). Total root length, root project area, root surface area and root volume were the highest under 25% of full sunlight (434.7 cm, $17.4cm^2$, $54.7cm^2$, $0.55cm^3$, respectively) and the lowest under 10% of full sunlight. As a result of surveying the whole experiment, A. japonica is judged nicely by maintaining 25% of full sunlight, excepting 10% of full sunlight. And light levels during the early growth are overly important to improve early growth.

• Textile Coloration and Finishing
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• v.8 no.1
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• pp.64-72
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• 1996

To develop a scouring method for the high-grade quality and the high value added of flax for spinning, it was measured and analyzed weight loss and degree of injury with change of scouring concentration, time, temperature and pH. We got the f ollowing results; Firstly, in case that flax was scoured at a fixed condition, the weight loss and degree of injury of scoured flax under the no-cutting condition were lower than that of scoured flax under the cutting condition. Secondly, when flax was scoured with $Na_{2}CO_{3}$, it was obtained that the higher weight loss and degree of injury and weight loss with the increase of scouring time and condition. The degree of injury was lower than any other under the treatment condition of 4% $Na_{2}CO_{3}$concentraion for 2 hours. Finally, when alkaline scoured flax was rescoured by pectinase, enzyme activation effect was the most active under the treatment condition of pH 4 for 2 hours. The scouring effect was better than that of alkaline scouring only.