• Transactions of Materials Processing
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• v.13 no.8
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• pp.710-715
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• 2004

The effect of microstructural features on ductility of cold drawn pearlitic steels containing 0.52 ～ 0.92 wt%C was investigated. During wire drawing, reduction of area (Rh) increased initially with the progressive realignment of randomly oriented cementite, showed a maximum peak due to the completion of the alignment of most cementite, and decreased with thinning or fragmentation of the aligned cementite. Among factors on ductility, cementite thickness was found to be the most dominant microstructural feature for Rh of drawn pearlitic wires, regardless of transformation temperature and carbon content in steels.

• Water for future
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• v.19 no.2
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• pp.157-166
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• 1986

The objective of this study was to determine the best representative synthetic unit hydrograph that is applicable to ungaged small watershed. A typical unit hydrograph was established with the actual data from a small watershed. Four currently well-known methods for analyzing ungaged small watershed, including Snyder's, Clark's S.C.S. and Nash methods, were evaluated with the data from the same small watershed. The following observations were noted from the analysis of four methods. The Snyder's method yielded the similar peak discharge value as the typical unit hydrograph. With co-ordinates of three discharge values, i.e. 25%, 50% and 75% of peak discharge, were not adequate for deriving a typical unit hydrograph in ungaged small watershed. With Clark's method there shall be some way of obtaining the exact base length of time area diagram and isochrone of each reach of the stream. With Nash method peak discharge and base flow time are affected by the storage constant and gamma function argument; therefore, for deriving a more reliable and workable unit hydrograph one needs to select for the better estimation of storage constant and gamma function argument. In S.C.S. method peak discharge is directly related to the watershed area and inversely related to the time of peak diacharge. Therefore area with faster peak discharge yielded the higer peak discharge value. Although the peak discharge value obtained frome the S.C.S. method higher than the value obtained from the unit hydrograph developed from the actual data, this method contains a number of advantageous factors. The peak discharge value and the time of peak discharge can be claculated easity from the morphological characteristics of the watershed, and in S.C.S method co-ordinates of the unit hydrograph can be calculated easily from that of the dimensionless unit hydrograph. When the four currently used methods were evaluated with a typical unit hydrograph obtained from the actual data, the S.C.S method was show to be the best method in deriving a synthetic unit hydrograph for ungaged small watershed.

• Journal of Community Nutrition
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• v.6 no.3
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• pp.117-120
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• 2004

Objective : To get a better understanding of obesity and etiological factors of obesity among school children. Methods : We have conducted a questionnaire survey of 4542 (2395male and 2147female) age from 7-15 in Shanghai School District to study their 24h nutrition intakes ; we have asked all our survey participating students to take a physical exam and body mass index measurement to determine the morbidity of obesity. Common statistic method was used in analyzing the data. Results : The result shows an over all morbidity (boys and girls) of $12.3\%$ among the students we have studied. Our research shows that boys have a higher rate of morbidity of obesity $17.1\%$ vs. $7.0\%$ for girls. The morbidity for boys starts under age 10, reaches the peak at age 10 ($24.3\%$), then declines after age 11 ; as for girls the morbidity starts at under age 9, reaches the peak at 9, and then declines after 10. Our study also indicates that the daily nutrition intake of protein, fat and carbohydrate by the students have satisfied Chinese Dietary Reference Intakes (DRIs), while the daily intakes of calcium, iron, zinc, and vitamin C are below the $80\%$ of the DRIs suggested value. For students who are obese, our study shows that their average daily intakes of calories and protein have reached $90\%$ of the suggested value by the RNI while the intakes of calcium, iron, and zinc are far below standards. Furthermore, our research shows that the obese students usually intake more calories, proteins and vitamin $B_1$, but less for iron and calcium compared to the normal students. Some other factors such as the education and occupation of the parents, especially the mother, the family history of obesity and the eating habits are important factors that should be closely watched. Conclusion : The morbidity of obesity among boys is higher than girls. Obesity is closely related to the family history, the diet habits and the life styles.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.3
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• pp.191-197
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• 2017

Light detection and ranging (LiDAR) is one of the most efficient technologies to obtain the topographic and bathymetric map of coastal zones, superior to other technologies, such as sound navigation and ranging (SONAR) and synthetic aperture radar (SAR). However, the measurement results using LiDAR are vulnerable to environmental factors. To achieve a correspondence between the acquired LiDAR data and reality, error sources must be considered, such as the water surface slope, water turbidity, and seafloor slope. Based on the knowledge of those factors' effects, error corrections can be applied. We concentrated on the effect of the seafloor slope on LiDAR waveforms while restricting other error sources. A simulation regarding in-water beam scattering was conducted, followed by an investigation of the correlation between the seafloor slope and peak timing of return waveforms. As a result, an equation was derived to correct the depth error caused by the seafloor slope.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.323-329
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• 2010

Physical damages on fruits may be caused by shock and vibration inputs that transmitted from the transporting vehicle through the packaging and cushioning materials to the fruit. In this study, both half sine shock test and trapezoidal shock test were performed by MIL-STD-810F specification in order to investigate and represent the shock response properties such as peak acceleration and shock amplification factors of the pear according to packaging and cushioning materials for optimal packaging design during transportation. Shock excitation data that had been measured on the vehicle operating on the real road were used. Shock response properties measured by half sine shock test were smaller than those measured by trapezoidal shock test. Results represent that corrugation shapes and thickness can significantly affect the cushioning performance than the paper configurations of cushioning pad and showed that fruits may be damaged seriously while transported on the unpaved road without the properly cushioned packaging practices.

• Journal of Chest Surgery
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• v.26 no.3
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• pp.170-179
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• 1993

Three hundred consecutive adult patients having cardioaortic surgery under the cardiopulmonary bypass for a variety of cardioaortic lesions were evaluated retrospectively for postoperative hyperbilirubinemia[above 5mg/100ml].We found twenty eight patients with postoperative hyperbilirubinemia and divided them into two groups according to the postoperative day of peak s-bilirubin .Group A was the patients with a peak s-bilirubin level within three days ,and group B above three days postoperatively.Group B was divided into group S[survive] and group D[death] . We had compaired the survival & death group and observed the correlation between the decreasing tendency of postoperative s-bilirubin & the nutrition per os in group B. The incidence of postoperative hyperbilirubinemia,as defined by a s-bilirubin concentration of 5.0mg/100ml or greater,was 9.3%.The mortality rates of group A & B were 0.0% and 35.7% respectively.Important contributing factors between group A & B were the age,duration of ICU,Max.DOAB[maximum dose of catecholamine used],amount of blood transfused during or shortly after surgery and preoperative pulmonary hypertension[main pulmonary artery pressure > 30mmHg] and backward heart failure. The risking factors of group D compared to group S were as follows the age,preoperative & postoperative SGOT[serum glutamic-oxaloacetic trasaminase],postoperative total & indirect bilirubin,cardiopulmonary bypass time,duration of ICU & mechanical ventilation ,Max.DOAB,preoperative pulmonary hypertension and backward heart failure.The six patients in group B showed good correlation between the decreasing point of s-bilirubin and the starting day of oral or tube feeding.

• Korean Journal of Adult Nursing
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• v.18 no.5
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• pp.790-797
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• 2006

Purpose: The purpose of this study was to investigate bone density and risk factors related to osteopenia to unmarried young adult women. Methods: The subjects consisted of 125 female college students. SPSS 12.0 program was used for the data analysis with t-test, ${\chi}^2-test$. The BMD of the calcaneus and body mass index (BMI) were measured with peripheral dual energy X-ray absorptionmetry. Other physical characteristics were measured with a scale and questionnaires. Results: The general characteristics of these people showed that the average age was 22.1 years old and that the average BMI was 20.8. The mean of BMD was normal, but 24.8% were osteopenia, 75.2% were normal. In the normal and osteopenia groups, there were significant differences in the status of the BMD according to age, height, weight, BMI, regular exercise, house chores, and the experiences of being on a diet. Conclusion: Women in their twenties had some osteoporosis risk, but they can change their BMD by doing regular exercise and by eating food to peak bone mass. For building peak bone mass, they need take exercise programs and education programs to prevent osteoporosis and follow-up care.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.97-109
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• 2004

The disposal of stormwater is one of the major problems in urban water management. One method of reducing peak runoff rates and other detrimental impacts of stormwater is detention storage. Detention ponds as a water quality control alternatives have been investigated by a number of researchers. Recognizing multiple roles such as flood peak attenuation, pollution removal and aesthetic enhancement, the design and management of detentions ponds deserve more research. The purpose of this research is to establish design criteria wet detention ponds to improve water quality. Water quality in detention pond discharge might be improve with physical, chemical and biological alterations. Physical alteration was focused in this study. There are several methods for estimating the suspended solid control capability of wet detention ponds. Existing models of suspended solids removal are based on sedimentation and gravity settling theory. The pollutant trap efficiency of pond is a function of several interrelating factors. Detention time is the most important factor, because it determine gravity settling quantities of pollutants. Desirable modification of physical factors for improvement of water quality in wet detention ponds are volume ratio, area ratio, length to width ratio, depth, out let location, bottom soil type. In order to apply design procedure in actual site, Namak new town development area was selected.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.49-50
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• 2021

However, in the case of concrete, there is a concern that carbonation may proceed due to environmental factors. However, in the case of concrete, there is a concern that carbonation may proceed due to environmental factors. Research is steadily underway to prevent carbonation because carbonation decreases durability and increases the risk from disasters. However, there are many cases in which studies related to carbonation have been conducted only with materials in the same space. Therefore, in this study, FT-IR was used to analyze the difference in carbonation components by structural parts of old buildings. As a result, it was confirmed that there was a difference in peak values for each structural part of the building. The difference in peak values was determined to indicate differences in components, so the level of carbonation progress was different, and it is believed that differentiated repair and reinforcement methods will be needed depending on the structure.

• Korean Journal of Health Education and Promotion
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• v.6 no.1
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• pp.75-90
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• 1989

This study tries to show the physical growth patterns and various adolescent characteristics by using longitudinal data for the height, weight, chest girth and sitting height of 1, 132 high school students in Seoul. And this study also tries to show what influencing factors on the physical growth of this aged population. The followings are the results. 1. The boys have their peak velocity of height when they are 12~13 years old. And the girls have when they are 10~11 years old. Peak velocity of weight for boys is at the age of 13~14. And for girls is at the age ofr11~12. Peak velocity of chest girth for boys is at the age of 12~13. And for girls is at the age of 11~12. Peak velocity of sitting height for boys is at the age of 13~14. And for girls is at the age of 11~13. So girls of this period grow more rapidly by around two years than boys. 2. The menarche of girls begins at the age of 12.4. So it begins 1.4 year before peak height velocity period. 3. Of life behavior boys contingency coefficient between essential time and height and weight is .5150 and .479 5, that between studying time and height and weight is .3344 and and .2912(In case of girls is .4735, .4321, .3247, .3134).