• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.17-24
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• 2003

One of the reasons for brittle failure in reinforced concrete structures subjected to severe earthquake is due to large local bond-slippage of bars resulting in fast bond degradation between reinforcing bars and concrete. This study aims to evaluate effects of bar deformation height on bond performance, specially, bond degradation under cyclic loading. Bond test specimens were constructed with machined bars with high relative rib areas. The degree of confinement by transverse bars is also another key parameters in this bond test. From test results, amounts of energy dissipation are calculated and compared for each parameter. Test results show that bond strength and stiffness drops significantly as cycles increases. The confinement and high relative rib area are effective to delay bond degradation, as the reduction of bond strength of cyclic loading compared to monotonic loading decreased for bars with large confinement and high relative rib areas. The energy dissipation also increases as the degree of confinement and relative rib area increases. However, tested bars with very high rib areas show that the bond may be damaged at relatively small slip because of high stiffness. The study will help to understand the bond degradation mechanism due to bar deformation height under cyclic loading and be useful to develop new deformed bars with high relative rib areas.

• Journal of Sasang Constitutional Medicine
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• v.2 no.1
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• pp.71-85
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• 1990

673 third-year students of boy's and girl's high schools in Taegu city and Kuni-gun and Youngyang-gun and Euisung-gun in Kyongbuk province were selected and investigated as the subject, of this study on the correlation between Lee Jae Ma's Four Types of Essential Physical Constitution and Physical Form index. The result of the study was found as follows. First, as for Height, the findings were not identical with the expression that "person of shaoyin(minor Yin) Type are short and small -- while person of Taiyin (major Yin) Type are tall and big," cited in classification of four different constitutions in a document named "Dong-Eu-Su-Se-Bo-Won". Comparison of persons of Shaoyang (minor Yang) - Type proved infitness due to the lack of data on Height in documents concerning Lee Jae Ma's four types of essential physical constitution. Second, as for Sitting Height, the correlation was prored between the findings of this study and the expression in the above document describing external physical characteristics of shaoyin-Type persons that "The upper part and' the lower part of the body are well balanced", but in point of Relative Sitting Height, none between the two. Third, as for Chest-Girth and Relative Chest-Girth plus Weight and Relative Weight, the expression that "Persons of Taiyin(major Yin) Type have the largest physique of the lour types of persons in the characteristics of external physical features, and that they also tend to have continental(widechest or large-scaled) character and strong nerve, that they are stoutly-built and fal." proved to have the correlation with the findings of this study. Fourth, in point of Chest-Girth and Relative Chest-Girth, this study found that its findings have the correlation with the phrase that "Chests are well developed upwar -- and sturdy and solid." in describing the characteristics of Shaoyang (minor Yang)-Type person' external physical features, and that with the phrase that "Chests are narrow" in the case of Shaoyin(minor Yin)-Type persons. Fifth, as for Weight and Relative Weight, the correlation was found between the findings and the expression that "shaoyin-Type persons have comparatively less flesh" as a sign of external physical characteristics of Shaoyin-Type persons. The above-cited findings proved that there exist some correlations between external physique of the Lee Jae Ma's four types of essential constitution and physical Form Indexes. Actually, however, in clinical classification, it is desirable that this approach should be consulted only after carefull consideration based on Lee Jae Ma's theory, and it seems imperative to continue the study of objectivization of Lee's theory.

• Journal of the Korean Dietetic Association
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• v.2 no.1
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• pp.29-37
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• 1996

This study was undertaken to evaluate the relation between obesity and dietary life of children aged 4-7 divided into two groups based on height for age, weight for age and weight for height. Controls were selected based on sex and age similar with those of cases. Cases and controls were selected using the combination of weight for height, weight for age and height for age by the World Health Organization standard. Cases were 23 children judged as obese. Controls were 37 judged as normal. Whether their mother had a job or not, showed relative risk 1.35(95% C1 0.32-5.64). In obese group, employmental statue of mother was 17.4% compared with 13.5% in control group. In mother's concern for cooking pattern, the relative risk was 5.64 and 95% CI was 1.70-18.66 in the item of "We consider the color arrangement when we serve foods" which was the highest rate. The item having the lowest relative risk was "We cook the meal by ourselves with spending time" which of the relative risk was 0.52 and 95% CI was 0.16-1.65. The item having a great significance in the dietary habit of subjects were "They beat the tablewear with the chopstick"(RR:1.64, 95% CI:0.22-12.73) and "I talk with food in my mouth"(RR :1.11, 95% CI:0.39-3.15), and the other items didn't show significancy. Number of food eating per day for male was 30.0$\pm$10.93 in obese group where as 23.2$\pm$9.80 in control group. 22.3$\pm$4.56, 21.8$\pm$10.91 were taken obese group and control group respectively in female. In the survey for general habit in life, the item of "We has a time for conversation with our family regularly" was high correlation to obesity and item of "We made our children change clothes and go to toilet themselvesj has slight relation to obesity. From above, we observed normal and obese children had different factors such as mother's attitude for preparing meals, table manners and habit of living. So we should take a continuous interest in children's dietary life in order to correct the wrong dietary habit and to protect from future problems.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.3-8
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• 2004

This study describes the validation of the GPS/Levelling using GPS data that were obtained from three Permanent GPS stations of the Jeju island. Each orthometric height of three Permanent GPS stations was calculated from the Bench mark of levelling with Traverse-survey and relative baseline processing The test result shows that the error of closure of orthometric height was about 1.6cm and one of ellipsoidal height was about 1.5cm. This result represents that the geoidal height and undulations are regular in the Jeju island. According to the test results, it is identified that one can calculate the orthometric height using Permanent GPS station data rather than traditional levelling method which has a some complexity especially in Jeju island.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.3
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• pp.128-133
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• 1990

An equation is presented to calculate wave height due to shoaling, refraction and bottom friction. The equation in an integral form is evaluated by two different methods： A numerical method and an analytical method based on approximation. Both methods are used to calculate wave height and show very good agreement between their results. As shown in the figure of wave height variation vs. relative water depth, an increase of incident angle leads to a decrease in wave height. For the case of normal incident wave, the present equation can be reduced, under some assumptions, to the existing equation of Bretschneider and Reid (1954).

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.145-172
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• 1984

In order to assess the physical growth pattern of Korean Youth, the authors measured the body height, body weight, chestgirth and sitting height of 40967 persons (24832 males and 16135 females) from primary schools, middle and high schools and colleges of metropolitan (urban) and rural areas, and calculated the mene, standard deviation, standard error and coefficient variance of the body weight chestgirth, sitting height and various pertinent index by body height to demonstrate the standard physical growth and development by body height of sex and age. The following conclusions were obtained. 1. Physical growth and development: Rapid growth of physical growth in terms of body height has been observed among males in the age $7{\sim}15$ and among female $7{\sim}13$. Growth in terms of body height turned out to be slower among students of higher age by both sexes. The age of cross over between to sexes is between 10 to 13 years where upon girls out grows boys. Maximum annual growth were upon girls out grows boys. Maximum annual growth were both of 6.16cm from 8 to 9 years old and 12 to 13 years old for boys and 7.2cm from 8 to 9 and 6.1cm from 9 to 10 for girls. This indicates that girls enter a rapidly growing stage 2 years earlier than boys. Meanwhile, prominent improvement in body height of national students over period of ten year was noticed. 2. The distribution status of body height by age: The distribution status of body height by age were as follows; 7 year of age: boys-30cm range of body height from 104.0cm to 133.9cm, girls-27cm from 104.0cm to 130.9cm 8 year of age: boys-30cm from 116.0 to 145.9cm girls-33cm from 113.0 to 145.9cm 9 year of age: boys-30cm from 116.0 to 145.9cm girls-33cm from 113.0 to 145.9cm 10 year of age: boys-39cm from 116.0 to 154.9cm girls-39cm from 119.0 to 157.9cm 11 year of age: boys-45cm from 119.0 to 163.9cm girls-39cm from 122.0 to 160.9cm 12 year of age: boys-45cm from 125.0 to 169.9cm girls-42cm from 125.0 to 166.9cm 13 year of age: boys-45cm from 128.0 to 172.9cm girls-42cm from 128.0 to 169.9cm 14 year of age: boys-48cm from 131.0 to 178.9cm girls-36cm from 134.0 to 169.9cm 15 year of age: boys-42cm from 137.0 to 181.9cm girls-33cm from 137.0 to 169.9cm 16 year of age: boys-39cm from 146.0 to 184.9cm girls-30cm from 143.0 to 172.9cm 17 year of age: boys-39cm from 146.0 to 184.9cm girls-27cm from 143.0 to 169.9cm 18 year of age: boys-36cm from 152.0 to 187.9cm girls-27cm from 146.0 to 172.9cm 19 year of age: boys-30cm from 155.0 to 184.9cm girls-24cm from 146.0 to 169.9cm 20 year of age: boys-24cm from 158.0 to 181.9cm girls-l8cm from 149.0 to 166.9cm 3. Standard values of body weight, chest-girth and sitting height by body height of age were found all age groups from 7 to 20 years old and listed in tables from3-a to 16-a. 4. Standard values of relative body weight, relative chestgirth and relative sitting height by body height of age were found all age groups from 7 to 20 years old and listed in tables from 3-b to 16-b. 5. Standard values of physical and nutritional indices (Rohrer index, Kaup index, Vervaeck index and Pelidisi index) by body height of age were found all age groups from 7 to 20 years old and listed in tables from 3-c to 16-c.

• Structural Engineering and Mechanics
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• v.74 no.4
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• pp.533-545
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• 2020

An optimal design method for a spoke double-layer cable-net structure (SDLC) is proposed in this study. Simplified calculation models of the SDLC are put forward to reveal the static responses under vertical loads and wind loads. Next, based on an energy principle, the relationship among the initial prestress level, cross-sectional areas of the components, rise height, sag height, overall displacement, and relative deformation is proposed. Moreover, a calculation model of the Foshan Center SDLC is built and optimized. Given the limited loading cases, material properties of the components, and variation ranges of the rise height and sag height, the self-weight and initial prestress level of the entire structure can be obtained. Because the self-weight of the cables decreases with increasing of the rise height and sag height, while the self-weight of the inner strut increases, the total weight of the entire structure successively exhibits a sharp reduction, a gradual decrease, a slow increase, and a sharp increase during the optimization process. For the simplified model, the optimal design corresponds to the combination of rise height and sag height that results in an appropriate prestress level of the entire structure with the minimum total weight.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2414-2419
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• 2007

A rectangular fin with variable fin height, fin length and surrounding temperature is analyzed using a one-dimensional analytical method. Both the heat loss from a rectangular fin with non-insulated fin tip and that with insulated fin tip are presented as a function of the fin height, fin tip length and the convection characteristic number. The relative error in the heat loss of these two cases is also given as a function of the same variables. One of the results shows that the trend of heat loss for both cases with the variation of given variables is similar even though the relative error increases as the shape of the fin becomes shorter and fatter.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1177-1181
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• 2009

Heat loss from a convective rectangular profile annular fin with variable inside fluid heat transfer coefficient and fin height is calculated by using both the one dimensional analytic method and two dimensional variables separation method. Heat loss from the two dimensional method and the relative error of heat loss between the one dimensional method and two dimensional method are presented as a function of the fin length, ambient convection characteristic number and fin height. One of the results shows that the relative error of heat loss between one dimensional method and two dimensional method is within 0.7% in the range of given parameters in this study.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.45-51
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• 2005

The solar shading height for the cultivation of plants is a very important factor because it has an effect on the variations of the solar energy. In this study, the solar shadings were built in Daegu region to investigate the optimum thermal conditions for the cultivation of plants and to provide the basic data. The thermal environment factors (dry bulb temperature, relative humidity, air velocity) were then measured and analyzed. It is found that the heights of the solar shadings have an uniform effect on the thermal environment for the cultivation of plants: the higher the heights of the solar shadings the higher temperature was obtained. But surprisingly this trend was not found for the relative humidity and the air velocity.