• Journal of the Korean GEO-environmental Society
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• v.21 no.8
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• pp.15-27
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• 2020

In the current paper, a series of advanced 3D finite element analyses have been performed on existing pieces of work of negative skin friction from a geotechnical centrifuge test and full-scale field measurements. From these analyses, key features of pile behaviour under the influence of negative skin friction which, previously, were not fully understood in existing studies, have been meticulously discussed. As such, it has been possible to successfully address several numerical modelling issues such as negative skin friction induced pile settlements and group effects (the shielding effect), the effect of sacrificial piles in groups and the interaction between the pile head and the cap, the effect of interface elements at the pile-soil interface and the time-dependent pile behaviour. During a geotechnical centrifuge test, substantial amounts of negative skin frictions were mobilised when centrifugal acceleration increased from 1g to a certain g-level due to an increase in the self-weight of soil. The behaviour of piles inside a group were heavily affected by the sacrificial piles and the connectivity between the pile head and the pile cap. In particular, as negative skin friction has time dependent qualities associated with consolidation, it was logical to perform coupled analyses when analysing piles in consolidating grounds. From the current work, several insufficiencies of previous researches have been addressed, and the engineering pile behaviour subjected to negative skin friction has been clarified.

• Journal of the Korean Geographical Society
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• v.38 no.3
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• pp.389-399
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• 2003

CRN (Cosmogenic radionuclide) methodology has been a versatile tool applicable to a wide range of geomorphology. This study was underiaken to ascertain the rate of erosion and exposure age of mountain-top detritus (tors and block streams) on Mt. Maneo by employing the concentrations of in-situ produced cosmogenic $^{10}$ Be and $^{26}$ Al from bedrock surfaces that are exposed to cosmic rays. The results suggest that tors on the summit were positioned here during the glacial period but no later than 65ka and block streams have been stabilized also since the last glacial period but no later than 38ka. The tors on the summit have been eroded at a slower rate (9m/Ma) than blocks on the hillslope (15m/Ma) since the initial abrupt exposure of each landform to cosmic rays, suggesting that there is a slight difference in the rate of erosion between the summit and the hillslope, and that the local relief between the two areas has been increased. When the $^{26}$ Al/$^{10}$ Be-$^{10}$ Be concentrations from samples are plotted in Lal's steady-state erosion island, one sample (from a for) has complex exposure histories, which can be explained by the occurrence of multiple chipping event of 5cm to 60cm in length on the surface of the rock.

• Korean Journal of Oriental Medicine
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• v.5 no.1
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• pp.81-100
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• 1999

The result from the research on the disease classifications of the traditional medicine in China, Japan, Taiwan, and North Korea are followings: 1. It is remarkable that China has two different classifications. One is of the diseases named by western medicine and the other is of the syndromes compounded with parts, characters, and pathology of the diseases. The Traditional Chinese Medicine has 615 codes for diseases in 7 departments, and 1684 codes for syndromes. It seems that they have tried to match each disease named by the traditional chinese medicine to each one named by western medicine. But, they have left the diseases impossible to be equivalent to the ones in western medicine themselves and used the same codes of western medicine when the diseases are the same ones in western medicine. 2. In Taiwan, they try to connect the diseases named by the traditional medicine to the ones named by western medicine based on ICD-9. But, they did not attempt to classify the diseases of the traditional medicine by its own ways. The names of diseases in Taiwan medicine include both diseases and syndromes. It is limited to name syndromes by the traditional medicine. And, Taiwan medicine follows ICD in naming injuries. 3. Japan has not got the disease classification for the causes of death, but only the Japanese disease classification for the causes of death, a translation 'The international disease classification for the causes of death. Therefore, The diseases named by traditional medicines are excluded in the public medicine by some Japanese medicines which diagnose through the western medicine and treat by Wa Kang medicine. 4. I can't find out the data over the disease classification for the causes of death by traditional medicine in North Korea. Instead, I can refer to case histories in which differentiation of symptoms and signs and points about them by traditional medicine and the final diagnoses and report about examination by the western medicine has been recorded. In conclusion, It is a distinctive feature that they connect the diseases and the syndromes by the traditional medicine to the ones by the western medicine, and don't tell the diseases from the syndromes.

• Journal of Nutrition and Health
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• v.31 no.1
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• pp.96-101
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• 1998

The prevalence of iron deficiency in later infancy and the toddler years(25% to 40% at 1 year of age) has not decreased remarkably , except in Western countries. The purpose of this study was to 1) determine the relationship between current feeding practices and iron status, and 2) assess compliance to infant feeding instructions. Two groupsof infants were examined. The first group of 302 infants aged 6 to 24months was seen at a well baby clinic while the second group of 135 infants of the same age group was assessed by venipuncture. Cutoff values for laboratory tests were as follows ; hemoglobin<11g/dL, mean corpuscular volume (MCV) <72fl ; red cell distribution width(RDW)>15% ; serum ferritin level<10ng/ml ; and transferrin saturation (serum iron(TIBC)<10%. The diagnosis of iron deficiency anemia (IDA) was made when a low hemoglobin level was associated with either low ferritin orlow transferrin saturation . Of the 302 children brought to the well baby clinic , 12.3%(n=37) were found to have anemia (hemoglobin<11.0/dL). In terms of children grouped according to feeding practices, it was found that children with anemial comprised 32.0% (24/75) of the prolonged breast-fed group (Group A), significantly more than the 4.0%(7/176) of the artificial milk feeding group(Group B). and 3.9%(2/51) of the switched from breast milk to iron -fortified weaning foods group(Group C).Among the 107 children with IDA , iron deficiency in 105 children(98.1%) was suggested by their dietary histories ; exclusive or prolonged breast-feeding for more than 6 months without iron fortification in 98 infants ; cow's milk consumption> 500ml/day without iron fortification during infancy(n=12), or >800ml without iron-fortified foods after infancy(n=15) ; and the use of unfortified forumula or unbalanced diets, mainly limited to rice gruel. Despite the relatively high (79.6%) motivation on the part of the infants mothers and supervison by professional personnel, the poor results in the infants receiving iron fortified foods were due to poor compliance(85.75). Among the mothers of 98 IDA patients who were contacted by telephone , it was revealed that 29% did not give the oral iron preparation for more than 2 months. Furthermore, negligence or disregard by the parents occurred in 14% of the case , discontinuance of the oral iron preparation by the parents due to side effects occurred in 6%, and the children's refusal or poor oral intake and no further trial occurred in 6%. The dietary history of a large group of infants was highly predictive of their risk for anemia . Continued consumption of breast milk until the age of 1 year is not warranted unless iron-fortified foods are given concomitantly. Because there is a problem with compliance, more successful and safe strategies for preventing iron deficiency woold included dual coverage in the from of therapeutic iron supplementation as well use of iron-fortified foods for teddlers who are at risk of iron deficiency.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.719-733
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• 2000

Normally, a digital geologic map can be defined as mappable one whose spatial information with geographic information details and geologic database attribute, recorded in a digital format that is readable by computer. It shows fundamentally two different conceptual perspectives: cartography for digital mapping and analysis for geo-data processing. While, as both aspects basically relate to natural entities and their interpretation of complex features fused with multi-sources, digital geo-data mapping or geologic mapping, it should be distinguished from digital mapping in engineering such as UIS(Urban Infomation System) and AM/FM(Automated Mapping/Facilities Management). Furthermore, according to short-cycled development of GIS(Geographic Information System) software architecture based on IT(Information Technology) and wide expansion of GIS applications' fields, the importance of domain analysis and application model is emphasized at digital geologic informatizaion. In this paper, first terms and concepts of geo-data model with general data modeling aspects are addressed, and then case histories for geo-data modeling and several approaches for data modeling in GIS application fields are discussed. Lastly, tentative conceptual geo-data modeling by using UML(Unified Modeling Language) of OO(Object-oriented) concepts with respect to USGS/AASG geo-data mode is attempted. Through this approach, the main benefits for standardization and implementation lineage with conceptual model in consideration to reusability are expected. Conclusively, it is expected that geo-information system and its architecture by UML is the new coming key approach for the GIS application in geo-sciences.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5C
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• pp.185-192
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• 2012

The objective of this study is to present and verify a method for evaluating the fundamental period of a rockfill dam using artificially generated vibration from a blasting event. In this study, the artificial blasting vibration tests were carried out at the site adjacent to the existing Seongdeok Dam for the first time in Korea. The artificial vibrations were induced by 4 different types of blasting with the various depths of blasting boreholes and the various explosive charge weight. During the tests, the accelerations time histories were recorded at the crest of the dam. In this acceleration history, only free vibration decay part following the main vibration event was extracted and it was analyzed by frequency domain analysis using Fast Fourier Transform (FFT). From the results of FFT, the fundamental period of the target dam was evaluated. It is found that the effect of different blasting types on the fundamental period of the target dam is negligible and the fundamental period of the target dam can be consistently obtained by blasting vibration tests. Furthermore, it is found that the period of the target dam calculated by the method using blasting vibration test is similar to that obtained by the method of previous researchers using the real earthquake records. Therefore, in case that the earthquake record is not available, the fundamental period of a rockfill dam can be reasonably evaluated if blasting vibration test is allowed at the site adjacent to the dam.

• Journal of Preventive Medicine and Public Health
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• v.14 no.1
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• pp.43-51
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• 1981

The objective of the study is to measure the changes in measles infection and measles vaccination rates for the past 10 years in a rural area, Kang Wha. The study population were the entire children who were born between 1971 and 1950 in three townships (Sunwon, Naegae, Buleun) in Kangwha County. Two interview surveys were carried out during the 10 years of period, one in 1977 and the other in 1981. The data were collected by Family Health Workers through interview with structured questionnaires. The diagnosis of measles was mainly based on histories, symptoms and sighs of the disease. If a mother had reported measles history of her child, a public physician reviewed and decided the final diagnosis of the reported case. A retrospective cohort observation was done in order to see the trends of measles infections and measles vaccinations. The major findings were as follows; 1. The 5 year prevalence rate of measles vaccinations was 51.3% between 1971 and 1975 and 71.9% between 1976 and 1980 respectively. The difference between two periods was statistically significant (P<0.05). The secular trend of measles vaccinations showed increasing tendency from 1971 to 1978 and since then kept maintained. 2. In the birth cohort analysis of measles vaccinations, the vaccination rates, in general, were higher in the later cohort groups than that of earlier cohort groups. 9. The 5-year experience rates for measles infections were 24.3% between 1971 and 1975 and 17.2% between 1976 and 1980 respectively. This difference was statistically significant(P<0.05). The secular trend of experience rates for measles infections showed decreasing tendency from 1971 to 1980 except an outbreak in 1976. 4. The birth cohort analysis of experience rates for measles infections showed that the rate was higher in the later cohort groups than that of the earlier cohort groups. This decreasing tendency was prominent between $1973{\sim}1974$ and $1976{\sim}1977$. 5. The distribution of age specific incidence rates for measles infections showed unimodal curve with the peak at the age of 12 to 18 months. This findings were same in both two surveys. 6. Seasonal variations of the measles infections showed two peaks, one major peak in March through May and the another minor peak in September through December. 7. The 5-year reduction rate for measles infections among those vaccinated was 90.4% between 1971 and 1975 and 88% between 1976 and 1980.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.251-257
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• 1984

Low birth weight baby, defined as the baby born with less than or equal to 2,500g of body weight by WHO has been a great concern in the fold of maternal and child health since the low birth weight is a major cause of high perinatal mortality. Any measure to prevent the low birth weight baby is most desirable not only for saving the life of a baby but also for levelling up the health of the whole society. The authors attempted to figure out how some known maternal risk factors are related to the low birth weight and to measure their strengh of associations in terms of relative risk using hospital birth records. For this study, hospital birth records of 66 low birth weight cases and sex-parity matched 198 normal controls were chosen from Kangnam St. Mary's Hospital, Catholic Medical Center, and the data were analyzed in regards to several maternal factors. The risk factors studied were mother's age, mother's ABO blood type, previous histories of abortion, low birth weight baby, fetal wastage, and maternal diseases represented by anemia, hypertension, proteinuria, and glucosuria. The results obtained in this study were as follows: 1. The mean body weight of the cases and controls were 1,955g and 3,251g, respectively, and the heights were 41cm for cases and 50cm for controls. Mean gestation periods of cases and controls were 34 weeks and 39 weeks, respectively. 2. Young mother(less than or equal to 20 years of age) or old mother(more than or equal to 30 years of age) experienced more frequently the delivery of low birth weight babies than mothers in between 21 and 29 years of age. But the difference was not statistically significant. 3. Mothers whose blood type was O tended to have slighty higher frequency of low birth weight babies while B mothers have lower frequency. But the difference was not statistically significant too. 4. Those mothers who had experienced low birth weight baby in the past tended to give more births of low birth weight babies. This factor is even statistically significant and the relative risk of the prior experience of low birth weight was 6.7. 5. Mothers with experience of fetal losses and mothers of more than two pregnancies had higher frequency of low birth weight than the mothers with no fatal losses and of first pregnancy, but the difference was not statistically significant. 6. Statistically significant higher frequency of low birth weight were found in mothers with hypertension(odds ratio=4.07), anemia(odds ratio=22,33), and proteinuria(odds ratio=2.79). In summary, these study results strongly suggest that in order to prevent the low birth weight, special care should be made when the mother is too young or too old, and when the mother has experienced deliveries of low birth weight and fetal deaths. Medical control for the maternal diseases such as anemia and hypertension is also needed before or during the pregnency.

• Journal of the Korean Geosynthetics Society
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• v.4 no.3
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• pp.35-43
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• 2005

The geosynthetic reinforced segmental retaining walls(SRW) are improved that the disadvantage of existed retaining wall and the workability in field. Recently, the segmental retaining wall is replacing the exited wall because it is quickly advanced to using by the block in-situ. The use, therefore, is increasing. But, the trends of the large scaled construction was developed that the problems likely to crack and collapse, those are caused of careless in design and construction of SRW not considering about various surrounding conditions. In this study, the cause analysis on destructed SRW was carried out that based on the datum of measured displacement of walls, rainfall features and ground sounding conditions. Also, the analysis of the global slope stability was carried out on collapsed section and non-collapsed section using critical equilibrium method. For the rational stability and analysis of slope including SRW structure, the site conditions including situations of topography, ground and histories of construction and collapse etc should be considered. The rational countermeasure methods for non-collapsed and collapsed areas may be sustained as much as possible current state.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.2
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• pp.155-170
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• 2020

In this paper, a risk management system applicable to NATM tunneling projects is proposed. After investigating case histories in NATM tunnel collapse, this paper analyzes the potential risk factors and their corresponding risk events during NATM tunnel construction. The risk factors are categorized into three groups: geological, design and construction risk factors. The risk events are also categorized into four types: excessive deformation, excessive deformation with subsidence, collapse inside tunnels, and collapse inside tunnels with subsidence. The paper identifies risk scenarios in consideration of the risk factors and proposes a risk analysis/evaluation method for the NATM tunnel risk scenarios. Based on the evaluation results, the optimal mitigation measure to handle the risk events is suggested. In order to effectively facilitate a series of risk management processes, it is necessary to develop a risk register and a management ledger for risk mitigation measures that are customized to NATM tunnels. Lastly, the risk management for an actual NATM tunnel construction site is performed to verify the validity of the proposed system.