• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2000.09a
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• pp.201-210
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• 2000

Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mats. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributons. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks dial not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the $K_{I}$ vague increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.s.

• Tunnel and Underground Space
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• v.10 no.3
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• pp.447-456
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• 2000

Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mass. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributions. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks did not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the K$_1$ value increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.74-86
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• 2000

Objectives : This is the experimental paper to study the curative and preventive effects of Dansambohyultang, Methods : Oriental herb medicine for gastro-intestinal disease caused by stress, on the rats put under the stress through starvation, heating and immoblization, the author used four different group; the normal group, which was not put under stress and well fed, and the control group, to which the drug was not administered and put under the stress through starvation, heating and immoblization, the Sample I, to which the drug was administered before they were put under stress, the Sample lI, to which the drug was administered after they were put under stress. Results : When a Masson's trichrome stain method was applied to the control group, a small size of ulcer was found in the fundus and the pylorus, and atrophy was observed in the neck region of mucous membrane. When the drug was administered to the Sample I and the Sample II, the former recovered from the ulcer and atrophy to almost normal and showed better results than the latter. When a Masson's trichrome stain method was applied to the control group, atrophy of mucous membrane was found all over the intestines. When the drug was administered to the Sample I and the Sample ll, the curative and recovered effects was seen in both, but the former showed better results than the latter. After application of Mayer's hematoxylin stain method, the observation of numerical changes of goblet cells in the small intestines showed the most significant decrease in the control group. In the Sample I, the number of the cells in the duodenum, the jejunum and the ileum returned to an almost normal level. In the Sample II, a slight increase was observed only in the ileum. After application of Mayer's hematoxylin stain method, the observation of numerical changes of goblet cell in the large intestines showed a significant decreased in the control group. Both the Sample I and the Sample II showed an increase in the number of goblet cells in comparison with the control group. When a serotonin-immunoreaction test was applied, the control group showed a general decrease in the number of gastro-entero-endocrine cells, The Sample I showed the effect in all over gastro.intestinal tract as compared with control group and the Sample II showed the effect in all over gastro-intestinal tract except the duodenum and the former showed better results than the latter. Conclusion : According to the above results, the regions which are most sensitive to stress were observed to the ileum and the colon. It was concluded that Dansambohyultang has a remedical value particularly on the abnormalities caused by stress in all over gastro-intestinal tract and it was found to be more effective in the Sample I than in the Sample ll. Judging from the fact that the Sample I showed better results than the Sample ll, Dansambohyultang can be said to have a preventive effect more than a curative effect on gastro-intestinal tract disease.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.137-144
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• 1986

The author has studied the $\beta$-glucuronidase activity in several tissues such as liver, stomach and small intestine of the male and female rabbits infected with different doses of metacercariae of Clonorchis sinensis. The metacercariae of Clonorchis sinensis were isolated from Pseudorasbora parva caught in Kim Hae by digestion technic. The experimental animals were sacrificed in the period of 1, 7, 14, 21, 28 and 35th days following the infection. The results obtained were summarized as follows. 1. In the groups infected with 100 metacercariae, $\beta$-glucuronidase activity was slightly increased during the entire periods than control rabbits. It was the highest in the first day with 1.535 and $1.421m{\mu}/g$, 14th days with 2.521 and $2.200m{\mu}/g$, and then lowered by the time, gradually. 2. In the groups infected with 500 metacercariae, $\beta$-glucuronidase activity was highly increased on the first day with 1.535 and $1.856m{\mu}/g$ than that 100 metacercariae groups according to each organs. It was the highest on the 7th day and 14th day. 3. In the groups infected with 1,000 metacercariae, $\beta$-glucuronidase activity was remarkably increased in the first and 14th days according to each organs, and then lowered gradually day by day. 4. $\beta$-glucuronidase activity of all organs was more increased than that of normal organs and the highest activity in the liver with $2.521m{\mu}/g$, intestine(1.612) and stomach (1.581) respectively. 5. $\beta$-glucuronidase activity of rabbits was higher in the female than in the male. On the basis of these results, it was suggested that $\beta$-glucuronidase activity was affected by the duration of infection and by the number of Clonorchis sinensis, according to the organs and sex of the rabbits.

• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.166-175
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• 1977

The author have performed an epidemiological study on the accidental deaths at industry from 1970 to 1975, in order to seek for the preventive measures of industrial accident with the under-standing of its cause and characteristics of the accidental deaths. The obtained results were as follows; 1. Total number of deaths for 6 years were 361 (350 males, 11 females). and the mean death rate was 33.8 per 100,000 industrial workers during 6 years. By the highest as 52.9 was in 1974 and the lowest as 13.7 in 1970. By the industry group, the death rate of Electricity, Gas and Water was 149.3, Construction 83.9 and the lowest was Manufacturing as 18.3. 2. Standardized mortality rate of the cases by the age group showed that 20-29 years old group was 43.0, 40-49 years old group 38.1, 30-39 years old group 32.0, and the lowest as 17.9 was under 19 years old group. 3. The cumulative percentage of the cases by years of service showed that under 6 months was 60.4%, under 1 year 72.9%, under 2 years 83.1%. 4. By the month of occurrence, the highest was 15.8% which occurred in August and the lowest was 5.8% in February. The highest as 19.1% was on Friday and the lowest as 11.9% on Monday by the day of a week. 5. By the causes of accident, car accidents was 28.3%, fall accidents 19.1%, accidents by a crash 9.1% in that order. By the location of injury, head was 44.6%, multiple injuries 33.0%, chest 10.5%, and back was the lowest as 1.9%. The distribution of the cases by nature of injury shelved that cerebral contusion and hemorrhage was 39.4%, fracture and dislocation 33.2%, asphyxia 8.0% in that order. 6. The cumulative percentage of the cases by the duration from injury to death showed that the injuried day was 74.2%, within 3 days after injury 88.5%, within 7 days 96.1%. Therefore most of the cases were occurred within 7 days after injury. 7. Byythe daily mean wages, most of the cases as 91.7% were under 2,000 won, and more 4,000 won was 1.6% merely.

• Journal of Preventive Medicine and Public Health
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• v.20 no.2 s.22
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• pp.331-340
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• 1987

To determine the incidence rate of school accidents and its associated factors, a cohort observation was carried out in a boys' high school of a total of 2,324 students for an academic year from March 1986 to February 1987. Data for accidents were collected by the author (school nurse) as students came to the school health station for treatment of accidental injury. Data for school activities were obtained from the diary of academic affairs. A total of 603 students made 1,126 visits to the station for accidental injury during the study period that gave an average 1.9 accidents per student. The average number of visits for accidental injury per day was 5.1 and the incidence rate of accidental injury was 2.2 per 1,000 student days. Each class had about 30 accidents on the average in a year. However there were two classes that had exceptionally high incidence rate of accidents; 54 accidents in one class where 10 athletes were assigned and 58 accidents in the other class where the teacher in charge was On vacation for two months. The highest incidence rate of accident was observed in June (3.4 per 1,000 student days) and the lowest rates were in December and February (1.5 and 0.7 per 1,000 student days, respectively) and there were no appreciable difference by day of week. Accidents were caused by mischief or carelessness of students in 62.2% and by the inappropriate tools and facilities of school in 18.6% . The accidents caused by tools and facilities were mainly due to the antiquated chairs and tables. Referral rate to hospital for severe injury was three times higher in cloudy days and five times higher in rainy days than in clear days. There was almost no accident during the examination period but increased after the examination. Based on these findings, following measures are recommended to prevent school accident: disperse the athletes throughout the classes: should the teacher in charge leave the class for a long period, replace with another teacher who is familiar with the class to keep order; replace or repair the inappropriate tools and facilities; and warn the students for the risk of accident or broadcast music or let the students have light physical exercise to relieve the tension in cloudy or rainy day and after examination.

• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.125-133
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• 1977

The author have performed, from June to July 1976, a sociomedical study on the 314 prostitutes which was engaged in tourism in Dongrae, Busan. The obtained results were as follows: 1. Age distribution was from 20 years old to 34 years old and the highest as 36.6% was 23-25 years old group. Most of the respondents as 95.2% were under 31 years old group. 2. Distribution of respondents by educational level showed that the group below the graduated primary school was 47.2%, middle school 29.3% and high school 57.0% in that order. 5. By the occupation before be ruined, none was 34.5%, waitress at saloon 24.2%, hostess 14.3%. 4. By distribution of birth place, most of the respondents as 64.0% were Gyeongsang Do(37.9%) and Busan City (26.1%). 5. Distribution of respondents by family status showed that only mother was highest as 43.9% and 82.2% of respondents have been supported their family. 6. Monthly incomes of respondents were distributed from 50,000 Won to 250,000 Won, and 50,000-100,000 Won group was the highest as 46.2%. In monthly sundry expenses, 20,000-30,000 Won group was the highest as 27.1%. 7. Monthly supporting expenses to their family were distributed from 10,000 Won to 50,000 Won and the highest as 26.7% was 10,000-20,000 Won group. Savings per month were distributed from 10,000 Won to 60,000 Won and 50,000-60,000 Won group was the highest as 22.3%. 8. Distribution of respondents by status of luxury showed that experiences of drinking was 20.4% and smoking was 55.7%. 9. By motive of falling into the ruin, economical causes was 41.7%. Most of the respondents as 95.0% expected under 3 years in prearranged period of their occupation. 10. By number of monthly entertainment, 5-10 persons as 58.0% was the highest. 11, Distribution of respondents by status of venereal disease and pulmonary tuberculosis showed that positive of gonorrhea was 8.0%, syphilis 1.6%, and pulmonary tuberculosis was 1.6%.

• Korean Security Journal
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• no.31
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• pp.157-185
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• 2012

Today, the emergence of cyberspace and advancement of globalization caused not only the transformation of our productive and conventional life but also the revolutionary transition of use of destructive violence such as crime and warfare. This transition of environmental condition connects various security threats which separatedly existed in individual, local, national, and global levels in the past, and transformed the mechanical sum of all levels of security threats into the organic sum of multi-dimensional security threats. This article proposes that the sum of multi-dimensional security threats is caused by the interconnectivity of various different levels of security threats and the integrated interdisciplinary perspective is essential to properly understand the fundamental existence of today's security problem and the reality of fear that we face today. The holistic security, the concept proposed here, is to suggest the mode of networked response to multi-dimensional security threats. The holistic security is suggested to overcome the conventional divisional approach based on the principle of "division of labor" and bureaucratic principles, which means more concretely that national security and criminal justice are divided and intelligence, military, police, prosecution, fire-fighting, private security, and etc. are strictly separated into its own expertise and turf. Also, this article introduces integrated security approaches tried by international organization and major countries overseas with the respect of the holistic security. The author have spent some substantial experience of participant observation, meetings, seminar, conference, and expert interviews regarding the issues discussed in the article in various countries including the United States, Russia, Austria, Germany, Canada, Mexico, Israel, and Uzbekistan for the last ten years. Intelligence and information on various levels of security threats and security approaches introduced in this paper is obtained from such opportunities.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.2
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• pp.29-48
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• 2000

This study was designed to diagnose the correlations between health promotion behavior and primary school students' demographic characteristics and their self-concept, and also this study was aimed at representing the basic data of proper instruction method and school health program with the respective to primary school students' health promotion behavior through the above things. For this, author selected as 5th, 6th graders, 400 persons at 5 elementary schools located on Kyonggi province. This data utilized ANOVA, multiple regression analysis and correlation analysis by SPSS program. The findings of this study were as follows; First, there showed meaningful differences concerning their health promotion behavior according to students' demographic traits. There were a birth date, living standard, domestic environments etc. as a factors which influenced on their health promotion behavior. With this, from ex-past-facto verification for these variable factors, as their birth date was faster, living standard was higher, domestic environments was better, as their health promotion behavior was more promotive. Second, students' health promotion behavior marked 3.61 among total 5 paint with the respective to its fulfillment degree, their self-concept marked 3.45 among total 5 paint. Their mental health promotion behavior marked 3.71 with the respective to inferior category of health promotion behavior, which was the highest score. In the other hands, their physical health promotion behavior marked 3.71, social health promotion behavior marked 3.45. contrary the disease prevention, first-aid & safety, oral health, health & nutrition(P>.05). Third, there show meaningful difference, in the level of p-value <.001 with the respective to the correlations between primary school students' health promotion behavior and their self-concept, more their self-concept was positive, more their more their whole health promotion behavior(r=.479), the fulfillment degree of physical health promotion behavior(r=.384), mental health promotion behavior(r=.543), social health promotion behavior(r=.372) were high. Fourth, with the respective to the results of difference verification concerning their fulfillment degree of health promotion behavior according to the upper, middle, inferior group of self-concept, there showed statistically meaningful difference, in the level of p-value<.001. In the long run, more their self-concept was positive, more their whole health promotion behavior was high. With this, from the results of $Scheff\acute{e}$ verification, there showed meaning differences among the upper and middle group, upper and inferior group, middle and inferior group. Fifth, self-concept played the role as the most important prognostic factor with the respective to primary school students' health promotion behavior(23.0%), in the other hands, there showed positive weight of 24.0% concerning the fulfillment of whole health promotion behavior by domestic environments(1.0%). From the above results, primary school students' the fulfillment degree of health promotion behavior didn't reach to middle or inferior level. In the other hands, there showed positive effects in the correlations between self-concept and the fulfillment degree of health promotion behavior, and also high self-concept group was much positive considering inferior group in the fulfillment degree of health promotion behavior. Accordingly, more their self-concept was positive, more their fulfillment degree of health promotion behavior was effective. Eventually, in the future, there have to make an efforts to develope positive, substantial programs through their self-concept enhancement etc. in the adequate planning or operation for primary school students' health education and school health program.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.1-25
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• 1969

Since widely use of anthracite for the radiating purpose in a rearing room in Korea, the weakness of silkworm, poor uniformity of the worm growth, the increase of missing worm ratio, unusual cocoon assorting ratio, and the decrease of cocoon layer ratio have been realized by the author, therefore, he has started out to search the mechanism of these evil influences regarding with various gas densities and terms of the gas treatment which will be supposed to be a warning for temperature control during the silkworm reading work. Among the anthracite gas components, CO or SO$_2$ influence and their complexed harm effect were investigated through the use of anthracite gas, CO and SO$_2$ gas. Meantime, each treatment was applied, separately, during the worm egg stage, young instar, adult instar and whole instar, because the harm intensity for any improperable rearing condition is flexible by the growing stages. Meantime, the gas density and term variation were applied for the above each treatment such as in case of anthracite and CO gas, the following treat methods were used. 1) 0.06% for 30 mins. 2) 0.06% for 1 hour. 3) 0.1% for 1 hour. 4) 0.15% for 1 hour. on the other hand, SO$_2$ gas was used as 1) 120ppm for 30 mins. 2) 200ppm for 30 mins. 3) 400ppm for 30 mins. The measurement of gas density was proceeded by using CO tester (Carbon Monoxide Indicator) and SO$_2$ tester (Indicator Sampler Cgf) which could keep any specific density before each treatment.