• Explosives and Blasting
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• v.35 no.3
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• pp.31-54
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• 2017

In the countries operating nuclear reactors, the development of high-level radioactive waste(HLW) disposal technique is considered as an urgent and important issue for sustainable utilization of nuclear energy. In Korea, in which a low and intermediate radioactive waste repository is already operating, the construction of an underground research laboratory for in situ validation studies became a matter of interest with increasing concerns on the management of HLW. In order to construct and to operate an underground HLW repository safely in deep underground, the stability of rock mass should be guaranteed. As an important factor on rock stability, excavation damaged zone (EDZ) has been studied in many underground research laboratories in foreign countries. For accurate evaluation of the characteristics and effects of EDZ under disposal condition, it is required to use reliable investigation method based on the analysis of previous studies in similar conditions. In this study, status of foreign underground research laboratories in other countries, approaches for investigation the characteristics, size, and effect of EDZ, and major findings from the researches were surveyed and reported. This will help the accomplishment of domestic researches for developing HLW management techniques in underground research laboratory.

• Journal of Korean society of Dental Hygiene
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• v.10 no.5
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• pp.819-829
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• 2010

Objectives : The purpose of this study was to examine factors affecting the effective demand of workers for dental treatment in a bid to provide some information on the improvement of oral health. Methods : The subjects in this study were 255 workers who were engaged in the pharmaceutical industry. A self-administered survey was conducted, and the collected data were analyzed by a spss(statistical package for the social science) win 12.0 program to find out their demographic characteristics, oral health awareness, oral health behavior and factors for the choice of a dental institution. Results : 1. Concerning the level of oral health awareness, 47.0 percent were at a low level(0 to three scores), and 35.2 percent were at an intermediate level(four to six scores). 2. As to oral health behavior involving a daily mean toothbrushing frequency, they brushed their teeth 2.65 times per day on the average. The most widely utilized oral hygiene supply was mouth rinse. Regarding oral health status, 53.7 percent weren't in good dental health, and just 23.0 percent got a dental checkup on a regular basis. 45.8 percent of those who didn't get a dental checkup cited time constraints as the reason. 26.0 percent received oral health education, and 91.4 percent were aware of the necessity of a corporate incremental dental care system. 3. Marital status, age and the reliability of dental institutions made differences to their choice of a dental institution. 4. As for the relationship between oral health awareness and the factors for the choice of a dental institution, oral health awareness had a statistically significant positive correlation to the reliability of dental institutions. Conclusions : The above-mentioned findings suggest that oral health education enables workers to have a correct knowledge on oral health, to change their own oral health behavior and to make the right choice of a dental institution in consideration of their oral characteristics. They should be urged to get a regular dental checkup not to develop chronic oral diseases so that they couldn't have to receive first-aid dental treatment. To promote the oral health of workers, oral health care personnels available should be utilized, and the incremental dental care system should be more vitalized to cut down on their effective demand for dental treatment.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.387-398
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• 2008

To obtain base-line data in the low- and intermediate-level radioactive waste disposal facility, radiological environment investigation is required at least two years prior to the facility operation near the disposal facility. The investigation has been performed since January 2007 for the Wolsong LILW disposal center. In this paper, investigation procedure and detailed information obtained for six months in 2008 are described. Based on the current results, future investigation planning is also discussed for the radiological environment management of the disposal facility.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.265-282
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• 2008

Based on the site characterization works in a low and intermediate level waste(LILW) repository site, the numerical simulations for groundwater flow were carried out in order to understand the groundwater flow system of repository site. To accomplish the groundwater flow modeling in the repository site, the discrete fracture network(DFN) model was constructed using the characteristics of fracture zones and background fractures. At result, the total 10 different hydraulic conductivity(K) fields were obtained from DFN model stochastically and K distributions of constructed mesh were inputted into the 10 cases of groundwater flow simulations in FEFLOW. From the total 10 numerical simulation results, the simulated groundwater levels were strongly governed by topography and the groundwater fluxes were governed by locally existed high permeable fracture zones in repository depth. Especially, the groundwater table was predicted to have several tens meters below the groundwater table compared with the undisturbed condition around disposal silo after construction of underground facilities. After closure of disposal facilities, the groundwater level would be almost recovered within 1 year and have a tendency to keep a steady state of groundwater level in 2 year.

• Survey Research
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• v.10 no.3
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• pp.37-58
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• 2009

The purpose of this study were to identify the subgroups (i.e., latent classes) depending on early adolescents' change patterns in aggression and to test the effects of individual-background variables on determining the latent classes. For these goals, we applied Nagin's(1999) semi-parametric group-based approach to the Korean Youth Panel Study. Results showed that four latent classes were identified, which could be defined based on the patterns as low-level group, increasing group, intermediate-level group, and high-level group. By adding gender, self-control, parent attachment, teacher attachment, and the number of delinquent friends to the unconditional latent class model, we tested the effects of the variables on the latent classes. Multinomial logit analysis showed that gender, self-control, teacher attachment, and the number of delinquent friends were significant determinants of the latent classes. Findings from this study suggest the need to consider heterogeneity in the study of early adolescents' aggression to facilitate more refined targeting of intervention program.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.4
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• pp.351-357
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• 2007

The Japanese Government selected Mutsu, Aomori Prefecture as a provisional spent-fuel repository site. This comes as a result of the prefecture's five-year campaign to host the site since 2000. Korea stores spent nuclear fuel within sites of nuclear power plants, and expects the storage capacity to reach its limit by the year 2016. This compels Korea to learn the cases of Japan. Having successfully hosted Gyeongju as a site for low-to-intermediate-level nuclear waste repository, Korea has already learned the potential process of hosting spent fuel storage site. The striking difference between the two countries in the process of hosting the site is that the Korean government had to offer the local city a large amount of subsidy for hosting through competitive citizens' referendum among candidate cities while it was the leadership of the local municipality that enabled the controversial decision in Japan. It is also a distinguishable characteristics of Japan that not a huge subsidy is provided to the local host city. I hope this study offers an idea to Korea's future effort to select a spent-fuel host site.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.17-17
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• 2023

국내의 부지특성 및 감시 관련 규정은 원자력 안전위원회 고시 제2021-16호 제4조(세부지침)와 원자력 안전위원회 고시 제2021-17호 제16조에 의거하고, 국외는 국제원자력기구(IAEA: International Atomic Energy Agency)에서 안전기준을 제시하고 있다(IAEA, 2011). 따라서 국내 중·저준위 방사성폐기물 처분시설은 2006년부터 광역 지질을 포함한 부지 지질/지형, 기상, 수문, 수리지질, 인문사회 등을 망라한 조사를 시행하여 부지 현황에 대한 분석 및 안정성 평가를 수행한다. 부지감시의 수문·지구화학 분야에서는 현장 수질 측정 6항목과 실내 분석 26항목을 감시하고 있으나, 본 연구는 이 중 9개 항목(EC, Na, K, Ca, Mg, SiO₂, Cl, SO₄, HCO₃)을 선정하여 분석하였다. 연구 목적은 물시료 분석자료의 주성분-다중선형회귀-군집 분석과 Piper Diagram 분석결과로부터 해수와 담수(지하수)와의 특성분석 및 해수 영향을 분석하는 것이다. 현장 부지내 지하수 7개 관정(GM-1, 2, 4, 5, 6, 7, 8)과 해수 2개 지점(Sea-1, 2)을 대상으로 통계학적 주성분 분석결과, 대부분의 지하수는2개~4개의 요인으로 구분되고, 해수와의 유사성을 해석하기 위해 확인한 관정은 GM-5, GM-6, GM-1 지점으로 분류되었다. 상기와 같이 해수의 영향을 확인하기 위해 해수 2개 지점과 동일한 군집으로 분류되는 지하수는 GM-5 관정으로 확인되었고, 해안선에서 가까운 GM-5 관정과 같이 유사한 거리에 분포한 지하수 GM-1, 2, 4 관정은 2개 혹은 3개의 최적 군집으로 분류하였을 때도 GM-5와는 다른 특성을 보여주었다. 이는 해안과 인접하더라도 수질은 다른 지질학적 특성(지형, 기상, 단열대 등)에 따라 영향받았음을 지시한다.

• Journal of agricultural medicine and community health
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• v.8 no.1
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• pp.44-65
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• 1983

As a part of the epidemiological studies of clonorchiasis, this study was conducted to evaluate the current endemicity and the natural transition of the Clonorchis infection in Gimhae Gun and delta area a high endemic area in Korea in recent years, prior to the introduction of praziquantel which will eventually influence the status of the prevalence. The data obtained in this study in 1983 were evaluated for natural transition of the infection in comparison with those obtained 16 years ago in 1967 by the author(Kim, 1974). The areas of investigation, villages and schools surveyed, methods and techniques used in this study were the same as in 1967, except for the contents of the questionnaire for raw freshwater fish consumption by the local inhabitants. 1) The prevalence rate of clonorchiasis in the general population of the villages was 48.1% on the average out of a total of 484 persons examined. The average of those of the riverside-delta area was 65.2% and 43.0% in the inland area. Among the schoolchildren, the prevalence rate was 8.2% on the average out of a total of 1,423 examined. By area, the prevalence rate was 10.8% in the riverside delta area and 2.8% in the inland area. By sex, difference in the prevalence was seen only in the inhabitants of the inland area showing 52.4% in the male and 33.5% in the female. 2) In the natural transition of the infection, the prevalence rate among the inhabitants has decreased from 68.8% in 1967 to 48.1% in 1983, and in the schoolchildren from 56.4% in 1967 to 8.2% in 1983. The reduction rate was higher in the riverside-delta area than in the inland area. 3) In the prevalence rate by age, 11.9% was first seen in the 5-9 age group and the rate gradually increased up to 75.0% in the 50-59 age group. By sex, the rate was higher in the male than in the female in the 20-29 age group and over. 4) In the natural transition of the prevalence rate by age, the reduction rate of the infection during the past 16 years was greater in the younger age groups up to the 40-49 age group and reached the same level in the age group 50-59. Reduction was seen again in the age group over 60s. By sex, the reduction rate was greater in the female than in the male in the 20-29 age group and over. By area, the reduction rate was greater in the riverside delta area than in the inland area, particularly in the young age groups. 5) In the intensity of the infection among the cases, the mean egg out-put per mg feces per infected cases(EPmg) in the inhabitants was 6.3. EPmg of those of the river-side-delta area was 15.4 and that of the in-land was 2.8. On the other hand, in the schoolchildren, EPmg was 3.2, and no difference was seen between the two areas, the river-side-delta area and the inland area. 6) In the transition of the intensity of the infection by area, EPmg among the inhabitants inexplically increased from 7.8 in 1967 to 15.4 in 1983. This was probably caused by uneven specimen collection in the process of sampling the population. EPmg of the inhabitants in the inland area and those of the schoolchildren of both riverside delta and inland areas showed a similar decrease in the past 16 years. 7) The intensity of the infection by age showed a relatively low level in the 20-29 age group and below, and EPmg 5.1-9.5 was seen in the 30-39 age group and over. Sex, Epmg was 5.8 in the male and 4.7 the female. By in 8) In the transition of the intensity of the infection, EPmg decreased from 6.2 in 1967 to 5.4 in 1983. By age, in contrast to the figures of 1967 in which EPmg gradually increased with some fluctuation from 1.1 in the 0-4 age group to peak 10.5 in the 50-59 age group, in 1983 lower intensity of the infection was seen in the age group from 10-14 to 20-29 with the EPmg range of 0.6-2.7. 9) In the distribution of the clonorchiasis cases by the range of EPmg value, 43.2% of the cases were in 0.1 0.9 and 34.6% in 1.0-4.9. As a whole by cumulative percent, 44.6% of them were under 0.9 as light infection and 86.1% of them under 9.9 up to moderate infection. By sex, no difference was seen in Epmg. 10) In the transition of the distribution by the range of Epmg, the cases were distributed up to the range 80.0-99.9 in 1967 and to 60.0-79.9 in 1983. By cumulative percent, in the range of 0.1-0.9 and less, light infection, 34.3% of them were distributed in 1967 and 44.6% in 1983 with about 10% increase. In the range of 5.0-9.9 and less, up to moderate infection, 83.2% in 1967 and 86.1% in 1983 of the cases were seen, respectively. 11) The practice of raw freshwater fish consumption among the inhabitants seems to have decreased in recent years. Those who admitted to raw freshwater fish consumption in the last two years among the infected inhabitants were 59.3%, although 86.8% of them professed to have experience with raw freshwater fish consumption. 31.7% of those who have had experience of the raw freshwater fish consumption denied any further consumption in recent years. From an interview of 543 school-children, 24.1% of them admitted to an experience of raw freshwater fish consumption. However, those who have practised in the past two years comprized 17.9%. Those who denied raw freshwater fish consumption in recent years among those who had such experience were 26.0% out of 131 interviewed. The rate of raw freshwater fish consumption in both inhabitants and schoolchildren were higher in the male than in the female. On the contrary, the rate of those who did not practise in recent years among those who had experience of raw freshwater fish consumption was higher in the female than in the male. 12) The major reason for the reduction of raw freshwater fish consumption among the local inhabitants was the risk of the fluke infection. However, it has become apparent that such change of taste has resulted from water pollution impact which has affected throughout the areas of the freshwater systems in this locality since last several years. 13) In animal survey, Clonorchis infection was seen in 14.8% of 88 dogs examined and 3.7% of 27 house rats examined. It was noted that populations of dogs and cats have increased in the villages surveyed. Although the prevalence rate was lower in the present survey than those of 1967, the significance of the animals as the reservoir host has not changed. 14) Prevalence rate of Clonorchis infection by cercariae in the first intermediate host, Parafossarulus manchouricus, was 0.6% out of 517 snails examined. The infection rate was lower in comparison with 2.3% out of 2,124 examined in 1967. Moreover, sharp decreases in number and distribution of the intermediate host snails in many watershed areas of the huge freshwater systems in this locality seemed to reduce transmission of Clonorchis in connection with the intermediate host stage of its life cycle. 15) Clonorchis infection in the second intermediate fish hosts was relatively low. The mean number of Clonorchis metacercaria per fish in Pseudorasbora parva was 517 in 1983, whereas it was 1943 in 1968 through 1969. Environmental water pollution has also caused the decreased fish population density in these areas, and this has also apparently affected to the practice of raw freshwater fish consumption among the local inhabitants. 16) In conclusion, endemicity of Clonorchis infection in Gimhae Gum and delta area of the Nagdong River has sharply decreased during the past 16 years. The major cause of the regressive transition of the infection was the water pollution of the land water systems of this locality. The pollution has upset the ecosystems comprizing of the intermediate hosts of Clonorchis in many areas, and also affected to a significant extent to the discontinuance of the local inhabitants for raw freshwater fish consumption.

• Journal of Nutrition and Health
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• v.4 no.4
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• pp.39-46
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• 1971

Since ${\beta}-aminoethylphosphonic$ acid was discovered in the living organism, the biosynthesis and biological function of aminophosphonic acids have been extensively studied. The purpose of this project consists in the two parts: 1)the preparation of DL-1-amino-2-phenylethylphosphonic acid (Phenylalanine aminophosphonic acid) and DL-1-amino-3-methylbutyl-phosphonic acid (Isoleucine aminophosphonic acid) by the method of Chamber and Isbell. 2) the study of metabolism and biological functions of those synthetic materials by the animal experiment (white rats) The importance of this project proved to be the first experience fed by animals for the elucidation of biochemical and metabolic functions in the animal body. The following organic synthesis of DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenylethylphosphonic acid are studied. 1)Synthesis of DL-1-amino-3-methylbutylphosphonic acid a) Synthesis of Iso-butylbromide b) Synthesis of Ethyl iso-butylmalonate c) Synthesis of Iso-caproic acid d) Synthesis of $Ethyl-{\alpha}-bromo$ iso-caproate e) Synthesis of $Triethyl-{\alpha}-phosphono$ iso-caproate f) Synthesis of DL-1-amino-3-methylbutylphosphonic acid 2)Synthesis of DL-1-amino-2-phenylethylphosphonic acid a) Synthesis of Diethyl phosphite b) Synthesis of Ethylchloro acetate c) Synthesis of Triethyl phospho acetate d) Synthesis of Triethyl benzyl phospho acetate e) Synthesis of DL-1-amino-2-phenylethylphosphonic acid The synthetic compounds; DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenyl ethylphosphonic acid which are essential amino acid (isoleucine, phenylalanine)analogue are supplemented to the animal diet at the level of 0.2% and 0.4% for isoleucine analogue and 0.35% and 0.7% for phenylalanine analogue. The plain isoleucine and phenylalanine at the same level in the diet are fercilitated as comparable groups in this study. Two sets of experience including 100 male rats were carried out for seven weeks each total 14 weeks. During this period, urine samples, and each big organs were collected for the analysis of total nitrogen, phosphorus, and glycogen contents in the individual samples by Micro Kjeldahl Fisk & Subbarow and Nelson Somogye, method. 1) The result of the project a) The yield of DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenylethylphosphonic acid showed low tendency at the level of 12.5% and 20% Melting point of those two compounds were very high and the ${\alpha}-amino$ group in the synthetic compounds showed positive reaction with ninhydrin in the violet color. b) Ail the experimental groups included in this study revealed statistically no significant difference in the organ weight, total body nitrogen retention and urinary phosphorus excretion This means isoleucine aminophosphonic acid and Phenylalanine aminophosphonic acid were utilized in the body as much as the plain amino acids, isoleucine and phenylalanine did. c) The glycogen contents in the liver of the phenylalaine aminophosphonic acid gruop showed higher statistically significant(p<0.05) in the comparision with the group of the Phenylalanine and the Standard-2. It was noteworthy that the higher glycogen content in the liver might indicate the significance in the incorporation of phenylalanine aminophosphonic acid into the intermediate of tricarboxylic acid cycle as activated state.

• Korean Journal of Health Education and Promotion
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• v.2 no.1
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• pp.3-50
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• 1984

The levels of health knowledge, attitude and practice of housewives considerably effect to the health of households, communities and the nation. This study was designed to grasp the levels of health knowledge, attitude and practice of houswives and analyse the various factors effecting to health in order to provide health education services as well as materials for effective formulation and implementation of health policy to improve the health of the nation. This study has been conducted through interviews by trained surveyers for 4,281 housewives selected from 4,500 households throughout the country for 40 days during July 11-August 20, 1983. The results of survey were analysed by stepwise multiple regression and path analysis are summarized as follows; 1. Based on the measurement instrument applied to this study, the levels of health knowledge, attitude and practice of housewives were extremely low with 54.5 points out of 100 points in full. Higher level with 72 points and above was approximately 21 percent and lower level with 39 points and below was approx. 24 percent. The middle level was approx. 55 percent. In order to implement health programs successively, health education should be more strengthened and to improve the level of health knowledge, attitude and practice (KAP) of the nation, political consideration as a part of spiritual reformation must be concentrated on health. 2. The level of health knowledge indicated the highest points with 57.3 the level of attitude was the second with 55.0 points and the practice level was the lowest with 50.0 point. Therefore, planning and implementation of health education program must be based on the persuasion and motivation that health knowledge turn into practice. 3. Housewives who had higher level of health knowledge, showed their practice level was relatively lower and those who had middle or low level of it practice level was the reverse. 4. Correlations among health knowledge, attitude and practice (KAP) were generally higher and statistically significant at 0.1 percent level. Correlation between total health KAP level and health knowledge was the highest with r=.8092. 5. Health KAP levels showed significant differences according to the age, number of children, marital status, self-assessed health status and concern on health of the housewives interviewed (p<0.001) 6. Health KAP levels also showed significant differences according to the education level, economic status, employment before marriage and grown-up area of the housewives interviewed. (p<0.001) 7. Heath KAP levels showed significant differences according to health insurance benificiary and the existence of patients in the family. (p<0.001). 8. Health KAP levels showed significant differences according to distance to government organizations, schools, distance to health facilities, telephone possession rate, television possession rate, newspaper reading rate and activities of Ban meeting and Women's club. (p<0.001) 9. Health KAP levels showed significant differences according to electric mass communication media such as television, radio and village broadcasting etc. and printed media such as newspaper, magazine and booklets etc., IEC variables such as individual consultation and husband-wife communication, however, there was no significance with group training. 10. Health KAP of the housewives showed close correlation with personal characteristics variables, i.e., education level (r=.5302), age (r=-.3694) grown-up area (r=.3357) and employment before marriage. In general, correlation of health knowledge level was higher than the levels of attitude or practice. In case of health concern and health insurance, correlation of practice level was higher than health knowledge level. 11. Health KAP levels showed higher correlation with community environmental characteristics, Ban meeting and activity of Women's club, however, no correlation with New-village movement. 12. Among IEC variables, husband-wife communication showed the highest correlation with health KAP levels and printed media, electric mas communication media and health consultation in order. Therefore, encouragement of husband-wife communication and development of training program for men should be included in health education program. 13. Mass media such as electric mass com. and printed media were effective for knowledge transmission and husband-wife communication and individual consultation were effective for health practice. Group training was significant for knowledge transmission, however, but not significant for attitude formation or turning to health practice. To improve health KAP levels, health knowledge should be transmitted via mass media and health consultation with health professionals and field health workers should be strengthened. 14. Correlation of health KAP levels showed that knowledge level was generally higher than that of practice and recognized that knowledge was not linked with attitude or practice. 15. The twenty-five variables effecting health KAP levels of housewives had 41 per cent explanation variances among which education level had great contribution (β=.2309) and electric mass com. media (β=.1778), husband-wife communication (β=.1482), printed media, grown-up area, and distance to government organizations in order. Variances explained (R²) of health KAP were 31%, 15%, and 30% respectively. 16. Principal variables contributed to health KAP were education level (β=.12320, β=.1465), electric mass comm. media (β=.1762, β=.1839), printed media, (β=.1383, β=.1420) husband-wife communication (β=.1004, β=.1067), grown-up area and distance to government organizations, in order. Since education level contributes greatly to health KAP of the housewives, health education including curriculum development in primary, middle and high schools must be emphasized and health science must be selected as one of the basic liberal arts subject in universities. 17. Variences explained of IEC variables to health KAP were 19% in total, 14% in knowledge, 9% in attitude, and 10% in health practice. Contributions of IEC variables to health KAP levels were printed media (β=.3882), electric mass comm media (β=.3165), husb-band wife com. (β=.2095,) and consultation on health (β=.0841) in order, however, group training showed negative effect (β=-.0402). National fund must be invested for the development of Health Program through mass media such as TV and radio etc. and for printed materials such as newspaper, magazines, phamplet etc. needed for transmission of health knowledge. 18. Variables contributed to health KAP levels through IEC variables with indirect effects were education level (Ind E=0.0410), health concern (Ind E=.0161), newspaper reading rate (Ind E=.0137), TV possession rate and activity of Ban meeting in order, however, health facility showed negative effect (Ind E=-.0232) and other variables showed direct effect but not indirect effect. 19. Among the variables effecting health KAP level, education level showed the highest in total effect (TE=.2693) then IEC (TE=.1972), grown-up city (TE=.1237), newspaper reading rate (TE=.1020), distance to government organization (TE=.095) in order. 20. Variables indicating indirect effects to health KAP levels were; at knowledge level with R²=30%, education level (Ind E=.0344), newspaper reading rate (Ind E=.0112), TV possession rate (Ind E=.0689), activity of Ban meeting (Ind E=.0079) in order and at attitude level with R²=13%, education level (Ind E=. 0338), activity of Ban meeting (Ind E=.0079), and at practice level with R²=29%. education level (Ind E=.0268), health facility (Ind E=.0830) and concern on health (Ind E=.0105). 21. Total effect to health KAP levels and IEC by variable characteristics, personal characteristics variables indicated larger than community characteristics variables. 22. Multiple Correlation Coefficient (MCC) expressed by the Personal Characteristic Variable was .5049 and explained approximately 25% of variances. MCC expressed by total Community environment variable was .4283 and explained approx. 18% of variances. MCC expressed by IEC Variables was .4380 and explained approx. 19% of variances. The most important variable effected to health KAP levels was personal characteristic and then IEC variable, Community Environment variable in order. When the IEC effected with personal characteristic or community characteristic, the MCC or the variances were relatively higher than effecting alone. Therefore it was identified that the IEC was one of the important intermediate variable.