• Title/Summary/Keyword: physical conditions

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Experimental Study on the Geochemical and Mineralogical Alterations in a Supercritical CO2-Groundwater-Zeolite Sample Reaction System (초임계 이산화탄소-지하수-제올라이트 시료 반응계에서의 지화학적 및 광물학적 변화에 관한 실험적 연구)

  • Park, Eundoo;Wang, Sookyun;Lee, Minhee
    • Economic and Environmental Geology
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    • v.47 no.4
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    • pp.421-430
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    • 2014
  • In this study, a series of autoclave experiments were conducted in order to investigate the geochemical and mineralogical effects of carbon dioxide on deep subsurface environments. High pressure and temperature conditions of $50^{\circ}C$ and 100 bar, which are representative environments for geological $CO_2$ sequestration, were created in stainless-steel autoclaves for simulating the interactions in the $scCO_2$-groundwater-mineral reaction system. Zeolite, a widespread mineral in Pohang Basin where many researches have been focused as a candidate for geological $CO_2$ sequestration, and groundwater sampled from an 800 m depth aquifer were applied in the experiments. Geochemical and mineralogical alterations after 30 days of $scCO_2$-groundwater-zeolite sample reactions were quantitatively examined by XRD, XRF, and ICP-OES investigations. The results suggested that dissolution of zeolite sample was enhanced under the acidic condition induced by dissolution of $scCO_2$. As the cation concentrations released from zeolite sample increase, $H^+$ in groundwater was consumed and pH increases up to 10.35 after 10 days of reaction. While cation concentrations showed increasing trends in groundwater due to dissolution of the zeolite sample, Si concentrations decreased due to precipitation of amorphous silicate, and Ca concentrations decreased due to cation exchange and re-precipitation of calcite. Through the reaction experiments, it was observed that introduction of $CO_2$ could make alterations in dissolution characteristics of minerals, chemical compositions and properties of groundwater, and mineral compositions of aquifer materials. Results also showed that geochemical reactions such as cation exchange or dissolution/precipitation of minerals could play an important role to affect physical and chemical characteristics of geologic formations and groundwater.

Studies on the Biological Control of Pine Caterpillar (Dendrolimus spectabilis Butler) by Red Wood Ants (Formica rufa truncicola var. yessoensis Forel) (불개미를 이용한 송총의 생물적방제에 관한 연구)

  • Kim Chang Hyo;Choi Jin Sik
    • Korean journal of applied entomology
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    • v.15 no.1 s.26
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    • pp.7-16
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    • 1976
  • In order to increase utility efficiency of red wood ants, Formica rufa truncicola var. yessonesis Forel as a resource of natural enemy of pine caterpillar, Dendrolimus spectabilis Butler, by finding out ecological and environmental factors in the habitat of red wood ants, the nest distribution and its density in habitat, plant distribution and density, stand-density of red pine, nest building and fixing plants, relative humidity of surface soil, physical and chemical natures of soil, and breeding rate were examined. The obtained results are summarized as follows: 1. The nest of red wood ants was densely distributed, in the lower-and middle top of mountain but no nest was found in the top. 2. The economical distribution of nest of habitat was estimated as $2.85/m^2$ and the lowest density as $1.93/m^2$ and these estimation lead us to confirm that pine caterpillar could be controlled. 3. The ecological characteristics of habitat seemed to be represented as higher stand-density of red pine of 10-20 years of age with large areas of eroded land under trees. The major grasses prevailing in this area were Andropogon brevifolius. Arundinella hirta, Miscanthus purpurasens, Eulia speciosa, Themeda japonica, Cymbopogon goeringii, and Eccoilpus cotulifer 4. Red wood ants seemed to build the nest by using red pine, Arundinella hirta, Miscanthus purpurascens, Themeda japonica or Cymbopogon goeringii as a fixing plant. 5. The limited point of humidity percent in habitat of red wood ants was estimated as $76\%$ during the acting period of May to September and as $72\%$ during pre-period of hibernation of October to November. 6. Soil analysis in habitating region showed higher concentration of organic matters and lower concentration of calcium and magnesium, and habitat was largely composed of silt and fine sand rather than coarse sand. 7. When the separated colony was transplanted to non-habitating red pine forest that seemed to have the similiar conditions as those of habitat, propagation and establishment of nest was possible.

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Studies on the Seasonal Increase of the Population of the Smallerbrown Planthopper, Laodelphax striatellus(Fallen) (애멸구의 세대별 증식동태에 관한 연구 -기주식물의 종류와 생육단계와 증식과의 관계-)

  • Hyun Jai Sun;Woo Kun Suk;Ryoo Mun Il
    • Korean journal of applied entomology
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    • v.16 no.1 s.30
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    • pp.13-19
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    • 1977
  • The smaller brown planthopper overwinters mostly as the fourth instar nymph. The emerged adult disperses to winter barley or wheat plants. The adult of the first generation disperses into the rice field, and spends three generations in the rice field. The population densities of the adults of the first generation and the overall density of the second generations are the most important in relation to the incidents of the rice stripe disease which is transmitted by this insects. This study was intended to analyse the population increases in these important generations in relation to the kind and the different growing stage of the host plants. The insects were reared on potted host plants of different growing stage in the insect cages. The population increases of the insects in the cages were compared with those on the rice seedlings in the laboratory. The results are as follows: 1. The average longevities of the adults of the generations were 13.4 days for the overwintered, 12.9 days for the first, and 10.2 days for the second generation, and showed no significant differences between the generations even they seemed to be shorter than normal condition probably caused by the frequent disturbance at the time of food renewal in 2 or 3 days. 2. When they were reared on the rice seedling, the average numbers of the eggs per female were 131.2 for the overwintered generation, 124.9 for the first generation grown on the barley, and 142.3 for the second generation grown on rice, and shelved no significant differences between the generations. More than $90\%$ of the eggs were laid within 3 weeks. 3. The hatchabilities of the eggs laid on the rice seedling in laboratory were $77.4\%$ for the first generation, $93.1\%$ for the second generation and $62.1\%$ for the third generation. The estimated hatchabilities of the eggs were $67.5\%$ for the first generation, $84.1\%$for the second generation, and $21.9\%$ for the third generation with the growing plants on the plots. The hatchability on the eggs laid by the adults infested on the barley on May 17 was $13.5\%$ compared with $67.5\%$ for the eggs laid by those infested on barley in late April. 4. The average total nymphal periods were 19.4 days for the first generation, and 13.3 days for the second generation in the laboratory and the mortalities of the nymphs seemed to related with the growing stages of the host plants. 5. With the pot experiments, the average per cents of the emerged adults were $37.2\%$ for the first generation, $55.3\%$ for the second generation, and $11.6\%$, for the third generation. The average numbers of the emerged adults were $7.4\%$ for the pots infested on the barley on May 17, instead of $37.2\%$ adults for those infested in late April. 6. From above results, it may suggest that the innate qualities of the insect are not significantly different between generations, and the differences in the increase of the population for the generations might effected considerably by the differences in the physiological conditions of tile host plant, besides the differences in physical and other biological factors.

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<Field action report> Development and Application of Participatory Action Oriented Training(PAOT) for Improvement of Agricultural Working Environment in Korea (<사례보고> 농작업 환경개선을 위한 한국형 참여형 개선활동 교육(PAOT)의 개발과 실제 적용 사례)

  • Kim, J.S.;Woo, K.H.;Min, Y.S.;Kim, B.K.;Choi, K.S.;Park, K.S.
    • Journal of agricultural medicine and community health
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    • v.35 no.4
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    • pp.417-427
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    • 2010
  • Objectives: This study was conducted to develop a Korean version of the Participatory Action Oriented Training (PAOT) program and training materials for improvement of agricultural working environments. Methods: The PAOT manual and checklist were developed on the basis of the original English version of the training materials, a questionnaire survey of agricultural health and safety professionals, and a brainstorming conference. Good example pictures were collected through visits to agricultural workers' houses, and an easily understandable picture was drawn by an animation specialist. A PAOT action manual and five types of action checklists were developed for use in different agricultural environments. Each action checklist contained six categories and 38 items of agricultural health and safety principles; the six categories were material storage and handling, work stations and tools, machine safety, physical environment, working schedule and organization, and basic health and safety management. Incorporating these training materials, a one-day Korean PAOT program was developed. Results: Among 307 candidate agricultural workers from four rural Korean villages, 94 workers (59 males, 35 females) participated in a PAOT from July 2007 to Oct 2008. The PAOT program was successful and the mean self-estimated satisfaction score of the participants was greater than 90%. Conclusions: A Korean PAOT program and training materials were successfully developed and applied to Korean agricultural workers. Although more studies are needed, it is expected that PAOT will greatly contribute to the improvement of agricultural working conditions and health and safety through the use of agricultural workers' self initiatives.

A Study on Improvement Examination Standard for the Limit of changing Current State of the Cultural Properties (문화재 유형별 현상변경 검토기준 마련 연구)

  • Cho, Hong-Seok;Park, Hyun-Joon;Lee, You-Beom;Lee, Cheon-Woo;Kim, Chul-Ju;Park, Jung-Seop;Kim, Sang-Dong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.4
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    • pp.148-165
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    • 2015
  • The Cultural Properties Protection Law Act 1962 has been achieving its role for systematic preservation, management and application of the cultural heritage under rapid economic growth circumstances through continuing revisions. Introduced the influence review system for cultural heritages in 2000, and legislated the guideline for the state-change allowance standard for the National Cultural Heritage in 2006 in specific, the law has been contributing significantly for the cultural properties and historical/cultural environment preservation, along with increase in administrative efficiency and improvement on settlement environment. However, increase in public awareness about the cultural property's value and the needs for the local revitalization by utilizing the heritages, while some allowance standard not peoperly delivering the surrounding conditions, such as the value of the properties and their substantial characteristics, land utilization, etc. being applied, complaints from the local residents are increasing continuously. Thus this research focuses on clear vision/value of the heritage and apply them to create the review criteria for the state-change allowance per heritages. Here we set the Focus of Landscape Management Indicators in order to actively preserve and manage the physical characteristics and the native value by analyzing the Cultural Heritage Protection Laws and related guidelines, manuals and research papers, and redesign the cultural propertiy's classification scheme and propose the Review Standard for state-change from the view point of changing the current state. With this research, we expect increase in the satisfaction for the Property management system with public understanding promotion regarding the Standards by applying the reviewed state-change allowance Standards, white securing the consistency for the review criteria as well as the systematic management of historical/cultural environment with their typification characteristics and the value for short-term.

A Study on the Mobile Medical Service Program -Based on the Community Diagnosis of a Remote Farm Area- (순회진료사업(巡回診療事業)의 문제점(問題点)과 개선방향(改善方向) (일부(一部) 무의지역에 대(對)한 지역사진단(地域社診斷)을 중심(中心)으로))

  • Park, Hung-Bae;Choi, Dong-Wook
    • Journal of Preventive Medicine and Public Health
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    • v.11 no.1
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    • pp.86-97
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    • 1978
  • The mobile medical service has been operated for many years by a number of medical schools and hospitals as a most convenient means of medical service delivery to the people residing in such area where the geographical and socioeconomic conditions are not good enough to enjoy modern medical care. Despite of official appraisal showing off simply with numbers of outpatients treated and medical persons participated, however, as well recognized, the capability (in respect of budget, equipment and time) of those mobile medical teams is so limitted that it often discourages the recipients as well as medical participants themselves. In the midst of rising need to secure medical service of good quality to all parts of the country, and of developing concept of primary health care system, authors evaluated the effectiveness of and problems associated with mobile medical servies program through the community diagnosis of a village (Opo-myun, Kwangju-gun) to obtain the information which may be halpful for future improvement. 1. Owing to the nationwide Sae-Maul movement powerfully practiced during last several years, living environment of farm villages generally and remarkably improved including houses, water supply and wastes disposal etc. Neverthless, due to limitations in budget time and lack of knowledge (probably the most important), these improvements tend to keep up appearances only and are far from the goal which may being practical benefit in promoting the health of the community. 2. As a result of intensive population policy led by the government since 1962, there has been considerable advances in understanding and the rate of practicing family planning through out the villages and yet, one should see many things, especially education, to be done. Fifty eight per cent of mothers have not received prenatal check and the care for most (72%) delivery was offered by laymen at home. 3. Approximately seven per cent of the population was reported to have chronic illness but since only a few (practically none) of the people has had physical check up by doctors, the actual prevalence of chronic diseases may reach many times of the reported. The same fact was observed also in prevalence of tuberculosis; the patients registered at local health center totaled 31 comprising only 0.51% while the numbers in two neighboring villages (designated as demonstration area of tuberculosis control and mass examination was done recently) were 3.5 and 4.0% respectively. Prevalence rate of all dieseses and injuries expereinced during one month (July, 1977) was 15.8%. Only one tenth of those patients received treatment by physicians and one fifth was not treated at all. The situation was worse as for the chronic patients; 84% of all cases either have never been treated or discontinued therapy, and the main reasons were known to be financial difficulty and ignorance or indifference. 4. Among the patients treated by our mobile clinic, one third was chronic cases and 45% of all patients, by the opinion of doctors attended, were those who may be treated by specially trained nurses or other paramedics (objects of primary care). Besides, 20% of the cases required professional managements of level beyond the mobile team's capability and in this sense one may conclude that the effectiveness (performance) of present mobile medical team is quite limitted. According to above findings, the authors would like to suggest following for mobile medical service and overall medicare program for the people living in remote country side. 1. Establishment of primary health care system secured with effective communication and evacuation (between villages and local medical center) measures. 2. Nationwide enforcement of medical insurance system. 3. Simple outpatient care which now constitutes the main part of the most mobile medical services should largely be yielded up to primary health care unit of the village and the mobile team itself should be assigned on new and more urgent missions such as mass screening health examination of the villagers, health education with modern and effective audiovisual aids, professional training and consultant services for the primary health care organization.

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Geochemical Characteristics of Soil Solution from the Soil Near Mine Tailing Dumps and the Contamination Assessment in Duckum Mine (토양수의 자구화학특성에 따른 금속폐광산 광미야적장주변 토양오염평가: 덕음광산)

  • 이상훈;정주연
    • Economic and Environmental Geology
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    • v.37 no.1
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    • pp.61-72
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    • 2004
  • The soil samples were collected from the paddy field near the mine tailing dumps in the abandoned Duckum mine in Korea. In the laboratory, the soil solution was extracted from the soil using centrifuge, and analysed for the chemical composition. Physical and chemical soil properties were also analysed. Kaolinite is the main clay minerals in the paddy soil and the CEC value is therefore relatively low. Nearly all soil samples show enrichment in their trace elemental concentrations(Cd, Cu, Pb and Zn) compared with natural background level. Some soil samples exceed the soil remediation intervention values for Cd, Pb and Zn and target value for Cu, when compared with Dutch standard, whereas As, Ni and Cr are in normal range. Lead concentrations in some samples near the mine tailing dumps also exceed the standard for remediation act for agricultural area set by Korean soil conservation law. The trace elemental concentrations are higher in the paddy soil nearer the mine tailing dumps and lower for the samples from distance. Similar trend with distance is found for the soil solution chemistry but the decrease with distance from the mine tailing dumps are sharper than the changes in soil chemistry. Cadmium, Cu and Pb concentrations in the soil solution are very low, ranging from a tenth and hundredths to a maximum of several mg/l, whereas their concentrations in soils are highly enriched for natural background. Most of the trace elements are thought to be either removed by reduced iron sulphides or iron oxides, depending on the redox changes. Geochemical equilibrium modelling indicate the presence of solubility controlling solid phases for Cd and Pb, whereas Zn and Cu might have been controlled by adsorption/desorption processes. Although pollutants migration through solution phase are thought to be limited by adsorption onto various Fe, Mn solid phases, the pollutants exist as easily releasable fractions such as exchangeable site. In this case, the paddy soil would act as pollutant pool, which will supply to plants in situ. whenever the geochemical conditions favour.

Effects of Alcohol on Psychomotor Performance and Subjective Assessments In Normal Adults with Variation of Acetaldehyde Dehydrogenase I (정상성인에서 ALDH-I의 변이가 알콜의 정신운동성 수행과 주관적 평가에 미치는 영향)

  • Yoon, Bo Hyun;Yoon, Jin Sang
    • Korean Journal of Biological Psychiatry
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    • v.3 no.2
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    • pp.222-239
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    • 1996
  • The purpose of this study was to evaluate the effects of alcohol on the psychomotor performance and subjective assessment in healthy Korean adults with acetaldehyde dehydrogenase I(ALDH-I) isozyme variance. A total of 20 male subjects, half with active ALDH-I and the other half with inactive ALDH-I, were selected through both a self-reporting questionnaire examining alcohol sensitivity and the Higuchi's ethanol patch test detecting ALDH-I deficiency. In a doule-blind, placebo-controlled cross-over design, each subject consumed four doses of alcohol(0.25, 0.5, 0.75, 1.0g/kg) and placebo on five separate occasions at weekly intervals, Treatment order was fully balanced using a $5{\times}5$ Latin square, Psychomotor performance tests[coritical flicker fusion threshold(CFF) and choice reaction time(CRT)] and self-estimate questionnaires were conducted at baseline and at time points of 20, 40, 60, 90, 120, 150, 180 minutes after consuming the test drug for 20 minutes, Blood alcohol concentrations(BACs) using breath analyzer were measured at baseline and at time points of 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180 minutes after drinking, The BACs and the mean changes in the psychomotor performances and subjective assessments from pre-alcohol baseline, were compared between the two groups. The findings were summarized as follows : 1) BACs were tended to be higher in the inactive group than the active in all of the four alcohol doses. However significant group differences were only after the 0.5g/kg dose of alcohol. 2) The inactive group showed significant impairment in CFFT at most time points alter 0.75 and 1.0g/kg doses of alcohol. 3) In CRT, total reaction time(TRT) significantly prolonged in the inactive group than the active group at 20 minutes after 0.25 and 1.0g/kg doses of alcohol and at 40, 60, 90 minutes alter 0.75g/kg dose of alcohol. In the inactive group, recognition time component significantly increased at 20, 60, 90 minutes after 1.0g/kg dose of alcohol, while movement time component significantly increased at 40, 60 minutes after 0.75g/kg dose of alcohol. 4) Subjective evaluation of the effect of alcohol revealed that physical and mental conditions as well as a self-estimate of the effects of alcohol on performance were significantly worse in the inactive group than the active at some time points alter all of the lour alcohol doses, wihch were more pronounced after 0.75 and 1.0g/kg doses of alcohol. 5) Most of the group differences mentioned above, still remained statistically significant after BAC was entered as a covariate, These findings demonstrated that the alcohol sensitivity is higher in individuals with inactive ALDH-I than those with active ALDH-I both on the subjective assessments and the objective psychomotor performances. Furthermore, these results suggest thai the alcohol sensitivity may be determined by acetaldehyde concentration rather than BAC per se. In future studies, after more accurate genotyping for ALDH-I, the relationships between BAC, acetaldehyde concentration and alcohol sensitivities should be clearly defined.

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Ecological Health Assessments on Turbidwater in the Downstream After a Construction of Yongdam Dam (용담댐 건설후 하류부 하천 생태계의 탁수영향 평가)

  • Kim, Ja-Hyun;Seo, Jin-Won;Na, Young-Eun;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.40 no.1
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    • pp.130-142
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    • 2007
  • This study was to examine impacts of turbid water on fish community in the downstream of Yongdam Dam during the period from June to October 2006. For the research, we selected six sampling sites in the field: two sites were controls with no influences of turbid water from the dam and other remaining four sites were the stations for an assessment of potential turbid effects. We evaluated integrative health conditions throughout applications of various models such as necropsy-based fish health assessment model (FHA), Index of Biological Integrity (IBI) using fish assemblages, and Qualitative Habitat Evaluation Index (QHEI). Laboratory tests on fish exposure under 400 NTU were performed to find out impact of turbid water using scanning electron microscope (SEM). Results showed that fine solid particles were clogging in the gill in the treatments, while particles were not found in the control. This results indicate that when inorganic turbidity increases abruptedly, fish may have a mechanical abrasion or respiratory blocking. The stream health condition, based on the IBI values, ranged between 38 and 48 (average: 42), indicating a "excellent" or "good" condition after the criteria of US EPA (1993). In the mean time, physical habitat condition, based on the QHEI, ranged 97 to 187 (average 154), indicating a "suboptimal condition". These biological outcomes were compared with chemical dataset: IBI values were more correlated (r=0.526, p<0.05, n=18) with QHEI rather than chemical water quality, based on turbidity (r=0.260, p>0.05, n=18). Analysis of the FHA showed that the individual health indicated "excellent condition", while QHEI showed no habitat disturbances (especially bottom substrate and embeddeness), food-web, and spawning place. Consequently, we concluded that the ecological health in downstream of Yongdam Dam was not impacted by the turbid water.

A study on the intake of foods causing dental caries and the effect of nutrition education for primary students (초등학교 아동의 치아우식성 식품섭취 및 영양교육 효과에 관한 연구)

  • 김혜영;원복연;류시현
    • Korean journal of food and cookery science
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    • v.18 no.6
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    • pp.704-715
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    • 2002
  • This study intended to compare dietary and snack habits of primary students in the schools providing and non-providing lunch to clarify the correlation between those conditions and the occurrence of dental caries. Furthermore, this study also focused on evaluating educational effects by providing children with nutritional education program. 1. As a result of dietary habit analysis, it was found that children from the school providing lunch were better in terms of breakfast regularity, eating speed. optimum amount of intake, and meal time regularity than those from the school non-providing lunch. In particular, it was noted that children from the school providing lunch took a little more meat, fish, seaweed and milk or dairy products than those from school non-providing lunch. Thus, it could be assumed hat children provided with lunch have more reasonable dietary habit than those without lunch program. In general, it was found that there was a slight positive change in children's dietary habit after nutritional instruction than before, suggesting that the nutritional education had effects on improving their dietary habit. 2. It was found that primary students often took snacks causing dental caries such as caramel, chocolate, sweets and biscuits, and children from the school providing lunch were more willing to reduce those snacks upon recognizing the causes of dental caries than those from the school non-providing lunch. For the children who chewed gum with physical cleansing effects, it was shown that the highest frequency wat twice or three times a week. Moreover, the ratio of children who took snacks following dinner which might affect their dental caries and the ratio of children who selected snacks because of TV commercial were both reduced after nutritional education. Also the consumption of detergent foods like vegetable, fruit, protein. seaweed. milk or dietary products after nutritional education was increased. 3. It was found that children from the school providing lunch took more often all food groups except for food group IV affecting dental caries than those from the school non-providing lunch. The average number of consuming foods which cause dental caries was 5.04 times per person a day, and most of those were rather taken by liquid than solid food. The average eating times of rinsing foods which kill the bacteria on the surface of teeth and prevent from dental caries, was 9.33 for a person a day, which was a little higher than recommended time. Exposed time for dental caries for a person a day was 100.9 min, of which liquid dental caries was 56.2 min and solid dental caries was 44.6 min, suggesting that liquid food had a high potential to cause dental caries.