• Title/Summary/Keyword: Urban environmental problem

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Comparative Study on the Methodology of Motor Vehicle Emission Calculation by Using Real-Time Traffic Volume in the Kangnam-Gu (자동차 대기오염물질 산정 방법론 설정에 관한 비교 연구 (강남구의 실시간 교통량 자료를 이용하여))

  • 박성규;김신도;이영인
    • Journal of Korean Society of Transportation
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    • v.19 no.4
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    • pp.35-47
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    • 2001
  • Traffic represents one of the largest sources of primary air pollutants in urban area. As a consequence. numerous abatement strategies are being pursued to decrease the ambient concentration of pollutants. A characteristic of most of the these strategies is a requirement for accurate data on both the quantity and spatial distribution of emissions to air in the form of an atmospheric emission inventory database. In the case of traffic pollution, such an inventory must be compiled using activity statistics and emission factors for vehicle types. The majority of inventories are compiled using passive data from either surveys or transportation models and by their very nature tend to be out-of-date by the time they are compiled. The study of current trends are towards integrating urban traffic control systems and assessments of the environmental effects of motor vehicles. In this study, a methodology of motor vehicle emission calculation by using real-time traffic data was studied. A methodology for estimating emissions of CO at a test area in Seoul. Traffic data, which are required on a street-by-street basis, is obtained from induction loops of traffic control system. It was calculated speed-related mass of CO emission from traffic tail pipe of data from traffic system, and parameters are considered, volume, composition, average velocity, link length. And, the result was compared with that of a method of emission calculation by VKT(Vehicle Kilometer Travelled) of vehicles of category.

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Application of Liriope platyphylla, Ornamental Korean Native Plants, for Contaminated Soils in Urban Areas (도시 내 중금속 오염지의 관상식물로서 자생 맥문동(Liriope platyphylla)의 적용성 평가)

  • Ju, Jin-Hee;Yoon, Yong-Han
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.5
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    • pp.81-87
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    • 2014
  • Heavy metal pollution is a widespread global problem causing serious environmental concern. Heavy metals such as Cd, Pb, and Zn can induce toxicity in all organisms if the soil levels of contaminants reach critical values. The aim of the present study was to examine the application of Liriope platyphylla, an ornamental Korean native plant with great potential for contaminated soil in urban areas, to determine tolerance for Cd, Pb, and Zn. Plants were grown in amended artificial soil with Cd, Pb, and Zn at 0, 100, 250, and $500mg{\cdot}kg^{-1}$ for 7 months. The length of leaf, width of leaf, total leaf number, dead leaf number, new leaf number, chlorophyll contents, and ornamental value were monitored from May to August, during growth the period. The relative leaf length and leaf width displayed rapidly decreasing tendencies with an increasing Cd concentration beginning from 4 months after planting. The same decreasing tendency was observed in total leaf number, new leaf number, chlorophyll contents, and ornamental values showed a trend of Control> $Cd_{100}$ > $Cd_{250}$ > $Cd_{500}$. In Pb concentration treatments, the relative leaf length and leaf width were significantly lower in plants grown at $250mg{\cdot}kg^{-1}$ and $500mg{\cdot}kg^{-1}$ as compared to the Control, $100mg{\cdot}kg^{-1}$. The total leaf number, new leaf number, and dead leaf number did not show significant difference among treatments in Control and $Pb_{100}$ but chlorophyll contents and ornamental value decreased with increasing Pb supply concentration treatments. However, in Zn supply treatments, the relative leaf length was higher at $100mg{\cdot}kg^{-1}$ than the Control, $250mg{\cdot}kg^{-1}$, $500mg{\cdot}kg^{-1}$, but the relative leaf width decreased compared to the Control, $Zn_{100}$, $Zn_{250}$, and $Zn_{500}$. The total leaf number, dead leaf number, new leaf number, and ornamental value showed the lowest value in plants grown in $Zn_{500}$ treatment but no significant differences were found among other treatments.

Difference of Place Identity Perception and Landscape Preference between Residents and Tourists in Ihwa-dong Mural Village (이화동 벽화마을 주민과 관광객간의 장소 정체성 인식 및 경관 선호 차이에 관한 연구)

  • Kim, Yelim;Son, Yong-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.1
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    • pp.105-116
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    • 2017
  • Murals in villages revitalize communities and spaces, and are economically efficient. Central and local governments are therefore actively undertaking Mural Village Projects but there are some issues and concerns about the projects for the provision of uniformed landscapes for the regions that are the result of a short-term completion of projects, and instead of cohesion, cause destruction of place identities. In addition, the problem of sustainable landscape management that is the result of low community involvement can be pointed out because the murals are products of government-led projects. The study covered the context of landscape and space change processes from a critical perspective, and focused on Ihwa-dong Mural Village, which is considered the first mural village in Korea and has begun to undergo drastic changes due to attention received from media. The purposes of this study are as follows. First, the study provides data about difference of place identity perception and landscape preference between residents and tourists in Ihwa-dong Mural Village. Second, this paper evaluates the current Mural Village Projects and finds alternative directions to improve the projects by using these data. This paper analyzed tourist hot spots in Ihwa-dong Mural Village by using SNS analysis, a field study and focus group interviews. The difference of place identity perception and landscape preference was examined among three groups: residents, new residents who are invited by Mural Village Projects, and tourists. This study showed that many tourists are focused on landscape areas that were not intentionally constructed projects. In addition, the locations of preferred landscapes and stores overlapped. Meanwhile, using qualitative data analysis, it was found that residents perceived the area as being an under-privileged location, while the murals, a non-daily landscape, largely affected place identity perception of new residents and tourists. For landscape preference, tourists preferred outdoor rest areas, while new residents and residents preferred less. Additionally, new residents and tourists preferred an area's night view while residents made no mention of this. Related to the direction of the projects, three groups showed their dependence on the government. This empirical study is significant from a participatory design perspective and in analyzing the issues for mural villages' landscapes, which are spreading across the nation and proceeding without criticism in urban regeneration. Implications for urban planners and suggestions for the future projects are given.

Contents of Health Education for Pupils and the Perceptibility after Graduation of Primary School (국민학교(國民學校) 교과서내(敎科書內)의 보건교육내용(保健敎育內容) 및 그 습득도(習得度))

  • Jeon, Bo-Yoon;Kim, Doo-Hie
    • Journal of Preventive Medicine and Public Health
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    • v.18 no.1
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    • pp.99-112
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    • 1985
  • It was measured to check the state of health education by the survey of the items related to the health with the first grade of students in middle school who mastered elementary courses. Totally 50 questions, which were selected from Standard and Dong-A reference books, were given to teachers and have got answered by the students who were totally 959(491 from urban areas and 468 from rural areas). It's done just after they entered middle school for a month, from April 10 to may 10, 1984. There were totally 782 items of health in all subjects of all grades. In contents, the most cases were about mental and emotional health(17.7%), exercise and rest (15.1%), environmental health, health life, personal health care, nutrition and foods, social health and organization, physiology and anatomy, statistics of public health population problem, disease and care, food sanitation, school health, parasitic and communicable disease control, eugenics and heredity(0.4%), etc were followed. In subjects, Korean language had 44.7% of mental and emotional health in 114 cases, arithmetics 46.4% of statistics of public health in 26, sociology, 23.1% of environmental health in 118, natural science, 60.1% of physiology and anatomy in 30, ethics, 40.3% of mental and emotional health in 176, music, 21.8% of mental and emotional health and accidents in 23, art, 42.9% of exercise and rest in 28, physical education, 38.6% of exercise and rest in 201, practical course, 36.2% of nutrition and foods in 61, and there was nothing but only one case in Korean history. Subjects in total cases of health informing items are below: Physical education 25.8, ethics 22.5%, sociology 15.1%, Korean language 14.6%, practical course 7.8%, natural science 3.8%, art 3.6%, arithmetics 3.3%, music 2.9%, Korean history 0.6%. Grades in total cases of health informing items are belows: the sixth grade 29.1%, the fourth grade 21.2%, the fifth grade 18.9%, the third grade 11.6%, the first grade 11.5%, the second grade 7.7%. The sections related to health matters were average 35.4%. According to the grades, the fourth and the sixth grade were 38.2% each other, the highest, and the second grade was 29.3%, the lowest. All scetions in physical education included them. The acceptability to the knowledge for health was belows: 56.3% in urban students and 53.9% in rural students. There was some difference in acceptability between two parties (p<0.005).

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Estimating the Dimension of a Crosswalk in Urban Area - Focusing on Width and Stop Line - (도시부 횡단보도 제원 산정에 관한 연구 - 폭과 정지선을 중심으로 -)

  • Kim, Yoomi;Park, Jejin;Kwon, Sungdae;Ha, Taejun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.5
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    • pp.847-856
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    • 2016
  • Recently, with a high level of economic growth, rapid urbanization, population, environment and housing problems were accompanied in Korea. In particular, the traffic problem has become a serious social problem. As the current transportation policy has been carried out, concentrating on traffic flow, in 2015, death rate for pedestrians while walking (1,795 persons) is 38.8% compared to entire death rate in car accident (4,621 persons), so there is need to solve it. Although, crosswalk should make pedestrian cross it safely, it has been made on the basis of the width of road without exact standard for current width of the crosswalk and the location of stop line. Moreover, in the area around many campuses or commercial facilities, crosswalks are set with not considering pedestrian passage, but designed uniformly. Therefore, the purpose of this study is to estimate reasonable dimension of crosswalk considering pedestrian traffic and walking speed and it makes the accident rate lower in the crosswalk, which has a lot of problems including decisions of vehicle traffic signal time, lack of pedestrian's signal timing, pedestrian's crossing of long-distance. The following are the methodology of the study. Firstly, for crosswalk calculation of specifications, examination relating existing regulations and researches dealing with crosswalk, pedestrians and stop line is needed. After analyzing problems of current width of crosswalk and stop line, present the methodology to calculation of specifications and basing on these things, calculation of specifications for crosswalk will be decided. In conclusion, the calculation of specification and improvement of stop line for crosswalk laid out in this study are expected to be utilized as base data in case of establishing relevant safety facilities and standards.

Future Direction of National Health Insurance (국민건강보험 발전방향)

  • Park, Eun-Cheol
    • Health Policy and Management
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    • v.27 no.4
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    • pp.273-275
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    • 2017
  • It has been forty years since the implementation of National Health Insurance (NHI) in South Korea. Following the 1977 legislature mandating medical insurance for employees and dependents in firms with more than 500 employees, South Korea expanded its health insurance to urban residents in 1989. Resultantly, total expenses of the National Health Insurance Service (NHIS) have greatly increased from 4.5 billion won in 1977 to 50.89 trillion won in 2016. With multiple insurers merging into the NHI system in 2000, a single-payer healthcare system emerged, along with separation policy of prescribing and dispensing. Following such reform, an emerging financial crisis required injections from the National Health Promotion Fund. Forty years following the introduction of the NHI system, both praise and criticism have been drawn. In just 12 years, the NHI achieved the fastest health population coverage in the world. Current medical expenditure is not high relative to the rest of the Organization for Economic Cooperation and Development. The quality of acute care in Korea is one of the best in the world. There is no sign of delayed diagnosis and/or treatment for most diseases. However, the NHI has been under-insured, requiring high-levels of out-of-pocket money from patients and often causing catastrophic medical expenses. Furthermore, the current environmental circumstances of the NHI are threatening its sustainability. Low birth rate decline, as well as slow economic growth, will make sustainment of the current healthcare system difficult in the near future. An aging population will increase the amount of medical expenditure required, especially with the baby-boomer generation of those born between 1955 and 1965. Meanwhile, there is always the problem of unification for the Korean Peninsula, and what role the health insurance system will have to play when it occurs. In the presidential election, health insurance is a main issue; however, there is greater focus on expansion and expenditure than revenue. Many aspects of Korea's NHI system (1977) were modeled after the German (1883) and Japanese (1922) systems. Such systems were created during an era where infections disease control was most urgent and thus, in the current non-communicable disease (NCD) era, must be redesigned. The Korean system, which is already forty years old, must be redesigned completely. Although health insurance benefit expansion is necessary, financial measures, as well as moral hazard control measures, must also be considered. Ultimately, there are three aspects that we must consider when attempting redesign of the system. First, the health security system must be reformed. NHI and Medical Aid must be amalgamated into one system for increased effectiveness and efficiency of the system. Within the single insurer system of the NHI must be an internal market for maximum efficiency. The NHIS must be separated into regions so that regional organizers have greater responsibility over their actions. Although insurance must continue to be imposed nationally, risk-adjustment must be distributed regionally and assessed by different regional systems. Second, as a solution for the decreasing flow of insurance revenue, low premium level must be increased to an appropriate level. Likewise, the national reserve fund (No. 36, National Health Insurance Act) must be enlarged for re-unification preparation. Third, there must be revolutionary reform of benefit package. The current system built a focus on communicable diseases which is inappropriate in this NCD era. Medical benefits must not be one-time events but provide chronic disease management. Chronic care models, accountable care organization, patient-centered medical homes, and other systems that introduce various benefit packages for beneficiaries must be implemented. The reimbursement system of medical costs should be introduced to various systems for different types of care, as is the case with part C (Medicare Advantage Program) of America's Medicare system that substitutes part A and part B. Pay for performance must be expanded so that there is not only improvement in quality of care but also medical costs. Moreover, beneficiaries of the NHI system must be aware of the amount of their expenditure through a deductible payment system so that spending can be profiled and monitored. The Moon Jae-in Government has announced its plans to expand the NHI system; however, it is important that a discussion forum is created so that more accurate analysis of the NHI, its environments, and current status of health care system, can take place for reforming NHI.

NO2 and SO2 Reduction Capacities and Their Relation to Leaf Physiological and Morphological Traits in Ten Landscaping Tree Species (조경수 10개 수종에 있어 NO2, SO2 저감 능력과 잎의 생리적, 형태적 특성과의 관계)

  • Kim, Kunhyo;Jeon, Jihyeon;Yun, Chan Ju;Kim, Tae Kyung;Hong, Jeonghyun;Jeon, Gi-Seong;Kim, Hyun Seok
    • Journal of Korean Society of Forest Science
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    • v.110 no.3
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    • pp.393-405
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    • 2021
  • With increasing anthropogenic emission sources, air pollutants are emerging as a severe environmental problem worldwide. Accordingly, the importance of landscape trees is emerging as a potential solution to reduce air pollutants, especially in urban areas. This study quantified and compared NO2 and SO2 reduction abilities of ten major landscape tree species and analyzed the relationship between reduction ability and physiological and morphological characteristics. The results showed NO2 reduction per leaf area was greatest in Cornus officinalis (19.81 ± 3.84 ng cm-2 hr-1) and lowest in Pinus strobus (1.51 ± 0.81 ng cm-2 hr-1). In addition, NO2 reduction by broadleaf species (14.72 ± 1.32 ng cm-2 hr-1) was 3.1-times greater than needleleaf species (4.68 ± 1.26 ng cm-2hr-1; P < 0.001). Further, SO2 reduction per leaf area was greatest in Zelkova serrata (70.04 ± 7.74 ng cm-2 hr-1) and lowest in Pinus strobus (4.79 ± 1.02 ng cm-2 hr-1). Similarly, SO2 reduction by broadleaf species (44.21 ± 5.01 ng cm-2 hr-1) was 3.9-times greater than needleleaf species (11.47 ± 3.03 ng cm-2 hr-1; P < 0.001). Correlation analysis revealed differences in NO2 reduction was best explained by chlorophyll b content (R2 = 0.671, P = 0.003) and SO2 reduction was best described by SLA and length of margin per leaf area (R2 = 0.456, P = 0.032 and R2 = 0.437, P = 0.001, R2 = 0.872, P < 0.001, respectively). In summary, the ability of trees to reduce air pollutants was related to photosynthesis, evapotranspiration, stomatal conductance, and leaf thickness. These findings highlight effective reduction of air pollutants by landscaping trees requires comprehensively analyzing physiological and morphological species characteristics.

A Study Concerning Health Needs in Rural Korea (농촌(農村) 주민(住民)들의 의료필요도(醫療必要度)에 관(關)한 연구(硏究))

  • Lee, Sung-Kwan;Kim, Doo-Hie;Jung, Jong-Hak;Chunge, Keuk-Soo;Park, Sang-Bin;Choy, Chung-Hun;Heng, Sun-Ho;Rah, Jin-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.7 no.1
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    • pp.29-94
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    • 1974
  • Today most developed countries provide modern medical care for most of the population. The rural area is the more neglected area in the medical and health field. In public health, the philosophy is that medical care for in maintenance of health is a basic right of man; it should not be discriminated against racial, environmental or financial situations. The deficiency of the medical care system, cultural bias, economic development, and ignorance of the residents about health care brought about the shortage of medical personnel and facilities on the rural areas. Moreover, medical students and physicians have been taught less about rural health care than about urban health care. Medical care, therefore, is insufficient in terms of health care personnel/and facilities in rural areas. Under such a situation, there is growing concern about the health problems among the rural population. The findings presented in this report are useful measures of the major health problems and even more important, as a guide to planning for improved medical care systems. It is hoped that findings from this study will be useful to those responsible for improving the delivery of health service for the rural population. Objectives: -to determine the health status of the residents in the rural areas. -to assess the rural population's needs in terms of health and medical care. -to make recommendations concerning improvement in the delivery of health and medical care for the rural population. Procedures: For the sampling design, the ideal would be to sample according to the proportion of the composition age-groups. As the health problems would be different by group, the sample was divided into 10 different age-groups. If the sample were allocated by proportion of composition of each age group, some age groups would be too small to estimate the health problem. The sample size of each age-group population was 100 people/age-groups. Personal interviews were conducted by specially trained medical students. The interviews dealt at length with current health status, medical care problems, utilization of medical services, medical cost paid for medical care and attitudes toward health. In addition, more information was gained from the public health field, including environmental sanitation, maternal and child health, family planning, tuberculosis control, and dental health. The sample Sample size was one fourth of total population: 1,438 The aged 10-14 years showed the largest number of 254 and the aged under one year was the smallest number of 81. Participation in examination Examination sessions usually were held in the morning every Tuesday, Wenesday, and Thursday for 3 hours at each session at the Namchun Health station. In general, the rate of participation in medical examination was low especially in ages between 10-19 years old. The highest rate of participation among are groups was the under one year age-group by 100 percent. The lowest use rate as low as 3% of those in the age-groups 10-19 years who are attending junior and senior high school in Taegu city so the time was not convenient for them to recieve examinations. Among the over 20 years old group, the rate of participation of female was higher than that of males. The results are as follows: A. Publie health problems Population: The number of pre-school age group who required child health was 724, among them infants numbered 96. Number of eligible women aged 15-44 years was 1,279, and women with husband who need maternal health numbered 700. The age-group of 65 years or older was 201 needed more health care and 65 of them had disabilities. (Table 2). Environmental sanitation: Seventy-nine percent of the residents relied upon well water as a primary source of dringking water. Ninety-three percent of the drinking water supply was rated as unfited quality for drinking. More than 90% of latrines were unhygienic, in structure design and sanitation (Table 15). Maternal and child health: Maternal health Average number of pregnancies of eligible women was 4 times. There was almost no pre- and post-natal care. Pregnancy wastage Still births was 33 per 1,000 live births. Spontaneous abortion was 156 per 1,000 live births. Induced abortion was 137 per 1,000 live births. Delivery condition More than 90 percent of deliveries were conducted at home. Attendants at last delivery were laymen by 76% and delivery without attendants was 14%. The rate of non-sterilized scissors as an instrument used to cut the umbilical cord was as high as 54% and of sickles was 14%. The rate of difficult delivery counted for 3%. Maternal death rate estimates about 35 per 10,000 live births. Child health Consultation rate for child health was almost non existant. In general, vaccination rate of children was low; vaccination rates for children aged 0-5 years with BCG and small pox were 34 and 28 percent respectively. The rate of vaccination with DPT and Polio were 23 and 25% respectively but the rate of the complete three injections were as low as 5 and 3% respectively. The number of dead children was 280 per 1,000 living children. Infants death rate was 45 per 1,000 live births (Table 16), Family planning: Approval rate of married women for family planning was as high as 86%. The rate of experiences of contraception in the past was 51%. The current rate of contraception was 37%. Willingness to use contraception in the future was as high as 86% (Table 17). Tuberculosis control: Number of registration patients at the health center currently was 25. The number indicates one eighth of estimate number of tuberculosis in the area. Number of discharged cases in the past accounted for 79 which showed 50% of active cases when discharged time. Rate of complete treatment among reasons of discharge in the past as low as 28%. There needs to be a follow up observation of the discharged cases (Table 18). Dental problems: More than 50% of the total population have at least one or more dental problems. (Table 19) B. Medical care problems Incidence rate: 1. In one month Incidence rate of medical care problems during one month was 19.6 percent. Among these health problems which required rest at home were 11.8 percent. The estimated number of patients in the total population is 1,206. The health problems reported most frequently in interviews during one month are: GI trouble, respiratory disease, neuralgia, skin disease, and communicable disease-in that order, The rate of health problems by age groups was highest in the 1-4 age group and in the 60 years or over age group, the lowest rate was the 10-14 year age group. In general, 0-29 year age group except the 1-4 year age group was low incidence rate. After 30 years old the rate of health problems increases gradually with aging. Eighty-three percent of health problems that occured during one month were solved by primary medical care procedures. Seventeen percent of health problems needed secondary care. Days rested at home because of illness during one month were 0.7 days per interviewee and 8days per patient and it accounts for 2,161 days for the total productive population in the area. (Table 20) 2. In a year The incidence rate of medical care problems during a year was 74.8%, among them health problems which required rest at home was 37 percent. Estimated number of patients in the total population during a year was 4,600. The health problems that occured most frequently among the interviewees during a year were: Cold (30%), GI trouble (18), respiratory disease (11), anemia (10), diarrhea (10), neuralgia (10), parasite disease (9), ENT (7), skin (7), headache (7), trauma (4), communicable disease (3), and circulatory disease (3) -in that order. The rate of health problems by age groups was highest in the infants group, thereafter the rate decreased gradually until the age 15-19 year age group which showed the lowest, and then the rate increased gradually with aging. Eighty-seven percent of health problems during a year were solved by primary medical care. Thirteen percent of them needed secondary medical care procedures. Days rested at home because of illness during a year were 16 days per interviewee and 44 days per patient and it accounted for 57,335 days lost among productive age group in the area (Table 21). Among those given medical examination, the conditions observed most frequently were respiratory disease, GI trouble, parasite disease, neuralgia, skin disease, trauma, tuberculosis, anemia, chronic obstructive lung disease, eye disorders-in that order (Table 22). The main health problems required secondary medical care are as fellows: (previous page). Utilization of medical care (treatment) The rate of treatment by various medical facilities for all health problems during one month was 73 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 52% while the rate of those who have health problems which did not required rest was 61 percent (Table 23). The rate of receiving of medical care for all health problems during a year was 67 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 82 percent while the rate of those who have health problems which did not required rest was as low as 53 percent (Table 24). Types of medical facilitied used were as follows: Hospital and clinics: 32-35% Herb clinics: 9-10% Drugstore: 53-58% Hospitalization Rate of hospitalization was 1.7% and the estimate number of hospitalizations among the total population during a year will be 107 persons (Table 25). Medical cost: Average medical cost per person during one month and a year were 171 and 2,800 won respectively. Average medical cost per patient during one month and a year were 1,109 and 3,740 won respectively. Average cost per household during a year was 15,800 won (Table 26, 27). Solution measures for health and medical care problems in rural area: A. Health problems which could be solved by paramedical workers such as nurses, midwives and aid nurses etc. are as follows: 1. Improvement of environmental sanitation 2. MCH except medical care problems 3. Family planning except surgical intervention 4. Tuberculosis control except diagnosis and prescription 5. Dental care except operational intervention 6. Health education for residents for improvement of utilization of medical facilities and early diagnosis etc. B. Medical care problems 1. Eighty-five percent of health problems could be solved by primary care procedures by general practitioners. 2. Fifteen percent of health problems need secondary medical procedures by a specialist. C. Medical cost Concidering the economic situation in rural area the amount of 2,062 won per residents during a year will be burdensome, so financial assistance is needed gorvernment to solve health and medical care problems for rural people.

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