• Title/Summary/Keyword: 1982

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A Prediction Model for Forecast of the Onset Date of Changmas (장마 시작일 예측 모델)

  • Lee, Hyoun-Young;Lee, Seung-Ho
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.112-122
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    • 1993
  • Since more than 50${\%}$ of annual precipitation in Korea falls during Changma, the rainy season of early summer, and Late Changma, the rainy season of late summer, forcasting the onset days Changmas, and the amount related rainfalls would be necessary not only for agriculture but also for flood-control. In this study the authors attempted to build a prediction model for the forecast of the onset date of Changmas. The onset data of each Changma was derived out of daily rainfall data of 47 stations for 30 years(1961~1990) and weather maps over East Asia. Each station represent any of the 47 districts of local forecast under the Korea Meteorological Administration. The average onset dates of Changma during the period was from 21 through 26 June. The dates show a tendency to be delayed in El Ni${\~{n}}o years while they come earlier than the average in La Nina years. In 1982, the year of El Ni${\~{n}}o, the date was 9 Julu, two weeks late compared with the average. The relation of sea surface temperature(SST) over Pacific and Northern hemispheric 500mb height to the Changma onset dates was analyzed for the prediction model by polynomial regression. The onset date of Changma over Korea was correlated with SST in May(SST${_(5)}{^\circ}$C) of the district (8${^\circ}$~12${^\circ}S, 136${^\circ}~148${^\circ}W)of equatirial middle Pacific and the 500mb height in March (MB${_(3)}$"\;"m)over the district of the notrhern Hudson Bay. The relation between this two elements can be expressed by the regression: Onset=5.888SST${_5}"\;"+"\;"0.047MB${_(3)}$"\;"-251.241. This equation explains 77${\%}$ of variances at the 0.01${\%}$ singificance level. The onset dates of Late Changma come in accordance with the degeneration of the Subtro-pical High over northern Pacific. They were 18 August in average for the period showing positive correlation(r=0.71) with SST in May(SST)${_(i5)}{^\circ}$C) over district of IndiaN Ocean near west coast of Australia (24${^\circ}$~32${^\circ}$S, 104${^\circ}$~112${^\circ}$E), but negativ e with SST in May(SST${_(p5)}{^\circ}$ over district (12${^\circ}$~20${^\circ}$S,"\;"136${^\circ}$~148${^\circ}$W)of equatorial mid Pacific (r=-0.70) and with the 500mb height over district of northwestern Siberia (r=-0.62). The prediction model for Late Changma can be expressed by the regression: Onset=706.314-0.080 MB-3.972SST${_(p5)}+3.896 SST${_(i5)}, which explains 64${\%}$ of variances at the 0.01${\%}$ singificance level.

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A Study on the Administration for the Han River Water Quality Control (漢江 水質保全 行政에 관한 硏究)

  • Kim, Kwang Hyop
    • Journal of Environmental Health Sciences
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    • v.10 no.2
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    • pp.9-40
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    • 1984
  • This thesis purports to overview the diverse administrative and organizational factors and plannings developed by the government organizations, municipal or otherwise, to tackle the Han River water pollution issues in the past years. This thesis also looks into the ever-worsening Han River water pollution problems, in particular, in terms of the various government plans ostensibly designed to reduce the pollution level but with little success. Also dealt with are the efficiencies with which the laws and decrees on water pollution the administrative organizations put to use in the prosecution of the diverse antiwater pollution projects involving the Han River basin. From the early 1960's up to the 1970's the government had concentrated on the growth-oriented economic policy with the result that little attention had been paid to the water pollution and other environmental issues that are bound to arise from the massive economic growth. Belatedly, the five-year Hah River Development Project was initiated in 1982 with emphasis on reducing the water pollution level at Hah River to the minimum. The following are the gists of the thesis and recommendations for the future antiwater pollution plans by the administrative organizations: 1. Documents to date indicate that the irrigation projects along the Han River area had been the main focus of attention during the Yi Dynasty and under the Japanese rule of the country. 2. Despite that the water pollution issue became the subject of many debates among the academic and research institutions in the 1960's and in the 1970's, the administrative organizations in charge of the Han River water quality control failed to come up with a concrete plan for the river's water quality control. 3. Nevertheless, the water pollution of the Han River area in fact began in the 1950's, with the unprecedented concentration into Seoul of population and the industrial facilities on a larger scale, in particular, enforced by the government's strong growthoriented policy in its Economic Development plans in the 1960's. 4. Starting in the 1960's, the Han River water pollution level dramatically increased, but the government was reluctant to promulgate or put into effect strong measures to curb the many factors contributing to the river water pollution, thus worsening the environmental issues along the Han River basin. 5. The environmental protection law and other laws and decrees relating to the antiwater and air pollution issues that were subsequently put into effect underwent so many changes that efficient anti-water pollution policies could not be effected for the Han River basin. The frequent organizational reshuffle within the administrative units concerned with environmental problems has resulted in the undue waste in personnel management and finance. 6. The administration on the environmental protection could not be efficiently carried out due to the organizational overlapping. Under the existing law, frequent organizational frictions and inefficiency are bound to occur among the central government offices themselves, as well as between the central government and the Seoul city administration, and among the city's administrative offices over the conservation of the Han River basin and over the river's anti-water pollution issue. 7. In the planning and prosecution of the Han River project, political influences from the president down to the lower-level politicious appear to have been involved. These political influences in the past had certainly had negative influence on the project, nevertheless, it appears that in the recent years, these political influences are not all that negative in view of the fact that they serve as a positive contributing factor in developing a better water quality control project along the Han River basin. The following are a few recommendations based on the data from the thesis: First, officials in charge of the Han River water quality control should pay attention to a careful screening of the opinions and recommendations from the academic circles and from the public should be made so that the government could better grasp the core issues in the environmental problems that require preventive and other necessary measures. Second, vigorous redistribution policies of population and industrial facilities away from the Seoul area should be pursued. Third, the government should refrain from revising or revamping too frequently the laws and decrees on the anti-water pollution, which is feared to cause undue inconveniences in the environmental administration. Fourth, a large-scale streamlining should be made to the existing administrative organization in an effort to do away with the inter- and intra-organizational friction. It is recommended that a secretariat for the Hah River basis conservation be established. Fifth, High-level administrative officials, with a thorough knowledge and vision on the Han River water quality control, should be prepared to better deal with the budgeting and personnel management for the Han River water pollution control not only at the control government, but also at the Seoul city municipal government levels. Environmental issues should be kept distinct from political issues. Environmental issues should not serve as a window-dressing for sheer political purposes. Sixth, the Hah River proiect should also include, along with the main Han River basin, those areas covering North Han River, South Han River, and the tributaries to the main river basin. The 'Han River Basin Water Quality Control Board' should be established immediately as a means of strengthening the current Han River basin water quality control policy. Seventh, in drawing up the Han River proiect, the administrative officials should be aware that Han River basin is a life line for those people in the region, providing them with not only a sheer physical space, but with a psychological living space for their everyday life.

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Erosion Control Effect by Soil ansi Vegetation Transition in Mountainous Area after Soil Erosion Measures were Initiated (토양 및 식생변화에 따른 토지 사방 공사의 효과에 관한 연구)

  • 이천용
    • Journal of the Korean Institute of Landscape Architecture
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    • v.14 no.2
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    • pp.7-16
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    • 1986
  • This study was carried out to investigate the effects of such erosion control measures as sowing, planting and small earth structures on the soil and vegetation. In order to study the changes in soil and vegetation, 36 plots were surveyed from 1981 to 1982 in the large erosion control area which is restored last 20 years. The factors which were measured included vegetation coverage, tree growth, number of species, soil depth, soil consistancy, and Chemical properties of soil. The results were as follows; 1) Maximum coverage of the overstory and understory was attained 7 years after the initiation of erosion control. So the overstory need to be tended and pruned. 2) Diversity of species increased until age 6 after which it began to decrease. 3) In order of tree growth, black locust was the fastest, followed by siberian alder and pitch pine. The initial growth of black locust, though the best among the 3 tree stop., decreased rapidly year by year. At the same time, siberian alder and pitch pine grew well until 12 and 6 years after the initiation of erosion control respectively. 4) Fifty percent of the initially planted trees died within 8 yeard. The mortality of siberian alder occurred until the 20th year while the mortality of pitch pine stopped after 10 years. Thereafter 500 trees per hectare were maintained. 5) The soil depth in A and B horision increased by 2cm annually during 20 years. The soil consistency also decreased rapidly until 7th year. The physical soil properties of the rehabilitated areas were improved after the 14th year. 6) The soil pH tend to decrease from 5.3 during the first year to 5.1 during the twentieth year. 7) The organic matter and nitrogen content in the soil were increased by fertilization but after 20 years these nutrients are still deficient for normal tree growth. 8) The phosphorous content in the soil was high in the first year but the longer the period after the initiation of erosion control the lese the content of phosphorous. 9) The biomass of black locust was the highest and increased continuously. The biomass of siberian alder on the contrary decreased from the 15th year because the number of trees in this place was very low. The total biomass in the twentieth year after erosion control initiation was 105.7 ton per hectare.

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Variation of Rice Production for Two Decades before and after Breeding Tongil Variety in Korea (수도 통일품종 육성보급 전후 20년간의 생산성 변이)

  • Eun-Woong Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.3
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    • pp.183-192
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    • 1982
  • The variability of rice productivity during last 2 decades (1961-1980) of ten years before and after the introduction of"Tongil" was reviewed from the epochal, regional and varietal points of view. During that period the cultivated area of paddy rice have remained almost unchanged, while the total rice production have got elevated from 3, 463 million metric tons in 1961 to 6.006 million metric tons in 1977, recording 73.4% increase. This remarkable increase in rice production is considered to be attributable much to the development and release of new high yielding variety, "Tongil", coupled with the amelioration of cultural techniques. However, in 1978 Tongil type varieties experienced the epidemic outbreak of blast disease due to the shifted race population of blast fungus and in 1980 recorded poor rice production as low as in 1960's due to the unfavorable weather stress throughout the rice growing season, giving rise to many problems awaiting solutions for securing the stabilized high production of rice. The rice yield has continued the gradual increase during last two decades but its difference between farmer and research organization have got wider from 79kg/10a during 1960 to 1971 to 101kg/l0a during 1972 to 1980, and also the inter-regional differences have been increased from 50-60kg/10a to 80kg/10a during those periods. Therefore, this proves that we have raised the upper boundary of rice yield by increasing the yield potential of rice variety but have not changed those absolute deviations. Estimates indicate that the increased rice production during that period was indebted 40 percent to the varietal improvement and 13 percent to the ameliorated agro-technologies, and the rest, 47 percent, could be ascribed to the other factors besides varieties and cultural technologies such as the improved agricultural environments, etc. Of course, even though it cannot be expected to unify the cultural environments and the cultural technologies, provided that much efforts are to be endeavored to minimize the yield difference of 20 percent between farmer and research organizations and the inter-regional yield difference of 20 percent, much increased rice production can be expected to be achieved with the current level of cultural technology and the yielding potential of the present rice varieties. In order to expedite the above effects on rice production the followings are to be put into practices consitently and steadfastly. 1. Reinforcement of breeding for varieties with high yielding potential and less susceptible to climatic-stress and pests, and of basic physicoecological studies of rice plant for improving the cultural technologies. 2. Continuous endeavor to secure the stabilized cultural environments by improving the soil fertility and increasing the drainage and irrigation facilities. 3. Political back-up to encourage the farmers' incentives for production 4. Precise surveys for agricultural statistics to facilitate the long-term planninge long-term planning.

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Investigational Studies on Reproductive Failures of Slaughtered Cows (도살빈우의 번식장애사례 조사연구)

  • 이용빈;임경순
    • Korean Journal of Animal Reproduction
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    • v.6 no.1
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    • pp.19-30
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    • 1982
  • 1. The cows slaughtered at age of 3, 4, 6, 7, 8, and 9 years old were 1.5, 1.5, 15.0, 62.5 and 4.4% respectively. 2. The cows slaughtered at 351-450kg and more than 500kg were 60 and 28% respectively. 3. Best, very good, good and bad cows in nutritional condition were 1.6, 25.8, 62.9, and 9.7% respectively. Among the six cows which were bad nutrition, the two were with severe endometritis, the three were normal in genital function and one was on 70 days of pregnancy. 4. Holstein cows(55.2%) showed higher reproductive failure than the Korean cows(33.3%). 5. The slaughted ratio of the Korean cattle and Holstein cows was 36 and 64% respectively. 6. Pregnant cows were about 16% among the slaughtered one. 7. Reproductive failures were composed of 46% in uterus, 32% in ovaries, 8% in udder, 6% in oviduct, 4% in cervix of uterine, 2% in vagina and 2% inmummified fetus. 8. Forty six percentages of uterine diseases were as follows; horn, 13%, body of uterus, 32% and ovary diseases were 32%, that is, 12% of ovary atrophy, 8% of ovarycyst and 6% of lutealcyst. 9. The cows of reproductive failures were commonly infected with 1.6 kinds of diseases. 10. According to classification, six type of ovaries were as follows; normal, 58%, ovary-cyst, 11%, luteum cyst, 4%, coexistence of follicles and corpus luteum, 16%, weak function of ovaries, 10% and ovarian atrophy, 1%. 11. Major axis, minor axis and thickness of right ovary were larger than those of left one both in Korean cattle and Holstein cows. Holstein cow had generally larger size of ovary than these of the Korean cattle.. 12. The left and right oviducts showed no difference in length, but Holstein had longer oviduct than Korean cow. 13. There was no difference in the length of uterine horn between right and left in the Korean cows, but the right was longer than the left in Holstein cows. 14. Holstein had longer horn and body of uterine than the Korean cows. 15. The weight of right ovary was heavier than that of left in both breeds, but there was no differences in weight of left ovary between two breeds and right ovary of Holstein breed was heavier than that of the Korean cow. 16. The weight of right oviduct and uterine born was heavier than that of the left, and Holstein had heavier oviducts and uterine horns than the Korean cows. 17. Holstein had heavier uterine body and cervix of uterine than the Korean cows. 18. The length of reproductive systems of Korean cow is as follows; Major and minor diameter and thickness ofovary are 3.6${\pm}$0.7, 2.3${\pm}$0.4 and 1.6${\pm}$1.4 cm in left and 3.7${\pm}$0.6, 2.5${\pm}$0.5 and 1.8${\pm}$0.5 cm in right. Oviduct is 28.4${\pm}$3.1 cm in left and 27.8${\pm}$3.3 cm in right. Uterine horn is 27.4${\pm}$4.5 cm in left and 27.7${\pm}$4.9 cm in right. Uterine body and cervix are 3.4${\pm}$1.1 and 6.5${\pm}$1.7 cm. 19. The length of female reproductive systems ofHolstein cow is as follows; Major and minor diameter and thickness of ovary are 3.9${\pm}$1.3, 2.3${\pm}$0.5, and 1.5${\pm}$0.6 cm in left and 4.0${\pm}$0.8, 2.8${\pm}$0.6 and 1.8${\pm}$0.6 cm in right. Oviduct is 29.4${\pm}$4.2 cm in left and 29.3${\pm}$4.1 cm in right. Uterine horn is 30.2${\pm}$7.4 cm in left and 32.6${\pm}$8.4 cm in right. Uterine body and cervix are 4.5${\pm}$2.5 and 7.8${\pm}$2.9 cm. 20. The weight of reproductive systems of Korean cow is as follows; Ovary is 8.4${\pm}$4.1 g in left and 9.3${\pm}$3.6g in right. Oviduct is 1.5${\pm}$0.5 g in left and 1.6${\pm}$0.5 g in right. Uterine horn is 109${\pm}$27 g left and 118${\pm}$32 g in right. Uterine body and cervix are 30.4${\pm}$14.1 and 76.7${\pm}$38.4g. 21. The weight of reproductive systems of Holstein cow is as follows; Ovary is 8.2${\pm}$3.1 g in left and 12.5${\pm}$5.6 g in right. Oviduct is 1.7${\pm}$0.6 g in left and 1.9${\pm}$0.9 g in right. Uterine horn is 199${\pm}$14.2 g in left and 221${\pm}$111.2g in right. Uterine body and cervix are 58.2${\pm}$46.5 and 126.7${\pm}$103.3 g.

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Estimation of Genetic Parameters for Economic Traits and Profit by Milk Production of Holstein Dairy Cattle in Korea (국내 Holstein종 젖소의 경제형질과 착유량에 따른 소득의 유전모수 추정)

  • Noh, Jae-Kwang;Choi, Yun-Ho;Cho, Kwang-Hyun;Choi, Tae-Jeong;Na, Seung-Hwan;Cho, Ju-Hyun;Kim, Jin-Hyung;Shin, Ji-Sub;Do, Chang-Hee
    • Journal of Animal Science and Technology
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    • v.54 no.4
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    • pp.275-282
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    • 2012
  • The data including milk yields, fat and protein percent for 628,395 heads collected by National Agricultural Cooperative Federation, 15 type traits and final score for 62,262 heads collected by Korea Animal Improvement Association, which were born in 1998 to 2004, and net profits calculated from milk price and raising expenses of individuals were used to estimate genetic parameters. The highest positive genetic correlation, 0.81, was shown between body depth (BD) and loin strength (SR). Genetic correlations between body depth (BD) and udder depth (UD), front teat placement (TP) and front teat length (TL) were -0.23, which were lowest among the linear type traits. Furthermore, medium level of negative genetic correlations were shown the milk yield with milk contents rate traits. Mostly low level of positive genetic correlations were shown between the milk traits and linear score traits except milk yield and stature. Most of the genetic correlations of between the linear score traits and net profit were low level of positive or negative genetic correlations. Among the genetic correlations, body depth (BD), angularity (DF) and rear attachment width (UW), and final score (FS) with net profit were high as 0.17, 0.17, 0.18 and 0.18, respectively. Finally all of the genetic correlations between net profit and milk traits were positive and higher than the linear traits with positive genetic correlations. The results of this study suggest that net profit has been related with the linear traits, such as body depth (BD), angularity (DF) and rear attachment width (UW) traits, and furthermore, milk traits including yield and contents rates influence positively and greatly on net profit.

A Clinical Study on the Surgical Treatment of the Rheumatic Cardiac Valve Disease (류마티스성 심장판막질환의 외과적 치료에 대한 임상적 연구)

  • 김종원;정황규;이성광;김병준;신영우
    • Journal of Chest Surgery
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    • v.31 no.4
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    • pp.346-352
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    • 1998
  • Rheumatic valvulitis produces at least three distinct pathologic changes, the degree varying widely among the patients: fusion of the valve leaflets at the commissures; fusion and shortening of chordae tendinae: and fibrosis of the leaflets with subsequent stiffening, contraction and calcification. The most extensive changes usually are seen in patients with recurrent attacks of rheumatic fever. We studied on outcome of the surgical treatments of rheumatic valvular diseases that have been experienced for 12 years since 1982 at Pusan National University Hospital. The diagnoses were made by rheumatic fever history, echocardiographic findings, gross operative findings and microscopic findings. Total 502 patients were performed surgery for valvular heart diseases and 440 patients of rheumatic origin have bene analysed. There were more female than male patients as 1.3:1, and the mean age was 37.8 years old. 96.3% of them affected to the mitral valve, 19.8% to aortic valve, 16.3% affected to the tricuspid valve. Most of them underwent valve replacement, and valve repair was done in 3.9% of patients. There were 36 hospital deaths(8.2%) mainly from low cardiac output syndrome, and 15 late deaths equally due to embolism and hemorrhage. Follow up was 90.1% completed(2890 patient- year). Linealized rates of late complication events are follows : thromboembolism 1.3% per patient year; anticoagulant related hemorrhage 0.8% per patient year. Overall actuarial survival including hospital mortality was 92.7+/-2.9% in 1 year, 88.0+/-4.5% in 5 year, 82.3+/-7.7% in 10 year. We conclude that the rheumatic disease is still the most frequent and the most important cause of heart valve disease. So more intensive study is needed in spite of the abrupt decreasing rate of rheumatic fever in U.S.A. and other industrial country.

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Studies on the Constituents and Culture of the Higher Fungi of Korea(II) -The Antitumor Components and Culture of Lentinus edodes(Berk.) Singer- (한국산(韓國産) 고등균류(高等菌類)의 성분(成分) 및 배양(培養)에 관한 연구(硏究)(II) -표고버섯의 항암성분(抗癌成分) 및 배양(培養)-)

  • Chung, Kyeong-Soo
    • The Korean Journal of Mycology
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    • v.10 no.1
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    • pp.33-39
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    • 1982
  • Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.

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Assessment of the Activities of General Physicians in Health Subcenters and a Scheme to Improve the Training Program (보건지소 공중보건 일반의사의 업무수행정도와 수련개선방안)

  • Park, Jung-Han;Chun, Byung-Yeol;Woo, Kuck-Hyeun
    • Journal of Preventive Medicine and Public Health
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    • v.19 no.2 s.20
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    • pp.193-202
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    • 1986
  • The activities of general physicians (GPs) in health subcenters and their competency for clinical skills were assessed to develop a scheme to improve the training program. One hundred-twenty GPs in southern four provinces (Kyungpook, Kyungnam, Chunpook, Chunnam) were randomly selected and 97 were interviewed between January 9 and February 10, 1984. Of the 97 GPs, 86 provided all the information we requested. Average number of patient visits per health subcenter in a day was 30-40 in the demonstration project area for the class II medical insurance whereas it was 3-4 visits in other area. The interviewees were asked to rate their competency in 63 clinical skills. The skills in which over 50% of the interviewees rated themselves competent were only 12 items including IM injection, IV injection, wound dressing, etc. Less than 10% of the interviewees rated themselves competent in such skills as maternal health care, emergency medical care, preventive and promotive health services. Most part of the training program of the NIH for the GPs were not applicable to their field work as the training contents were unrealistic. Clinical training at a local general hospital was of great help in 38.8% and the rest of training was not much helpful as the training was inadequate due to lack of trainer or indifference of the trainer. For more effective training of the GPs, the training program of the NIH should be modified to be more realistic and utilize competent field workers as the instructors. It may be more effective if the training is carried out at several local centers. Ideal length of the clinical training for the GPs is 4 months. A pocketbook should be developed that includes specific skills to master during the clinical training and require the trainer to confirm the achievement. The Ministry of Health and Social Affairs should provide the training hospitals with a training guideline and evaluate the training activities and make sure that the training hospital has specialist for each of the 4 major clinical departments. The Ministry of Health and Social Affairs should provide the GPs with a continuing education to assist the problem solving in the field and motivate them to actively carry out the health program. A province may be divided into several regions and a supervisory committee may be organized with specialists in each region. The committee may hold a meeting for the GPs periodically and respond to the specific questions of the GPs by mail.

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Some Characteristics of Teflon-Thermoluminescent Dosimeters (테프론 열형광선량계(熱螢光線量計)의 특성(特性))

  • Lee, Soo-Yong
    • Journal of Radiation Protection and Research
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    • v.7 no.1
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    • pp.23-33
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    • 1982
  • The characteristic thermoluminescence responses of Teflon thermoluminescent dosimeters to radiations have been studied by the variation of radiation qualities as well as the high dose radiations. The change in the sensitivity of TLDs for different radiation qualities were studied through not only the photon energy dependence but also the change of supralinearity on the photon energy dependence, by exposing $^{60}Co$ gamma rays, the effective X-rays of 44keV, 69keV, 108keV, and thermal neutron of 0.04 eV. The results were as the following: The TL response of $T-CaSO_4$: Dy as a function of absorbed dose was linear up to about 5 Gy, and the response beyond 5Gy was supralinear for $^{60}Co$ gamma rays. The supralinearity of T-LiF-7 became noticeably apparent more than that of $T-CaSO_4$:Dy and also the lower the LET of radiation became the higher the supralinear effects were. No supralinearity appeared for the thermal neutron irradiations equivalent to 10Gy of $^{60}Co$ gamma rays. The relative sensitivities (Rs), which depended on the doses of $^{60}Co$ gamma rays to the TLDs of T-LiF-7 and T-$CaSO_4$:Dy could be, respectively, approximated to the following empirical formula fitted by the least square method: $$R_{LiF}=1.021-0.04581\;logD+0.402(logD)^2-0.405(logD)^3,\;\;5{\times}10^3{\geq}D{\geq}1(Gy)$$ $$R_{CaSO_4}=0.976-0.3241\;logD+0.262(logD)^2-0.298(logD)^3,\;5{\times}10^3{\geq}D{\geq}1(Gy)$$.

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