• Title/Summary/Keyword: 1990′s

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Studies on Engneering Properties of Coal Ash Obtained as Industrial Wastes (산업폐기물(産業廢棄物)로 발생(發生)되는 석탄회(石炭灰)의 토질력학적(土質力學的) 특성(特性)에 관한 연구(硏究))

  • Chun, Byung Sik;Koh, Yong Il;Oh, Min Yeoul;Kwon, Hyung Seok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.1
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    • pp.115-123
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    • 1990
  • The purpose of this study was to examine the uses of coal ash as a type of construction material. The methods of examination were chemical anlysis, soil laboratory test and the soil vibration test. Materials used were coal ash obtained as a by-product from 5 thermal power plants in Yongdong, Yongwol, Sochon(anthracite coal) and in Samchonpo and Honam (bituminous coal). Over 70% of the coal ash consisted of silica and alumina. The fly ash grain size showed a uniform distribution from fine-sand to silt, and that of the bottom ash showed from sand to gravel. The specific gravity and density of the coal ash were low. The long term strength increased gradually due to the self-setting property resulting from pozzolanic activity. The shear strength was higher than that of general soil. Cohesion and optimum moisture content of anthracite coal ash were higher than bituminous coal ash, whereas the maximum dry density was higher in bituminous coal ash. The coal ash dynamic Young's modulous curve range was similar to that of general soil. Of the results from the soil vibration test by car-running, the size relative acceleration level in the ash pond was higher than that of natural ground, but the damping ratio was lower than that of natural ground near the ash pond. The coal ash has more advantageous engineering properties than general soil with particles of the same size. For example, the California Bearing Ratio of the bottom ash at both Yongdong and Yongwol was 77~137%. Therefore we expect that if further study is done, coal ash can be used as a construction material when reclaiming seashore, construction embankments, road construction, making right-weight aggregate, or as a general construction material.

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Cell-mediated immunity in mice infected with Acanthumoeba culbertsoni (Acanthamoeba culbertsoni 감염에 있어서 세포 매개성 면역)

  • Kim, Myeong-Jun;Sin, Ju-Ok;Im, Gyeong-Il
    • Parasites, Hosts and Diseases
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    • v.28 no.3
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    • pp.143-154
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    • 1990
  • Observations were made on the differences of cell-mediated responses in mice of three infectiorl groups di여erently scheduled in their severity with pathogenic Acanthamoeba culbertseni. Infections were done by dropping $5{\;}{\mu}l$ saline suspension containing $3{\times}10^3,{\;}1{\times}10^4,{\;}or{\;}1{\times}10^5$ trophosoites, respectively. Amoebae were cultured anenically in CGV medium and inoculated into the right nasal cavity of CSH/HeJ mice aging around 6∼8 weeks, under the anesthesia by intraperitoneal injection of secobarbital. Delayed type hypersensitivity (DTH) responses in footpad and blastogenlc responses of mouse spleen cells using ($^3H$)-thymidine and the serum antibody titer were measured up to day 14 after infection, and natural killer cell activities were measured up to day, i after infection. The results obtained in this study were as follows: 1. The mice infected with $3{\times}10^3$ trophosoites showed mortality rate of 17%, and 345 in the mice infected with $1{\times}10^4$ trophozoites and 65% with $1{\times}10^5$ trophozoites. 2. In regard to DTH responses in all experimental groups, the level increased on day 7 and declined on day 14 after infection, but their differences could not be noted between infected and control groups. 3. The blastogenic responses of splenocytes treated with amoeba Iysates and lipopolysaccharides (LPS) showed no difference from the control group. The blastogenic responses of splenocytes treated with concanavalin A were declined significantly in the experimental group as compared with the control group, but the blastogenic responses of splenocytes treated with polyinosinic acid were not different from the control group. There was also no difference among three infected groups. 4. The cytotoxic activity of the natural killer cells was activated on day 1 after infection and declined to the level of control group on day 2 in all experimental groups. On day 5 after infection, the natural killer cell cytotoxicity was significantly suppressed as compared with the control groups. 5. The serum antibody titers of the infected mice increased after day 7, but there was no statistical difference between the three infected groups. In summary of the results, there was no difference in cell-mediated immune responses of three experimental groups scheduled with different infection intensities. But there was a significant difference in cell$.$mediated immune responses between infected and control mice. It is considered that cell-mediated immune responses should be involved in murine model infected with A. culbertsoni.

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Studies on Decision of Suitable Housing Density in Caged Laying Hens (케이지 산란계의 적정 사육밀도 구명에 관한 연구)

  • 김종문;이덕수;정선부;오세정
    • Korean Journal of Poultry Science
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    • v.17 no.4
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    • pp.318-326
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    • 1990
  • This experiment was conducted to determine the economic housing density levels on caged laying hens The experiment was carried out with 600 ISA Babcock strain of white coder and 450 ISA Brown strain of brown color for production period(21-72 weeks) from May 11. 1987 to June 27. 1988. The levels of housing density was employed 5 or 6 by hen's color from 272 to 920$\textrm{cm}^2$/per hen. The results obtained were summarzed as follows : 1. Although there were not statistically significant among the housing density levels, The body weight gain for pullet period(14-20 weeks) were in case of white pullet the lowest at the group of high crowding density (272$\textrm{cm}^2$/per pullet) and in case of Brown pullet was the lowest at the group of high crowding density(306$\textrm{cm}^2$/per pullet). 2. Viabillity of pullet from 14 to 20 weeks were more 97% and there urere not statistically significant among the housing density. 3. Viabillity of laying hens was increased as increasing housing density through the etire product period(21-72 weeks) but 453$\textrm{cm}^2$/per hen group(in case of brown hen) showed a significant difference (P<.05). 4. Rate of egg production through the etire production period(21-72 weeks) were significantly increased by increasing housing density (P<.05 or .01). 5. Average egg weight through the entire production period(21-72 weeks) was not significantly different among housing density levels at all laying kent 6. In case of white strain, egg mass per hen among treatment during the age of 63-72 weeks were decreased by increasing housing density, meanwhile, in case of brown strain were increased by decreasing housing density during the whole period and there were significant different among the all treatment 7. There were no significant different in feed intake among the all treatment through the entire production period(21-72 weeks) at the white strain laying hens but in case of brown strains, Feed intake were increased by increasing housing density and feeding spece/per hen, and there were significant different among the all treatment 8. Feed requirements per egg at white strain was the highest when the 272$\textrm{cm}^2$/per hen levels and at the brown strains was the highest when the 306$\textrm{cm}^2$/per hen levels, however, among the other treatment were no significant.

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KOREAN CHILD AND ADOLESCENT PSYCHIATRY - A REVIEW OF THE PAST, THE PRESENT AND THE FUTURE - (한국 소아 ${\cdot}$ 청소년정신의학 - 과거 ${\cdot}$ 현재 ${\cdot}$ 미래 -)

  • Hong, Kang-E
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.14 no.2
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    • pp.139-149
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    • 2003
  • Objectives:To review the history of the development and current status of Korean Child and Adolescent Psychiatry and to propose the future tasks at this 20th anniversary of Korean Academy of Child and Adolescent Psychiatry. Methods:Records and publications of Korean Academy, personal communications with senior members of the Academy, the author's recollections and memoirs. Results:Korean Child Psychiatry started with opening Child Psychiatry Clinic at Seoul National University Hospital in 1979 and establishing Division of Child and Adolescent Psychiatry at the same hospital in 1980. A Child Psychiatry Study Group was formed in 1983 and it transformed into Korean Academy of Child and Adolescent Psychiatry in 1986. In the past 20 years, Korean child and adolescent psychiatry made an impressive progress and contributed significantly to the development of Korean medicine as well as to the establishment of child mental health service. There are 77 board-certified and 48 board-eligible child psychiatrists, and 18 child psychiatry fellows are in training as of 2003. Main forces of this successful introduction of child psychiatry are 1) 7 child psychiatry training centers at major university hospitals, 2) publication of Korean Journal of Child and Adolescent Psychiatry in 1990, 3) the establishment child psychiatry board certification system in 1996. Korean child psychiatry has extended its role in the international child psychiatry and took leadership in establishing Asian Society of Child and Adolescent Psychiatry and Allied Professions(ASCAPAP). Conclusion:Korean child psychiatry has achieved a remarkable progress for the past 20 years and is currently producing 15 or more child psychiatry each year. However, there are needs of more active involvements in adolescent problems, more active consultation-liaison services at general hospitals as well as community mental health institutions. More school consultation and preventive educational services are desired. There is a urgent need of carrying out more empirical studies with strong scientific rigor. Korean Academy should pay attention and provide assistance to the development of child psychiatry service in other countries in Asia.

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The study on payment system improvement in Korean firms : The impacts of stock options on pay equity, job attitude and intention to turnover (한국 기업의 보상제도 개선을 통한 경쟁력 제고 방안 : 스톡옵션의 부여에 관한 인식과 보상공정성, 직무태도 및 이직의도와의 관계에 관한 연구)

  • Cha, Sung-Ho;Yang, Dong-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.2
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    • pp.267-278
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    • 2011
  • This study examines the relationship among stock options, pay equity, organizational commitment. Employees who received stock options tend to perceive their pay more equitable and the tendency shows a positive relationship among the amount of stock options and the equity perception. Also employees who received stock options perceive greater procedural equity, as they recognize stock options are awarded to many employees. However, the perception of stock options was not significantly associated with organizational commitment, turnover intention, and pay satisfaction. In 2003, the study surveyed 115 employees who received stock options in 10 publicly owned Korean firms that introduced stock option plans. The statistical analysis leads to the conclusions as follows. First, as the number of stock options increases, the receiver tends to perceive that pay system is more distributively equitable. Second, as the number of stock option receivers increases, the employees perceive the pay system more procedurally equitable. Third, stock option payments don't ensure that it improves pay satisfaction, turnover intention, and organizational commitment. This study shows a positive relationship that stock options work favorably in terms of pay equity, but the effect doesn't seem to be widely positive. The reason is that the introduction of stock options in domestic firms has been made only recently after the foreign exchange crisis in the late 1990s. More experiments and design issues should be discussed for the future.

Influence of the Levee-burning on the Fauna of Insect Pests and Their Natural Enemies (쥐불놀이 (논둑태우기)가 해충 및 천적상에 미치는 영향)

  • 김홍선;이영인;이해빈
    • Korean journal of applied entomology
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    • v.29 no.3
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    • pp.209-215
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    • 1990
  • Some preliminary studies were conducted to find out whether the levee-burning could justifiable for the suppression of insect pests, particularly the smaller brown planthopper (Laodelphax striatellus F.). Density surveys on pests and their enemies (mostly spiders) were carried out upto the mid May at an experimental paddy field located in Suwon after of it's levee $(72\times1m)$ was burned on Feb. 20, 1987. Results were discussed in relation to density recovering of both pests and their possible enemies (spiders) and summarized as below. Not a single individual of any pest or enemy was found from the levee upto sometime after the levee-burning. Grasses started to grow more vigorously in burned ares than in unburned upto about 60 days after the burning. And densities of both pest and enemies grew higher in burned areas than in unburned from about 75 days after the burning (in Early may). It is suspected that all individuals of pests and enemies fond from the burned areas could have immigrated from the surrounding areas. If levee-burning was carried out in much wider areas, much longer time would be needed to recover the density of both pests and enemies to the center region of the burning. Wingless spiders would require even longer time than winged pest species to re-establish in the center region of the widely burned field. Pirata subpiraticus, the most abundant spider species in Korean paddy fields, starts to move about and searches for food at above $9^{\circ}C$ which is somewhat lower than the critical temperature for the pest species. Thus P. subpiraticus would require more food than other pest species early in the spring, and therefore, it would have lower probability to survive than pest species particularly in burned areas. Experiments for pest suppression with levee-burning would better be carried on in much wider areas, and its justification seems to be discussed after man other disciplines related to both pests and their natural enemies were throughly studied together with their density surveys. However, according to the present point of vie, the opinion that levee-burning is helpful for controlling pests which over winter on levee areas could not be justifiable.

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Sedimentary Characteristics and Evolution History of Chenier, Gomso-Bay tidal Flat, Western Coast of Korea (황해 곰소만 조간대에 발달한 Chenier의 퇴적학적 특성과 진화)

  • 장진호;전승수
    • 한국해양학회지
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    • v.28 no.3
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    • pp.212-228
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    • 1993
  • A chenier, about 860 m long, 30 to 60 m wide and 0.6∼1.6 m high, occurs on the upper muddy tidal flat in the Gomso bay, western coast of Korea, It consists of medium to fine sands and shells with small amounts of subangular gravels. Vertical sections across the chenier show gently landward dipping stratifications which include small-scale cross-bedded sets. the most probable source of the chenier is considered to be the intertidal sandy sediments. Vibracores taken along a line transversing the tidal flat reveal that the intertidal sand deposits are more than 5 m thick near the low-water line and become thinner toward the chenier. The most sand deposits are undertrain by tidal muds which occur behind the chenier as salt marsh deposits. C-14 age dating suggests that the sand deposits and the chenier are younger than about 1,800 years B.P. The chenier has originated from the intertidal sand shoals at the lower to mid sand flat, and has continuously moved landward. A series of aerial photographs (1967∼1989) reveal that intertidal sand shoals (predecessor of the western part of chenier) on the mid flat have continuously moved landward during the past two decades and ultimately attached to the eastern part of the chenier already anchored at the present position in the late 1960s. Repeated measurements (four times between 1991 and 1992) of morphological changes of the chenier indicate that the eastern two thirds of the chenier, mostly above the mean high water, has rarely moved whereas the western remainder below the mean high water, has moved continuously at a rate of 0.5 m/mo during the last two years (1991∼1992). This displacement rate has been considerably accelerated up to 1.0 m/mo in winter, and during a few days of typhoon in the summer of 1992 the displacement amounted to about 8∼11 m/mo for the entire chenier. these facts suggest that macro-tidal currents, coupled with winter-storm waves and infrequent strong typhoons, should play a major role for the formation and migration of chenier after 1,800 B.P., when the sea level already rose to the present position and thereafter remained constant.

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A study on health education content analysis in middle school curriculum (중학교 교과과정에 따른 보건교육 내용 분석 연구)

  • You, Jai Bok
    • Journal of the Korean Society of School Health
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    • v.3 no.1
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    • pp.59-72
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    • 1990
  • The study reserches the related contents of the health education in the existing gymnastics and the domestics textbook, catches learning-Ulaching contents by the health-control function and compares the contents with the health-education curriculum of the Texas State in America. This study is questioned and reserched the general features of the teachers who is change in the health education, their attitudes about the teaching of it, and the recognition degree about their health education. The results above is like the following. 1. Learning-teaching contents by the health-control function. The domestics and gymnastics which contains the health education contents, is not discripted continually and at the same time is short of the contents in the health-control function according to the students' individual domains. Also the recent serious problems, (that is, Smoking, Drinking and Medical poisoning, Emotion, and Psychic domains) were no mentioned. 1) In gymnastics textbook, the physical domains are mentioned 8, 9 in juinor, and senior class, the affective, psychic domains only senior class and the social domains only 1 grade except junior and senior class. Growth-development function is concentratedly stated only 1 grade in physical domains and there is no stated in. The social domains are referred a little in senior class. In cure-recovery functions, the physical domains is being taught in 2, and 3 grade, but not 1 grade. Specially, the social domains are being taught in all grade, but, the affective domains are not at all 2) In the subject of domestics, the physical domains of the daily life functions are taught in all the years, but the emotional, mental domains are taught a little in 1 and 2 grades. The growth-development functions are being taught about the nutrition-health, in the physical parts of all graries, and the emotional-mental, social domains are being taught some in 7 and 8 grade except 3 grade, he cure-recovery functions ere taught in only 1 grade, the contents of rehabilitative functions are not being taught like gymnastics. 2. The general characteristics of the health-education teachers and the health-education. In the calss field, the average age of gymnastics-teachers is from 35 to 40 years old, and it of domestics teachers is from 24 to 29 years old. 1) In the class-hours a week, the gymnastics teachers take lessons 3 hours (75.6%) and the domestics teachers 4 hours (65.6%). In "the health-lessons hours alloted"in a semister, 3 or 4 hours is 38.7% and no hours is 18.0% in gymnastics teachers. On the other hand, there is no hours to teach the health-education in domestics teachers. About the opinion: the health subject must be taught as a independent subject, 42.9% of the gymnastics teachers agreed and 45.3 % of the domestics teachers did. 2) The factors which have an influence upon the health-teachers #. In age, the class lesson hours of a week(r= .0014), the confident manner about the lessons(r= .0485) and the necessity of the lessons (r= .0316) are closely related one another. #. In sexes, the lesson hours a class(r= .0000), the alloted hours of health lesson a semister(r= .0000) the confident manner about the class(r= .0001). the quantity of lesson(r= .0001): and, the teacher's belief(r= .0264) are co-related one another. #. In subject in change. the class hours a week(r= .0000), the alloted hours of health-lesson a semister(r= .0000) the quantity of the lesson(r= .0114) are co-related each other. #. In majority, the class lesson hours a week(r= .0000) the alloted hours of health lesson a semister(r= .0000) the quantity of the lesson are co-related each other. The quantity of lesson and the confidence about the lesson (r= .3223) and the quantity of lesson and the interest of lesson (r= .2450) are co-related each other.

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A Study on the Knowledge and Attitude about Sex in One Commercial Girls' High school in Seoul (서울지역 일 여자 상업고등학교의 성에 대한 지식 및 태도에 관한 연구)

  • Kim, Eun Hee
    • Journal of the Korean Society of School Health
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    • v.4 no.2
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    • pp.100-118
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    • 1991
  • This study was conducted in order to grasp the condition of the student's knowledge and attitude about sex. And to offer the basic materials for sex education of school health service. The objects were comprised of 464 volunteered students who study in commercial girls' high school. The material of this study was the questionaire suited to the purposed of this research which has been made through studying references. All the questionaire written by students. The self reported questionaires were collected immediately without explanation on supervision of school nurse. The data was collected from 28th to 30th of June on 1990. Analysis of the data was done utilizing SPSS for percentage, mean, ANOVA and Pearson Correlation Coefficients. The Results are as follows; 1. General features of the objects of study School grade distribution was similar. Fathers of 41-50 years were the highest(58.3%), mothers of 41-50 years were the highest(64.3%), family of living together were the highest(87.5%), fathers of graduated high school were highest(60.7%), mothers of graduated middle school were the highest(43.0%) and neuclear families were highest(91.5%). 2. The Conditions of Knowledge about sex When 5 Point was given to "Well known" and 1 point was given to "Never known", the total average was 2.97, Especially the mean of Female physiology was shown 3.93, 73.4% of students have known. But the mean of male physiology was shown 2.23, 17.2% of students only. And Family planning item was 3.54, hymen item was 3.38, female genitalia item was 3.35, abortion item was 3.25, Intercourse and pregnancy item was 3.24, Ovulation item was 3.02, Contraception item was 2.97, Veneral disease and masturbation item was 2.82, maintenance of pregnancy item was 2.76, Anatomical differences between male and female item was 2.59, male genitalia item was 2.31, ejaculation item was 2.27. 3. The conditions of attitude about Sex When 5 point was given to "Very affirming" and 1 point was given to "Very deny" the total average was 3.20. Especially the mean of social intercourse between other sex was shown 3.92, 73.4% of students have affirmed. But the mean of psychic response on menstruation was shown 2.24, 8.8% of students only. And baby birth item was 3.72, the fact that I am a woman item was 3.53, marriage item was 3.49. Secondary body change item was 3.38, puberty item was 3.31, delivery and sexual intercourse item was 3.05, pregenancy item was 3.02, psychic condition on menarche item was 2.50. Also present counsellors about sex were teachers in charge (44.9%), friends(21.6%), mothers(20.6%), elder sisters (10.6%), mass-communications (1.5%), fathers (0.4%), school nurses and elder brother(0.2%). In addition to, future counsellors about sex were friends (37.7%), mothers(30.6%), elder sister (18.4%), school nurses (4.6%), mass communication (3.8%), teachers in charge (2.5%), elder brothers (1.4%) and fathers(1.0%). 4. Correlation between the general features and knowledge variables School grade and knowledge condition has relationship to female genitalia(P<0.05), female physiology (P<0.00), male physiology (P<0.05),ovulation (P<0.00), and femily planning (P<0.005). Fathers age and knowledge condition has relationship to male physiology(P<0.05), and abortion (P<0.05). Marrital status and knowledge condition has relationship to female physiology (P<0.01), masturbation (P<0.05). Fathers educational background and knowledge condition has relationship to masturbation (P<0.00). Mothers age and knowledge condition has relationship to family planning (P<0.05). 5. Correlation between the general futures and attituded variables Fathers age and attitude condition has relationship to psychic response on menstruation (P<0.05). Mothers age and attitude condition has relationship to fact that I am a woman (P<0.00). Mothers educational background and attitude condition has relationship to social intercourse between other sex (P<0.05). Type of family and attitude condition has relationship to puberty (P<0.01). 6. Correlation between knowledge condition and attitude condition Those who had more knowledge about sex have more affirmative response (P<0.001).

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A Study of the Ethical Values of EMT students (응급구조과 학생의 윤리적 가치관에 관한 연구)

  • Kim, Mi-Seon
    • The Korean Journal of Emergency Medical Services
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    • v.5 no.1
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    • pp.37-51
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    • 2001
  • This study is aimed at examining the ethical values of EMT students. The results below are based on the revised questionnaires, which can be applicable to EMT from the original questionnaires developed by Lee(1990), with a sample of 124 students consisting of 63 first and 61 second year students, conducted November 2-8, 2001. Data were analyzed using SPSS in terms of means, standard deviations, t-test, ANOVA, Pearson's correlation coefficient. The results are as follows: 1. In the area of Human life, all subjects showed utilitarian disposition. All respondents perceived the item "When patients recognizing there is no hope for survival ask for euthanasia, it is ethically right to accommodate their opinions." as the most utilitarian item, whereas they perceived the item "When an hopeless patient is on cardiac arrest, it is ethically right to do CPR as the most deontoogical item. 2. In the area of patient relationship, all students of two groups took on deontoogical characteristics, but there were no statistically significant differences between two groups. All students perceived an item "EMT have to keep it secret if patients disclose their suicide intentions and ask for absolute secrecy" the most utilitarian item, whereas they perceived an item "Even though patients act and speak in a very rude manner, EMT people should do their best to provide care for patients." as the most deontoogical item. 3. In the area of task relationship, first year students perceived an item "Given time limitations, it is ethically right to give priority to the patients who can be rehabilitated over the patients who can't be fully recovered." as the most utilitarian item, whereas second year students perceived an item "Under no circumstances should any placebo be administered to patients." as the most utilitarian item. All students perceived an item "When EMT students see an unconscious person lying in the street, they have to give him/her emergency treatment." as the most deontoogical item. 4. In the area of coworker relationship, all students of two groups took on deontoogical disposition, but there were no significant differences between two groups. All students of two groups perceived an item "Suppose you are regarded as the person who would be promoted. However, you think that your coworker is more competent than you. In that case you should tell your supervisor about your coworker." as the most utilitarian item. First year students perceived an item, whereas second year students perceived an item "When you observe coworkers' misconduct at work, it is ethically right to ignore their misdeeds." as the most deontoogical item. 5. This study demonstrated that for the first year students, there is a correlational relationship between areas of human life and task relationship, and between areas of task relationship and coworker relationship, whereas for the second year students, there is a correlational relationship between areas of human life and task relationship. 6. In areas of human life and task relationship, there are significant differences according to attitudes toward EMT and attendance at ethics training sessions. In the area of coworker relationship, there are significant differences according to religion, attendance at ethics training sessions, and a code of ethics. Recommendations for future research, 1. Sample items to measure ethical values and the instrument tailored to the needs of EMT should be developed. 2. A longitudinal study to track ethical value changes according to the amount of work experience is needed. 3. A code of ethics and/or ethics training, which could apply in actual situations, should be implemented.

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