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A Study on An Integrated GEO/TES with Geothermal Heat Exchanger and Thermal Ice Storage (지중열 교환기와 빙축열조(Thermal Ice Storage)를 연계시킨 통합 지중열-빙축열조 시스템(Integrated GEO/TES))

  • Lohrenz ED.;Hahn Jeongsang;Han Hyuk Sang;Hahn Chan;Kim Hyoung Soo
    • Economic and Environmental Geology
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    • v.38 no.6 s.175
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    • pp.717-729
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    • 2005
  • Peak cooling load of large buildings is generally greater than their peak heating load. Internal and solar heat gains are used fur selection of adquate equipment in large building in cold winter climate like Canada and even Korea. The cost of geothermal heat exchanger to meet the cooling loads can increase the initial cost of ground source heat pump system to the extend less costly conventional system often chosen. Thermal ice storage system has been used for many years in Korea to reduce chiller capacity and shift Peak electrical time and demand. A distribution system designed to take advantage of heat extracted from the ice, and use of geothermal loop (geothermal heat exchanger) to heat as an alternate heat source and sink is well known to provide many benifits. The use of thermal energy storage (TES) reduces the heat pump capacity and peak cooling load needed in large building by as much as 40 to $60\%$ with less mechanical equipment and less space for mechanical room. Additionally TES can reduce the size and cost of the geothermal loop by 1/3 to 1/4 compared to ground coupled heat pump system that is designed to meet the peak heating and cooling load and also can eliminate difficuties of geothermal loop installation such as space requirements and thermal conditions of soil and rock at the urban area.

A Study of the Relationship of Nurses' Personality Type and Job Satisfaction Level, according to the Career (근무경력별 간호사의 성격유형과 직무만족도와의 관련성(MBTI이용))

  • Park Young Sook;Park Kyung Min;Park Jeong Sook;Koh Hyo Jung;Kwon Young Sook;Kim Myung Ae;Kim Chung Nam;Park Cheong Ja;Shin Yeong Hee;Lee Kyung Hee;Lee Byung Sook
    • Journal of Korean Public Health Nursing
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    • v.15 no.2
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    • pp.301-313
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    • 2001
  • This study was to explore the relationship between nurses' personality type and their job satisfaction level. The subjects of the study were the 364 nurses who were serving at the general surgical department, psychiatric department, pediatric department and emergency room. The hospitals for which they were working were four university hospitals in Daegu and Busan, and six other university hospitals in Seoul were selected as sample hospitals. For data collection, questionnaires were self-reported to the subjects, under their agreement, from May to June, 2000. The following two instruments were used in the study: One was MBTI Test whose Korean version designed and verified to reliability and validity by Kim Jung Taek and Shim Hae Sook(1990): the other was the Nursing Job Satisfaction Instrument, 'The Index of Work Satisfaction' developed by Slavitt, et al.., (1978). The data were analyzed by frequency, t-test, one-way variance analysis, scheffe's post hoc contrast, and Pearson correlation coefficient with SPSS Win 10.0 program. The results this study were as follows ; 1. As a result of testing nurse's personality type by function at each career, it's found that the most personality type was expressed by the ST-type$(37.3\%)$ at 1-5 years, the SF-type$(29.4\%)$ at 6-10 years, the ST-type$(43.3\%)$ at more than 11 years. 2. As a result of testing the disparity in job satisfaction according to career, it appeared that the 6-10 years group showed higher job satisfaction, followed by the 6-10 years$(119.6\%),\;1-5 years(118.6\%)\;and\;more\;than\; 11 years(117.7\%)$ groups. 3. As a result of testing job satisfaction level according to nurse's personality type by function at each career, it's found that the most job satisfaction was expressed by the SF-type(F=8.50, p=0.00l) at 1-5 years. the ST-type(F=30.61, p=0.001) at 6-10 years. the SF-type(F=4.98, p=0.003) at more than 11 years groups. 4. As a result of testing a significant correlation between nurse's personality type by function and job satisfaction level. the SF(r=0.279, p=0.001) and ST(r=0.222, p=0.001) types showed significant positive correlation. and the NF(r=-0.201, p=0.001) and NT(r=-0.402, p=0.001) types revealed significant negative correlation. The nursing management is likely to be done more effectively, if managers in charge of nursing administration carefully reflect nurses' personal opinions in posting and personnel management, keeping in mind that there is a specific personality type that serves to raise job satisfaction at a specific career.

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Performance Test of Portable Hand-Held HPGe Detector Prototype for Safeguard Inspection (안전조치 사찰을 위한 휴대형 HPGe 검출기 시제품 성능평가 실험)

  • Kwak, Sung-Woo;Ahn, Gil Hoon;Park, Iljin;Ham, Young Soo;Dreyer, Jonathan
    • Journal of Radiation Protection and Research
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    • v.39 no.1
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    • pp.54-60
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    • 2014
  • IAEA has employed various types of radiation detectors - HPGe, NaI, CZT - for accountancy of nuclear material. Among them, HPGe has been mainly used in verification activities required for high accuracy. Due to its essential cooling component(a liquid-nitrogen cooling or a mechanical cooling system), it is large and heavy and needs long cooling time before use. New hand-held portable HPGe has been developed to address such problems. This paper deals with results of performance evaluation test of the new hand-held portable HPGe prototype which was used during IAEA's inspection activities. Radioactive spectra obtained with the new portable HPGe showed different characteristics depending on types and enrichments of nuclear materials inspected. Also, Gamma-rays from daughter radioisotopes in the decay series of $^{235}U$ and $^{238}U$ and characteristic x-rays from uranium were able to be remarkably separated from other peaks in the spectra. A relative error of enrichment measured by the new portable HPGe was in the range of 9 to 27%. The enrichment measurement results didn't meet partially requirement of IAEA because of a small size of a radiation sensing material. This problem might be solved through a further study. This paper discusses how to determine enrichment of nuclear material as well as how to apply the new hand-held portable HPGe to safeguard inspection. There have been few papers to deal with IAEA inspection activity in Korea to verify accountancy of nuclear material in national nuclear facilities. This paper would contribute to analyzing results of safeguards inspection. Also, it is expected that things discussed about further improvement of a radiation detector would make contribution to development of a radiation detector in the related field.

A Study on Education Need and Satisfaction of the KNOU Nursing Students (방송대 간호학생의 교육요구 및 만족에 관한 연구)

  • Lee, Sun-Ock;Kim, Young-Im;Lee, Sang-Me
    • The Journal of Korean Academic Society of Nursing Education
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    • v.2
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    • pp.75-94
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    • 1996
  • This survey study was aimed at identifying the degree of educational need of the KNOU(Korea National Open University) nursing students defined as admission purposes, satisfaction of distance learning education, learning methods, and courses after graduation. Among randomly assigned 1000 students, 320 KNOU nursing students who allowed to participate in the study completed the questionnaires. The data were analyzed using descriptive statistics, chi-square test, and t-test, Results of this study were as follows : 1. The admission purposes of the KNOU nursing students were 'in order to get a bachelor's degree(83.8%)', 'to acquire knowledge for task(61.3%)', or 'to be admitted for the graduate school (53.1%)' etc. Comparing the admission purposes by age, tow items- 'to explore new possibilities for myself' and 'excellent curriculum' showed statistically significant differences. These two items were also found to show significant differences by marital status. 2. For the media maintenance, the results showed that students use their own cassett radios(96.3%), VTR(49.4%), TV only for the study (44.1%), personal computer (3.31%), or joining Hitel (6.3%). 3. Listening rates of the radio lecture were 'over 80%(9.1%)', '50-80%(9.1%)', '20-50%(18.1%)', 'below 20%(30%)' and 'never(33.1%)', And record lecture showed listening rates as follows : 'over80%(17.2%)', '50-80%(15.9%)', '20-50%(24.4%)', 'below 20%(27,2%)' and 'never(14.4%)'. 4. The difficulties with KNOU life were 'listening radio lectures(38.8%)', studying by following teaching schedules (37.8%)', 'isolated self-study(10.3%)', and 'appearance in the attending classes(8.1%)'. 5. As for satisfaction with teaching methods, the data showed that 81.2% of the respondents were satisfied (or very satisfied) with 'attending classes' and 75%, with 'paper lectures'. On the other hand some of respondents were very dissatisfied with 'recorded lecture(12.8%)' and 'radio lecture(10.9%)' 6. The results also showed that the students want to have 'video conferencing lecture(77.2%)', 'cable TV(64.1%)' and 'CD ROM program' to improve learning effects. 7. Concerning learning attitudes, 48.8% of the students reported 'study mainly for examnination', and only 4.1% answered 'study every day with plan'. The learning attitude showed significant differences by marital status and age. The students also evaluated themelves as 'study very hard(5.9%)', 'study hard in general(41.6%)', 'study a little(40.3%)' and 'study little(11.9%)'. 8. The students responded the most effective learning material was the 'textbook (92.2%)'. 9. For the purposes of using the local center, the results showed 'for the attending classes(76.3%)', 'for the use of references(14.7%)', and 'for the study group(66.7%)'. 10. The results revealed that 20.3% of the respondents had ever experienced unregistration or temporary withdrawal, and 53.4% among them did not register more than one time. The most common reason for the unregistration was 'due to family affairs or their job (70.8%)'. 11. 88.1% of the respondents answered 'they will graduate without fail'. 12. Regarding the benefits from the KNOU graduation, respondents indicated 'graduate school admission(38.1%)', 'self-confidence in social life(17.5%)', and understanding social problems (10.9%)'. 13. 64.4% of the students showed that they have intention to enter the graduate school. The item 'changing work place' showed statistically significant differences by marital status and age.

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The Characteristics and Medical Utilization of Migrant Workers (외국인 노동자의 특성과 의료이용 실태)

  • Ju, Sun Me
    • Korean Journal of Occupational Health Nursing
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    • v.7 no.2
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    • pp.164-176
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    • 1998
  • This study deals with the current medical utilization for migrant workers and the characteristics of them. The purpose of this study is to provide the basic information to establish proper medical policy. For the study self-made questionnaire was used, which was answered by 453 migrant workers working in the area of manufacturing and non-technical work in 10 cities like Seoul, Inchon, Namyangju, Sungnam, Kwangju, Pyungchon, Kunpo, Kimpo, Masuk in Kyungki-do and Chunan in Chungchungnam-do. Besides, 303 medical records of those who had visited free medical check-up center were analyzed. The period of accumulating data is 6 months, from November 1st, 1996 to April 30th, 1997. The characteristics of migrant workers and current medical utilization are analyzed by percentage and the relation between characteristics and current medical utilization were analyzed using ${\chi}^2$-test, t-test, ANOVA. The finding of this study was as follows : 1) The number of nationality was 16. The first majority was Philippians as 32.0%. Among 16 nationalities Southeastern and Northern Asians were 48.9%, Southwestern Asian was 46.5%, the rest was 7.3%. Men were 81.0%, those who are aged from 26 to 30 were 39.0%, Graduatee from high school 92.7%, Christians 56.3%, unmarried 55.4% and salary from 600,000 Won to 800,000 Won 53.8% averaging monthly payment 669,810 Won. As for their residence, those who resided over 3 years were 31.9% and the illegal residence reached 77.4%. As for Korean language, those who speak in middle level were 5.6%. 2) As for kind of work and circumstances, manufacturing was 81.1%, 4 off-days per month 72.2% and 9-10 working hours per day 42.1%. As for accommodation, residence in fabric was 62.6% and one or two members as roommate 40.2%. 3) The characteristics of health behavior showed that 89.4% of migrant workers had 3 meals, 70.9% of them did not drink alcohol, 73.5% of them did not smoke. 4) As a characteristic of health status, 71.8% of them perceived of their health. 76.1% thought that they had no illness before coming Korea. Among them who recognized their illness, those who had problem in circulatory system was 35.3%, respiratory system ENT 19.1% and nervous system 19.1%.66.2% of those having illness had already had sickness when coming to Korea. 5) During last one month, 79.2% of them were known as ones having no illness. Among the sick, those who had problem in circulatory system was 31.6%, nervous system 23.7% and respiratory system 21.1%. 60.3% of the sick were not cured at that time. 6) Sorting the symptom of those who visited free medical check up, dental care was 24.2%, orthopedic 14.0% and digestive system 13.8%. Teethache was 34.4%, stomach problem 11.6%, upper respiratory inflammation 10.2% and back pain 5.9%. Averagely they visited free medical check up 1-2 times. According to symptom, epilepsy 25.5 times, heart and vascular disease 9 times, constipation 2.8%, neurosis 2.38 times and stomach problem 2.34 times. 7) The most frequently visited medical service by migrant workers was hospital. The most mentioned reason was good healing as 36.3%. The medical service satisfied migrant workers mostly was hospital as 64.3%. The reason of satisfaction was also good healing as 45.9%. 8) 77.2% of respondents did not spend money for medical check. Average monthly medical cost was 25,100 Won, 3.7% of income. Those who had no medical security was 73.4%. In their case, 67.7% got discount from hospital or support from working place and religious organization. 9) As for the difference of medical utilization according for the characteristics of migrant workers, legal workers and no-Korean speaker used hospital more frequently. 10) Those who were satisfied most of all with the service of hospital were female workers, hinduists and buddhists, legal workers or manufacture workers. 11) Christians, those who have 3 meals or recognize themselves as healthy ones mostly had no illness. As a result, the most of migrant workers in Korea are from Asia. They are good educated but are working in manufacturing and illegal. Their average income is under 700,000 Won which in not enough for medical cost. They have no medical security and medical fee is supported by religious organization or discounted. Considering these facts the medical policy by government is to be established.

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Clinical Characteristics of Paradoxical Response to Chemotherapy in Pulmonary Tuberculosis (항결핵제 사용 중 폐병변의 일시적 악화를 보인 환자의 임상상)

  • Kim, Soo-Hee;Chung, Hyo-Young;Lee, Ghie-Dong;Shin, Min-Ghie;Jung, Tae-Sik;Jin, Byung-Cheol;Kim, Hyun-Jung;You, Jin-Jong;Lee, Jong-Deog;Hwang, Young-Sil
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.1
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    • pp.27-35
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    • 2002
  • Background : The paradoxical response refers to an enlargement of old lesions or unexpected new ones during apparently adequate antituberculous therapy. This response has been reported in cases of intracranial tuberculoma, tuberculous lymphadenopathy, tuberculous pleurisy and pulmonary tuberculosis. However, there are few reports on its frequency and clinical characteristics. Materials and Methods : This study enrolled 205 patients who were treated with first line antituberculous agents for more than 6 months. We retrospectively studied 155 patients with pulmonary tuberculosis and 57 patients with pleural tuberculosis (7 patients had both) from July 1998 to March 2000. The patients were divided into the paradoxical response group and the non-paradoxical group. The clinical characteristics of the paradoxical response group and the non-paradoxical group. The clinical characteristics of the paradoxical group were investigated. Statistical analysis was done with an independent sample T-test and Chi-squared test. Results : 29 of the 205 patients(14.1%) had paradoxical response. Among the 29 patients, there were 19 pulmonary tuberculosis, 8 tuberculous pleurisy(2 patients had both). Paradoxical response appeared 32 days (mean 35 days in pulmonary tuberculosis, mean 25 days in tuberculous pleurisy) after the beginning of chemotherapy. The duration to regress less than half of initial chest lesion was 114 days in pulmonary tuberculosis and 124 days in tuberculous pleurisy, respectively. Most common clinical manifestation of paradoxical response patients was coughing in both pulmonary tuberculosis and tuberculous pleurisy. Male sex, high blood WBC count and high level of pleural fluid LDH were related with paradoxical response. Conclusion : These findings suggest that presponse usually appears 1 month and disappears within 4 months after the beginning of anti-tuberculous chemotherapy. Paradoxical response was relatively correlated with male sex, high blood WBC count and high level of pleural fluid LDH.

A Study on the Factors Affecting Subjective Health Index of the Aged in Daejon Area (일부지역 노인들의 주관적 건강수준에 영향을 미치는 요인에 관한 연구)

  • 민경진;김근조;차춘근
    • Korean Journal of Health Education and Promotion
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    • v.18 no.2
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    • pp.1-26
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    • 2001
  • This research is aimed to define how the depression, performing ability of IADL and muscular-skeletal pain of the Aged, according to their residential circumstance, sex and age, can affect the subjective health index and how all these are related and associated with. For the period of June 1 to July 31, 2000, in order to study and define how the depression, performing ability of IADL and muscular-skeletal pain are related to the subjective health index of the Aged, we have conducted an enquete through a direct interview with 693 persons over age sixty-five (65) in Daejon and in other adjacent areas, divided into three different residential types “The Aged living at home”, “The Aged living at welfare facilities” and “The Aged living alone”. We have studied all the data and information obtained through this enquete and have analyzed χ²-test, t-test, ANOVA, analysis of simple correlation, analysis of factor. by SPSS10.0/PC+. The results were as follows: Generally, the four (4) factors depression, IADL performing ability, muscular-skeletal pain and the subjective health index of the Aged, are a lot influenced by and related to their residential circumstance, their sex and their age. With regard to the depression of the Aged by their sex, it was analyzed that, on an average, the female-Aged gains 48.3 point which reflects comparatively the higher points and the female-Aged is more depressed. In analyzing depression of the Aged by their age, it appears that the Aged between eighty (80) to eight-four (84) years of age, gains 49.2 point which is the highest points and simultaneously we could realize that depression follows age, - the more the age gets, the more the depression is increased. In analyzing depression of the Aged by their residential type, it shows that “the Aged living alone” gains 50.9 point and is most depressed. With regard to the IADL performance of the Aged by their sex, it was analyzed that, on an average, the female-Aged gains 23.8 point, which shows the performance of the female-Aged is less independent. In addition, it was also found that the IADL performing ability is becoming less and less independent following their age increasing. In analyzing IADL performance by their residential type, it appears that “the Aged living at welfare facilities” gains the lowest 21.5 point and is least independent. We conclude that some assistances from others are required for the Aged living at welfare facilities in their performing IADL. With regard to the muscular-skeletal pain of the Aged by their sex, it was analyzed that, on an average, the female-Aged gains 3.0 point and the female-Aged suffers from this pain more severely. In analyzing this pain by their residential type, it was found that, on an average, the 3.0 point goes for “the Aged living alone”, which explains the Aged living alone is having the most serious pain. With regard to the subjective heath index of the all Aged participated in this research, the analysis indicates 8.8 point and this is considered as a general standard (7-10 point). In analyzing this index by their sex, the female-Aged gains 8.6 point only and it explains a lot of female-Aged consider they are not really healthy. In analyzing this index by their residential type, “the Aged living at welfare facilities” and “the Aged living alone” gain the comparatively lower point, -respectively 8.4 point for the Aged living at welfare facilities and 8.8 point for the Aged living alone. The Aged of these two residential types express they are obviously in a bad condition of health, which makes us think a lot. With regard to the factors affecting the subjective health index of the Aged, it was analyzed that this index can significantly be influenced by their depression, their pain, their age and by how much they are satisfied with their current living conditions, and also analyzed that the correlative relation certainly exists between the depression and pain, and the subjective health index, - that is, the more the depression and pain are serious, the lower the subjective health index indicates. As for the IADL, it appears that the IADL's relation with this index is not that significant and even not important.

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A Study on the Functional Status in Life and Life Satisfaction for Elderly Residing at Home - Comparing Urban and Rural Elderly - (재택노인의 생활기능상태와 생활만족도에 관한 연구)

  • 이재면
    • Korean Journal of Health Education and Promotion
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    • v.12 no.2
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    • pp.109-119
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    • 1995
  • As the population of elderly in Korea is increasing rapidly since the 1990's and will more rapidly in the 21st Century, the demand of their health care would be a great burden to health care expenditure. Then it would be necessary to contemplate the functional status and life satisfaction for elderly to make them live more independently. The objectives of this study were find out the functional status in life and life satisfaction for the elderly aged 65 or over who had resided in urban area of two Gus in Pusan and rural area of two Myuns in Haman Gun in Kyeognam Province, and to provide basic data for planning systematic health care programme. The study period was two weeks from February 6 to February 18, 1995 and the subjects were 274 elderly of which 143 were urban residents, 131 were rural residents, and the study method was by structured questionnaire. The data were analyzed with SAS/PC/sup +/ programme using Chi-square test, t-test, ANOVA, Pearson's correlation coefficients, and multiple regression analysis. The results were as follows; 1. To see the pattern of living together, those living with partners were the most common, 39.1% ; 37.8% of urban elderly lived with married sons, 32.2% of them lived with partners, but 46.6% of rural elderly lived with partners, 16.8% of them lived with married sons, which showed difference between residence(p<0.005). 2. Elderly who had jobs were 64.1% in rural residents, and 7.7% in urban residents, which showed significant difference(p<0.05). 3. The score of cognitive function of total subjects was 24.7, that of urban elderly was 23.8, and that of rural elderly was 25.7, then it was higher in rural ones and low for old-elders and those who had no jobs. 4. The score of PADL was 26.8 for urban elderly, 30.1 for rural elderly, and that of IADL was 22.2 for urban elderly, 25.6 for rural elderly, which showed higher activities of daily living for rural elderly than urban elderly(p<0.001). 5. The score of domestic performance was 21.9 for urban elderly, and 30.5 for rural elderly, which showed higher score for rural elderly(p<0.001). 6. The score of life satisfaction was 20.7 for urban elderly, 29.8 for rural elderly, then it was higher for rural elderly(p<0.01). 7. As a result of ANOVA for functional status in living by general characteristics; the score of cognitive function differed by age, job; that of PADL differed by age, job, education, and the pattern of living together, that of IADL differed by age, job, and the pattern of living together. The score of domestic role performance differed by age, job, marital status, and the pattern of living together. 8. ANOVA for life satisfaction showed that the score of life satisfaction differed by job(p<0.001) and the pattern of living together(p<0.01). 9. The correlations between functional status in living and life satisfaction showed that the higher the score of cognitive function was(r=0.39), the higher the score of activities of daily living was(r=0.50), and the higher the score of domestic role performance was(r=0.41), the higher the score of life satisfaction. 10. Stepwise multiple regression analysis for life satisfaction pointed out that residence was responsible for 39.9% of the variance. cognitive function was for 5.3%, and domestic role performance was for 1.2%.

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School Dieticians' Perception of Seafood Ingredient Pricing in School Food-Service in Seoul (학교급식 수산물 가격 결정에 대한 서울 지역 학교영양(교)사의 인식)

  • Cha, Myeong Hwa;Seo, Sang Rok;Moon, Min Ji;Yang, Ji Hye;Sung, Bo Mi;Jung, Hyun Suk;Ryu, Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.11
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    • pp.1766-1773
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    • 2014
  • The purpose of this research was to scrutinize dieticians' perspective of seafood ingredients prices in school food-service. Suppliers' contract status, seafood ingredient usage and satisfaction, expectations regarding prices of seafood ingredients, and willingness to pay when HACCP is taken into account were studied. Through random sampling, the survey was conducted on 231 dieticians in 11 different educational districts and 12 elementary, six middle, and three high schools. Ultimately, 142 survey responses were taken into account. Data analysis was performed using SPSS v15.0 by descriptive analysis, ${\chi}^2$-test, and t-test. For contracts regarding seafood ingredients, competitive contracts composed 79.7%. Exactly 42.1% responded that contracts were breached, and 60.1% testified that product returns were due to excessive glazing of ingredients. The satisfaction rate of 'hygiene & sanitation of product' was the highest, whereas 'price of product' was the lowest. For 'recontracting intention', 'informal purchasing' showed higher rates compared to 'competitive bidding'. Reflecting upon the six main price factors, 'designation and maintenance of HACCP', 'price of raw seafood ingredients', 'processing costs', 'margin', 'logistic costs', and 'cost of standardizing seafood ingredients', dieticians' perceived 'impact on the anticipated price' on total cost was lower than present counterparts. This implicates that 'impact on the present price' of the six price factors is too excessive, suggesting that many dieticians are unsatisfied with the current prices of seafood ingredients. Furthermore, 52.8% of dieticians stated that the maximum additional payment of HACCP seafood ingredients should be less than 5%. Consequently, this research serves as basic information for reasonable pricing of seafood ingredients and contributes to increased seafood usage by school food-services.

Functional MRI of Visual cortex in the Patients with Occipital Lobe Ischemia (후두엽의 허혈성 뇌졸중 환자에서 시각피질의 기능적 자기공명영상)

  • 이영준;정태섭;윤영수;한승한;조영재;배준호
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.173-178
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    • 1999
  • Purpose : To evaluate the usefulness of functional MRI (fMRI) of visual cortex in patients with ischemic infarction in the occipital lobe. Materials and Methods : Four patients with the symptoms and signs of visual cortical ischemia were included. Functional MRI was performed by 2D-FLASH technique with the parameter of 90/56msec TR/TE, $40^{\circ}$ flip angle, $240{\times}240{\;}FOV,{\;}64{\times}128$ matrix number, 8.32 seconds acquisition time, 8mm slice thickness. An axial slice including both visual cortices was selected and alternative activation and resting of the visual cortex was performed using red color photostimulator. all patients undertook visual field test, and vascular abnormality was examined by MRA (n=4) and DSA (n=2). fMRI results were compared with the results of a visual field test, conventional MRI and cerebral angiography. Results : On fMRI, decreased activity of the visual cortex was found in the occipital lobe corresponding to stenosis of the posterior cerebral artery or its branch noted on angiogram. However, 2 of 4 patients showed no abnormal findings on conventional MRI. Visual field defect was noted in 3 patients, one and of whom showed no abnormality on conventional MRI and diffusion-weighted image, but revealed decreased activity in the corresponding visual cortex on fMRI. Conclusion : fMRI may be a sensitive method for detection of the status of decreased blood flow or vascular reserve which other methods can not.

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