• Title/Summary/Keyword: 자기연구

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Geomagnetic Field Distribution in the Korean Peninsula by Spherical Harmonic Analysis (구면조화해석(球面調和解析)에 의(依)한 한반도내(韓半島內)의 지구자기장(地球磁氣場)의 분포(分布)에 관(關)한 연구(硏究))

  • Min, Kyung Duck;Lee, Sunhee
    • Economic and Environmental Geology
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    • v.12 no.2
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    • pp.95-104
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    • 1979
  • The position of any point on the earth's surface can be. represented in the spherical coordinates by surface spherical harmonics. Since geomagnetic field is a function of position on the earth, it can be also expressed by spherical harmonic analysis as spherical harmonics of trigonometric series of $a_m({\theta})$ cos $m{\phi}$ and $b_m({\theta})$ sin $m{\phi}$. Coefficients of surface spherical harmonics, $a_m({\theta})$ and $b_m({\theta})$, can be drawn from the components of the geomagnetic field, declination and inclination, and vice versa. In this paper, components of geomagnetic field, declination and inclination in the Korean peninsula are obtained by spherical harmonic analysis using the Gauss coefficients calculated from the world-wide magnetic charts of 1960. These components correspond to the values of normal geomagnetic field having no disturbances of subsurface mass, structure, and so on. The vertical and total components offer the zero level for the interpretation of geomagnetic data obtained by magnetic measurement in the Korean peninsula. Using this zero level, magnetic anomaly map is obtained from the data of airborne magnetic. prospecting carried out during 1958 to 1960. The conclusions of this study are as follows; (1) The intensity of horizontal component of normal geomagnetic field in Korean peninsula ranges from $2{\times}10^4$ gammas to $2.45{\times}10^4$ gammas. It decreases about 500 with the increment of $1^{\circ}$ in latitude. Along the same. latitude, it increases 250 gammas with the increment of $1^{\circ}$ in longitude. (2) Intensity of vertical component ranges from $3.85{\times}10^4$ gammas to $5.15{\times}10^4$ gammas. It increases. about 1000 gammas with the increment of $1^{\circ}$ in latitude. Along the same latitude, it decreases. 150~240 gammas with the increment of $1^{\circ}$ in longitude. Decreasing rate is considerably larger in higher latitude than in lower latitude. (3) Total intensity ranges from $4.55{\times}10^4$ gammas to $5.15{\times}10^4$ gammas. It increases 600~700 gammas with the increament of $1^{\circ}$ in latitude. Along the same latitude, it decreases 10~90 gammas. with the increment of $1^{\circ}$ in longitude. Decreasing rate is considerably larger in higher latitude as the case of vertical component. (4) The declination ranges from $-3.8^{\circ}$ to $-11.5^{\circ}$. It increases $0.6^{\circ}$ with the increment of $1^{\circ}$ in latitude. Along the same latutude, it increases $0.6^{\circ}$ with the increment of l O in longitude. Unlike the cases of vertical and total component, the rate of change is considerably larger in lower latitude than in higher latitude. (5) The inclination ranges from $57.8^{\circ}$ to $66.8^{\circ}$. It increases about $1^{\circ}$ with 'the increment of $1^{\circ}$ in latitude Along the same latitude, it dereases $0.4^{\circ}$ with the increment of $1^{\circ}$ in longitude. (6) The Boundaries of 5 anomaly zones classified on the basis of the trend and shape of anomaly curves correspond to the geologic boundaries. (7) The trend of anomaly curves in each anomaly zone is closely related to the geologic structure developed in the corresponding zone. That is, it relates to the fault in the 3rd zone, the intrusion. of granite in the 1st and 5th zones, and mountains in the 2nd and 4th zones.

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Analysis on the Degree of Cerebral Activity According to Cognition Task in Welders Exposed to Manganese (망간 노출 용접공의 인지수행에 따른 뇌 활성화 정도 분석)

  • Choi, Jae-Ho
    • Journal of radiological science and technology
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    • v.34 no.1
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    • pp.17-25
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    • 2011
  • In this study, we examined the impact caused by chronic exposure to Mn by investigating the degree of brain activation based on the data of recognition activities using fMRI (functional magnetic resonance imaging). A questionnaire survey, blood tests, and fMRI tests were carried out with respect to two groups. Group 1 was an exposure group consisting of 15 male workers who are 34 years old or older, and who worked for longer than 10 years in a shipbuilding factory as a welder. Group 2 was a control group consisting of 15 workers in manufacturing industries with the same gender and age. The results showed that blood Mn concentration of Group 1($1.3\;{\mu}g/dl$) was significantly higher than that of Group 2($0.8\;{\mu}g/dl$)(p < 0.001), and Pallidal Index (PI) of Group 1 was also significantly higher than that of Group 2 (p < 0.001). PI value of the group whose blood Mn concentration was $0.93\;{\mu}g/dl$ or higher was significantly higher than that of the group whose blood Mn concentration was less than $0.93 \;{\mu}g/dl$ (p < 0.001). As for brain activity area within the control group, the right and the left areas of occipital cortex showed significant activity and the left area of middle temporal cortex, the right area of superior inferior frontal cortex and inferior parietal cortex showed significant activity. Unlike the control group, the exposure group showed significant activity on the right area of superior inferior temporal cortex, the left of insula area. In the comparison of brain activity areas between the two groups, the exposure group showed significantly higher activation than the control group in such areas as the right inferior temporal cortex, the left area of superior parietal cortex and occipital cortex, and cerebellum including middle temporal cortex. However, in nowhere the control group showed more activated area than the exposure group. As the final outcome, chronic exposure to Mn increased brain activity during implementation of arithmetic task. In an identical task, activation increased in superior inferior temporal cortex, and insula area. And it was discovered that brain activity increase in temporal area and occipital area was more pronounced in the exposure group than in the control group. This result suggests that chronic exposure to Mn in the work environment affects brain activation neuro-network.

A Patterns of Care Study of the Various Radiation Therapies for Prostate Cancer among Korean Radiation Oncologists in 2006 (Patterns of Care Study를 위한 2006년 한국 방사선종양학과 전문의들의 전립선암 방사선치료원칙 조사연구)

  • Kim, Jin-Hee;Kim, Jae-Sung;Ha, Sung-Whan;Shin, Seong-Soo;Park, Won;Cho, Jae-Ho;Suh, Chang-Ok;Oh, Young-Taek;Shin, Sei-Won;Kim, Jae-Chul;Jang, Ji-Young;Nam, Taek-Keun;Choi, Young-Min;Kim, Il-Han
    • Radiation Oncology Journal
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    • v.26 no.2
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    • pp.96-103
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    • 2008
  • Purpose: To conduct a nationwide academic hospital patterns of the practice status and principles of radiotherapy for prostate cancer. The survey will help develop the framework of a database of Korean in Patterns of Case Study. Materials and Methods: A questionnaire about radiation treatment status and principles was sent to radiation oncologists in charge of prostate cancer treatment at thirteen academic hospitals in Korea. The data was analyzed to find treatment principles among the radiation oncologists when treating prostate cancer. Results: The number of patients with prostate cancer and treated with radiation ranged from 60 to 150 per academic hospital in Seoul City and 10 to 15 outside of Seoul City in 2006. The primary diagnostic methods of prostate cancer included the ultrasound guided biopsy on 6 to 12 prostate sites(mean=9), followed by magnetic resonance imaging and a whole body bone scan. Internal and external immobilizations were used in 61.5% and 76.9%, respectively, with diverse radiation targets. Whole pelvis radiation therapy(dose ranging from 45.0 to 50.4 Gy) was performed in 76.9%, followed by the irradiation of seminal vesicles($54.0{\sim}73.8$ Gy) in 92.3%. The definitive radiotherapy doses were increased as a function of risk group, but the range of radiation doses was wide(60.0 to 78.5 Gy). Intensity modulated radiation therapy using doses greater than 70 Gy, were performed in 53.8% of academic hospitals. In addition, the simultaneous intra-factional boost(SIB) technique was used in three hospitals; however, the target volume and radiation dose were diverse. Radiation therapy to biochemical recurrence after a radical prostatectomy was performed in 84.6%; however, the radiation dose was variable and the radiation field ranged from whole pelvis to prostate bed. Conclusion: The results of this study suggest that a nationwide Korean Patterns of Care Study is necessary for the recommendation of radiation therapy guidelines of prostate cancer.

Understanding the Legal Structure of German Human Gene Testing Act (GenDG) (독일 유전자검사법의 규율 구조 이해 - 의료 목적 유전자검사의 문제를 중심으로 -)

  • Kim, Na-Kyoung
    • The Korean Society of Law and Medicine
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    • v.17 no.2
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    • pp.85-124
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    • 2016
  • The Human gene testing act (GenDG) in Germany starts from the characteristic features of gene testing, i.e. dualisting structure consisted of anlaysis on the one side and the interpretation on the other side. The linguistic distincion of 'testing', 'anlaysis' and 'judgment' in the act is a fine example. Another important basis of the regulation is the ideological purpose of the law, that is information autonomy. The normative texts as such and the founding principle are the basis of the classification of testing types. Especially in the case of gene testing for medical purpose is classified into testing for diagnostic purpose and predictive purpose. However, those two types are not always clearly differentiated because the predictive value of testing is common in both types. In the legal regulation of gene testing it is therefore important to manage the uncertainty and subjectivity which are inherent in the gene-analysis and the judgment. In GenDG the system ensuring the quality of analysis is set up and GEKO(Commity for gene tisting) based on the section 23 of GenDG concretes the criterium of validity through guidelines. It is also very important in the case of gene testing for medical purpose to set up the system for ensurement of procedural rationality of the interpretation. The interpretation of the results of analysis has a wide spectrum because of the consistent development of technology on the one side and different understandings of different subjects who performs gene testings. Therefore the process should include the communication process for patients in oder that he or she could understand the meaning of gene testing and make plans of life. In GenDG the process of genetic counselling and GEKO concretes the regulation very precisely. The regulation as such in GenDG seems to be very suggestive to Korean legal polic concerning the gene testing.

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Risk Factors and Prognosis for Periventricular Leukomalacia According to Neuroimage in Preterm Infants (미숙아 뇌실주위 백질연화증에서 뇌영상 분류에 따른 예후와 위험인자)

  • Ahn, Jung-Hee;Seo, Yoo-Jin;Yoon, Jung-Rim;Shim, Gyu-Hong;Kim, Seong-Hee;Cho, Woo-Ho;Chey, Myoung-Jae
    • Neonatal Medicine
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    • v.17 no.1
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    • pp.64-74
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    • 2010
  • Purpose : The aim of this study was to determine the risk factors, clinical characteristics and prognosis for the development of periventricular leukomalacia (PVL) in preterm infants according to the extent and site of the PVL. Methods : The medical records of infants (under 36 weeks of gestational age) delivered from January 1999 to December 2008 were reviewed. Twenty-five preterm infants with were PVL were diagnosed by brain magnetic resonance imaging (MRI) and an addition 50preterm infants with no brain lesions were enrolled in this study. The perinatal and neonatal risk factors for the development of PVL was determine in these infants. Mental and Psychomotor Developmental Indices (MDI, PDI) were assessed by a clinical psychologist using the Bayley Scales of Infant Development II. We compared the differences of the clinical characteristics and prognosis according to brain MRI findings. Results : Maternal fever, young maternal age, extended oxygen use, hypotension within the first week of birth, use of inotropics within the first week of birth, and respiratory distress syndrome were the risk factors associated with PVL (P <0.05). In the multivariate analysis, maternal fever and extended oxygen use were statistically significant independent risk factors (P <0.05). The mean MDI and PDI scores of the PVL group (74.4$\pm$ 27.8 and 58.0$\pm$17.7) were significantly lower than those of the control group (103.5$\pm$8.9 and 101.7$\pm$16.1, P <0.05). Conclusion : Maternal fever and extended oxygen use were independent risk factors for PVL. We should pay attention to infants who had the risk factors and follow them up closely by brain imaging study and Bayley Scales of Infant Development II.

An Analysis and Evaluation of Current Cyber Home Learning Contents - Focused on the Earth Science Area of Science Course for the 10th Grade- (현행 사이버가정학습 콘텐츠의 분석 및 평가 -고등학교 1학년 과학과정의 지구과학 영역을 중심으로-)

  • Na, Jae-Joon
    • Journal of Science Education
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    • v.34 no.2
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    • pp.225-236
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    • 2010
  • The purpose of this study is to analyze and evaluate the Cyber Home Learning contents of Earth science area in the basic course of the $10^{th}$ grade. For this purpose, we applied the 'Cyber Home Study Content Quality Control Tool' presented in Elementary Secondary Education e-Learning Quality Management Guidelines (Ver.2.0)' of Korea Education & Research Information Service(2008). The results of Cyber home learning contents analysis are as follow: First, it was presented that the study guide introduced the contents which should be studied for one class, properly. And it was not analyzed that the diagnosis assesment was not completed in the initiative study; Second, it was possible to study choosing the contents fitting the learner's level of learning in the main study, it was comprised of about 10 minutes. Third, it was performed without feedback for incorrect answers in the learning assessment, just the number of wrong questions. And the learning arrangement present the important contents learned in that class, summarizing and arranging again. The results of evaluating the contents in Cyber Home Learning are as follows: First, in evaluation section of instructional design, many text materials which were so difficult for learners to read were explained, being provided. Besides, the systematic structures leaves much to be desired, in view of learners' learning experience, contents, and environment. And in evaluation section of learning contents, the error of contents caused the learning contents not to appear, the amount of learning in each section was found too much. Second, in evaluation section of the strategy for Teaching and Learning, when we mention the strategy of Self Directed Learning, the environment to make learners search for information free and self-study possible was not possessed well. And in evaluation section of interaction, it was found that a simple click caused the learning to go on. Third, in evaluation section of evaluating, it was evaluated that there was wanting in consistency in learning aims, contents, evaluation contents.

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Perceptions of the Retailers within Green Food Zone on the enforcement of the Special Act on the Safety Management of Children's Dietary Life (어린이 식생활 안전관리 특별법 시행에 대한 학교주변 판매업자 인식조사)

  • Lee, Seung-Sin;Yang, Deok-Soon;Lee, Jong-Hye;Lee, Young-Hee;Heo, Sun-Kyung
    • Journal of Food Hygiene and Safety
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    • v.27 no.1
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    • pp.55-62
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    • 2012
  • This study is a survey of regulatees' perception on main contents and enforcement effect of the Act, the retailers at food stores within Green Food Zone, for the effective enforcement of "The Special Act on the Safety Management of Children's Dietary Life" legislated in 2008. Percentage, frequency analysis, and T-test are derived from the survey carried out to the 175 retailers at food stores within Green Food Zone, across the country except Jejudo, for the two months March and April of 2011. The survey results are as follows. Over 80% of the respondents are aware of comprehensive policy for child food safety and the enforcement of 'the Special Act' and considering the rate of satisfaction on food safety information provided by government, over 90% of the respondents, virtually most of them, are satisfied. The rate of awareness of Green Food Zone is about 80% and that of outstanding business for children is about 50%, showing little perception of it. The comparison of the survey result of 2011 with that of 2010, which have the same questions to the retailers within Green Food Zone, still indicates a need for enhancement of understanding on absolute standard, though it showed fairly better improvement in general. Several proposals are given in this study based on the survey results, which will contribute to the children food safety and health improvement in the end.

The Maize with Multiple Ears and Tillers (MET) III. Developmental Habit and Morphology of the Tillers (다얼성 옥수수 연구 III. 분얼발생의 습성 및 형태)

  • Choe, Bong-Bo;Lee, Hee-Bong;Lee, Won-Koo;Kang, Kwon-Kyoo;Jong, Seung-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.1
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    • pp.23-29
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    • 1989
  • In order to investigate developmental habit and morphology of maize tillers, time and location of tiller development. number of tillers per plant, tiller angle, height and diameter of tillers and root systems of tillers were examined under field condition for maize with tillers. Materials used were mostly from Korean local lines and a few lines from other countries were also included for comparison. The time of the first tiller development was about 18 to 20 days after emergence when planted on May in Yusong. The second tiller appeared about 4 to 5 days after the first tiller appeared. The tiller number per plant varied with lines and hybrids and ranged from two to ten. The location of tiller development was usually basal nodes of the main stem. Each tiller appeared to have its own root system. The angle between tillers and main stem was variable depending upon the maizes and the tiller angle could be classified into three categories. The height of tillers was also variable and seemed to be under genetic control. The most productive tillers were found among the Korean local derivatives.

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Autoradiographic Studies on the Inhibitory Effect of Dibutyryl Cyclic AMP on Mouse Oocyte Maturation in Vitro (Dibutyryl Cyclic AMP가 생쥐여포난자의 성숙에 미치는 억제효과에 관한 자기방사법적 연구)

  • Choi, Choon-Keun
    • Applied Microscopy
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    • v.7 no.1
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    • pp.21-43
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    • 1977
  • This experiment was undertaken in order to localize the labeled dbcAMP (dibutyryl cyclic AMP) in oocytes whose development has been suppressed by cold dbcAMP for 6 or 19 hours in vitro. Mouse oocytes were obtained from the ovaries of 3-4 week old A strain female mice, by puncturing the Graafian follicles in the modified Krebs-Ringer bicarbonate salt solution under the dissecting microscope. Those oocytes which have intact germinal vesicle were cultured in the basic culture medium supplemented with 0.4% bovine serum albumin (BSA). Cultivation of the oocytes was carried out in a microtube developed by Cho (1974). The cultures were then incubated in a humidified 5% $CO_2$ incubator maintained at $37^{\circ}C$ for 6 or 19 hours (Donahue, 1968). DbcAMP was added to culture medium for a final concentration of 100ug/ml, and $^3H-dbc$ AMP (specific activity 13 Ci/mM) for a final concentration of $40{\mu}Ci/ml$ was also added to the medium. For electron microscopic autoradiography, those oocytes recovered from the culture were washed with phosphate buffer (pH 7.4), and immediately prefixed in a 2.5% glutaraldehyde overnight and postfixed for 2 hours at $4 ^{\circ}C$ in 1% osmium tetroxide in phosphate buffer with pH 7.4 (Palade, 1952). After fixation, the materials were dehydrated in graded alcohol series and embedded in Epon 812 mixture based on the standard procedures (Luft, 1961). The thin sections $600-700{\AA}$ thick were mounted on the grids of 200 meshes. The grids containing sections were coated with a nuclear emulsion Kodak NTB-3 and stored in a cold dark box (at $4^{\circ}C$) for 3 weeks. After exposure, the samples were developed with Kodak D-19 and stained with uranyl acetate and lead citrate. Routine observation was made with Hitachi HU-11E electron microsocope. The results of the observation were as followings: 1. It was found that the labeled dbcAMP penetrated the egg plasma membrane and dispersed at random in the cytoplasm. 2. It was also observed that most of the labeled dbcAMP was attached to microfibrillar lattices portion of the oocyte cytoplasm. There fore, it is presumed that the receptor of the dbcAMP is localized in the microfibrillar lattices of the oocyte. 3. It also seems that some other cell organells such as mitochondria, Golgi complex, cortical granules are not directly related to the action of the dbcAMP. 4. The labeled dbcAMP was neither observed in the membrane nor in the nucleus. Therefore, it seems that there is no relationship between the concentration of dbcAMP and the nuclear membranous permeability. 5. There was no difference in number of dbcAMP particles when oocytes were cultured for 6 hours and 19 hours. 6. However, it was observed that, in same of the oocytes suppressed in germinal vesicle by dbcAMP for 19 hours, cell organells were moved and concentrated to a small portion of the cytoplasm, and that the morphology of the organells greatly changed to an abnormal. form. Therefore, it is supposed that those oocytes were in the process of degeneration. From the above results, it is expected that dbcAMP penetrated the egg membrane and was bound to the receptor which seems to be located in the microfibrillar lattiees portion, and that this dbcAMP-receptor complex inhibited some enzyme system of the oocytes which are essential for the germinal vesicle breakdown.

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A Study on Nutrition Status by Diet of Female College Students of Masan City - 1. Focus on Diet Survey - (여대생의 체중감량이 영양상태에 미치는 영향 - 제1보. 다이어트 실태조사를 중심으로 -)

  • 김종현
    • The Korean Journal of Food And Nutrition
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    • v.11 no.2
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    • pp.185-191
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    • 1998
  • This study was performed to investigate the nutrition status by weight loss(diet) of 287 female college students, focus on questionnaire about diet survey. The subjects mainly had irregularly one or two meal per a day so food behavior was not good. Over half of subjects had a tendency to overestimate body shape of self. The desired weight(46.95$\pm$0.39kg) was significant lower than real weight(50.32$\pm$0.9)(p=0.0114). The time when diet is first tried was mainly after high school(94.51%). Mean weight loss was 1~4kg but most of subjects didn't maintain the lost weight. The diet approach method tried was sequently the fasting 1 meal or the more in a day(23.61%), exercise(21.92%), restricting calories(15.85%) etc. The source of diet was orderly newspaper or magazine(30.86%), friends or relatives or family(28.86%) etc. The group who recognized the self body shape was normal or a little fat had higher self notion of health than other groups.

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