• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.147-158
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• 2004

Laboratory dynamic tests are carried out to assess the liquefaction potential of saturated sands in most countries. However, simple results such as the maximum cyclic shear stress and the number of cycles at initial liquefaction are used in the experimental assessment of liquefaction potential, even though various results can be obtained from the dynamic test. In addition, it seemed to be inefficient because more than three dynamic tests with different stress ratio have to be carried out to draw a liquefaction resistance experimental curve. To improve the present assessment method fur liquefaction potential, a new critical resistible characteristic far soil liquefaction is proposed and verified through conventional cyclic triaxial tests with Jumunjin sand. In the proposed method, various experimental data such as effective stress path, stress-strain relationship, and the change of excess pore water pressure can be used in the determination of cumulative plastic shear strains at every 1/4 cycle. Especially, the critical cumulative plastic shear strain to initiate liquefaction can be defined in a specific point called a phase change point in the effective stress path and it can be calculated from a hysteric curve of stress-strain relationship up to this point. Through this research, it is found that the proposed cumulative plastic shear strain can express the dissipated energy to resist dynamic loads and consider the realistic soil dynamic behavior of saturated sands reasonably. It is also found that the critical plastic shear strain can be used as a registible index of soils to represent the critical soil dynamic state, because it seems to include no effect of large deformation.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.140-147
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• 2012

This study was conducted to investigate optimum planting density for apartment complex. The validity of Landscape Architecture Criteria of Korea was checked for it. We compared our field data with Landscape Architecture Criteria. In this step, the tree density of urban forest was regarded as standard. Field study was examined in 3 apartment complexes located in capital area, especially completed during these 10 years. 10 sites in each complex were selected and tree density per unit area were calculated. This field study data was divided standard size and large size which received weight. And, it was compared and analyzed. And crown projected area(CPA) was calculated considering proper growth of low vegetation and sufficient shade. The outcome shows that minimum size of Landscape Architecture Criteria is rational. But, in the case of planting large size tree received weight, tree density was short comparing with the tree density of urban forest and CPA was less than 50%. By the result of field study in 3 apartment complex, the tree density of apartment complex satisfied or exceeded Landscape Architecture Criteria. But, in the case of planting large size tree, tree density and CPA show high density due to addition planting for deficient landscape. Therefore, the revision of the Landscape Architecture Criteria was required such as deletion or minimization of the weighted clause about the large size tree and regulate the limit CPA not less than 50% and not more than 100%.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.64-74
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• 2010

The study is based on an urban park design that is designed in consideration of the characteristics of Uijeongbu City, applied with adequate functions for the environment and showcasing the unique scenery in relation to the relocation of the US Air Force Camp Falling Water. The bases of the design are: the reasonable convergence of the square and park in consideration of the site characteristics; the application of an urban context as the park is located near a station; and the realization of an eco-friendly space. This study is based on foundation research regarding a review of urban square patterns, particular items in planning in relation to modern urban parks and the adaptability of the park in the future. Regarding space usage, the design is applied with notable ideas that allow the space to make its own characteristics through voluntary user activity in conjunction with the environment that will allow the park to cope with changes in the future, as opposed to a space that users experience through pre-determined programs. Below are the focal points of the design. First, the park is designed as an empty space which may accommodate the urban structural context of and usage patterns for being a field of the city ecology that changes and develops, beyond a passively-created square pattern. Such open spaces have a continuity which allows it to adapt to the development of the city. In addition, the design facilitates spontaneous processes through changes in usage pattern and time. Second, the design includes the message that the park and the city, natural things and artificial things, must communicate and network with each other. Hence the park shall not be an isolated green island within the city, but is an open space accommodating the demands for open area from nearby commercial, public and residential facilities; the park shall include a field that can accommodate a variety of programs. Third, the park is designed to encourage the effect of direct and indirect practical education by reflecting a physical plan as well as interesting experience design methods to lower carbon emissions and to create and maintain an eco-friendly space, the basis of a zero-emissions city.

• Progress in Medical Physics
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• v.26 no.1
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• pp.28-35
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• 2015

In this study, we investigated the effects of an iterative reconstruction algorithm and an automatic exposure control (AEC) technique on image quality and radiation dose through phantom experiments with coronary computed tomography (CT) angiography protocols. We scanned the AAPM CT performance phantom using 320 multi-detector-row CT. At the tube voltages of 80, 100, and 120 kVp, the scanning was repeated with two settings of the AEC technique, i.e., with the target standard deviations (SD) values of 33 (the higher tube current) and 44 (the lower tube current). The scanned projection data were reconstructed also in two ways, with the filtered back projection (FBP) and with the iterative reconstruction technique (AIDR-3D). The image quality was evaluated quantitatively with the noise standard deviation, modulation transfer function, and the contrast to noise ratio (CNR). More specifically, we analyzed the influences of selection of a tube voltage and a reconstruction algorithm on tube current modulation and consequently on radiation dose. Reduction of image noise by the iterative reconstruction algorithm compared with the FBP was revealed eminently, especially with the lower tube current protocols, i.e., it was decreased by 46% and 38%, when the AEC was established with the lower dose (the target SD=44) and the higher dose (the target SD=33), respectively. As a side effect of iterative reconstruction, the spatial resolution was decreased by a degree that could not mar the remarkable gains in terms of noise reduction. Consequently, if coronary CT angiogprahy is scanned and reconstructed using both the automatic exposure control and iterative reconstruction techniques, it is anticipated that, in comparison with a conventional acquisition method, image noise can be reduced significantly with slight decrease in spatial resolution, implying clinical advantages of radiation dose reduction, still being faithful to the ALARA principle.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.101-115
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• 2000

This study aims to make a research on the secondary school education of geography and the system of teacher training in Belgium, focused on the case of Francophone Community. What has been made clear by this research can be summed up as follows. The first two years of the secondary school offer two hours of 'environment education', per week, which can be categorized into the learning of living geography, in that at this stage students learn how to observe the geographic phenomena in their daily life and pigeonhole them. The two years of the second stage of the secondary school offer one hour of 'world geography' which actually is focused on the district of Europe and Russia. The two years of the third stage of the secondary school offer an advanced course of geography which aims to teach systematically the physical geography and the human geography. A remarkable change in geographic education in Belgium is that in the wake of the Revision Act of the secondary school education, textbooks were replaced by other teaching manuals adapted to the regional condition by the teachers. This may result in a wide gap of achievements in geography according to the conditions of educational establishments. Another notable change is that the stress of geographic education tends to be placed on the ability of acquiring practical geographic knowledge rather than the geographic information itself. And it is also another marked tendency that most learning activities in geography class are conducted on the basis of student-centered and the method of investigation. Teachers of the lower secondary schools in Belgium are trained in the School of Education as multi-major teachers, such as a teacher for biology-chemistry-geography or a teacher for history-sociology-geography. Teachers of the higher secondary school education are trained in the Department of Teacher Education in universities as solo-major teachers in that they are required to know more deeply to teach an advanced course of geography in the higher secondary schools. To improve the teacher education many folds of policies are adopted. One is that many in-service teachers are officially put into services of guiding and teaching teacher training. Another is that faculty members in charge of teacher training course are trying to level up the qualifications of teachers by rigorous disciplining.

• Journal of Nutrition and Health
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• v.43 no.4
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• pp.404-412
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• 2010

This paper specifically discusses the risk assessment on the pesticide residues in vegetables collected from traditional markets, big marts and departments in the southern part of Seoul. Vegetable samples were 6,583 cases from January to December in 2009. Monte-Carlo simulation was used to calculate the uncertainty for the risk index using pesticide residues, average dietary intake for vegetables and acceptable daily intake. Deterministic risk indexes were 7.33% of diethofencarb, 5.13% of indoxacarb, 3.96% of EPN, 3.92% of diniconazole and 3.09% of chlorothalonil, respectively. And other pesticides were below 3%. Distributions of risk indexes obtained by the Monte-Carlo simulations were similar to the deterministic values, even though the confidence intervals for 95% were very wide. We confirmed that health risks caused by eating vegetables exceeded maximum residue limits of pesticide are very low and the population is generally safe, judging from the risk indexes located between 0.07 to 9.49%.

• Journal of Science Education
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• v.38 no.3
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• pp.718-736
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• 2014

This study was intended to determine PCK of the middle school science teachers on Mendelian genetics and factors influenced to form their PCKs. Two science teachers with biology major with a teaching experience over 5 years were chosen as the subject. Data were collected by class observation, semi-structured interview, teacher questionnaire survey, Content Representation and Pedagogical and Professional-experience Repertoire. The collected data were analyzed based on Magnusson's PCK for science teaching consisting of five components: (a) the orientation toward teaching science, (b) the knowledge of science curriculum, (c) the knowledge of students' understanding, (d) the knowledge of assessment, and (e) the knowledge and belief in the instructional strategies to teach science. Teachers could have the orientation toward teaching science served as an assisting role to support students' abilities. Both subject teachers seemed to focus on giving lectures. Their efforts to improve students' exploration methods and abilities were not expressed enough in their real classes and they found that students struggled to understand Mendelian genetics. Therefore, they should have explained them in an easier way and worked harder to make their students understood accurately and applied basic and advanced concepts of Mendelian genetics. They found students' preconception and misconception regarding Mendelian genetics and wished to enhance their learning effects by various teaching strategies such as correcting misconception, adding the history of science and simply assessing students' affirmative domains. It was also found that factors influenced to form PCK regarding Mendelian genetics by both teachers were as follows: teacher's personality and endeavor, textbooks and guidance books, schools and their circumstances, teaching experience, experience as a learner, interaction with their colleagues, and university curriculum. Both teachers said that it was important for teachers to make every efforts to give better classes.

• The Korean Society of Law and Medicine
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• v.21 no.1
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• pp.107-152
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• 2020

During the main ruling in 2019, a number of rulings that were of interest or meaningful were handed down, such as just because the complication of medical practice has occurred, there is no presumption of negligence, a case involving a fall accident in which a lot of culpability has recently been made. the death of a well-known singer that caused a sensation, a case about damages caused by MERS in 2015, which is more meaningful in connection with damages caused by COVID-19, an infectious disease that has recently hit the world, including Korea. In preaching the principles of the law, just because there has been a complication caused by medical practice, there is no presumption of negligence, 'The scope of the complication without presumption of negligence' was determined differently by the court, the court was not able to specify the criteria. Specific circumstances were presented to limit the responsibility of the medical institution while acknowledging the malpractice of the medical institution in relation to the fall accident. In relation to the scope of damages, judgment was made on issues related to the calculation of lost profits of medical malpractice; criteria for determining celebrities' daily income, criteria for determining daily income in case of receiving survivor's pension due to medical accident, an incident in which the daily income is denied if the labor capacity is already lost at the time of a medical accident. But, it seems that judgments should be made based on clearer and more reasonable standards. Related to Medical Advertise, specific logic of judgment was presented as to whether it was interpreted as being in accordance with the specific prohibition listed in Article 27 paragraph 3 of the Medical Law, which is the criterion for violation of the Medical Law, or if it constitutes a significant harm to the order of the medical market. In response to the prohibition of operating the multiple medical institutions, the Constitutional Court decided that it was constitutional because it did not violate the regulations on excessive funding, and rationally limited the scope of the prohibited 'redundant operation'. The Supreme Court ruled for the first time that even a medical institution established and operated in violation of the Medical Service Act did not make it impossible to receive all medical care benefits implemented by a medical institution under the National Health Insurance Act. Significant rulings were finalized that recognized the existence of specific protection obligations for the people of the country in the management of infectious diseases.

• Journal of Preventive Medicine and Public Health
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• v.26 no.3 s.43
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• pp.457-468
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• 1993

This study was conducted to investigate the repeat test rate for diagnosis at a tertiary hospital for the outpatients who were referred themselves to the hospital by the clinics and other medical facilities. The study population consisted of 498 patients who visited outpatient department of internal medicine, general surgery, orthopedic surgery and neurosurgery in the hospital between March 16 and April 11, 1992. This study was surveyed by the questionnaire about the tests for diagnosis at first level medical facilities, and then, was investigated by the medical record about the tests for diagnosis at a tertiary hospital. The proportion of test among the patients who utilized the first level medical facilities was 20.9% for the X-ray test, 10.6% for the urinalysis, 9.0% for the electrocardiogram, 3.4% for the computer tomogram and 6.4% for the ultrasonogram. At the tertiary hospital, the X-ray test was 45.2%, the liver function test was 24.1%, the urinalysis was 19.1%, and the electrocardiogram was 15.7%. The proportion of patients who possessed results of test for diagnosis at the first level medical facilities was 76.5% for the computer tomogram, and 31.3% for the ultrasonogram. As the repeat test rate between the first level medical facilities and the tertiary hospital, the thyroid function test was the first rank as 71.4%, the second rank was the routine CBC as 67.9%, and the third rank was the X-ray test as 64.4%. But among the patients that brought the result for tests at the first level medical facilities, the repeat test rate was as follow : the routine CBC was 75.0%, the liver function test was 72.1%, and the computer tomogram was 15.4%.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.37-45
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• 1984

This study was conducted to identify the problems in the medical aid program by reviewing the medical care utilization pattern of the beneficiaries. The data were abstracted from the monthly bills and vouchers for medical care of the whole benefi챠aries(17,527) in Gyeongsan Gun submitted by the physicians to county government for the period of 1 calendar year from October 1981 to September 1982. The number of medical aid beneficiary accounted for 12.7% of the total county population, a higher proportion than the national average-9.5%. Monthly primary care utilization rate per 100 beneficiaries was 9.3 persons with 14.0 visits and 42.9 medication days. for the 2nd and 3rd care, there were 1.7 admissions and 9.3 OPD visits per 100 beneficiaries per year. The beneficiaries of the first class medical aid program had a higher utilization rate of both the primary and secondary/tertiary care facilities. Females utilized more the primary care facilities than males while males utilized more the secondary/tertiary care facilities than females. A significantly lower utilization rate was observed in January than in the other months and this was seemed due to the renewal process of the medical aid certificate. Among 1,931 patients utilized the 2nd/3rd care facilities 84.4% was out-patients and the lowest ratios were in the minor specialties including ENT, ophthalmology, dermatology and urology. The average hospital days per in-patient were 21.2 days and OPD days per out patient were 4.7 days. The average hospital days for a psychiatry in-patient was 74.4 days which was the longest average hospital days among all the specialties. Average medical care cost per beneficiary in a year was W9,821:W24,240 for the 1st class and W7,464 for the 2nd class. The medical care cost for the primary care per patient was W3.901 and W840 per day compared with W49,875 per patient and W5,822 per day for the secondary/tertiary care. From the findings of this study following recommendations were made to improve the medical care program: 1) The renewal process of the medical care certificate should be expedited. 2) Minor specialty clinics should be designated as the primary medical care facility for the medical aid program to reduce the expenses by absorbing more patients referred to the secondary/tertiary care facilities directly. 3) The medical care cost for the primary care facility should be escalated to reduce the differential between the primary and secondary/tertiary care facilities.