• 천문학회보
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• 제42권1호
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• pp.56.1-56.1
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• 2017

When turbulent motions perturb magnetic field lines and produce magnetic fluctuations, the perturbations leave imprints of turbulence statistics on magnetic field. Observation of synchrotron radiation is one of the easiest ways to study turbulent magnetic field. Therefore, we study statistical properties of synchrotron polarization emitted from media with magnetohydrodynamic (MHD) turbulence, using both synthetic and MHD turbulence simulation data. First, we obtain the spatial spectrum and its derivative with respect to wavelength of synchrotron polarization arising from both synchrotron radiation and Faraday rotation. The study of spatial spectrum shows how the spectrum is affected by Faraday rotation and how we can recover the statistics of underlying turbulent magnetic field as well as turbulent density of electrons from interferometric observations that incorporate the effects of noise and finite telescopic beam size. Second, we study quadrupole ratio to quantitatively describe the degree of anisotropy introduced by magnetic field in the presence of MHD turbulence. We consider the case that the synchrotron emission and Faraday rotation are spatially separated, as well as the situation that the sources of the synchrotron radiation and thermal electrons causing Faraday rotation exist in the same region. In this study, we demonstrate that the spectrum and quadrupole ratio of synchrotron polarization can be very informative tools to get detailed information about the statistical properties of MHD turbulence from radio observations of diffuse synchrotron polarization.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.497-504
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• 1999

This study presents the physical and engineering characteristics of soil-bentonite admixed liner in I landfill. Main focus was the hydraulic conductivity of compacted soil-bentonite admixed and mechanisms governing low permeable properties of the admixed liner. Laboratory and field tests such as compaction, hydraulic conductivity, density, water content for the soil-bentonite admixed liner were carried out. Quality control criteria for the best construction of the soil-bentonite admixed liner was suggested through laboratory and field test results.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.188-190
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• 2001

This study presents procedures and analysis methods for well known two field soil permeability tests, disc-tension infiltrometer and Guelph permeameter. Some case tests are demonstrated and then some problems involving the tests were clarified. This study may be helpful for practical field hydrogeologists.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1990년도 PROCEEDINGS OF THE FIRST KOREA-JAPAN JOINT GEOTECHNICAL SEMINAR ON EXCAVATION and TUNNELING IN URBAN AREAS
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• pp.163-175
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• 1990

A main factor in the design of excavation in an urban area is the movements. The finite element method provides rational predictions of excavation behaviour, yet practical engineers may find difficulties in applying it to the actual field case. In this study, factors affecting the excavation behaviour are considered in details and the applicability of the finite element method to the actual field excavation cases is presented. Numerical examples are analyzed to provide results of parametric study on the affecting factors.

• Journal of Advanced Marine Engineering and Technology
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• 제27권7호
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• pp.826-831
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• 2003

The purpose of this study was to measure the surface tension of hard water through electro-magnetic field for investigating the effect of electro-magnetic water treatment. The maximum reduction of surface tension was 8% comparing to the no treatment case. When the flow velocity through the permanent magnetic device (PMD) was 6.3 m/s, sample of hard water had the minimum surface tension.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 추계 학술대회논문집
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• pp.139-143
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• 2003

In this study the numerical analyses on cavity flow in supersonic flow field are conducted. According to the length-to-depth ratio of cavity, the shear layer is changed, consequently influencing on vortex structure inside the cavity. Especially in case the fluid flow outside cavity impinges inside the cavity, the oscillation of the cavity flow is identified. Another result is that though the cavity flow shows the unsteadiness, characteristics of cavity flow can be represented by pressure coefficients converged.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.533-540
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• 2002

Recently, geogrid reinforcement has been applied tn the subgrade of the roadway and the railway on the compressible layered soil, and the relevant reserch on the reinforcing mechanism has been performed. In this study, mechanics of geogrid reinforcement and the parameters for the improvement of bearing capacity are evaluated and presented based on the case histories of the field load test on the geogrid-reinforced layered subgrade

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.198-203
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• 1998

This study, a sub-one of comprehensive research works titled under “Rural Resources Evaluation System”, tried to verify utility/applicability of the developed model system through the case study works on 3 sample villages, Backya, Uyan and Suyu, representing the lowland, upland and seashore villages respectively. From the various surveying and collecting works including the official/statistical data collection, map analysis, insitu investigation, field survey and written material review, the original data set were obtained and manipulated into final input data for resources grading. After then, by the automatized calculation procedure of “Rural Resources Evaluation System”, score results for resources evaluation were finally produced with the total maximum score being 1,000. Through comparing works among score results of 3 case villages and between score results and areal characteristics of each case village, the applicability of the system developed in this study was well confirmed.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.682-685
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• 2009

Several studies are being carried out to develop the reliable methods for the gas hydrate resource evaluation around the world. In this study, some case studies and investigations on the resource assesment of several advanced research teams were tried and then detail information on the evaluation scheme and technology of each team and nation are explained and analyzed for the future study and development. On top of that, main concepts and major parameters which can affect the quantity of assessment are examined and arranged for applying to our Donghae gas hydrate field case. Finally, the major concepts and methodology for this evaluation are brought forth and a schematic diagram for the main steps are come up with as well.

• 대한가정학회지
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• 제48권5호
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• pp.129-143
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• 2010

In order to improve the quality of student teachers' practicum, this study analysed the current situation of student teachers' field practice in child care centers. The study also assessed the practicum implementation case of H Cyber University. First, this research examined the characteristics of practicum implementation in universities. Second, a variety of strategies based on a blended model, on/off-line lectures, professor-student interaction, university-daycare centers collaboration, e-mentoring, and student teachers' portfolios that reduce the problems of student teachers' training, were explored. Finally, the practicum implementation case that adopted these factors was assessed. The results from this case study implied that student teachers' practicums based on a blended model can be an alternative method for problem-solving in existing student teachers' training in universities.