• KIEE International Transactions on Power Engineering
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• v.12A no.1
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• pp.6-14
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• 2002

In this paper, an EMM(Equivalent Mechanical Model) Is developed to explain the voltage collapse mechanism by reflecting the effects of reactive powers. The proposed EMM exactly represents the voltage instability mechanism described by the system equations. By the use of the EMM model, the voltage collapse mechanism has been illustrated by showing the exactness of the results. The stable region has been investigated with a reactive-power-controlled two-bus system, which shows that special alerts are required when the system operates with leading power factor. It is also discussed a system transform technique to eliminate the resistance component of the Thevenin equivalent impedance for practical applications. Finally, the results adopting the proposed method fur sample systems which were transformed are listed

• Korean Institute of Interior Design Journal
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• v.16 no.6
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• pp.172-180
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• 2007

As library have become changed. Beyond conventional simple functions such as data storing and recording, the functions of modern public libraries are expended to various directions, for example functions of encouraging residents to utilize information and participate in cultural activities and also a function of life-long education, resulting in playing a role as complex space. As the role of public libraries changes into a complex one, spatial planning reflecting this change is required. Spatial arrangements, furniture arrangements and interior images in 12 public libraries in Seoul were analyzed. As a result of the study, it was found that in spatial arrangements, many public libraries linked spaces by functions. Furniture arrangements have been changing from the closed arrangement to the open arrangement. Interior images were identified as static and simple except digital information space. Accordingly, public libraries have became needed to play a proper role of community facilities for local residents by planning furniture arrangements and conducting interior designs taking characteristics of many different users into consideration.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.225-228
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• 2008

There are many studies about submerged structures or porous wave absorbers to decrease damage of coast and structures. Submerged structures and porous wave absorber are decreasing energy of incoming wave by reflecting or dissipation with changing depth or with porous rubble mound. This study addresses the reflection and transmission of long wave from a trapezoidal breakwater and a vertical porous wave absorber at the same time. A systematic shape transfer is derived to determine wave reflection and transmission. And periodic solutions are matched at the slope and the front face of the absorber by assuming continuity of pressure and mass. The transmission coefficient is determined as a function of parameters describing the incoming waves, transmitting waves through the trapezoidal breakwater and the absorber characteristics.

• Tunnel and Underground Space
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• v.6 no.1
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• pp.30-38
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• 1996

A two dimensional analysis program for groundwater flow in fractured network was developed to analyze the influence of discontinuity characteristics on groundwater flow. This program involves the generation of discontinuities and also connectivity analysis. The discontinuities were generated by the probabilistic density function(P.D.F.) reflecting the characteristics of discontinuities. And the fracture network model was completed through the connectivity analysis. This program also involves the analysis of groundwater flow through the discontinuity network. The result of numerical experiment shows that the equivalent hydraulic conductivity increased and became closer to isotropic as the density and trace length increased. And hydraulic head decreased along the fracture zone because of much water-flow. The grouting increased the groundwater head around cavern. An analysis of groundwater flow through discontinuity network was performed around underground oil storage cavern which is now under construction. The probabilistic density functions(P.D.F) were obtained from the investigation of the discontinuity trace map. When the anisotropic hydraulic conductivity is used, the flow rate into the cavern was below the acceptable value to maintain the hydraulic containment. But when the isotropic hydraulic conductivity is used, the flow rate was above the acceptable value.

• Nuclear Engineering and Technology
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• v.23 no.1
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• pp.12-19
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• 1991

An engineering approach for estimating the stress intensity factors of a semi-elliptical crack is presented. An approximate 2-dimensional approach solution for semi-elliptical crack is derived in terms of simple equation, through weight function technique, by reflecting on the physical character of cracks.

• 중국학논총
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• no.70
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• pp.87-108
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• 2021

This paper makes a comparative analysis of and (Third Edition) textbook. In the introduction part, it puts forward the purpose, significance and research object of the text, combs the general situation of the research on the arrangement of business Chinese textbook, discusses the concept and characteristics of business Chinese, and then makes a detailed comparative analysis of and Two Business Textbooks for Korean and Chinese. Firstly, the paper compares the compiling principles, compiling purposes and applicable objects. Then, it compares the text content, vocabulary selection, grammar teaching, culture and other aspects. Business Chinese has more international teaching ideas and diversified teaching methods in textbook editing, while the former is more targeted in different countries, reflecting more contents of cultural comparison between China and Korea in textbook content. we hope to find a reasonable plan for the compilation of Korean business Chinese textbooks.

• Proceedings of the Korea Water Resources Association Conference
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• 2001.05b
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• pp.1133-1138
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• 2001

The focus of this paper is on the numerical investigation of obliquely incident wane interactions with a system composed of full submerged and floating dual buoy/vertical-flexible-membrane breakwaters placed in parallel with spacing. The fully submerged systems allow surface and bottom clearances to enable wave transmission over and under the system. The problem is formulated based on the two-dimensional multi-domain hydro-elastic linear wave-body interaction theory. The hydrodynamic interaction of oblique incident waves with the combination of the rigid and flexible bodies was solved by the distribution of the simple sources (modified Bessel function of fille second kind) tat satisfy the Helmholz governing equation. Using this computer program, the performance of various dual systems varying buoy radiuses and drafts, membrane lengths, clearances. spacing, mooring-lines stiffness, mooring types, water depth, and wave characteristics is thoroughly examined. It is found that the fully submerged and floating dual buoy/membrane breakwaters call, if it is properly tuned to the coming waves, have good performances ill reflecting the obliquely incident waves over a tilde range of wave frequency and headings.

• Journal of Environmental Science International
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• v.32 no.2
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• pp.89-97
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• 2023

The purpose of this study is to examine the possibilities of use as a factor of the water landscape in modern urban spaces such as parks and, apartments, through a case study of the concept, functions, and culture of moats in the East and West from ancient times to the Middle Ages. This study aimed to examine the concept, origin, and function of the moat as a theoretical consideration. Asian castles with moats, including those in Korea, China and Japan, and Western castles with moats in Britain, France, Belgium, and Germany were investigated and analyzed. By reflecting on these cultures and the functions of the moat in modern urban spaces and converting the environment damaged due to industrialization and urbanization into an eco-friendly and environment symbiotic city the quality of life can be improved, and sustainable development can be achieved. This study was conducted through a literature survey and field investigation.

• Childhood Kidney Diseases
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• v.27 no.2
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• pp.55-63
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• 2023

In 2021, a new chapter on the general management of glomerulonephritis (GN) was added to the Kidney Disease: Improving Global Outcomes (KDIGO). It emphasizes the importance of early general management of GN for improving long-term kidney outcomes and prognosis. The chapter introduces the management of glomerular diseases in 18 subchapters. Here, kidney biopsy for the diagnosis and evaluation of kidney function and the management of complications, such as hypertension, infection, and thrombosis, are presented. Moreover, the adverse effects of glucocorticoids and immunosuppressive therapy, which are commonly used drugs for glomerular disease, are mentioned, and a guideline for drug selection is presented. Each subtheme focused on items reflecting the interpretation of the "practice points" of the expert working group are introduced. In this review of the general treatment for GN in the KDIGO guidelines, excluding pregnancy and reproductive health, we focused on and compared various references pertaining to pediatric GN management.

• Korea Trade Review
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• v.46 no.4
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• pp.219-234
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• 2021

Armington elasticity has been a methodology for analyzing how much imports could increase in response to importing price cuts, assuming the possibility of incomplete substitution of domestic and imported products. This study calculates Armington elasticity values in Korean fisheries sector and presents an analysis method for classifying items based on price and preference differences. The model is modified reflecting the characteristics of the fisheries market along with the typical OLS, PAM, and ECM models. The result's implication is that products with a high import growth rate do not necessarily show a high Armington value, but it could be seen that price is not the only factor facilitating fisheries imports increase. Considering the items of which demand increases due to importing price cuts have an indiscriminate demand between domestic and imported products, the results could be interpreted that the Korean fisheries importing market has been easily affected by the changes in import prices. Fisheries grouping by price and preference demonstrates that explanatory variables other than price should be considered when estimating import demand.