• Magazine of the Korea Concrete Institute
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• v.11 no.1
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• pp.149-160
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• 1999

This paper is a part of a research aimed at the verification of basic design rules of high-strength concrete columns. A total of 32 column specimens were tested to investigate structural behavior and strength of eccentrically loaded reinforced concrete tied columns. Main variables included in this test program were concrete compressive strength. steel amount, eccentricity, and slenderness ratio. The concrete compressive strength varied from 356 kg/$cm^2$ to 951 kg/$cm^2$ and the longitudinal steel ratios were between 1.13 % and 5.51 %. Test results of column sectional strength are compared with the results of analyses by ACI rectangular stress block, trapezoidal stress block, and modified rectangular stress block. Axial force-moment-curvature analysis is also performed for predicting axial load-moment strength and compared with the test results. The ACI rectangular stress block provides over-estimated column strengths for the lightly reinforced high strength column specimens. The calculated strengths by moment-curvature analyses are highly affected by $k_3$ values of the concrete stress-strain curve. Observed failure mode. concrete ultimate strain, and stress block parameters are discussed.

• Korean journal of communication and information
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• v.27
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• pp.283-316
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• 2004

This study examines different news frames of local newspapers reporting the controversial 'Nu[lear Waste Site' issues which deeply split regions showing their intention to bid for the state affair. Three local papers were analyzed for this study, "Gwang-Ju-Il-bo" "Mae-il-sin-mun" and "Jun-buk-il-bo." Overall, the three local papers displayed widely divergent main news frames on the same issue. Firstly, "Gwang-Ju-Il-bo", and "Mae-il-sln-mun" showed the strong tendency of using 'counter frame' while "Jun-buk-il-bo" exhibited 'loral development frame'. Secondly, "Gwang-Ju-Il-bo", and "Mae-il-sin-mun" were frequently headlined 'Nuclear Waste Site', while "Jun-buk-il-bo" carried headlines 'Radioactive Waste Management Facility' overwhelmingly more often than the other two papers, indicating that headline key words are closely associated with the configuration of news frames. Thirdly, the main news frames remained consistent for "Gwang-Ju-Il-bo", and "Mae-il-sin-mun" even after the government's report about the possible connection of 'ion-beam irradiation-accelator' and 'Nuclear Waste Site.' On the other hand, "Jun-buk-il-bo" was significantly less headlined 'Nuclear Waste Site' while significantly more headlined "Radioactice Waste Management Facility." "Jun-Buk-il-bo" which is in stark contrast to the other two papers changed in its tone by increasing the 'local development frame' with decrease in the 'counter frame.' The "Jun-buk-il-bo"'s more frequent use of 'Radioactive Waste Management Facility' as a headline than "Nuclear Waste Management Equipment" is seen as its attempt to minimize negative image of Nuclear Waste and to promote favorable public opinion by highlighting aspects of economic benefits and the local development the construction would brind about. The major findings of this study further support the claim that media overage ends up a reality. The fact that Buan in Jun-buk Province made a successful bid for the construction is not a coincidence.

• Journal of the Korea Concrete Institute
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• v.25 no.6
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• pp.631-639
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• 2013

Non-linear finite element analysis for newly developed precast concrete details for beam-to-column connection which can be used in moderate seismic region was carried out in this study. Developed precast system is based on composite structure and which have steel tube in column and steel plate in beam. Improving cracking strength of joint under reversed cyclic loading, joint area was casted with ECC (Engineering Cementitious Composites). Since this newly developed precast system have complex sectional properties and newly developed material, new analysis method should be developed. Using embedded elements and models of non-linear finite element analysis program ABAQUS previously tested specimens were successfully analyzed. Analysis results show comparatively accurate and conservative prediction. Using finite element model, effect of axial load magnitude and flexural strength ratio were investigated. Developed connection have optimized performance under axial load of 10~20% of compressive strength of column. Plastic hinge was successfully developed with flexural strength ratio greater than 1.2.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.33-38
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• 2013

Occlusal plane is a sagittal expression of dental arch form, and it composes the shape of occlusion, which is one of the most important elements of Maxillo-oral system. In this case, vertical, horizontal coordinates of bionic-median-sagittal plane was produced in articulator, and to achieve relation of left and right position of upper, lower teeth and deficits in alveola, Shilla system was used to reconstruct occlusal plane. In this case, a 41 year-old male patient visited for fracture of 10 unit metal-ceramic fixed partial denture of upper anterior teeth and for overall treatment. Clinical, radiographical, model examination was held, full mouth rehabilitation was achieved by placing dental implant. Maxillo-oral relation was recorded using Gothic arch Tracer complex and were mounted. And for the next step, we estimated original occlusal plane using Shilla system. After analysis we produced diagnosis wax pattern. On the basis of this, radiography stent was manufactured and dental implant was placed, and temporary prosthesis was made by using diagnosis wax pattern. Cross mounting and anterior guiding table were performed in order to reproduce temporary restoration morphology and bite pattern, followed by final restoration made of all ceramic crown with zirconia coping. As stated above, appropriately esthetic and functional results can be seen in using Shilla system in diagnosis and treatment procedure of full mouth rehabilitation patient.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.355-362
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• 2001

Data derived from odontometric studies are useful in many areas. Especially crown diameter of primary teeth is important in not only anthropology but also clinical dentistry. The purposes of this study were to compare diameters of primary molars of Korean children with those of preformed stainless steel crown, and examine racial characteristics of primary molars of Korean children. The mesiodistal and buccolingual diameters of primary molars were measured on dental casts taken from 235 children(male 105, female 131), with digital calipers. And the data were compared with those of preformed stainless steel crowns. The results were as follows; 1. No significant difference was observed between the right and left members of antimeric teeth and all primary molars of male were larger than those of female. 2. The diameters of primary molars of Korean are smaller than those of Austrailian aborigines and there was significant difference between diameters of primary molars of Korean and those of other populations. 3. There were size differences between diameters of maxillary, mandibular first molar and preformed stainless steel crown than other primary molars, relatively.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.646-651
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• 2009

In this study, it was intended to prepare a stem volume table (with or without bark) and a stand yield table for Juglans mandshurica, plantations in Chungju, located in Chungcheongbuk-do, Korea. For the calculation of stem volume, we applied Kozak's growth model, which showed the best fitness index (97%). With this model, it was able to prepare the first yield table for Juglans mandshurica in Korea. Site index model, an indicator of forest productivity, was derived by using the Chapman-Richard model, in which the basic stand age was set to 30 years. The resulted site index ranged between 16 and 22. Based on the yield table of Juglans mandshurica resulted from this study, the volume for a 70-year-old stand with a midium site index class was estimated to be $238m^3/ha$, which is $100m^3/ha$ higher than the volume estimated from the yield table of Quercus acutissima. The yield table of oak trees has been used in the estimation of most broadleaf stands in Korea. However, the result of this study indicated that it is necessary to generate a stand yield table for each broadleaf species. The annual $CO_2$ removals of 30-year-old Juglans mandshurica plantations in the ChungJu region was estimated to be $5.84tCO_2/ha$. The stem volume and stand yield table of Juglans mandshurica plantation resulted from this study would provide a good information in decision making for forest management in ChungJu region.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1153-1163
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• 2013

Bonded concrete overlay is a favorable maintenance method since the material properties are similar to existing concrete pavements. In addition, bonded concrete overlay has advantage of structural performance based on being bonded together, both for the overlay layer and the existing pavement which perform as one monolithic layer. Therefore, it is important to have a suitable bond strength criteria for long term performance of bonded concrete overlay. This study aimed to investigate the affecting of bond strength on various bond characteristics, and to compare the bond strength between direct tensile test and indirect tensile test due to various conditions such as overlay materials, compressive and flexure strength of existing pavement, and deterioration status of existing pavement. As a result of this study, bond strength occurred by both of direct and indirect tensile test due to monotonic load is highly correlated such as coefficient of determination of 0.75 and P-value of 0.002. However, bond strength by indirect tensile test was relatively higher than bond strength by direct tensile test. It was known that correlation between direct and indirect tensile test was possible to use the characteristics analysis of bond fatigue behavior based on bond strength due to cyclic load which can simulate real field behavior of bonded concrete overlay.

• Journal of Distribution Research
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• v.16 no.5
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• pp.123-140
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• 2011

This study analyzed large distributors' trade features with local suppliers and their direct purchase features through the survey and the interview targeting some MDs(Merchandisers) in large retailers responsible for buying fresh foods (agricultural, fishery, livestock and proceeded products). As the result of conducting the survey targeting the large purchase MDs, it was found that when they select local suppliers, they importantly consider the factors of stable products supply, the quality management, the aggressive management attitude, the affordable (cheap) price, and the suggestion of differentiated goods in order. Concerning their direct purchases in local places, their preference toward the direct-purchase traders were higher than that toward vendors and whole markets as their existing major traders. Among the traders for direct purchase, they preferred farm corporations (including agricultural corporations) the most, and followed the National Agricultural Cooperative, and the unit agricultural cooperative in order. Regarding to the trades with suppliers, when they set the trade price, the merchandisers (MDs) of large distributors preferred long-term trades over 2 years, and utilized the factors of market rate(50.9%), production cost(31.2%) and sale price in the same industry(18.0%). For the local distribution organizations to aggressively counteract the changes of distribution environment in the consumption places, it needs some strategies to organize the agricultural production, to expand the production size and to specialize the distribution channels. And the supply system's continuality and stability are required, so it needs to establish the counteract system enabling to supply all year round through the link of production organizations. Additionally, as an effort to intensify the market negotiation ability, it should collect various market information from the consumption places.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.739-744
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• 2017

Elastic deformation and fatigue damage can cause the permanent deformation of a kart's frame during turning, affecting the kart's driving performance. A kart's frame does not contain any suspension or differential devices and, therefore, the dynamic behavior caused by torsional deformation when driving along a curve can strongly affect these two kinds of deformations. To analyze the dynamic behavior of a kart along a curved section, the GPS trajectory of the kart is obtained and the torsional stress acting on the kart-frame is measured in real time. The mechanical properties of leisure and racing karts are investigated by analyzing their material properties and conducting a tensile test. The torsional stress concentration and frame distortion are investigated through a stress analysis of the frame on the basis of the obtained results. Leisure and racing karts are tested in each driving condition using driving analysis equipment. The behavior of a kart when being driven along a curved section is investigated through this test. Because load movement occurs owing to centrifugal force when driving along a curve, torsional stress acts on the kart's steel frame. In the case of a leisure kart, the maximum torsional stress derived from the torsional fatigue limit was found to be 230 MPa, and the torsional fatigue limit coefficient was 0.65 when driving at a speed of 40 km/h. Furthermore, the driving elements during the cornering of a kart were measured based on an actual auto-test after installing a driving measurement system, and the driving behavior of the kart was analyzed by measuring its vertical displacement.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.722-729
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• 2010

Prediction problems are widely used in medical domains. For example, computer aided diagnosis or prognosis is a key component in a CDSS (Clinical Decision Support System). SVMs with nonlinear kernels like RBF kernels, have shown superior accuracy in prediction problems. However, they are not preferred by physicians for medical prediction problems because nonlinear SVMs are difficult to visualize, thus it is hard to provide intuitive interpretation of prediction results to physicians. Nomogram was proposed to visualize SVM classification models. However, it cannot visualize nonlinear SVM models. Localized Radial Basis Function (LRBF) was proposed which shows comparable accuracy as the RBF kernel while the LRBF kernel is easier to interpret since it can be linearly decomposed. This paper presents a new tool named VRIFA, which integrates the nomogram and LRBF kernel to provide users with an interactive visualization of nonlinear SVM models, VRIFA visualizes the internal structure of nonlinear SVM models showing the effect of each feature, the magnitude of the effect, and the change at the prediction output. VRIFA also performs nomogram-based feature selection while training a model in order to remove noise or redundant features and improve the prediction accuracy. The area under the ROC curve (AUC) can be used to evaluate the prediction result when the data set is highly imbalanced. The tool can be used by biomedical researchers for computer-aided diagnosis and risk factor analysis for diseases.