• Journal of the Earthquake Engineering Society of Korea
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• v.19 no.1
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• pp.21-28
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• 2015

The nuclear accident due to the recent earthquake in Japan has triggered awareness of the importance of safety with regard to nuclear power plants (NPPs). An earthquake is one of the most important parameters which governs the safety of NPPs among external events. Application of a base isolation system for NPPs can reduce the risk for earthquakes. At present, a soil-structure interaction (SSI) analysis is essential in the seismic design of NPPs in consideration of the ground structure interaction. In the seismic analysis of the base-isolated NPP, it is restrictive to consider the nonlinear properties of seismic isolation devices due to the linear analysis of the SSI analysis programs, such as SASSI. Thus, in this study, SSI analyses are performed using an iterative approach considering the material nonlinearity of the isolators. By performing the SSI analysis using an iterative approach, the nonlinear properties of isolators can be considered. The difference between the SSI analysis results without iteration and SSI with iteration using SASSI is noticeable. The results of the SSI analysis using an effective linear (non-iterative) approach underestimate the spectral acceleration because the effective linear model cannot consider the nonlinear properties of isolators. The results of the SSI analysis show that the horizontal response of the base-isolated NPP is significantly reduced.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4A
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• pp.621-637
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• 2006

Although the approaches implementing strut-tie models are the valuable tools for designing discontinuity regions of structural concrete, the approaches of the current design codes have to be improved for the design of structural concrete subjected to complex loading and geometrical conditions because of the uncertainties in the selection of strut-tie model, in the use of an indeterminate strut-tie model, and in the effective strengths of struts and nodal zones. To improve the uncertainties, a grid struttie model approach is proposed in this study. The proposed approach, allowing to perform a consistent and effective design of structural concrete, employs an initial grid strut-tie model in which various load combinations can be considered. In addition, the approach performs an automatic selection of an optimal strut-tie model by evaluating the capacities of struts and ties using a simple optimization algorithm. The validity and effectiveness of the proposed approach is verified by conducting the analysis of the four reinforced concrete deep beams tested to failure and the design of shearwalls with two openings.

• Journal of the Korean Society for Railway
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• v.16 no.5
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• pp.439-446
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• 2013

The market taxonomy approach may lead to the most effective strategy to promote the export of Korean Railway Systems. By prioritizing opportunities in the global marketplace and subsequently identifying market segments, this approach will reveal the most effective market strategies for Korean rail exporters. This study suggests the market potential index. In addition, it also introduces how market segmentation should be done for the global rail supply market. Applying the market taxonomy to derive strategic implications, this study portrays several export projects currently being undertaken by the Korean rail industry.

• Journal of Internet Computing and Services
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• v.18 no.3
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• pp.49-61
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• 2017

Wikipedia infoboxes have emerged as an important structured information source on the web. To compose infobox for an article, considerable amount of manual effort is required from an author. Due to this manual involvement, infobox suffers from inconsistency, data heterogeneity, incompleteness, schema drift etc. Prior works attempted to solve those problems by generating infobox automatically based on the corresponding article text. However, there are many articles in Wikipedia that do not have enough text content to generate infobox. In this paper, we present an automated approach to generate infobox for movie domain of Wikipedia by extracting information from several sources of the web instead of relying on article text only. The proposed methodology has been developed using semantic relations of article content and available semi-structured information of the web. It processes the article text through some classification processes to identify the template from the large pool of template list. Finally, it extracts the information for the corresponding template attributes from web and thus generates infobox. Through a comprehensive experimental evaluation the proposed scheme was demonstrated as an effective and efficient approach to generate Wikipedia infobox.

• The Korean Journal of Pain
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• v.10 no.1
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• pp.89-92
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• 1997

Neurolytic splanchnic nerve block is effective for treatment of intractable upper abdominal cancer pain. Conventional approach for splanchnic nerve block is conducted in the prone position to ensure proper orientation and to allow insertion of needles on each side of the vertebral body. However, the prone position has some technical disadvantages as this position is frequently poorly tolerated by a majority of patients with advanced cancer due to severe abdominal pain, ascites and so on. Male patient, 53-year old with transverse colon cancer, carcinomatosis peritonei and $L_1,\;L_2$ vertebral body metastasis, was admitted for treatment of severe right upper quadrant and right iliac crest pain. We performed neurolytic splanchnic nerve block with transdiscal technique in the lateral decubitus position under fluoroscopic guidance, and well noted the usefulness and the advantage of this technique. The benefits of this technique are safe, simple and effective because the lateral position is better tolerated by patients and makes bony landmarks more accessible during fluoroscopy.

• Computers and Concrete
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• v.5 no.4
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• pp.375-388
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• 2008

Crack opening governs many transfer properties that play a pivotal role in durability analyses. Instead of trying to combine continuum and discrete models in computational analyses, it would be attractive to derive from the continuum approach an estimate of crack opening, without considering the explicit description of a discontinuous displacement field in the computational model. This is the prime objective of this contribution. The derivation is based on the comparison between two continuous variables: the distribution if the effective non local strain that controls damage and an analytical distribution of the effective non local variable that derives from a strong discontinuity analysis. Close to complete failure, these distributions should be very close to each other. Their comparison provides two quantities: the displacement jump across the crack [U] and the distance between the two profiles. This distance is an error indicator defining how close the damage distribution is from that corresponding to a crack surrounded by a fracture process zone. It may subsequently serve in continuous/discrete models in order to define the threshold below which the continuum approach is close enough to the discrete one in order to switch descriptions. The estimation of the crack opening is illustrated on a one-dimensional example and the error between the profiles issued from discontinuous and FE analyses is found to be of a few percents close to complete failure.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.3
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• pp.23-30
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• 2003

The seismic base isolation design approach has been reviewed and modified to fit the nonlinear static analysis procedure for determination of the performance point of structures in a simpler way, such an adaptation may be possible for the fact that a structural system under development of damage due to earthquake loading keeps softening to result in period shifting toward longer side. The superiority of the proposed method to the state-of-the-practice approach is that the reasonably accurate performance point can be obtained without constructing the so-called acceleration displacement response spectrum required in application of capacity spectrum method. The validity of the proposed approach was verified by comparing the predicted values to the exact ones presented in the literature.

• Clinical and Experimental Pediatrics
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• v.53 no.9
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• pp.830-833
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• 2010

Crohn's disease is characterized by chronic inflammation involving any portion of the gastrointestinal tract. Treating Crohn's disease is a major challenge for clinicians, as no curative therapy currently exists. Pediatric Crohn's disease is characterized by frequent relapses, a wide extent of disease, a high prevalence of extraintestinal manifestations, and a severe clinical course. The classic therapeutic approach is known as the 'step-up' strategy, and follows a progressive course of treatment intensification as disease severity increases. Although this approach is usually effective for symptom control, many patients become either resistant to or dependent on corticosteroids. The efficacy of infliximab suggests that, rather than a progressive course of treatment, early intense induction may reduce complications associated with conventional treatment and improve quality of life. Intensive early therapy with infliximab is known as the 'top-down' strategy. Such therapy offers the potential for altering the natural history of Crohn's disease, and is changing treatment paradigms. However, the relatively new concept of an early aggressive or 'top-down' treatment approach is not yet widely accepted, especially in pediatric patients. The results of our current study demonstrate that early and intensive treatment of pediatric Crohn's disease patients with infliximab, at initial diagnosis, was more effective for maintaining remission and reducing flares.

• Structural Engineering and Mechanics
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• v.52 no.3
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• pp.633-646
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• 2014

A semi-analytical numerical approach for the effective structural dynamic response analysis of spar floating substructure for offshore wind turbine subject to wave-induced excitation is introduced in this paper. The wave-induced rigid body motions at the center of mass are analytically solved using the dynamic equations of rigid ship motion. After that, the flexible structural dynamic responses of spar floating substructure for offshore wind turbine are numerically analyzed by letting the analytically derived rigid body motions be the external dynamic loading. Restricted to one-dimensional sinusoidal wave excitation at sea state 3, pitch and heave motions are considered. Through the numerical experiments, the time responses of heave and pitch motions are solved and the wave-induced dynamic displacement and effective stress of flexible floating substructure are investigated. The hydrodynamic interaction between wave and structure is modeled by means of added mass and wave damping, and its modeling accuracy is verified from the comparison of natural frequencies obtained by experiment with a 1/100 scale model.

• Journal of the Korean Geotechnical Society
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• v.19 no.3
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• pp.75-82
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• 2003

This paper presents the results of a study that was performed to evaluate fronds of shear strength parameters in stabilization of unbound soil-aggregate systems based on the theory of unsaturated soil mechanics. Two important shear strength parameters, effective cohesion and effective angle of internal friction were estimated by the proposed approach using the results from suction measurements and unconfined compressive strength test. In addition, the effect of different addition rates of stabilizing agent was compared. Due to the stabilization process, an increase in suction potential on engineering properties of geomaterials was observed by using dielectric constant measurements. In conclusion, the results from this study show that the proposed approach can be simply used for predicting shear strength parameters of the stabilized geomaterials.