• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.557-567
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• 2007

In underground parking lots of apartment housing, the story height is increased by $300{\sim}400mm$ because of various ducts for HVAC. In order to reduce this story height, this study proposed the 'hybrid beam', which is composed of PC beam with embedded steel beam and insitu concrete. The depth of the hybrid beam is reduced by 300 mm and then the steel beam is embedded over the length of reduced depth to compensate for the loss of strength. Then, we performed the large-scale structural tests on 9 specimens and investigated the flexural behavior of the specimens. The parameters of tests were the shape of steel beam section, the length of the reduced depth, the stage of construction, the effects of slab and shear connectors. The test results showed that the specimens, after the insitu concrete has cured, has the flexural capacity which exceeds the required design capacity regardless of other parameters. On the other hand, the specimens of construction stage do not have sufficient strength. Based on these results, it is thought that the proposed hybrid beam with reduced depth is applicable to the underground parking lots of apartment housing as long as the support is placed at construction stage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.557-566
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• 2018

Shopping malls have been developed to increase sales revenue and attract visitors. This study focused on the sense of the outdoor characteristics of these shopping malls by comparing open and enclosed types of shopping malls in common spaces in LA and Korea through case study analyses. This research through case studies will form the foundation of comfortable shopping mall space design. The results are the follows. 1. Enclosed shopping malls tend to provide large indoor space to create a sense of outdoors. 2. The common space of enclosed shopping malls is developed through space expansion with horizontal and vertical connections that appear in different combinations depending on the space constraints and contexts. 3. The architectural planning of enclosed shopping malls are largely dependent on the concept of everyday life portrayed in the identity of each space, which usually involve the inclusion of sizable atriums to host indoor sports or special performances.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.683-692
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• 2020

A joint displacement resistance evaluation method for selecting waterproofing materials in railway bridge decks is proposed. The displacement range for an evaluation is determined by finite element method (FEM) analysis of a load case based on an existing high-speed PSC Girder Box railroad bridge structure. The FEM analysis results were used to calculate the minimum joint displacement range to be applied during testing (approximately 1.5 mm). For the evaluation, four commonly used waterproofing membrane types, cementitious slurry coating (CSC), polyurethane coating system (PCS), self-adhesive asphalt sheet (SAS), and composite asphalt sheet (CAS), were tested, with five specimens of each membrane type. The joint displacement width range conditions, including the minimum displacement range obtained from FEM analysis, were set to be the incrementing interval, from 1.5, 3.0, 4.5, and 6.0 mm. The proposal for the evaluation criteria and the specimen test results demonstrated how the evaluation method is important for the sustainability of high-speed railway bridges.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.2
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• pp.109-109
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• 2000

This study seeks what kind of factors influence to locate dwellings and to establish scenic spots in nature by a case study focused on a meandering stream. The study specially concentrates on the interrelationship between both residences and beautiful sceneries and a meander cut-off-area that reveals a special topographical characteristics, located at Samji village in Youngyang-eup, Youngyang-gun, Koungsangbuk-do. The meander cut-off area, developed at the middle or upper reaches of a river, often makes up specific landscapes such as precipitous cliffs, sheer cliffs and caves. And the area where is specially created by sudden change of flow due to erosion perceived by the cut surface to be the most beautiful scenic spot. These beautiful landscapes were used to be called as Dae, Dam or Gul and managed by Confucian scholars who enjoy refined taste and devote themselves to the study in nature. Moreover, the Ku-Hado-literary means the area of ex-flow-made the scholars' lving with a well prepared basis for agriculture where supplied a cornucopia of organic matters and water. The merit of agriculture made it possible that the scholars became economically independent, and the fact might be the essential point why the meander cut-off area took noticed. Actually, Cho-family has been in Smaji Village for generations, producing a large number of scholars and keeping the actual power of the region. The physical shape of the meander cut-off area, cozily surrounded by mountains, is considered as a good place for the dwelling due to the influence of traditional sight of view for location and P'ungsuchiri which is known as Feng Shui in China and geomancy in the western world. It is a fruit in it own way that we could find the ancestors' discernment and wisdom from this study, who have lived their lives adapting themselves to the given natural environment and also utilizing the nature wisely. But this is a current-argued study on the meander cut-off area. Follow-up studies have to be continued about the landscapes of the meander streams and the meander cut-off areas scattered all over the country except Samji Village and draw the characteristics from the comparative analysis.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.8
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• pp.621-630
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• 2018

In the case of launch vehicles using liquid fuel, natural frequency changes due to fuel consumption after launch, and a modal test is essential to investigate its effect. However, when relying on modal test to characterize the free vibration characteristics, the testing time is excessively increased and accuracy is reduced. Therefore, this paper suggests a modal test method with finite element analysis to overcome these drawbacks. A cylindrical structure filled with liquid are considered as a study model, and modal tests and finite element analyses are performed. The modal tests are conducted by an impulsive method using an impact hammer and accelerometers. Through the comparison of the modal test and the finite element analysis results, the validity of the proposed modal test method is verified. In addition, the free vibration characteristics and the tendency for the cylindrical structure according to the liquid filled ratio were investigated.

• Journal of Korean Society of Transportation
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• v.32 no.3
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• pp.227-238
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• 2014

There is no question that railroad investment is crucial for better transport systems and the Korean government has continued to invest in railroad facilities. Nevertheless, the modal share of railroad, in particular, for freight has decreased. This is because rail freight transport can hardly meet customer needs such as just-in-time(JIT), a door-to-door service, compared to road transport, to be specific, trucking which can directly carry the freights to the final destinations. This has made the value of the railroad infrastructure less, which has been operated for the past 114 years. This study proposes a new freight movement concept called Piggy Back System. This system can carry freight trucks on the trains and deliver the freights to the final destinations. It can make a door-to-door deliver system possible for railroad transportation, which is the key factor for modal shift from road to railroad. For implementing this, this study proposes three important things: the cost-efficient reforming way of railroad yard that has been used for the past 114 years, the diagram plan of train services, and some technical reviews like clearance limits. This is the first study with practical proposals and solutions on this topic in Korea. The suggestions of this study cut down distribution costs by more than seven trillion won.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.17-24
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• 2016

At present, summer cloudburst and local torrential rainfalls have increased in this country, because of climatic change. Therefore, studies on prevention of soil loss have been actively proceeded, and Korea Forest Service has offered landslide hazard map. Landslide hazard map divides risks into 5 classes, by giving weight with 9 kinds of elements. In August 25 2014, soil loss occurred in the whole Oryun Tunnel, Geumjeong-gu, Busan, because of local torrential heavy rain. As a result of comparing with landslide hazard map, the area where soil loss occurred in reality is a safety zone on hazard map. Rainfall, soil map, geological map, forest type map, gradient, drainage network, watershed, basin shape, and efflux of the whole Oryun Tunnel where soil loss occurred were analyzed. As a result of an analysis, it is judged that soil, forest type, much efflux and peak discharge, degree of water network and basin shape of a place where landslide occurred are causes of soil loss. It is judged that efflux, peak discharge, and basin shape by the localized rainfall that is not considered in landslide hazard map of them are the biggest causes of soil loss. It is judged that efflux, peak discharge, degree of water network and basin shape by the rainfall are important through a study on a causual analysis on soil loss in the whole Oryun Tunnel where is one of occurrence area where a lot of propertywere lost by the record local torrential rainfalls. A localized torrential downpour should be prepared by considering these elements on judgement of a landslide hazard area.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.634-639
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• 2005

Purpose : An understanding of the immunological process is required if primary prevention of atopic diseases is to be developed in early childhood. But, it is too hard to distinguish atopy from nonatopy under the age of two clinically, because the expression of phenotype and cytokines is vague in early childhood. We evaluated DNA methylation changes at Th2 interleukin-4 gene in peripheral blood from atopic children. Methods : We selected 15 allergic children(mild : eight, moderate to severe : seven) and seven normal controls by using family allergy scores and clinical histories. We measured Total IgE and Der f II specific IgE levels and cultured peripheral blood mononuclear cells with Der f II stimulation and extracted DNA from Der f II specific T cells. We examined the change of CpG methylation in DNA from atopic and nonatopic children. Results : In T cells from normal children, IL-4 DNA were predominantly methylated; otherwise, CpG demethylation occurred in Der f II specific T cells from allergic children. Conclusion : IL-4 DNA methylation changes occurred in T genes from allergic children and DNA methylation assay in early childhood.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.663-672
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• 2009

In this studies, the adsorption test using Chlorella pyrenoidosa was conducted to examine the effect of Pb adsorption according to various immobilized methods such as Ca-alginate, K-carrageenan, and Polyacrylamide. From the results, the duration to need to reach adsorption equilibrium was delayed according to the immobilization. And, the higher adsorption capacity of immobilized Chlorella pyrenoidosa was represented in the higher concentration of Pb, the smaller amount of immobilizing agent, and the higher pH of solution. The maximum adsorption capacity of Pb was shown in the adsorption test using Chlorella pyrenoidosa immobilized with Ca-alginate even though it was sensitive pH. The adsorption results properly represented with Freundlich isotherm equations. And, pseudo second-order chemisorption kinetic rate equation was applicable to all the biosorption data over the entire time range. The FT-IR analysis showed that the mechanism involved in biosorption of Pb by Chlorella pyrenoidosa was mainly attributed to Pb binding of carbo-acid and amide group. Adsorbed Pb on immobilized Chlorella prenoidosa was easily desorbed in the higher concentration of desorbents(NTA, HCl, EDTA, $H_2SO_4,\;Na_2CO_3$). Among the several desorbents, NTA showed the maximum desoption capacities of Pb from Chlorella pyrenoidosa immobilized with Ca-alginate and K-carrageenan and EDTA was the most effective in Chlorella pyrenoidosa immobilized with polyacrylamide. The desoprtion efficiency in the optimum condition was 90.0, 83.0, and 80.0%, respectively.

• Journal of Pharmaceutical Investigation
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• v.23 no.3
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• pp.165-177
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• 1993

The relationship between the plasma haloperidol (HP) concentration and clinical response, and the effects of its active metabolite, reduced haloperidol (RH) on clinical response of HP were investigated in schizophrenic patients. In clinical study I, with 17 schizophrenic patients (male 8, fermale 9) who were administered with three different fixed doses of HP (15, 30 and 50 mg/day) for 3 weeks, the concentrations of HP and RH in plasma and blood and clinical response had been checked before and every week during the study. The clinical response was evaluated by the method of brief psychiatric rating scale (BPRS), and relative improvement of clinical response based on baseline BPRS (before drug treatment) was calculated. The concentrations of HP and RH in plasma and blood were assayed by HPLC. In clinical study II, the plasma RH/HP concentration ratios were checked in 11 patients who were administered with high doses of HP, over 60 mg a day, because of the poor clinical response at usual doses of HP. Plasma HP concentration and relative improvement of BPRS at 3 week in schizophrenic patients showed a 'curvilinear' relationship, and the clinical response was improved relatively over 50% based on the baseline BPRS in the range of $5{\sim}57\;ng/ml $ of HP in plasma. Also, the plasma RH concentrations were increased nonlinearly as the plasma HP concentration increased, and in high plasma HP concentration, over 30 ng/mI, clinical response gradually decreased, while the plasma RH/HP concentration ratio increased nonlinearly. Blood partition coefficients of HP and RH were not changed according to daily HP dose and duration of drug therapy. From these results, it is noted that the higher plasma RH/HP concentration ratio, resulted from the accumulation of RH as HP concentration increased, might explain the 'curvilinear' decrease of HP clinical response.