• Steel and Composite Structures
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• v.17 no.3
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• pp.215-236
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• 2014

The flexural behaviour of steel beams significantly affects the structural performance of the steel frame structures. In particular, the flexural overstrength (namely the ratio between the maximum bending moment and the plastic bending strength) that steel beams may experience is the key parameter affecting the seismic design of non-dissipative members in moment resisting frames. The aim of this study is to present a new formulation of flexural overstrength factor for steel beams by means of artificial neural network (NN). To achieve this purpose, a total of 141 experimental data samples from available literature have been collected in order to cover different cross-sectional typologies, namely I-H sections, rectangular and square hollow sections (RHS-SHS). Thus, two different data sets for I-H and RHS-SHS steel beams were formed. Nine critical prediction parameters were selected for the former while eight parameters were considered for the latter. These input variables used for the development of the prediction models are representative of the geometric properties of the sections, the mechanical properties of the material and the shear length of the steel beams. The prediction performance of the proposed NN model was also compared with the results obtained using an existing formulation derived from the gene expression modeling. The analysis of the results indicated that the proposed formulation provided a more reliable and accurate prediction capability of beam overstrength.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.7
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• pp.71-79
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• 2002

A new rapid prototyping process, Variable Lamination Manufacturing using a 4-axis-controlled hotwire cutter and expandable polystyrene foam sheet as a laminating material of the part (VLM-S), has been developed to reduce building time and to improve the surface finish of parts. The objective of this study is to reconstruct the surface of the original 3D CAD model in order to generate mid-slice data using the advancing front technique. The generation of 3D layers by a 4 axis-controlled hot-wire cutter requires a completely different procedure to generate toolpath data unlike the conventional RP CAD systems. The cutting path data for VLM-S are created by VLM-Slicer, which is a special CAD/CAM software with automatic generation of 3D toolpath. For the conventional sheet type system like LOM, the STL file would be sliced into 2D data only. However, because of using the thick layers and a sloping edge with the firstorder approximation between the top and bottom layers, VLM-Slicer requires surface reconstruction, mid-slice, and the toolpath data generation as well as 2D slicing. Surface reconstruction demands the connection between the two neighboring cross-sectional contours using the triangular facets. VLM-S employs thick layers with finite thickness, so that surface reconstruction is necessary to obtain a sloping angle of a side surface and the point data at a half of the sheet thickness. In the process of the toolpath data generation the surface reconstruction algorithm is expected to minimize the error between the ruled surface and the original parts..

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.3
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• pp.19-28
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• 2010

The construction projects are recently having changes in their magnitude and complexity. Therefore, the amount of information created and managed by participants over project phases is enormous and this may cause difficulties in consistent and integrated data management. Because of the change in construction projects, there is a need to apply more logical and systematic ways to deal integrated data management. For the solution to this, BIM(Building Information Modeling), a new paradigm for integrated management of the information over project life-cycle, has been seriously considered. Also, the Korean Public Procurement Service announced that project over 50 billion Korean Won should introduce BIM into procurement starting from 2012. However, the studies and development have lack on studies of applying BIM and managing the data made using BIM in pre-design and maintenance stage. In pre-design stage, the concept of schematic design model is made to support for making major decisions concerning the size, shape and cost of the project. To decide the cost for the building in this stage by making use of BIM, estimating the amount of building materials used for constructing should be preceded. In this study, the pre-design BIM is explained to gain a better understanding of its process, since this paper focused on space programming stage. Finally, the paper suggests the concept process of estimating the amount of materials in building interior finishing from selecting the type for the elements of each space made to support the client for making decisions in space programming stage based on pre-design BIM.

• Structural Engineering and Mechanics
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• v.47 no.6
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• pp.881-898
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• 2013

This paper describes analytical investigation into a new dual function system including a couple of shear links which are connected in series using chevron bracing capable to correlate its performance with magnitude of earthquakes. In this proposed system, called Chevron Knee-Vertical Link Beam braced system (CK-VLB), the inherent hysteretic damping of vertical link beam placed above chevron bracing is exclusively utilized to dissipate the energy of moderate earthquakes through web plastic shear distortion while the rest of the structural elements are in elastic range. Under strong earthquakes, plastic deformation of VLB will be halted via restraining it by Stopper Device (SD) and further imposed displacement subsequently causes yielding of the knee elements located at the bottom of chevron bracing to significantly increase the energy dissipation capacity level. In this paper first by studying the knee yielding mode, a suitable shape and angle for diagonal-knee bracing is proposed. Then finite elements models are developed. Monotonic and cyclic analyses have been conducted to compare dissipation capacities on three individual models of passive systems (CK-VLB, knee braced system and SPS system) by General-purpose finite element program ABAQUS in which a bilinear kinematic hardening model is incorporated to trace the material nonlinearity. Also quasi-static cyclic loading based on the guidelines presented in ATC-24 has been imposed to different models of CK-VLB with changing of vertical link beam section in order to find prime effectiveness on structural frames. Results show that CK-VLB system exhibits stable behavior and is capable of dissipating a significant amount of energy in two separate levels of lateral forces due to different probable earthquakes.

• Journal of the Korean Society of Costume
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• v.57 no.4 s.113
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• pp.126-142
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• 2007

The second part of this study is to typify plural sexuality articulated with fashion images in men's and women's popular fashion magazines in Korea since 2000 and ultimately to infer sexual ideology codified in modern fashion by a framework of this study, the socio-semiotic model. From this, sexuality represented in modern fashion was typified as follows: in women's fashion Traditional Femininity, Glamor Femininity, Androgynous Femininity, Babydoll Femininity and Genderless sexuality, while in men's fashion Traditional Masculinity, Macho Masculinity, Androgynous Masculinity, Adolescent Masculinity and Genderless sexuality. The conclusion of this study is as follows: First, modern fashion has been changed from a means expressing gender and class into a sign vehicle representing the new ruling system of age and sexual desire. The binary oppositional sexuality on center of man in the 19 C capitalist period has been gradually pluralized towards the post-capitalist period. Next, mainstream society in Korea is still positioned in the traditional heterosexuality, keeping the vertical power relationship between man and woman even in the post-modern period. However, the fact that both Traditional Femininity and Androgynous Femininity acquire the position of dominant femininity connotes the change of modern femininity. Finally, plural sexuality represented in modern fashion has family resemblance and it shows contextual flexibility within contemporary period as well as a historical context. As a result, sexuality floats with a specific historical and socio-cultural context, and fashion as a material culture represents a masquerade as a identity vehicle, which constructs and de-constructs sexuality at the same time.

• KSBB Journal
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• v.11 no.5
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• pp.529-535
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• 1996

Methyl frucloside was purified from the aqueous sugar/methyl fructoside solution by liquid chromatography using Amberlite IRA-900, strong anion-exchange resin. The optimum operating conditions, resolution and productivity of methyl fructoside were discussed to evaluate the practical feasibility of the proposed chromatographic separation process of methyl fructoside which is useful as a new starting material for sugar ester synthesis. The linear chromatography model with HETP was well applied to the chromatographic separation process of methyl fructoside and the theoretical solution successfully predicted the elution chromatogram of methyl fructoside and sucrose at different superficial linear velocity of eluent for rectangular feed with different loading volume of packed bed. The optimum operating conditions were found to be 75% with the loading volume of packed bed at 1.13 cm/min of the superficial linear velocity at $60^{\circ}C$, and gave the productivity of methyl fructoside of 7 mg/g-resin/h with the resolution of 1.1.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1522-1530
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• 2014

High-rise residential complex type is getting important as new town development and urban regeneration in the downtown area. However, literature review of high-rise residential complex and research on satisfaction analysis of real residents are lack. Therefore, this paper is analyzing environmental friendly planning elements of high-rise building as housing subdivision, inside of building, facility, and maintenance by a survey on experts. The purpose of this paper is to suggest improvement method of environmental-friendly planning elements of high-rise residential complex by M-IPA. First, as a result, the part of housing subdivision has to keep complex land utilization, environmental-friendly transportation. Second, the part of inside of building shows that ecological housing subdivision, indoor air environment urgent and indoor temperature environment keeps maintaining. Finally, the part of facility/maintenance shows that material and facility, and index of energy management are urgently needed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.1-11
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• 2000

A low frequency, high power hydroacoustic transducer with 7 tonpilz piston elements assembled in a circular array suitable for marine application, such as the transmission of underwater information and the development of new fisheries resources in the deep sea zone was designed. A modified Mason's model was applied to monitor and to simulate the transducer behavior at each step during the fabrication. The in air, and in water constructed tonpilz transducer was tested experimentally and numerically by changing the size and the type of the material for head, tail and acoustic window. Also, the developed transducer was excited by pulse signals and the received waveform was analyzed. The resonance peaks in the transmitting voltage response(TVR) of a single tonpilz element without housing were observed at 11.33kHz in air and 10.93kHz in air and 10.93 kHz in water, respectively, with the overall electrical-acoustic efficiency of 43.7%. The value of TVR of single tonpilz element with aluminum housing in water was 129.87dB re 1 $\mu$Pa/V at 12.25 kHz with the frequency bandwith of 2.15 kHz and half beam angle of 30.2$^{\circ}$at -3dB.The resonance peaks in the transmitting voltage response of the 7 element circular transducer were observed at 11.50 kHz in air and 11.45 kHz in water, respectively. The value of TVR in water 144.84 dB re 1$\mu$Pa/V at 11.5kHz with the frequency bandwith of 4.25 kHz and the half beam angle of $22.3^{\circ} $ at -3dB.Reasonable agreement between the experimental measurements and the theoretical predictions for the directivity patterns, TVRs and the impedance characteristics of the designed transducer was achieved.

• Biomolecules & Therapeutics
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• v.21 no.3
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• pp.246-250
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• 2013

We previously reported that the extract from cuttlebone (CB) has wound healing effect in burned lesion of rat. In present study, the main component of CB extract was analyzed and its wound healing activity was evaluated by using in vitro acute inflammation model. The extract of CB stimulated macrophages to increase the production of TNF-${\alpha}$. The extract also enhanced the production of TGF-${\beta}$ and VEGF, which were involved in angiogenesis and fibroblast activation. The treatment with CB extract enhanced proliferation of murine fibroblast. CB extract also induced the activation of fibroblast to increase the secretion of matrix metalloproteases 1 (MMP1). The constituent of CB extract which has wound healing activity was identified as chitin by HPLC analysis. The mechanism that the CB extract helps to promote healing of burned lesion is associated with that chitin in CB extracts stimulated wound skins to induce acute inflammation and to promoted cell proliferation and MMP expression in fibroblast. Our results suggest that CB or chitin can be a new candidate material for the treatment of skin wound such as ulcer and burn.

• Korean Journal of Medicinal Crop Science
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• v.17 no.1
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• pp.1-7
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• 2009

Several parts of Lythrum salicaria were used for this study. Scavenging activities on radicals, inhibitory activity on linoleic acid peroxidation and total phenol contents of extracts from root, flower, and aerial part were evaluated. Flower and root selected from in vitro assay were subjected to in vivo assay on $CCL_4$-induced liver injury rat model for two weeks. Carbon tetrachloride intoxication on rats produced large amounts of hepatic lipid peroxidation product, thiobarbituric acid reactive substance (TBARS) compared with normal rats. Treatment with root extract of L. salicaria (LSR) showed effective inhibitory activity on lipid peroxidation product. Administration with LSR extract significantly alleviated $CCL_4$-induced increase in GPT activity which were more effective than silymarin. The results of this study suggest that root and flower of L. salicaria have antioxidant and liver protecting activities, and root part is the most effective candidate to develop a new functional material.