• KIEAE Journal
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• v.8 no.1
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• pp.11-18
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• 2008

The purpose of this study is to analyze application methods and structural characteristics of each element of environment-friendly European housing through classification of skin types. The results of the study are following. 1) The skins are classified by three types; single skin with multi layers, double skin with single layer and double skin with multi layers. 2) Most single skins with multi-layer are composed with wooden louvers, sun blinds and insulating windows. There are introduction of atrium and balcony, and variation sectional space composition according to cases. 3) There are two types of double skins; to put cavity between inner skin and outer skin and more extensional spaces such as balconies, corridors and stair halls. Solar walls and mechanical ventilators are often introduced to double skins with multi-layer. 4) The functions of the latest environment-friendly skins are vary from controllers and buffers of indoor environmental elements such as temperature, light, air and sound to equipments to perform essential functions to efficiently operate HVAC systems.

• Earthquakes and Structures
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• v.25 no.5
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• pp.307-323
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• 2023

This study compares two prominent design provisions, National Design Specification (NDS) and Eurocode 5, on load-carrying capacity calculations and failure analysis for mortise-tenon joints. Design procedures of double-shear connection from both provisions were used to calculate load-carrying capacity of mortise-tenon joints with eight different bolt sizes. From this calculation, the result was validated using finite element analysis and failure criteria models. Although both provisions share similar failure modes, their distinct calculation methods significantly influence the design load-carrying capacity values. Notably, Eurocode 5 predicts a 6% higher design load-carrying capacity for mortise-tenon joints with varying bolt diameters under horizontal loads and 14% higher under vertical loads compared to NDS. However, the results from failure criteria models indicate that NDS closely aligns with the actual load-carrying capacity. This indicates that Eurocode 5 presents a less conservative design and potentially requires fewer fasteners in the final timber connection design. This evaluation initiates the potential for the development of a wider range of timber connections, including mortise-tenon joints with wooden pegs.

• Coupled systems mechanics
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• v.9 no.2
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• pp.147-161
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• 2020

Constructive merging of "basic" systems of different behavior creates hybrid systems. In doing so, the structural elements are grouped according to the behavior in carrying the load into a geometric order that provides sufficient load and structure functionality and optimization of the material consumption. Applicable in all materializations and logical geometric forms is a transparent system suitable for the optimization of load-bearing structures. Research by individual authors gave insight into suitable system constellations from the aspect of load capacity and the approximatemethod of estimating the participation of partialstiffnesswithin the rigidity ofthe hybrid system. The obtained terms will continue to be the basisfor our own research of the influence of variable parameters on the behavior of hybrid systemsformed of glued laminated girder and cable of different geometric shapes. Previous research has shown that by applying the strut-type hybrid systems can increase the load capacity and reduce the deformability ofthe free girder.The implemented parametric analysis pointsto the basic parameterin the behavior of these systems-the rigidity ofindividual elements and the overallstiffnessofthe system.The basic idea ofpre-stressing is that, in the load system or individual load-bearing element, prior to application of the exploitation load, artificially challenge the forcesthatshould optimize the finalsystembehaviorin the overall load. Pre-stressing is possible only if the supporting system orsystem's element possesssufficientstrength orstiffness, orreaction to the imposed forces of pre-stressing. In this paper will be presented own research of the relationship of partial stiffness of strut-type hybrid systemsofdifferentgeometric forms.Conducted parametric analysisofhybridsystemswithandwithoutpre-stressing, and on the example of the glulam-steel strut-type hybrid system under realistic conditions of change in the moisture content ofthe wooden girder,resulted in accurate expressions and diagramssuitable for application in practice.

• Journal of the Korean Wood Science and Technology
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• v.49 no.1
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• pp.57-66
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• 2021

In recent years, the use of cross laminated timber (CLT) has been evolving. In addition, CLT manufactured with various species such as Japanese cedar has been developed to utilize the local resources in each country. However most factories in Japan produce CLT by bonding the laminae in width direction for orthogonal layers, where grain of element is perpendicular to the grain of outer layer, and this process is considered to be one of the factors that reduce productivity. A new wood based material (hereinafter referred to as Ply-lam) using wooden panel such as plywood for the orthogonal layer was developed in order to improve productivity in CLT manufacturing and improve quality. Japanese cypress lamina was used for the parallel layer, where grain of element is parallel to the grain of outer layer, of CLT and Korean larch plywood was used for the orthogonal layer, in order to effectively use Korean larch and expand the utilization of Japanese cypress. The cross-sectional construction of the Ply-lam was 5-layers 5-plies, and the dimensions were 1000 mm (width) × 150 mm (depth) × 4000 mm (length). As a performance evaluation of the manufactured Ply-lam, strength tests such as out-of-plane bending, in-plane bending, out-of-plane shearing and in-plane shearing tests were carried out. As the result of this study, Ply-lam composed of Japanese cypress lamina panels and Korean larch plywood showed very higher out-of-plane bending strength compared to the standard strength of CLT. And the result obtained in other tests seems to show a sufficiently high value.

• The Korea Journal of Herbology
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• v.24 no.3
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• pp.121-128
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• 2009

Objectives : The present study purposed to examine the effect of Cudraniae Lignum, which is the wooden part of Cudrania tricuspidata Bureau (Moraceae), on cytokine secretion from the joint cells of mice with arthritis induced by collagen and verify its efficacy against rheumatoid arthritis. Methods : We prepared the hot-water extract, ethanol extract and methanol extract of Cudraniae Lignum, and tested their effects on cytokine secretion from the joint cells of mice with arthritis induced by collagen. Results : 1. Cudraniae Lignum reduced the secretion of inflammatory cytokines such as IL-1$\beta$, INF-$\alpha$ and IL-6 from joint cells. 2. The effect for reducing the secretion of IL-1$\beta$, TNF-$\alpha$ and IL-6 was strong in order of methanol extract, ethanol extract and hot water extract. 3. Considering the effect on cytokine secretion, the effective element is soluble in organic solvent, and is not volatile. 4. The ethanol extract and methanol extract of Cudraniae Lignum lowered the survival rate of cells significantly, but still the survival rate was over 92%, suggesting the low toxicity of the extracts. Conclusions : Cudraniae Lignum is considered effective for rheumatoid arthritis, and the effective element is considered soluble in organic solvent.

• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.44-52
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• 2011

Louisiana Museum of Modern Art near Copenhagen is the most visited art museum in Denmark. It was originally founded by the director of the time, Knud W. Jensen and designed by two Danish architects, Vilhelm Wohlert and J${\o}$rgen Bo. The first part of the museum was built and opened to the public in 1958. The first part consisted of just a few exhibition spaces and glass corridors. But museum has been expanded step by step into a large park-like museum throughout 40 years of time. Louisiana museum has a unique environment in which art, architecture and nature are inter-related together. There was a very clear background for this museum atmosphere that was created by Knud W. Jensen from the very beginning. He wanted to make 'a sculptural park' or 'a low pavilion in the park'. The concept of 'park' was the key element. The architects, especially Vilhelm Wohlert who studied at the western area of the United States and influenced by the bay area architecture as well as the oriental wooden structure, interacted with the director's idea fully and made an invisible architecture in which 'Experience of Space' is the most important aspect. This thesis aims to analyze several crucial spaces of the museum and to find a hidden design characteristics. Chapter 2&3 explains general backgrounds and main design philosophy. Chapter 4 studies each parts' spatial experience and design methods with 3-dimensional diagrams. Chapter 5 tries to make an overall design characteristics that underlines the whole museum environment. The significance of Louisiana museum is not only in the fact that it is the most visited, but also in the fact that the role of architecture is to make a better environment where human and art are harmonized together within nature. The utopian idea of the founder started in doubt almost 50 years ago has been already successful in this small but vibrant park.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.2
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• pp.93-102
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• 2011

Existing research for store has been localized in that of Seoul area, and research for the Japanese style store built under the rule of Japanese Imperialism has not been done properly owing to national sentiment. This research established Naju that inland pillage is available along Yeongsan River after opening of Mokpo harbor. I will compare modernization developmental process of building of Korean style store with that of Japanese Style store, so obviously try to make clear the activities of modernization by linking social and economical change with Joseon merchants' life. I will try to light up the position of korean style store in Naju area in history of architecture by analyzing two styles of stores into urban architectural element, putting process of change in order and translating it according to flow of age. The development process of Korean restaurant stores and that of Japanese counterparts are rather relative. Whereas Japanese accumulated wealth through oppression and exploitation of the people of Joseon the former dynasty of present day Korea, the people of Joseon could not but be oppressed and depressed. On the other hand, while the dynamic liberation movements of Joseon merchants managed to develop based on the vitality that was growing ever more, Japanese chose to back down to some degree by exercising appeasing policy. The efforts to take initiative by shattering off the submissive attitude can be found from the ability fostering movement, Gwangju students campaign and new construction or remodeling of hanok the traditional Korean house as commercial building in the 1920s. The changing phase of the people breaking away from subjugated relation to subjective attitude can be found in the commercial districts.

• Journal of Ocean Engineering and Technology
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• v.27 no.4
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• pp.1-8
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• 2013

Many PE (pre-erection) blocks are supported by wooden, concrete, or steel supports when they are stocked in the outdoor areas of a shipyard. Their positions and numbers are planned on the basis of the workers' experience. Recently, many shipyards have been making PE blocks with various shapes and weight distributions because of the variety of ships and building technologies. Therefore, it is now necessary to deal with blocks that they have no experience with. We propose a method to conveniently and quickly evaluate the structural safety of PE block supports, without the need for special knowledge and technology related to structural analysis. This method can reduce the large number of man hours (MH) normally needed for the analysis. The three-dimensional grillage analysis is performed for a simplified grillage model of a PE block. For efficiency, the grillage model of the PE block is automatically built from its three-dimensional CAD model, and its weight is also automatically distributed on the grillage model. The integrated system has been comprehensively implemented to perform the grillage analysis for the reaction forces on block supports. This paper describes how to make a grillage model of a PE block and estimate the weight distribution of the block on this grillage model. These steps are verified by comparing the supports reaction forces to those of the 3D finite element analysis for the PE blocks that are provided by a shipyard.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.23-29
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• 2005

The fancy veneer flooring board is high value-added wooden material. The classification of the flooring boards by the observation with the naked eye causes color difference among fancy veneers. It turned out that this inaccuracy of color difference among fancy veneers increased in case of the identification by metamerism or the flooring construction. Therefore, this study was performed to classify fancy veneers produced from 3 species such as Tilia sp., Betula sp., and Acer sp. which were identified with the naked eye by Light and Dark grade, by using CIELAB. In addition, each specie's threshold on CIERGB was investigated and a range of hue, saturation and intensity by an application of HSI color model were studied. Intensity of the HIS color model could be the best value to be used when color, saturation and intensity of the HSI color model were used for the classification of the flooring board's color. In addition, it seemed that color range of all three criteria lied between $45^{\circ}$ and $55^{\circ}$. In the case of identification by threshold of RGB element, considering only specific color element value is unlikely to lead to accurate classification of fancy veneers of flooring board.

• Composites Research
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• v.34 no.3
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• pp.155-160
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• 2021

Metamaterials are complexes of elements that can create properties not found in naturally occurring materials, such as changing the direction of forces, creating negative stiffness, or altering vibration and impact properties. In the case of wood pile metamaterials that are easy to manufacture and have excellent performance in reducing vibration and shock in the vertical direction, basic research on variables affecting shock transmission is needed to reduce shock. Although research on impact reduction according to geometrical factors is being conducted recently, studies on the effect of material variables on impact reduction are insufficient. In this paper, finite element analysis was carried out by variablizing the geometrical properties (lamination angle, diameter, length) and material properties (modulus of elasticity, specific gravity, Poisson's ratio) of wood pile cylinders. Through finite element analysis, the shape of the wooden pile cylinder delivering impact was confirmed, and the effect of each variable on the reduction of impact force and energy was considered through main effect diagram analysis, and frequency band analysis was performed through fast Fourier transform. proceeded In order to reduce the impact force and vibration, it was found that the variables affecting the contact area of t he cylinder have a significant effect.