• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.96-102
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• 2008

For centuries now, wind tunnels have been a key element in scientific research in a number of fields. Experimenting with racecars, airplanes, weather patterns, birds, and various other areas has been made much easier because of its development. In the racing field, for example, the information gathered from this testing can mean the difference between winning and losing a race. Weather simulations can also provide valuable information regarding building stability and safety. This has become very important when designing buildings today. Valuable information concerning bird flight has also been collected based on wind tunnel testing. Wind tunnels have a variety of important uses in the world today. Wind tunnel that used here is an open loop low speed wind tunnel. The fundamental principles of this tunnel is moving the air using exhaust fan In the rear side, and placing the cube in the external balance system which used to measure the working force. This experiment is using 50mm cube of finished wood. From this experiment we can get Drag Force (FD), The Reynolds Number (Re) and The Coefficient of Brae (CD).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.3
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• pp.271-280
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• 2003

The purpose of the study presented in this paper is to develope the general model for capture of the linear and nonlinear response of a flexible diaphragm building in which there are significant contributions from the out-of-plane walls. Two single-story single-diaphragm half scale reinforced masonry buildings were tested by researchers at the United States Army Construction Engineering Research Laboratory (CERL). The first had a metal deck diaphragm. The second specimen had a diaphragm with a single layer of diagonal lumber sheathing, A multiple degree of freedom (MDOF) approach is adopted in this paper. The required stiffnesses and strengths of the components within this model are determined.

• Advances in materials Research
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• v.6 no.2
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• pp.221-231
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• 2017

The concept design of the typha strawbale masonry came up as a result of the urgent demand for a means of constructing sustainable buildings, both in rural and urban settlement, not only suitable for dwellers but for keeping farm products by structures that will respond to the environmental eco-system, coupled with the fact that such structures are also affordable, durable and easy to maintain during their service period. The effects of contact between plaster and the stacked strawbale of a masonry needs to be established and design optimization for durability and stability of the masonry be obtained. The assessment will involve the application of plaster materials (cement and natural earth) to the wall specimen panels. Past works have shown that plastered strawbale walls have adequate resistance against the appropriate vertical loads, and further showed that the earth plaster can bear higher stress than the cement plastered straw bale. There is the implication that the collapse or response of the earth-strawbale wall is significantly higher compared to that of cement-strawbale from other straw-based masonries. Therefore the allowable stresses of plastered typha strawbale shall be predicted for their optimum values using SAP2000. The stress stability of each masonry is obtained by analytical model using the best fit variables for the wall height and thickness.

• KIEAE Journal
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• v.13 no.2
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• pp.3-12
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• 2013

Recently, New Han-ok is in prevail because it has many good qualities as a dwelling. But the New Han-ok dwellers' needs and satisfaction ratio on their houses are not investigated yet. So, surveys on satisfaction ratio for New Han-ok were carried out to know New Han-ok's existing conditions and inhabitant's responses on New Han-ok dwellings. Followings are results. 1) Dwellers response that it is cool in summer and it is cold in winter. So, design and construction method against cold is needed for New Han-ok. 2) Window is the most picking element of New Han-ok for house improvement. 3) Window opening is main control method for cooling in summer. Warming sources in winter are various such as electricity, gas, oil, wood, etc. 4) PVC window structure and glasses were used for New Han-ok's window system as well as wooden window structure and Han-gi. 5) Interviewees are generally satisfied with New Han-ok's exterior view and inner spaces. Almost no humidifier is used. These results could be used for improvement of Han-ok and basic material for New Han-ok design.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.3
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• pp.247-254
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• 2010

Due to lightweight and high durability of glass-fiber reinforced polyester (GFRP) materials, they are promising alternatives to conventional construction materials such as steel, concrete and wood. As good application examples of GFRP materials, several types of temporary arch bridges were suggested and verified by finite element analyses in our previous study where snap-fit GFRP decks were applied. In this paper, we conduct a structural performance test to verify safety and serviceability of the temporary arch bridge, where snap-fit GFRP decks are assembled by bolts. The structural problems occurred in this test are also discussed and improvement of temporary arch bridges is suggested to resolve the occurred structural problems.

• Korean Journal of Acupuncture
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• v.19 no.1
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• pp.91-105
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• 2002

In the oriental medicine, the biological mechanism and pathogenic change have been based on the meridian. A Liver channel of those belong to the wood in the five element system, the Leg channel of the twelve primary channels, Absolute Yin(厥陰) in the three Yin channels and connect with Liver organ. Through the study on a liver channel, the results were as follows. Leg Absolute Yin is indicated for disease affecting the lower abdomen, uro-genital system, knee and thigh. Symptons associated with mind regulation system : hypochondria, a feeling of restlessness and the deficiency of Liver Yin. Symptons associated with disease of Absolute Yin.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.3
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• pp.217-223
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• 2008

Glass-fiber reinforced polyester (GFRP) composite material is a promising alternative to existing construction materials such as steel, concrete and wood due to light weight and high durability of GFRP composite material. If a temporary arch bridge is built by GFRP composite deck, rapid construction of the bridge and reuse of the GFRP composite deck are possible. In this paper, we develop a type of temporary arch bridges that can be built by easy assembling of GFRP composite decks. For this purpose, several possible types of temporary arch bridges are suggested and verified by finite element analysis.

• Structural Engineering and Mechanics
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• v.55 no.6
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• pp.1121-1137
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• 2015

High powered computers and engineering computer systems allow designers to routinely simulate complex physical phenomena. The presented work deals with the analysis of two finite element method optimization techniques (First Order Method-FOM and Subproblem Approximation Method-SAM) implemented in the individual Design Optimization module in the Ansys software to analyze the behavior of real problems. A design optimization is a difficult mathematical process, intended to find the minimum or maximum of an objective function, which is mostly based on iterative procedure. Using optimization techniques in engineering designs requires detailed knowledge of the analyzed problem but also an ability to select the appropriate optimization method. The methods embedded in advanced computer software are based on different optimization techniques and their efficiency is significantly influenced by the specific character of a problem. The efficiency, robustness and accuracy of the methods are studied through strictly convex two-dimensional optimization problem, which is represented by volume minimization of two bars' plane frame structure subjected to maximal vertical displacement limit. Advantages and disadvantages of the methods are described and some practical tips provided which could be beneficial in any efficient engineering design by using an optimization method.

• Resources Recycling
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• v.31 no.1
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• pp.3-11
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• 2022

Silicon is the most abundant metal element in the Earth's crust. Metallurgical-grade silicon (MG-Si) is an important metal that has wide industrial applications, such as a deoxidizer in the steelmaking industry, alloying elements in the aluminum industry, the preparation of organosilanes, and the production of electronic-grade silicon, which is used in the electronics industry as well as solar cells. MG-Si is produced industrially by the reduction smelting of silicon dioxide with carbon in the form of coal, coke, or wood chips in electric arc furnaces. MG-Si is purified by chemical treatments, such as the Siemens process. Most single-crystal silicon is produced using the Czochralski method. These smelting and refining methods will be helpful for the development of new recycling processes using secondary silicon resources.

• Steel and Composite Structures
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• v.50 no.6
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• pp.689-703
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• 2024

Construction of high-rise structures, formwork systems that can be installed quickly, resistant to external loads, can be used more than once, have become a necessity. Timber and composite timber materials are preferred in the formation of such formwork systems due to their durability, ease of assembly, light weight and easy to use more than one time. Formwork beams are the most commonly used structural component in the formation of such formwork systems, and these beams can be damaged for different reasons during their lifetime. In this study, H20 top P type timber formwork beams with 1800 and 2450 mm length which is among the products of DOKA(c) company is damaged under the effect of static loading up to a high load level of 85% of the maximum ultimate capacity and after being retrofitted using anchored CFRP strips, performance and behavior of the beams under the influence of various loading types such as static, fatigue and impact are investigated experimentally. Two different lengths of retrofitted timber formwork beams were tested by applying monotonic static, fatigue and impact loading and comments were made about the effects of the retrofit method on performance under different loading types.