• Journal of the Korean Wood Science and Technology
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• v.41 no.2
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• pp.100-104
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• 2013

Bearing occurs by the rotations of members induced from horizontal or vertical load at traditional wooden joint in frame. The bearing between wooden members is not occurring at the whole surface of joint, but occurring only at the particular bearing area. In this study, partial bearing according to the different grain direction was evaluated. The partial compressive strength showed 3 times higher than pure compressive strength perpendicular to grain, 1.5 times higher than parallel to grain and 3.3 times higher than both of them. It is expected that this result can be very importantly applied when evaluating and analyzing the actual behavior of traditional wooden mortise and tenon joint.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.3-7
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• 2002

The die casting process was used to manufacture a alternator housing for automobile. Specially automobile parts were required light and hight strength. Therefore simulation have been carried out die casting process of the alternator housing. In this paper, we investigated about characteristics of the die casted alternator housing the HPDC(High Pressure Die Casting) process. Also we designed the die casting die with the simulation results of the alternator housing. The MAGMAsoft and Auto-CAD was used as computer simulation and design code and used material was ADC12(Aluminum Die Casting Alloy). We present the results of filling behavior and design of die process of the alternator housing cast. The result obtained about filling behavior and design of die of the cast showed good agreement with test result.

• International Journal of Concrete Structures and Materials
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• v.8 no.1
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• pp.69-81
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• 2014

In this study, portland cement (PC) has been partially replaced with a Class F fly ash (FA) at level of 70 % to produce high-volume FA (HVFA) concrete (F70). F70 was modified by replacing FA at levels of 10 and 20 % with silica fume (SF) and ground granulated blast-furnace slag (GGBS) and their equally combinations. All HVFA concrete types were compared to PC concrete. After curing for 7, 28, 90 and 180 days the specimens were tested in compression and abrasion. The various decomposition phases formed were identified using X-ray diffraction. The morphology of the formed hydrates was studied using scanning electron microscopy. The results indicated higher abrasion resistance of HVFA concrete blended with either SF or equally combinations of SF and GGBS, whilst lower abrasion resistance was noted in HVFA blended with GGBS.

• Structural Engineering and Mechanics
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• v.31 no.1
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• pp.1-10
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• 2009

An experimental investigation was conducted to evaluate the performance of mortars with and without Metakaolin (MK) exposed to elevated temperatures $200^{\circ}C$, $400^{\circ}C$, $600^{\circ}C$ and $800^{\circ}C$ for two hours. The binder to sand ratio was kept constant (1:5.23). The ordinary Portland cement (OPC) was replaced with MK at 0%, 5%, 10% 20% and 30%. All mixtures were designed to have a flow of $94{\pm}5%$. The compressive strength of mortars before and after exposure to elevated temperature was determined. The formation of various decomposition phases were identified using X-ray diffractometry (XRD) and differential thermal analysis (DTA). The microstructure of the mortars was examined using scanning electron microscope (SEM). Test results indicated that MK improves the compressive strength before and after exposure to elevated temperature and that the 20% cement replacement of MK is the optimum percentage.

• Land and Housing Review
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• v.2 no.1
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• pp.53-60
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• 2011

In this study, development tests varying with concrete strength, development length, and the rate of fiber mix ratio are carried out to evaluate the development characteristics of high-strength concrete member with 80MPa, and the applicability of estimated standards of development length in KCI 2007. As a result, it can be expected that minimum development length of KCI 2007 is applicable to high-strength concrete member with 80MPa. Although the mixed fiber(NY+PP) to secure fire resistance performance of high-strength concrete is included up to 0.1%, it does not affect the development characteristics.

• Journal of Powder Materials
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• v.31 no.4
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• pp.329-335
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• 2024

As the demand for electric vehicles increases, the stability of batteries has become one of the most significant issues. The battery housing, which protects the battery from external stimuli such as vibration, shock, and heat, is the crucial element in resolving safety problems. Conventional metal battery housings are being converted into polymer composites due to their lightweight and improved corrosion resistance to moisture. The transition to polymer composites requires high mechanical strength, electrical insulation, and thermal stability. In this paper, we proposes a high-strength nanocomposite made by infiltrating epoxy into a 3D aligned h-BN structure. The developed 3D aligned h-BN/epoxy composite not only exhibits a high compressive strength (108 MPa) but also demonstrates excellent electrical insulation and thermal stability, with a stable electrical resistivity at 200 ℃ and a low thermal expansion coefficient (11.46×ppm/℃), respectively.

• Journal of Wind Energy
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• v.13 no.4
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• pp.80-89
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• 2022

In this paper, a study was conducted to evaluate the safety of pitch reducers for 8 MW class wind turbines. The housing and carrier of the pitch reducer were subjected to structural analysis for the ultimate load by load duration distribution (LDD). As a result of the finite element analysis of the housing parts, the part with the highest stress was the output housing, and the equivalent stress was 522.4 MPa and the safety factor was 1.14. As a result of finite analysis of the carrier, the highest stress occurred at 80.5 MPa in the first carrier, and the safety factor was 10.3. In addition, extreme strength and life analysis by LDD load were performed for gears and bearings included in each stage. The strength analysis of the planetary gear train was conducted based on ISO 6336, and the stability evaluation of the bearings through life analysis based on ISO 281 found all to be safe.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.769-773
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• 2002

The die easting process was used to manufacture a motor housing for automobile. Specially automobile parts were required light and high strength. Therefore simulations have been carried out die casting process of motor housing. In this paper, we investigated about characteristics of the die casted motor housing with HPDC(High Pressure Die Casting) process. Also the MAGMAsoft was used as computer simulation code and used material was ADC12(Aluminum Die Casting Alloy). We present the results of filling behavior and solidification process of a motor housing cast. The analysis results obtained about filling behavior and solidification of cast showed good agreement with test results.

• Journal of Families and Better Life
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• v.20 no.1
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• pp.103-114
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• 2002

Housing is a central place fur elderly and it can be influenced to the quality of life for them. Most low income elderly has much problems on their housing. It needs to be developed for more various ones which considered in the way of their economic and physical conditions. This case study was aimed to supply (or a basic data for developing a housing for tow income elderly through the analysis of elderly housing of Melbourne in Australia. This study evaluated two types of government housing and five types of community housing available to elderly People on low income allowing them to live independently. Results of the research were as follows. 1) High rise apartment living was differentiated from other housing types. Such accommodation had drawbacks, for example it made the elderly difficult to get along with neighbours. 2) Community housing had more various types of housing than government housing and was aimed at encouraging community interaction between residents. Some community housing residents joined the management of the housing committee. As a result, it made the elderly very confident and promoted a good relationship between them and young generations. 3) The strength of community housing was that the elderly could choose the place to live within the community which was familiar to them. 4) The managers in broth government housing and community housing had many roles as adviser and mediator for residents as well as managing the complex. 5) A policy of housing for low income elderly is changing now from management by government appointees to one governed by the community 6) Most elderly prefer to live close to facilities such as medical and shopping centers and convenient transportation and wished to remain in their familiar community as long as possible.

• Environmental Engineering Research
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• v.11 no.4
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• pp.201-207
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• 2006

A simple empirical model with good quantitative prediction of inter-particle and intra-particle distance in a cake layer with respect to ionic strength was developed. The model is an inverse length scale with functions of interaction energy and hydrodynamic factor and it explains that the inter-particle and intra-particle distance in a cake is directly related to the effective size of particles. Particle compressibility with respect to ionic strength was also predicted by the model. The model corroborated very well with experimental results of polystyrene microsphere latex particles microfiltation in a dead end operation. From the results of the model, specific cake resistance could be controlled by the same variables affecting the height of particle energy barrier described by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory.