• Transactions of the Korean Society of Automotive Engineers
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• 제21권5호
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• pp.157-161
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• 2013

It is well known that the targeted fuel efficiency could only be achieved by more than 40% reduction of the vehicle weight through improved design and extensive utilization of lightweight materials. In order to obtain the goal of the weight reduction of automobiles, the researches about lighter and stronger spring link have been studied without sacrificing the safety of automotive components. In this study, the weight reduction design process of spring link could be proposed based on the variation of von-Mises stress contour by substituting an aluminum alloys (A356) having tensile strength of 245 MPa grade instead of SAPH440 steels. In addition, the effect of the stress and stiffness on shape variations of the spring link were examined and compared carefully. It could be reached that this approach could be well established and be contributed for light-weight design guide and the safe design conditions of the automotive spring link development.

• IEMEK Journal of Embedded Systems and Applications
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• 제9권3호
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• pp.145-150
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• 2014

This paper presents an effective vision based method for LED traffic light detection at the daytime. First, the proposed method calculates horizontal coordinates to set region of interest (ROI) on input sequence images. Second, the proposed uses color segmentation method to extract region of green and red traffic light. Next, to classify traffic light and another noise, shape filter and haar-like feature value are used. Finally, temporal delay filter with weight is applied to remove blinking effect of LED traffic light, and state and weight of traffic light detection are used to classify types of traffic light. For simulations, the proposed method is implemented through Intel Core CPU with 2.80 GHz and 4 GB RAM, and tested on the urban and rural road video. Average detection rate of traffic light is 94.50 % and average recognition rate of traffic type is 90.24 %. Average computing time of the proposed method is 11 ms.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.51-55
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• 2007

In this paper Statistical Energy Analysis has been considered to predict high frequency air borne interior noise. Dash panel Insulation is major part to reduce engine excitation noise. Transmission loss and absorption coefficient are considered to predict dash insulation performance. Transmission lose is derived from coupling loss factor and absorption coefficient is derived from internal damping loss factor. Material Biot properties were used to calculate each loss factors. Insulation geometry thickness distribution was hard to measure, so FeGate software was used to calculate thickness map from CAD drawing. Each predicted transmission losses between conventional insulation and light weight insulation were compared with SEA. Transmission loss measurement was performed to validate each prediction result, and it showed good correlation between prediction and measurement. Finally interior noise prediction was performed and result showed light weight insulation system can reduce 40% weight to keep similar performance with conventional insulation system, even though light weigh insulation system has lower sound transmission loss and higher absorption coefficient than conventional system.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제13권6호
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• pp.2757-2762
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• 2012

Sewage pipelines are one of important infra-structures. The main reasons of sewage pipelint failure are improper backfill materials and compaction controls in field. Especially, it is very difficult to compact the lower part of circula pipelines. In order to overcome these problems, the prefabricated light-weight plastic foundation was developed. Couple of load-displacement tests were carried out to get the characteristic of failure. From the limited laboratory loading tests, the use of prefabricated light-weight plastic foundation is an alternative to solve the difficulty of backfill materials and compaction control.

• KIEAE Journal
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• 제14권4호
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• pp.133-138
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• 2014

The present study was carried out to assess the basic material properties and thermal behavior of light-weight foamed concrete panel mixed with PCM (Phase Changing Material). To do so, this study fabricated light-weight foamed concrete (1.0kg/m3) in pre-foaming method and mixed it with PCM micro capsule of 1-dodecanol and melamine to examine its physical and thermal properties. The results confirmed strength reinforcement effect by proper replacement ratio of fly-ash, which is an industrial by-product, and PCM. In addition, it found out that PCM-mixed light-weight foamed concrete had time delay and temperature reduction effect within the range of PCM phase transition according to the rise of outdoor temperature. It was also observed that the insulation performance of PCM-mixed light-weight foamed concrete was more dependent upon thickness than PCM replacement ratio.

• Journal of Korean Society of Steel Construction
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• 제23권3호
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• pp.275-282
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• 2011

A recent development of seismic design, which is required among environmentally friendly members, increased the concern on light-weight concrete. Extending around the building, the structural design which is applied for light-weight concrete has been increased. This study therefore evaluates the bending resistance and the shear resistance involved using four specimens that were manufactured and tested. The parameters used in this study exist. This study investigates the structural performance of composite slab using light-weight concrete with KCI (2007).

• Journal of the Korean Crystal Growth and Crystal Technology
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• 제27권4호
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• pp.167-172
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• 2017

In this study, high performance patching repair mortars with light weight and sulfuric acid resistance properties were suggested. Their performance estimation were investigated based on KS F 4042 using patching repair mortar with light weight aggregate and soluble polymer of Type I and sulfuric acid resistance mortar of Type II, From these results, it was confirmed that these motors were satisficed and improved by all standard tests of KS F 4042.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.305-306
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• 2010

Recently, concrete have been used not only for structural purpose but also for various other purposes. The goal of this research is to develop porous and pervious light-weight concrete in order to apply to filters, which primarily treats rain water. Because Porous and pervious light-weight concrete is discontinuum with large amount of porosity, its physical characteristic is completely different from that of ordinary concrete. The basic properties such as the change in porosity rate depending on mixing proportion and the mechanical characteristics of porous and pervious light-weight concrete were experimentally evaluated.

• Computers and Concrete
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• 제19권5호
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• pp.555-566
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• 2017

Recently some efforts have been performed to combine the advantages of light-weight and self-compacting concrete in one package called Light-Weight Self-Compacting Concrete (LWSCC). Accurate prediction of hardened properties from fresh state characteristics is vital in design of concrete structures. Considering the lack of references in mixture design of LWSCC, investigating the proper mixture components and their effects on mechanical properties of LWSCC can lead to a reliable basis for its application in construction industry. This study utilizes wide range of existing data of LWSCC mixtures to study the individual and combined effects of the components on the compressive strength. From sensitivity of compressive strength to the proportions and interaction of the components, two equations are proposed to estimate the LWSCC compressive strength. Predicted values of the equations are in good agreement with the experimental data. Application of lightweight aggregate to reduce the density of LWSCC may bring some mixing problems like segregation. Reaching a higher strength by lowered density is a challenging problem that is investigated as well. The results show that, the compressive strength can be improved by increasing the of mixture density of LWSCC, especially in the range of density under $2000Kg/m^3$.

• Journal of the Korea institute for structural maintenance and inspection
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• 제11권2호
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• pp.109-116
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• 2007

The purpose of this paper is to evaluate the fire resistant performances of load-bearing wall using both composite and steel stud panel infilled with light-weight formed mortar under axial loading according to KS F 2257(1999). The minimum requirement of 2 hours fire resistant rating is needed for the residential and commercial buildings under the fire regulation of Korea. From test results, it is found that two types of specimen composed of the hybrid stud and steel stud panel filled with light-weight formed mortar fited in with the requirement of 2 hours fire resisting rate for the load-bearing wall. In the conclusions, the specimen with hybrid stud shows predominating fire-resistant performance on the adiabatic effects rather than that of the steel stud specimen.