• 한국지반공학회논문집
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• 제30권11호
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• pp.51-60
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• 2014

한계상태설계법의 하나인 하중저항계수설계법의 이용이 북미를 중심으로 점차 확산되고 있는 가운데, 국내에서도 이에 대한 연구가 활발하게 진행되고 있다. 하지만, 국내에서는 자료가 충분히 확보되지 못하여 기초구조물의 설계에 AASHTO에서 제안한 저항계수를 설계에 이용하고 있다. AASHTO에서 제안하고 있는 저항계수는 북미에 보편적으로 존재하는 암반조건을 이용하여 결정된 저항계수로서, 국내지반에 적합한 저항계수를 독자적으로 개발할 필요가 있다. 또한, 기존의 신뢰성 분석 기법에서는 하중저항계수를 결정할 때, 저항의 최소값을 0으로 가정하는 일반적인 대수정규 분포를 이용하기 때문에, 이로부터 산정한 파괴확률은 비현실적이라고 알려져 있다. 따라서, 이를 개선하기 위하여 저항계수를 산정할 때 저항의 하한값이 0이 아닌, 현실적으로 의미가 있는 하한지지력을 이용하는 방법이 최근에 고안되었다. 따라서, 본 연구에서는 국내에서 수행된 현장타설말뚝 13본에 대한 재하시험자료를 면밀히 분석하여 저항계수를 산정한 다음, 현실성 있는 하한지지력을 산정하여 저항계수 값을 보정하였다. 그 결과, 목표신뢰도지수가 3.0일때, 기존의 신뢰성 분석 기법으로부터 산정된 주면저항계수와 선단저항계수는 각각 0.13-0.32, 0.19-0.29 이었으며, 하한지지력을 보정하여 구한 주면저항계수와 선단저항계수는 Carter & Kulhawy 공식의 경우 각각 8%와 13% 증가하였다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 추계 학술발표회 논문집
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• pp.223-230
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• 2002

Earthquake resistance design has been developed many countries like Japan, USA, Mexico, New Zealand etc., which countries have experienced many earthquakes. Nowadays, earthquake resistance design has come into worldwide use. In Korea, the seismic design regulations have been established since 1988 in order to minimize the economic losses. Recently performance based design method has been adopted as a new Earthquake resistance design method. These regulations, however, are targeted for newly constructed buildings, In Korea, there are no regulations for existing buildings that built before 1988. On the other hand, in Japan and USA, the seismic performance evaluation is coded. In Japan, the evaluation index which can measure seismic performance has been made. So, we need to prepare the regulations that evaluate the seismic performance, furthermore proper retrofitting design guideline needs to be proposed when remodeling old buildings. In this research, various seismic performance evaluation methods which are being used in Japan and USA are reviewed in order to establish seismic performance evaluation index for those existing old structures in Korea.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.341-344
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• 2008

By investigating a series of catastrophic tunnel fires, this research aims to evaluate the fire resistance design method as applied to tunnel structures in Korea. It is shown that the current strategy is oriented towards smoke control and ventilation to reduce the loss of life. As structural collapse is not regarded, a general guide is proposed to obtain the fire safety.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.50-52
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• 2019

Dynamic resistance equalization is a viable technique to balance SOC of cells in a parallel-connected battery configuration due to high equalization performance, simplicity and low-cost. However, an inappropriate design of the equalization resistor can degrade the equalization performance and increase the power loss. This paper proposes an optimization process to design the equalization resistors to minimize power loss and equalization error. The simulation results show that the optimally designed resistor significantly enhance the performance in comparison with the conventional fixed-resistor equalization.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.659-662
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• 2004

An analysis of the AF is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted AF, from the ship collision risk assessment is compared to an acceptance criterion. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions. To determine the design impact lateral resistance of bridge components such pylon and pier, the numerical analysis is performed iteratively with the analysis variable of impact resistance ratio of pylon to pier. The design impact lateral resistance can vary greatly among the components of the same bridge, depending upon the waterway geometry, available water depth, bridge geometry, and vessel traffic characteristics.

• 대한조선학회논문집
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• 제55권3호
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• pp.196-204
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• 2018

Present paper shows the basic design procedure for platform support vessel operating in open sea, and hull form development process. General design concept considering the operating mission, operating sea condition and shipping freight, etc. is explained shortly. For the hull form design, the initial hull form was designed based on the reference PSVs. The resistance and propulsion test results for the initial hull form with twin Azimuth thruster were analyzed and a few items for improvement were derived. At the next stage, main parameters including Length, Cp-curve, Cb, Lcb, etc. were changed totally for the hull form improvement. Furthermore, 3 different bulbous bows for the fore-body design to reduce the wave resistance and after-body design to reduce the residual resistance were carried out. The best hull form among the 3 fore-bodies with same after-body was selected through the comparison of wave resistance calculation results. Twin ducted Azimuth thruster with the smaller propeller diameter than the former were adapted to increase the propulsive efficiency. The final hull form with the twin Azimuth thruster was evaluated to satisfy more than the target design speed 14 knots in sea condition with sea margin 15% at the 5,000kW BHP through the model test in KRISO.

• 산업공학
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• 제10권2호
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• pp.109-114
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• 1997

The tread pattern of tire is represented by a great number of design factors, such as groove breadth of circumference direction, breadth direction, rib breadth, block length, kerfs, tread breadth and tread radius, etc. It is not efficient in time and cost to analyze the rolling resistance for a great number of real tread pattern, because It requires lots of pattern forming handwork. In order to optimize tread pattern for rolling resistance, the experiment is planed and analyzed by Taguchi's robust design methods. We identified the important design factors for Rolling Resistance, determined the optimal condition and calculated prediction value which is related. Using the experiment data and the analyzed data, we developed the program which could predict Rolling Resistance. It is expected that time and cost may be reduced in designing and developing new tire tread pattern.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.847-847
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• 2004

Automobile cooling fans are operated with a radiator module. To design low noise, high performance cooling fan, radiator resistance should be considered in the design process. The system (radiator) resistance reduces axial velocity and increases effective angle of attack. This increasing effective angle of attack mechanism causes blade stall, performance decrease and noise increase. In this paper, To analyze fan performance, freewake and 3D CFD calculations are used To design high performance fan with consideration of system resistance, optimal twist concept is applied through momentum and blade element theory. To predict fan noise, empirical formula and acoustic analogy methods are used.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.21-25
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• 2008

It is the aim of this study to investigate the fire resistance design Guidelines for high-strength concrete structure for example compressive strength more than 40Mpa. It is well know that explosive spalling due to fire attack of high strength concrete is related to concrete failure. so, the purpose of this study introduce the fire A Studty on the Fire Resistance Design Guidelines for High-Strength Concrete Structures of AIK for the response of explosive spalling of high strength concrete.

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권5호
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• pp.577-587
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• 2017

The recent IMO MEPC regulation on EEDI, EEOI and increased fuel cost has worsened the financial condition of the small and medium sized passenger ferry companies, and it is situated to acquire the economic ships with a pretty high resistance performance. The purpose of this research is to develop a design method on the efficient gooseneck bulb for the middle-sized passenger ferry operated in the Far East Asian seas. The hull forms are designed by varying the gooseneck bulb parameters to find the changes on the resistance performance according to the shape of bulb. The numerical series tests are made to derive the regression equation for estimating the resistance through analyzing the data statistically. This equation is set as an objective function, and then using the optimization algorithm searches for the optimal combination of the design variables. After a hull form is designed corresponding to optimized parameters.