• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.116-119
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• 2004

The use of higher strength materials frequently requires the change of design provisions. Following to the previous researches, high strength reinforcing bars have a weak point about the development and splice length. Based on the previous research about high relative rib area, bond strength between reinforcing bars and concrete can be improved by the control of rib height and spacing. But, the code provisions do not include these specific shape of reinforcing bars. So, the purpose of this paper is to determine the effect of relative rib area to the bond strength. This paper describes the experiment and analysis of 5 beam-spliced specimens containing D25 with relative rib areas ranging from 0.073 to 0.17. The test results are also analyzed to make a design formula about the calculation of splice length on the consideration of relative rib area.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1084-1089
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• 2004

Recently, Orthotropic steel deck bridges, which have long span decks, have been regarded as one of economical as well as durable bridge types. However, Orthotropic steel deck bridge is used by a lot of welding, which may cause welding defect and deformation of connections. This kind of system happens some damages by the fatigue cracks of welding. The cross-connection of longitudinal rib and transversal rib is one of the weakest point because of the fatigue. The secondary stresses which are from the out-plane deformation of transversal rib and the torsion of longitudinal rib make the topical stress concentration phenomenon. But, it is principle that a Bulkhead Plate is not established in the domestic design standard. Therefore, it is estimated that a study for the installing of Bulkhead Plate is needed. This study with considering these circumstances proves efficiency of Bulkhead Plate and will be presented optimal design details through finite element analysis according to change the geometrical system of Bulkhead Plate and the cross-connection area of longitudinal and transversal rib

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.647-654
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• 2006

In orthotropic steel decks, it is likely to have defects due to fatigue damages because most of structural joints(the connection of longitudinal rib and transverse rib, the connection of deck plate and longitudinal rib) are connected by welds. However. orthotropic steel decks have many advantages. such as light weight and reduction of construction time. in comparison with concrete decks. Therefore. they are mostly used in long-span bridges and urban highway bridges. This study consists of the cause identication of fatigue damage and the suggestion of rational thickness on deck plate about the connection of deck plate and longitudinal rib. The results are as follows: fatigue damage cause at the connection of deck plate and longitudinal rib is local deformation in deck plate. And, rational thickness of deck plate is 16mm thickness.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.639-642
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• 2002

A new PDP barrier rib formation technique was investigated utilizing transparent soft maid made of silicon resin. Transparent soft mold was fabricated by pouring a silicone resin into the base mold made with photosensitive glass. The photosensitive barrier rib paste was coated on the glass substrate and dried in a 90 $^{\circ}C$ convection oven for 20min. The transparent soft mold was pressed on top of the semi-dry barrier rib layer and then irradiated with a UV lamp to a total dose of $900{\sim}1000mJ/cm^2$ The soft maid was then removed from the pressed barrier rib by winding up and fine pattern of barrier rib was obtained. The photosensitive barrier rib paste makes the demolding easy due to reduced interfacial forces and shrinking of paste materials.

• Journal of Chest Surgery
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• 제31권1호
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• pp.86-88
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• 1998

늑골에 발생하는 동맥류성 골낭종은 희귀한 질환으로 섬유성 이형성증이나 거대세포종과 감별을 요하는 질환이나 장골의 골간단이나 안면골에도 발생할 수 있다. 환자는 14세 남자 환자로 특이 증상없이 학교신체검사에서 발견된 환자로 핵자기공명촬영상 우측 제 4늑골에 동맥류성 골낭종이 발견되어 광범위 절제술후 현재 16개월까지 재발없이 경과 관찰 중이다.

• 한국유체기계학회 논문집
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• 제18권3호
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• pp.66-73
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• 2015

This paper deals with a parametric study on boot-shaped ribs in a rectangular cooling channel. Numerical analysis of the flow and heat transfer was performed using three-dimensional Reynolds averaged Navier-Stokes equations with the Speziale, Sarkar and Gatski turbulence model. The parametric study was performed for the parameters, tip width-to rib width, tip height-to-rib height, rib height-to-channel height, and rib height-to-width ratios. To assess the cooling performance and friction loss, Numsselt number and friction factor were defined as the performance parameter, respectively. The results showed that the cooling performance and friction loss were seriously affected by the four geometric parameters.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.839-844
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• 2007

In order to reduce resultant stress of the connection detail of longitudinal and rib and floor beam, in this study, the parameter studies for the reinforcement details as the bulk head and the vertical rib were preformed with FE analysis. As the result, it was shown that reinforcement detail with the bulk head plate in longitudinal rig reduced generally the principal stress at the connection detail, but the stress concentration of the weld toe parts occurring fatigue crack increased. However, it was known that the reinforcement detail with the vertical rib in the rib is more effective than the bulk head plate of the reduction stress concentration in the weld toe parts.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.451-454
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• 2005

The ㄱ type perfobond rib shear connector is a ㄱ type flat steel plate with a number of holes punched through. This connector can be effectively used in girder with high shear. The ㄱ type perfobond rib shear connector exhibit very stiff behaviour under service load conditions and also had the characteristic of retaining a significant amount of load after the attainment of ultimate capacity. A regression analysis, which is based on a model that takes into account the contributions of concrete dowels formed by the rib holes, the transverse reinforcement, the strength of concrete in front of the rib, and the ㄱ type plate as well as a nonlinear finite element analysis, is used in the derivation. An empirical equation for the design of ㄱ type perfobond rib shear connector is proposed.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.307-310
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• 2005

The effects of deformation properties on the bond of steel reinforcing bars to concrete are experimentally studies to expect the lap splice strength. Based on the previous research about relative rib area, lap splice strength between reinforcing bars and concrete can be improved by the control of rib height and spacing. This paper describes the testing and analysis of 15 beam-spliced specimens containing D25, D22, D19 with relative rib areas ranging from 0.066 to 0.162. The tests are analyzed to determine the effect of relative rib area(Rr) on the increase in bond strength. The tests also provide a preliminary indication of the effect of high relative rib area on the splice strength of uncoated bars.

• Journal of Advanced Marine Engineering and Technology
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• 제31권5호
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• pp.606-613
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• 2007

The 6m class high speed boat is developed with a durable hull and inflatable tube, which is called RIB(Rigid Inflatable Boat), for the purpose of marine leisure. In the stage of the conceptual design, its requirements to be optimized are determined based on the presented information of similar marine leisure RIBs. The 3-D graphical technique using Marine Rhino is utilized to optimize the compartment layout of RIB. The stability analysis is performed for the light and full load conditions with and without the inflatable tube. In addition, the sea keeping and hydrodynamic performance was tested using the proto-type ship in the sea condition. From the results of the computation and the sea trial test, it shows that the performance of the marine leisure RIB satisfies the speed, the convenience, and the stability requirements. This study provides the typical information of the design factors and the procedure to manufacture the marine leisure RIB.