• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.228-233
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• 2008

The reflection type photoelastic experiment can be used more effectively than the transparent type photoelastic experiment in industrial fields. However, the reflection type photoelastic experiment for orthotropic material has not been studied. Therefore, the reflection type photoelastic experimental hybrid method for the fracture mechanics of orthotropic material was developed in this research. Comparing the results obtained from this method with those from the hybrid method for isotropic material about the same isotropic specimen, the validity of this method was verified. And then, the reflection type photoelastic experiment for orthotropic material was applied to the orthotropic plates with a central crack of the various inclined angle. Using this hybrid method for the orthotropic material, it is able to obtain stress intensity factors and separate stress components at the vicinity of the crack-tip in orthotropic plates from only the isochromatic fringe patterns of isotropic coating material.

• 한국전기전자재료학회논문지
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• 제20권5호
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• pp.410-414
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• 2007

To prevent degradation of battery efficiency generated by serious current variation in rechargeable batteries, we researched a hybrid battery combining a super capacitor and a rechargeable battery. The hybrid battery shows high efficiency in a lifetime and a voltage drop. The hybrid battery was composed of a rechargeable battery, a current regulator and a super capacitor that can be used with supporting power. Before the experiment, the hybrid battery was simulated for current regulation and an electric current in a super capacitor by using the Pspice program. After that, we compared the efficiency of the hybrid battery with the efficiency of the normal battery. In this result, we demonstrated that the hybrid battery has a higher efficiency and a longer lifespan than the normal battery.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.35-38
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• 2002

In this paper, for digital x-ray conversion receptor development studied by hybrid technology of based on CdZnTe. For this study, First searched fabricate method of CdZnTe x-ray receptor. Second, search the phosphor material & fabricate method for scintillator layer. Fabricated sample is analyzed with physical & electric measurement. This result is showed good SNR ratio hybrid thechnology with direct method & indirect method. In this paper offer the method can reduce the dark-current in the hybrid X-ray detector.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.25-25
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• 2010

In this paper, we have investigated the electrical characteristics for solar-cell and wind power generator hybrid system. The output of electricity for solar cell - wind generator hybrid system were investigated according to the weather conditions at Naju province.

• Steel and Composite Structures
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• 제23권6호
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• pp.737-746
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• 2017

In this paper the influence of aspect ratio, height ratio and material angle on static and free vibration behaviour of orthotropic elliptic paraboloid shells is studied by using a four-node hybrid stress finite element. The formulation of the element is based on Hellinger-Reissner variational principle. The element is developed by combining a hybrid plane stress element and a hybrid plate element. A parametric study is carried out for static and free vibration response of orthotropic elliptic paraboloid shells with respect to displacements, internal forces, fundamental frequencies and mode shapes by varying the aspect and height ratios, and material angle.

• 한국건설순환자원학회논문집
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• 제9권3호
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• pp.311-321
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• 2021

콘크리트의 낮은 인장강도와 취성적인 특성 등의 약한 재료 특성을 개선하기 위하여 수년간 하이브리드 섬유보강 콘크리트에 관한 많은 연구가 진행되어 왔다. 그러나 비정질 강섬유와 유기섬유를 이용한 하이브리드 섬유보강 콘크리트의 특성에 관한 연구는 미진한 실정이다. 본 논문의 목적은 비정질 강섬유와 폴리아미드 섬유를 이용한 고성능 하이브리드 섬유보강 콘크리트의 압축 및 인장 거동을 평가한 후 이들에 대한 재료모델을 제안하는 것이다. 이를 위하여 목표 압축강도 40MPa 및 60MPa 각각에 대해서 비정질 강섬유와 폴리아미드 섬유를 총 부피비 1.0%로 설정하여 섬유 조합별로 고성능 하이브리드 섬유보강 콘크리트를 제작한 후, 압축 거동 및 인장 거동을 평가하였다. 고성능 하이브리드 섬유보강 콘크리트의 실험결과를 바탕으로 압축 및 인장거동에 대한 재료모델을 제안하였으며, 제안한 모델은 실험결과와 비교적 잘 일치하는 것으로 나타났다.

• 한국자동차공학회논문집
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• 제21권2호
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• pp.45-54
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• 2013

In this paper, a theoretical weight-reduction method was suggested to substitute an underframe material of a box-type bodyshell having cut-outs with an alternative light-weight material. To utilize the material substitution method previously developed for a box-type hybrid bodyshell not having cut-outs, we derived a box-type baseline model without cut-outs which is similar to the stiffness condition of a box-type bodyshell having cut-outs. To do this, the thicknesses of roof and walls of the baseline model were determined such that the deflection of the baseline model under a distributed vertical load condition is equal to the sum of the theoretical section deflections of the original box model with cut-outs. Next, to derive a hybrid bodyshell by under-frame material substitution, the material substitution method for a box-type hybrid bodyshell without cut-outs was applied to the box-type baseline model. Finally, we compared the FE simulation results of the derived hybrid bodyshells having cut-outs for various materials with the theoretical results of the suggested method, and we obtained their good correlations.

• 한국전기전자재료학회논문지
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• 제28권7호
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• pp.473-479
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• 2015

Hybrid supercapacitors with high power density and long cycle life are widely used for emergency power source of LED emergency luminaires. In this paper, we designed and fabricated a hybrid capacitor cell and a module for the LED emergency luminaires. Using hybrid supercapacitor cells (1,000 F, 2.8 V), we designed a module in a 10-year warranty considering aging and ESR. Considering the ESR and efficiency has been designed to module with 1,000 F 5.6 V design results in 2 series and 2 parallel combination. Module was used to confirm that the operation 77.5 minutes at room temperature, discharge LED emergency luminaires with 2 W. As a LED emergency luminaires of emergency power supply that we can support more than 10 years of life was confirmed the applicability of hybrid supercapacitor.

• 한국소음진동공학회논문집
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• 제19권3호
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• pp.274-281
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• 2009

The carbon fiber epoxy composite material and aluminum have many advantages over other materials because of their high specific stiffness and good fatigue characteristics. Basically, the propeller shaft of automobile requires bending frequency of higher than 2,700 Nm and high natural frequency of higher than 9,200 rpm occurred by fast revolution. For this reason, natural frequency and torsion torque characteristics of hybrid shaft was studied in variation of its outer-diameter and thickness. Vibration and torque characteristics of hybrid shaft were compared by torsion tester, natural frequency experiments and FE analysis. Designed hybrid shaft satisfied its vibration and torque characteristics when its outer-diameter was 60 mm and thickness was 5 mm. Therefore, hybrid material enables to manufacture one piece structure hybrid propeller shaft rather than current two piece structure.

• Corrosion Science and Technology
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• 제14권2호
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• pp.64-75
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• 2015

Single $TiO_2$ coating prepared by sol-gel process usually experiences cracks in coating layer. In order to prevent cracks, an inorganic-organic hybrid $TiO_2-SiO_2$ coating was synthesized by combining precursors with an organic functional group. Five different coatings with various ratios of (1:8, 1:4, 1:1, 1:0.25 and 1:0.125) titanium alkoxide (TBOT, Tetrabutylorthotitanate) to organo-alkoxysilane (MAPTS, ${\gamma}$-Methacryloxy propyltrimethoxysilane) on carbon steel substrate were made by sol-gel dip coating. The prepared coatings were analyzed to study the coating properties (surface crack, thickness, composition) by scanning electron microscope (SEM), focused ion beam (FIB), and Fourier transform infrared spectroscopy (FT-IR). Potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) were also performed to evaluate the corrosion characteristics of the coatings. Crack free $TiO_2-SiO_2$ hybrid coatings were prepared with the optimization of the ratio of TBOT to MAPTS. The corrosion rates were significantly decreased in the coatings for the optimized precursor ratio without cracks.