• 정보관리학회지
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• 제33권2호
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• pp.103-133
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• 2016

최근 특허기술의 가치평가가 크게 강조되고 있으며, 특허의 피인용횟수는 특허기술 가치평가에 있어 중요한 척도이다. 본 연구에서는 국내 특허를 대상으로 피인용횟수에 영향을 주는 변수들을 도출하기 위하여 일반화 선형모형 회귀분석을 실시하였다. 총 12개의 변수를 형태적, 기술적 그리고 개념적 요인으로 분류하였고, 국내 의료기기 특허 14개의 분야에 적용하여 분석한 결과 출원인 국적, 출원인 유형, 발명자 수, 출원국가 수, IPC 수, 참고문헌 수, 서지결합도가 특허 피인용횟수에 유의미한 영향을 미치는 것으로 나타났다. 본 연구는 국내 실정에 적용 가능한 연구를 수행함으로써 국내 특허에 대한 인용분석 방법론에 있어서 실질적인 기초적 자료를 제공했다는데 의의가 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.713-716
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• 2008

본 연구는 잔골재 부분 대체 Bottom-Ash 활용에 관한 기초 물성치 연구로서 Bottom-Ash의 잔골재 대체 콘크리트의 압축강도 테스트와 이들 실험을 통한 내구성능(노후화) 영향지수를 분석하였다. 잔골재 대체 Bottom-Ash 콘크리트 압축강도 실험의 경우 잔골재로 대체 시 발생하는 콘크리트의 초기경화시간의 단축 및 Ash 내 유해물질 방지를 위하여 고화제(GRG-21)를 활용, 40, 50, 60%의 W/C 비율별로 콘크리트를 배합 압축강도 실험을 실시하였다. 각각의 실험체에 대한 강도-내구공극 상관관계 조사를 위하여 압축강도 실험 후 활용되어진 공시체는 내부공극 측정을 위한 적절한 사이즈로 샘플링, 분석되었다. 분석요소로는 각종 내부 공극의 크기, 모양 직경별 함유량의 분포상태 등이 고려되었으며 이들 조사를 통하여 압축강도-내부공극 간 상호관계를 예측하였다. 부가적으로 콘크리트 재료변화는 콘크리트 내구성 자체의 변화를 가져 올 것으로 판단하여 상용프로그램(ATENA)을 활용, 콘크리트 압축실험에 따른 구조물의 균열패턴을 예측,조사하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.131-136
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• 2006

일면전단시험은 전단면의 응력을 직접 측정하므로 평면변형시 강도를 파악할 수 있는 등의 많은 장점을 가지고 있으며, 시험조작이 간편하기 때문에 실용적으로도 우수한 것으로 판단된다. 그러나 사질토의 경우에 의한, Dilatancy에 의한 체적변화과정에서 공시체와 전단상자의 주면마찰력이 전단면의 수직 응력을 증감시키기 때문에 구해지는 강도가 과대 또는 과소하게 나타나는 것으로 알려져 있다. 그러나 반력판측에 장착한 하중계를 통해 전단면의 수직응력을 직접 측정 제어하는 형식으로 개선되어 주면마찰력의 영향을 해소하였다. 따라서 본 연구는 반력판측에 하중계를 장착한 개량형 다단식 단순전단시험기를 개발하여 사질토의 정압(CD)조건 전단시험을 수행하여 강도특성과 전단강도에 미치는 영향을 개량형 일면전단시험의 결과와 비교하였다. 그 결과 정압조건의 일면전단시험과 단순전단시험에 의한 강도정수는 조밀한 모래의 경우는 거의 비슷하게 나타나며, 느슨한 모래의 경우는 일면전단이 다소 크게 나타났다. 그리고 단순전단과 일면전단시험에서의 Dilatancy거동에는 큰 차이가 나타나지 않았다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 F
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• pp.2610-2612
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• 1999

In controlling vector of induction motor, PID controller is required much time as the expert should control manually a gain of controller according to plant or a change of circumstances. Accordingly, this paper has gotten a gain of PID controller used neural network by self-funning method in order to settle above problem. The neural network can describe an input/output features in spite of non-linear system which is hard to get mathematical model by controlling the strength of connection by learning. It has a strong character against a distortion and noise of input information, and is suitable modeling of diver-variable system which is composed of several input/output. This paper has represented the self-tunning method for gain of PID controller used neural network when using PID controller to control speed of induction motor, and has checked strong characters against distortion and noise of input information through simulation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.260-260
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• 2010

In recent years, polymer/clay nanocomposites have generated a great interest, both in industry and in academia, because they often exhibit remarkable improvement in material properties when compared with the virgin polymer or conventional micro and macro-composites. Among these properties are stiffness, strength, dimensional stability and permeability. [1-3] The dispersion of hydrophilic silicates in a hydrophobic matrix like Polyethylene (PE) is difficult because of the difference in character between PE and Montmorillonite (MMT). Therefore, it is necessary to modify PE with polar groups, which can increase the hydrophilicity of PE. In this study, High density polyethylene (HDPE)/$Mg(OH)_2$/Montmorillonite (MMT) nanocomposites having a various compositions were prepared by a melt blending technique with an internal mixer and properties namely mechanical, morpology, rheological and thermal properties were investigated

• Steel and Composite Structures
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• 제34권4호
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• pp.547-559
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• 2020

Buckling restrained braces (BRBs) were developed as an enhanced alternative to conventional braces by restraining their global buckling, thus allowing development of a stable quasi-symmetric hysteretic response. A wider adoption of buckling restrained braced frames is precluded due to proprietary character of most BRBs and the code requirement for experimental qualification. To overcome these problems, BRBs with capacities corresponding to typical steel multi-storey buildings in Romania were developed and experimentally tested in view of prequalification. The first part of this paper presents the results of the experimental program which included sub-assemblage tests on ten full-scale BRBs and uniaxial tests on components materials (steel and concrete). Two different solutions of the core were investigated: milled from a plate and fabricated from a square steel profile. The strength of the buckling restraining mechanism was also investigated. The influence of gravity loading on the unsymmetrical deformations in the two plastic segments of the core was assessed, and the response of the bolted connections was evaluated. The cyclic response of BRBs was evaluated with respect to a set of performance parameters, and recommendations for design were given.

• Steel and Composite Structures
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• 제34권4호
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• pp.561-580
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• 2020

Buckling restrained braces (BRBs) were developed as an enhanced alternative to conventional braces by restraining their global buckling, thus allowing development of a stable quasi-symmetric hysteretic response. A wider adoption of buckling restrained braced frames is precluded due to proprietary character of most BRBs and the code requirement for experimental qualification. To overcome these problems, BRBs with capacities corresponding to typical steel multi-storey buildings in Romania were developed and experimentally tested in view of prequalification. In the second part of this paper, a complex nonlinear numerical model for the tested BRBs was developed in the finite element environment Abaqus. The calibration of the numerical model was performed at both component (material models: steel, concrete, unbonding material) and member levels (loading, geometrical imperfections). Geometrically and materially nonlinear analyses including imperfections were performed on buckling restrained braces models under cyclic loading. The calibrated models were further used to perform a parametric study aiming at assessing the influence of the strength of the buckling restraining mechanism, concrete class of the infill material, mechanical properties of steel used for the core, self-weight loading, and frame effect on the cyclic response of buckling restrained braces.

• 대한화학회지
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• 제33권5호
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• pp.538-544
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• 1989

1-(phenoxymethyl)benzotriazole(1)과 1-(thiophenoxymethyl)benzotriazole(2) 유도체중의 X 치환기가 전자를 끄는 세기(${\rho}<0$)와 methylene group의 인접 Y원자에 의한 local diamagnetic effect(Y=O(1)>S(2)), 그리고 용매의 극성파라미터($E_T$=Kcal/mol:acetone;42.2>chloroform;39.0)가 클수록 methylene group의 수소원자($H_m$)와 용매사이에 B-형의 수소결합성이 증가되었으며 (1)의 methylene group 에 대한 substituent chemical shift($CH_2-SCS$)에 미치는 자유 에너지 직선관계(LFER)의 조성은 아세톤 용액 중에서 장(F)(또는 유발(I))-효과 보다 공명(R)-효과가 더 크게 나타나는 용매 의존적인 경향이었다.

• Geomechanics and Engineering
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• 제10권2호
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• pp.247-256
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• 2016

In this paper, based on understanding the design theories on soil stabilization, a series of soil stabilizers were prepared with different kinds of industrial wastes such as calcined coal gangue (CCG), blast furnace slag (SS), steel slag (SL), carbide slag (CS), waste alkali liquor (JY), and phosphogypsum (PG). The results indicated that when the Portland cement (PC) proportion was lower than 20% in the stabilizer, for the soil sample selected from Wuhan (WT) and Beijing (BT), the unconfined compress strength (UCS) of the stabilized soil specimens could increase 4.8 times and 5.4 times respectively than that of the specimens stabilized only by PC; compared with the UCS of the specimen stabilized only by PC, the UCS of the specimen which was made from soil sample WT and stabilized by the stabilizer composed only by CCG, CS, and PG increased 1.5 times, and UCS of the specimen which was made from soil sample BT and stabilized by the stabilizer composed only by SS, JY, and PG increased 4.5 times.

• 국제초고층학회논문집
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• 제6권1호
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• pp.49-72
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• 2017

The Guangzhou International Finance Centre (IFC) is a landmark building that symbolizes the emerging international strength of Guangzhou, China's third largest city. It is also one of the dual iconic towers along the main axis of Guangzhou Zhujiang New Town. Arup adopted a total engineering approach in embracing sustainability and aiming at high efficiency solutions based on performance-based design principles covering structures, building services, fire engineering, vertical transportation, and façade performance to constitute an efficient and cost-effective overall building design. Through dynamic integration of architectural and engineering principles, Guangzhou IFC represents a pioneering supertall building in China. It adopts a diagrid exoskeleton structural form that is clearly expressed through the building's façade and gives the building its distinctive character. The aerodynamic shape of the building not only presents the aesthetic quality of elegant simplicity, but also reduces the effects of wind, thereby reducing the size and weight of the structure. State-of-the-art advanced engineering methods, such as optimization techniques and nonlinear finite element modelling, were applied in parallel with large-scale experimental programs to achieve an efficient and high-performance design taking into account the constructability and cost-effectiveness for a project of this scale.