Many of the structures constructed since the 1970s have begun to deteriorate. As a result, safety inspection / diagnosis and maintenance are expected to increase further, and long-term and systematic measures are urgently needed to prepare for the aging of major infrastructures. Currently, the safety inspection and maintenance of the structure is carried out by the method based on the utilization of the measurement data and the manager's experience, but the reliability and the accuracy are still insufficient. In other words, there is a limit to understanding the state change of bridges, such as abnormal behavior and gradual damages, therefore, it is necessary to have an accurate and reliable monitoring process using new techniques and systems. For this reason, I would like to examine the possibility of using cloud and big data in the field of infrastructure safety management.

This study aims to establish design and construction procedure in the fields of the repair and rehabilitation for existing concrete structures. The codes used in this study are ISO 16311 and ACI 562-16. The ISO 16311 and ACI 562-16 focused on maintenance and repair, respectively. After, we will make to design and construction guidelines to meet the domestic situation through analysis the repair and rehabilitation parts of the codes in detail.

In this study, a new strengthening alternative for RC structures, namely wing type steel frames, has been experimentally investigated under reversed cyclic loading. It has been observed that the usage of wing type steel frames considerably improve the capacity and sway stiffness of RC structures.

This study is to evaluate the seismic demand of reinforced concrete structure considering the incident angle of the ground motions. For this purpose, a three-story structure is numerically analyzed under the three ground motion records through a multi-component incremental dynamic analysis (MIDA). The MIDA, an implementation of Incremental dynamic analysis, investigates two components of seismic excitation in which all accelerations are scaled to spectral accelerations at the fundamental natural periods of the buildings. The obtained results indicate the influence of the incident angle should be considered in the assessment response of structures. Maximum inter-story drift of structure will behave in the elastic or inelastic range depending on the variable incident angle

It was studied structural design of nonuniform UHPC concrete structural members. UHPC concrete has the compressive strength of 120-200MPa, the tensile strength of 8-20MPa, and the tensile strain of 1.0-5.0%. There are two types of specimens of nonuniform members improved in bending and shear performances. The specimens were evaluated by beam load test induced by bending and shear failures.

Numerical behavior of GFRP(Fiber Reinforced Polymer) infill panel in steel frame structure was evaluated through the finite element analysis in this study. In order to numerical analysis, a experimental test results was used to develop a three dimensional finite element model of steel frame specimen. Based on the developed three dimensional finite element model of steel frame specimen, the behavior of GFRP infill panel in the steel frame specimen was evaluated. From the numerical analysis results, strength of the steel frame specimen with GFRP infill panel was governed by GFRP infill panel. Also, diagonal compression behavior governed the GFRP infill panel in the steel frame specimen in the numerical analysis results.

Transition piece of offshore wind turbine tower is one of the main parts which takes the direct load and pass on to the lower support structure. In this study, a new design method for the transition piece has been developed. The trasition piece was designed based on the the load flow which was analyzed by approximation and was evaluated by FEM.

Soundless Chemical Demolition Agent (SCDA) has been spotlighted for demolition of concrete structure or rock near or in urban areas and historical places since it does not produce dust or rock fragmentations compared to explosive and gas pressure blasting methods. However, there is no guideline or design code for the demolition of existing structures using SCDA. In this study, numerical analysis using ABAQUS is conducted in order to find a minimum required pressure for the initiation of crack in concrete body with SCDA and obtained results in this study could be a basic data for design of hole spacing for the demolition of the structures using SCDAs.

Recently, as the awareness of safety has become more important, studies on damage assessment techniques for building structures have been actively conducted. The damage of the building structure is caused by the decrease of the stiffness which is inherent dynamic characteristic of the structural system, and the decrease of stiffness acts as a direct variable connected to the collapse of the structure. there have been developed techniques for estimating the inherent dynamics of a structure to identify and evaluate damage to the structure. In this study, we estimate the layer mass due to the modeling error through the optimization algorithm, Genetic Algorithm, and use the optimization algorithm GA to optimize the error covariance matrix, system noise and measured noise covariance matrix We propose an optimal state estimation algorithm. The objective function of the GA algorithm is obtained by the residual which is the difference between the measured values obtained from the EKF calculation and the values obtained from the system model. We verified the feasibility of the algorithm through a 4-DOF system.

The purpose of this study is to evaluate the effect of steel fiber reinforced concrete on structural performance when applied to joints. For this purpose, the development length was designed not to satisfy the concrete structure criterion. Experimental results show that the maximum strength of steel fiber reinforced concrete increases by about 12% in the direction of the settling force. Also, due to the increase of the tensile strength of the concrete, the strength of the cracks increased by 33% in the positive direction.

In this paper, the flexural test of concrete member damaged due to Calcium leaching were performed to evaluate the characteristics of structural behavior. From the results, yield load, maximum load and flexural rigidity of RC member damaged by calcium leaching were decreased and the depth of the neutral axis was increased.

Recently, the use of duplex stainless steel which has a two-phase microstructure consisting of grains of ferritic and austenitic stainless steel has been increased in a variety of industrial fields. Especially, STS329FLD with lower nickel content and higher yield strength compared with austenitic stainless steel has been developed. In this paper, experiments have been conducted to investigate the structural behaviors of single shear duplex stainless steel(STS329FLD) bolted connection with four bolts. Specimens with relatively long end distance failed by block shear fracture accompanied with curling (out-of-plane deformation) and the curling reduced the ultimate strength.

It is necessary to develop the damage function to cope with the increasing damage of steel transmission towers. A simplify analysis to evaluate the performance resistance capacity, which is essential for the development of the damage function, was performed. The 154kv power transmission towers installed between Sokcho and Yangyang were selected as the target structures. Wind loads were calculated and applied to the target structures according to the domestic transmission and distribution facility design standards. As a result of this study, displacement according to wind speed of the target structure was derived.

The purpose of this research is to consider the qualitative and quantitative performance of reinforced concrete deteriorations using active infrared thermography (IRT) technique. An experiment of five different cases of environmental conditions was conducted on a concrete slab in laboratory. A comparison of the IRT results between normal and reinforced concrete is also discussed. The results showed that the absolute contrast between defective area and non-defective area increases with the increment of ambient temperature. Besides, the values of absolute contrast above delamination obtained from normal concrete showed high than those under effect of reinforcing steel bar.

Many existing RC Buildings were built before the seismic code was established, they need seismic retrofit performance. In this study, presents the evaluations of seismic performance and displacement ductility for two type RC Frames : existing RC frame without SRF(Super Reinforcement with Flexibility) and RC frames strengthened with SRF.

이익조정은 사적인 목적을 가지고 재무보고과정에 의도적으로 개입하거나, 이해관계자들에게 기업성과를 호도하는 일련의 과정 또는 선택을 의미한다. 해운기업의 경우 선박확보와 결부된 자본구조로 인해 부채계약을 위반할 가능성이 높고, 이에 따른 이익조정 동기 또 한 타 산업에 비해 높은 특징을 가지게 된다. 이에 본 논문은 2007년 이후 87개 해운기업을 대상으로 해운기업의 이익관리여부를 확인함과 동시에 수정 Jones모형을 통해 도출된 재량적발생액과 자본구조변수와의 관계 및 해운기업의 이익조정행태를 알아보고자 하였다. 해운기업의 이익관리 가능성을 확인하기 위해 분포도와 차이분석 및 FGLS분석을 실시하였으며, 분석결과 0에 근접하여 손실을 본 기업들의 이익조정 즉, 이익관리 가능성을 관찰할 수 있었다. 또한 자본구조관련 변수와 재량적발생액에는 부(-)의 관련성이 관찰되어 국내 많은 연구들과 유사 한 결과를 보여주었다. 현금흐름변수 또한 유의한 것으로 나타나, 국내기업의 현금흐름중시 경향이 자본구조와 재량적발생액사이에 부(-)의 관련성을 발생시킬 수 있다는 기존 연구를 뒷받침해 주었다. 해운기업의 이익관리행태에 대한 추가분석에서는 전기부채만기구조가 이익조정 과 부(-)의 관련성을 보였으며, 부채비율이 급격히 증가한 집단에서 이익조정의 가능성이 더 큼을 확인할 수 있었다.

수중음향통신은 다중경로로 인한 신호간의 간섭으로 성능이 열악하므로 채널 부호화의 적용은 필수적이다. 수중 통신에서 데이터 를 전송하기 위한 패킷의 구조는 동기 획득을 위해 데이터 전송 전에 PN 시퀀스를 데이터의 헤드 부분에 첨가하여 전송한다. PN 시퀀스는 송·수신 간에 서로 알고 있는 데이터를 이용하여 동기를 획득하는 기능을 하고 있으므로 PN 시퀀스는 채널 부호화를 하지 않고 전송된다. 이 러한 비부호화 된 PN 시퀀스는 대부분의 연구에서는 동기 획득을 위해 활용되지만 본 논문에서는 동기 획득 뿐 아니라 PN 시퀀스의 성능을 이용하여 데이터 필드의 성능 또한 예측할 수 있어 데이터 필드의 복호부에 정보를 제공할 수 있다. 본 논문에서는 다중 경로 전달 환경인 수중음향통신에서 원활한 통신과 함께 수신 신호의 성능을 향상시키기 위하여 낮은 SNR에서도 우수한 성능을 보이는 컨볼루션 부호화 기법 과 BCJR 복호 방식을 이용하여 다양한 부호화 율에서 비 부호화 된 PN 시퀀스의 오류율과 부호화 된 데이터 필드의 오류율의 상관관계를 시뮬레이션 및 실제 수중 실험을 통해 분석하여 효율적인 수신 구조를 제시하였다.

목적: 본 연구는 유소년 축구선수의 역경 극복 경험을 기반으로 한 축구 긍정심리자본 개념을 탐색할 목적으로 진행하였다. 방법: 긍정심리자본에 관한 선행연구 고찰하여 개방형 설문지를 제작해 서울과 경기 지역에 위치한 유소년 축구클럽 소속의 초ㆍ중등학교 축구선수 73명을 대상으로 자료를 수집하였다. 이후 검사지 개발 및 타당도 검증을 위해 262명의 유소년 축구선수가 참여하였으며, 확인적 요인분석을 위해 273명의 유소년 축구선수가 자료를 제공하였다. 수집된 개방형 설문지 자료는 귀납적 내용분석을 통해 범주화 하였으며, 범주화를 토대로 도출 된 결과는 SPSS 19.0과 AMOS 18.0을 이용하여 기술 통계 분석, 탐색적 요인분석과 확인적 요인분석으로 결과를 도출하였다. 결과: 첫째, 유소년 축구선수의 긍정심리자본은 총 114개의 원자료가 수집되었으며, 자기 신념, 한계 극복, 인내, 성장 발판 등 9개 하위 범주로 분류되었고, 이는 자기효능감, 회복탄력성, 낙관성, 희망 등 4개 범주로 분류되었다. 둘째, 탐색적 요인분석을 도출한 유소년 축구선수의 긍정심리자본 결과는 평균과 표준편차, 왜도와 첨도 등 비교적 타당한 결과를 나타냈다. 셋째, 확인적 요인분석을 통해 유소년 축구선수의 긍정심리자본은 14문항이 적합도 수준에 있어 만족하는 것으로 나타났다. 결론: 유소년 축구선수는 주관적 경험과 해석에 따른 역경을 경험하지만 자신의 심리자원을 토대로 극복하여 긍정심리자본을 형성하였다. 본 연구가 유소년 축구선수의 긍정심리자본개념을 이해함과 동시에 유소년 선수의 축구 긍정심리자본 구축에 관심의 계기가 되기를 기대한다.

본 연구에서는 휨을 받는 압축강도 80 MPa 수준의 고강도 콘크리트 부재의 구조거동 실험 연구를 수행하였다. 실험변수는 보통(SD 400) 및 고강도(SD 600)철근, 0.98~1.58%의 종방향 철근비, 200×250, 200×300 mm의 단면크기를 고려하였다. 9개의 보 부재를 제작하여 휨 실 험을 수행하였으며 극한휨강도, 하중-처짐 관계, 균열 형태, 파괴형상 및 연성을 파악하였다. 실험결과는 철근비가 증가함에 따라 휨강도는 증 가하고 연성은 감소한다. 또한, 철근비가 증가함에 따라 균열의 개수가 증가하며 균열폭은 감소하는 경향을 나타내었다. 철근의 강도 등급에 따른 하중-균열폭 관계는 뚜렷한 차이를 나타내지 않는다. 콘크리트 비선형거동 해석을 수행하였으며, 극한하중 예측값과 측정값을 비교하였 다. 고강도 콘크리트의 휨거동 예측 결과는 실험부재의 휨강도를 전반적으로 과소평가하고 있다.

Der vorliegende Beitrag behandelt die logische Struktur der hypothetischen Einwilligung im Vergleich mit dem rechtsmässigen Alternativverhalten. Infolge einer mangelhaften Aufklärung wird die Einwilligung zur Unwirksamkeit und ist der Erfolg rechtswidrig. Mit der Ersetzung durch eine ordnungsgemässe Aufklärung wird die Einwilligung zur Wirksamkeit und ist der Erfolg rechtsmässig. Beide Erfolge sind deshalb nicht die gleichen. Die Zurechnung des Erfloges muss daher abgelehnt werden. Auf der Tatbestandsebene sind aber beide Erfolge beim rechtsmässigen Altenativverhalten anders. Die Zurechnung des Erfolges muss also ausgechlossen werden. Die Übertragung der Schlussfolgerung der Tatbestandsebene auf die Rechtswidrigkeitsebene ist deshalb logisch unmöglich. Dies zeigt die logische Unstimmigkeit der Argumentationsfigur der hypothetischen Einwilligung. Die von der koreanischen Rechtsprechung suggerierte Vergleichbarkeit der hypothetischen Einwilligung mit dem rechtsmässigen Alternativverhalten erweist sich also bei näherer Untersuchung aus logischen Gründen als unhaltbar. Von daher behandelt die koreanische Rechtsprechung ohne Grund die Aufklärungspflict als Sorgfaltswidrigkeit. Das Problem ist wieder zurück zur Tatbetandsebene verlagert. Dann stellt sie diese Pflichtwidrigkeitszusammenhang fest mit der Kausalität. Sie versteht diesen Zusammenhang als Kausalzusammenhang. Der Zusammenhang zwischen Aufklärungsmängel und Erfolg ist kein Kausalzusammenhang. Sie sind nur rechtliche Vorraussetzungen und rechtliche Folge.