• 한국BIM학회 논문집
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• 제12권1호
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• pp.23-34
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• 2022

In the current 2D-based design, design reliability is lowered due to interference and inconsistency between plans, errors in drawings and quantities, etc. At the time of transition to BIM-based 3D design, it is necessary to expand the reliability and usability of BIM by eliminating these errors from the design stage through securing the quality of the BIM digital model. Therefore, in the railway infrastructure design stage, the quality management process and standards of the BIM digital model were defined and quality management index were developed. Based on the rule extracted from the quality management index, a pilot quality management was conducted in connection with the commercial Model-Checker rule, problems and improvement plans were derived, and a rule-based automated quality management plan was prepared.

• Smart Structures and Systems
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• 제30권6호
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• pp.583-599
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• 2022

In this paper, a multi-objective wireless sensor network configuration optimization method is proposed. The proposed method aims to determine the optimal information and lifespan wireless sensor network for structural health monitoring of large-scale infrastructures. In particular, cluster-based wireless sensor networks with multi-type of sensors are considered. To optimize the lifetime of the wireless sensor network, a cluster-based network optimization algorithm that optimizes the arrangement of cluster heads and base station is developed. On the other hand, based on the Bayesian inference, the uncertainty of the estimated parameters can be quantified. The coefficient of variance of the estimated parameters can be obtained, which is utilized as a holistic measure to evaluate the estimation accuracy of sensor configurations with multi-type of sensors. The proposed method provides the optimal wireless sensor network configuration that satisfies the required estimation accuracy with the longest lifetime. The proposed method is illustrated by designing the optimal wireless sensor network configuration of a cable-stayed bridge and a space truss.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.373-380
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• 2004

This paper presents the feasibility of an impedance-based damage detection technique using piezoelectric (PZT) transducers for civil infrastructures such as steel bridges. The impedance-based damage detection method is based on monitoring the changes in the electrical impedance. Those changes in the electrical impedance are due to the electro-mechanical coupling property of the piezoelectric material and structure. An effective integrated structural health monitoring system must include a statistical process of damage detection that is automated and real time assessment of damage in the structure. Once measured, damage sensitive features from this impedance change can be statistically quantified for various damage cases. The results of the experimental study on three kinds of structural members show that cracks or loosened bolts/nuts near the PZT sensors may be effectively detected by monitoring the shifts of the resonant frequencies. The root mean square (RMS) deviations of impedance functions between before and after damages were also considered as a damage indicator. The subsequent statistical methods using the impedance signature of the PZT sensors were investigated.

• Journal of Smart Tourism
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• 제2권1호
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• pp.21-31
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• 2022

This review paper aims at providing a systematic analysis of articles published in various journals and related to the uses and business applications of big data. The goal is to provide a holistic picture of the place of big data in the tourism industry. The reviewed articles have been selected for the period 2013-2020 and have been classified into 8 broad categories namely business strategy and firm performance; banking and finance; healthcare; hospitality; networks and telecommunications; urbanism and infrastructures; law and legal regulations; and government. While the categories are reflective of components of tourism industries and infrastructures, the meta-analysis is organized around 3 broad themes: preferred research contexts, conceptual developments, and methods used to research big data business applications. Main findings revealed that firm performance and healthcare remain popular contexts of research in the big data realm, but also demonstrated a prominence of qualitative methods over mixed and quantitative methods for the period 2013-2020. Scholars have also investigated topics involving the notions of competitive advantage, supply chain management, smart cities, but also ethics and privacy issues as related to the use of big data.

• Geomechanics and Engineering
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• 제37권2호
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• pp.189-195
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• 2024

Buried pipelines can be classified as continuous and segmented pipelines. These infrastructures can be damaged either by ground movement or by seismic wave propagation during an earthquake. Permanent ground deformations (PGD) include surface faulting, liquefaction-induced lateral spreading and landslide. Liquefaction is a major problem for both superstructures and infrastructures. Buyukcekmece lake zone, which is the studied region in this paper, is a liquefaction prone area located near the North Anatolian Fault Line. It is an active fault line in Turkey and a major earthquake with a magnitude of around 7.5 is expected in this investigated region in Istanbul. It is planned to be constructed a new 12" steel natural gas pipeline from one side of the lake to the other side. In this study, this case has been examined in terms of two different support conditions. Firstly, it has been defined as a beam in liquefied soil and has built-in supports at both ends. In the other approach, this case has been modeled as a beam in liquefied soil and has vertical elastic pinned supports at both ends. These models have been examined and some solution proposals have been produced according to the obtained results. In this study, based on this sample, it is aimed to determine the behaviors of buried continuous pipelines subject to liquefaction effects in terms of buoyancy.

• International Journal of Internet, Broadcasting and Communication
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• 제16권2호
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• pp.1-9
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• 2024

As the Internet of Things (IoT) continues to permeate every facet of modern life, the imperative to secure this vast and dynamic frontier becomes increasingly paramount. This presents a comprehensive exploration of the challenges and opportunities inherent in safeguarding the interconnected web of IoT devices. The research critically examines the limitations of current cybersecurity measures through an extensive review of diverse topics, including IoT network performance, smart grid security, and the escalating cyber threats against critical infrastructures. A meticulous analysis of research findings underscores the need for enhanced infrastructure and ongoing research to fortify the cybersecurity mechanisms surrounding IoT objects. We underline the imperative of relentless research efforts to parry the advancing threats and leverage the promise of nascent technologies. Our findings affirm the pivotal influence of robust cybersecurity measures in crafting a resiliently connected ecosystem. The paper underscores the importance of ongoing research to address evolving threats and harness the potential of emerging technologies, reaffirming the central role of cybersecurity in shaping a secure interconnected world. In conclusion, the study emphasizes the dynamic and ever-evolving nature of cybersecurity on the IoT frontier. It unveils a complex landscape of challenges, ranging from network performance intricacies to the security concerns of critical infrastructures.

• International Journal of Computer Science & Network Security
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• 제24권9호
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• pp.162-168
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• 2024

VANET (vehicular ad hoc network) refers to the case networks designed for vehicles. Such networks are established among the vehicles which are equipped with communication tools. Within these networks, vehicles are regarded as the network nodes. On time and on schedule transmission of data is of high significance for these networks. In order to accomplish the objective of on-time data transmission, specific electronic equipment is embedded in each vehicle which maintains ad hoc communications among the passengers. Information about traffic, road signs and on-line observation of traffic status can be transmitted via these networks; such data makes it possible for the driver to select the best route to reach his destination. If there are not any infrastructures, two broadcasting approaches can be considered: overflowing and rebroadcasting. The overflowing approach leads to heavy traffic. Hence, the challenge we face is to avoid the broadcasting flood. In this paper, an approach for the management of the broadcasting flood is proposed based on fuzzy theory. The proposed method is assumed to have better performance and efficiency than any other approaches in terms of crash rate, the rate of message success and delay

• 한국지진공학회논문집
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• 제10권6호
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• pp.137-145
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• 2006

최근 건설기술이 발달함에 따라 점차적으로 더욱 높은 정확성과 신뢰성을 바탕으로 구조물의 상태를 파악 또는 예측 할 수 있는 기술적인 체제가 요구되고 있는 시점에서, 광섬유센서는 내구성과 높은 분해능, 전자기파 노이즈 저항성, 절대값의 측정, 다중화 등의 가지고 있는 여러 장점 때문에 미국 등 선진국의 경우 교량, 터널 그리고 건물 등에 변위와 변형률 측정에 많은 설치가 진행되어 왔고, 광섬유 센서를 이용한 시스템이 구조물의 안정성과 잔존수명을 판단하는 기준으로 중요한 역할을 할 것으로 기대되고 있다. 본 논문에서는 이러한 광섬유센서 중에서 일반적으로 가장 많이 사용하고 있는 광섬유격자 센서의 응용의 폭을 확대하기 위하여 여러 가지 응용분야에 적용하고자 하였으며, 특히 전단응력이 많이 걸려 foil형 스트레인 게이지를 사용하기 어려운 보 기둥 접합부에 적용하여 광섬유격자 센서가 일반적으로 사용되는 전자식 변위 센서들과 정밀도가 대단히 차이가 나고 있음을 보여주고 있고, 복합재료와 콘크리트 접합 구조물에 적용하여 흔히 발생하는 결함인 delamination을 측정하는데 광섬유격자 센서가 유효적절함을 보여주고 있으며, 원자력발전소 격납구조물과 같은 대형구조물에 적용하여 변위를 측정함에 있어서 광섬유격자 센서가 시공도 용이하고 데이터도 양호함을 보여 주고 있어, 기존의 어떤 구조물도 광섬유센서를 적용하여 쉽게 광섬유 스마트구조물화 할 수 있음을 보여준다.

• 한국건설관리학회논문집
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• 제18권2호
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• pp.81-90
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• 2017

임진강 유역은 1996년부터 1999년까지 3번의 대규모 홍수가 발생하여 많은 인명피해와 9천억원의 재산피해를 입었다. 우리나라는 기후변화로 인하여 홍수피해가 앞으로 증가할 것으로 예상된다. 본 연구는 기후시나리오를 활용하여 미래의 홍수피해를 예측하고, 실물옵션 기반 경제성분석 방법을 제시하였으며, 임진강유역의 홍수방지시설물 투자사업의 사례연구를 통해 경제성분석을 실시하였다. RCP (Representative Concentration Pathway) 기후시나리오에서 모의된 강수량 자료를 활용하여 홍수피해액을 계산하고, 홍수방지시설물 투자에 의한 저감이익을 분석하였다. 향후 RCP8.5와 RCP4.5 기후시나리오가 실현되는 조건을 가정하여 홍수피해 저감이익의 변동성을 구하고, 2071년에 200년 재현주기에 적응하도록 하는 확장을 위한 투자를 할 수 있는 확장옵션을 적용하여 프로젝트의 옵션가치를 구했다. 옵션가치 분석결과, 두 가지 시나리오 하에서 경제성을 확보하고 있음을 확인하였고, RCP8.5 기후시나리오가 실현될 때가 RCP4.5의 경우보다 홍수피해 저감이익이 더 많이 발생하였다. 본 연구는 정부 의사결정권자가 실물옵션분석방법을 활용하여 홍수방재시설물의 경제성분석에 기후변화 불확실성을 고려할 수 있도록 도와줄 것으로 기대되며, 기후시나리오에서 제공하는 강우자료를 활용하여 기후위험요소를 경제적 가치로 정량화하는 방법을 제시하였다.

• 보건교육건강증진학회지
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• 제24권5호
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• pp.87-101
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• 2007

연구목적: 본 연구는 제조업과 건설업 사업장 노동조합관계자들의 사내 안전보건교육에 대한 인식과 참여정도를 파악하고 이들 간의 관련성을 분석하는데 그 목적을 두었다. 연구방법: 본 연구의 대상은 103명의 노동조합 관계자들(78개 제조업 산업장의 91명, 12지역의 12건설업 노동조합관계자)이었고 이들을 대상으로 자기기입식 설문조사를 실시하였다. 전국기업체산업안전협의회의 회원사들을 중심으로 우리나라 전역의 제조업과 건설업 사업장을 임의로 선정하고 선정된 사업장별로 설문지 2부, 노동부의 설문조사 협조공문, 설문조사 안내문, 설문회수용 봉투로 구성된 우편물을 사업장 노동조합사무실로 배달하는 방식으로 설문조사를 실시하였다. 80% 이상이 소속 사업장 규모가 50인 이상이었고 대부분이 결혼한 남자로 구성되어 있었다. 설문조사 내용은 대상자와 대상사업장의 일반적 특성, 사업장의 안전보건교육 특성, 노동조합의 사내 안전보건교육 참여도, 노동조합의 사내 안전 보건교육에 대한 인식으로 구성되었다. 연구결과: 전체적으로 제조업사업장에 건설업 사업장에서보다 사내 안전보건교육에 대한 인적, 물적 인프라가 잘 구축되어 있었고 사업주의 사내 안전보건교육에 대한 지원도가 높았으며, 사내 안전보건교육 담당자들의 교육역량에 대한 인식도가 더 높은 경향을 보였다. 이러한 인적, 물적 인프라는 사업장내 노동조합의 안전보건교육 참여도와 정의 상관관계가 있었으며 그 정도는 중등도 이상의 수준이었다. 결론: 이상의 결과를 토대로 볼 때, 사업장 안전보건교육에 대한 노동조합의 참여와 지지를 확충하기 위해서는 사업장 조직적으로 안전보건교육 실시에 대한 지원이 선행되어야 함을 알 수 있었다. 아울러 안전보건관리자들을 대상으로 근로자 산업재해에 대한 지식뿐만 아니라 사내 안전보건교육을 수행관리할 수 있는 '교육역량'을 기를 수 있도록 연수프로그램을 확충할 필요가 있겠다.