• Structural Monitoring and Maintenance
• /
• 제2권3호
• /
• pp.283-300
• /
• 2015

Visual condition inspections remain paramount to assessing the current deterioration status of a bridge and assigning remediation or maintenance tasks so as to ensure the ongoing serviceability of the structure. However, in recent years, there has been an increasing backlog of maintenance activities. Existing research reveals that this is attributable to the labour-intensive, subjective and disruptive nature of the current bridge inspection method. Current processes ultimately require lane closures, traffic guidance schemes and inspection equipment. This not only increases the whole-of-life costs of the bridge, but also increases the risk to the travelling public as issues affecting the structural integrity may go unaddressed. As a tool for bridge condition inspections, Unmanned Aerial Vehicles (UAVs) or, drones, offer considerable potential, allowing a bridge to be visually assessed without the need for inspectors to walk across the deck or utilise under-bridge inspection units. With current inspection processes placing additional strain on the existing bridge maintenance resources, the technology has the potential to significantly reduce the overall inspection costs and disruption caused to the travelling public. In addition to this, the use of automated aerial image capture enables engineers to better understand a situation through the 3D spatial context offered by UAV systems. However, the use of UAV for bridge inspection involves a number of critical issues to be resolved, including stability and accuracy of control, and safety to people. SLAM (Simultaneous Localisation and Mapping) is a technique that could be used by a UAV to build a map of the bridge underneath, while simultaneously determining its location on the constructed map. While there are considerable economic and risk-related benefits created through introducing entirely new ways of inspecting bridges and visualising information, there also remain hindrances to the wider deployment of UAVs. This study is to provide a context for use of UAVs for conducting visual bridge inspections, in addition to addressing the obstacles that are required to be overcome in order for the technology to be integrated into current practice.

• 융합정보논문지
• /
• 제12권3호
• /
• pp.11-16
• /
• 2022

국제화에 따라 외국인 유학생 수가 갈수록 많아지고 있지만, 유학생은 학교 방문 초기에 캠퍼스 환경이 낯선 경우가 많다. 본 연구 목적은 외국인 유학생들이 입학한 후에 캠퍼스가 낯설고 학습생활이 불편한 점들을 개선하고자 게임화 기법을 적용한 AR 캠퍼스 안내 App를 설계 및 제작하였다. 제작한 앱은 장소별 학습 목표, 임무(Mission), 및 보상(Reward)를 반영하여 디자인하였다. 공주대학교 재학 유학생에 대한 '캠퍼스 건물 위치정보 인지도 조사'에 따라 6개 표시를 POI(Point of Interest)로 선정하여 사용자가 적극적으로 참여할 수 있도록 적합한 임무 및 문제점을 설계하였다. 사용자는 학교의 중요한 장소를 재미있게 알 수 있을 뿐만 아니라 관련 기기의 사용법도 쉽게 이해 할 수 있게 한다.

• Steel and Composite Structures
• /
• 제17권3호
• /
• pp.253-269
• /
• 2014

Among the various alternatives to make a steel tubular member connection, making a slotted and gusset plate welded connection is one of the most frequently preferred alternatives. This type of connection is essentially an end connection that is made by slotting the tube longitudinally, inserting the gusset plate and then placing longitudinal fillet welds at the tube-to-plate interface. In this paper an experimental study on the behaviour of such connections in stainless steel is presented. 24 specimens were tested under concentrically applied axial tensile forces for varying tube-to-gusset plate weld lengths. Both circular and box section members were considered in the test program. Load-deformation curves were obtained and comparisons were made in terms of strength and ductility. The results obtained from the study were then critically examined and compared with currently available design guidance for slotted gusset plate welded tubular end connections. It is noted that no specific rules exist in international specifications on structural stainless steel which cover the design of such connections. Therefore, the results of this study are compared with the existing design rules for carbon steel.

• Advances in aircraft and spacecraft science
• /
• 제10권4호
• /
• pp.317-334
• /
• 2023

This paper presents a basic methodology and a set of numerical tools for the preliminary design of solid-fueled ramjet missiles. An elementary code determines the baseline system configuration comprised of warhead, guidance-control, and propulsion masses and geometries from specific correlations found in the literature. Then, the system is refined with the help of external and internal ballistics codes. Equations of motion are solved for the flight's ascending, cruising, and descending stages and the internal ballistic set of equations designs the ramjet engine based on liquefying fuels. The combined tools sized the booster and the ramjet sustainer engines for a long-range missile, intended to transport 200 kg of payload for more than 300 km range flying near 14,000 m altitude at Mach 3.0. The refined system configuration had 600 mm in diameter and 8,500 mm in length with overall mass of 2,128 kg and 890 kg/m3 density. Ramjet engine propellant mass fraction was estimated as 74%. Increased missile range can be attained with paraffin-polyethylene blend burning at near constant regression rate through primary air mass flow rate control and lateral 2-D air intakes.

• 디지털융복합연구
• /
• 제17권7호
• /
• pp.49-58
• /
• 2019

본 연구의 목적은 인터넷전문은행의 국내 연구 현황을 분석하고, 향후 연구 방향을 제시하는 것이다. 이를 위해 본 연구에서는 먼저, 인터넷전문은행의 기본 개념과 현황을 간략히 정리하고, 문헌 분석 기준을 수립하고, 수립한 기준을 바탕으로 인터넷전문은행에 관련된 56편의 문헌을 분석하였다. 인터넷전문은행 분야의 학술적인 연구와 실무에서 참고할 수 있는 주요한 연구 결과와 향후 연구방향을 요약하면 다음과 같다. 첫째, 연구 방법적으로 비실증 연구는 의견/주장보다는 수학적/개념적 모델 수립의 연구를, 실증 연구의 경우에는 2차 데이터 분석 방법을 활용하고, 둘째, 개인수준의 연구의 경우, 은행 인력에 대해 연구와 고객 대상의 연구에서 활용과 성과에 대한 심도 있는 연구가 필요하고, 셋째, 조직 단위의 연구 활성화가 필요하고, 넷째, 사회 수준 연구에서는 인터넷전문은행의 파급효과를 보다 체계적으로 분석할 필요가 있다고 판단된다.

• Steel and Composite Structures
• /
• 제9권2호
• /
• pp.173-189
• /
• 2009

This paper presents a study on the behavior and design of bolted stainless steel plates under in-plane tension. Using an experimentally validated finite element (FE) program strength of stainless steel bolted plates under tension is examined with an emphasis on plate bearing mode of failure. A numerical parametric study was carried out which includes examining the behavior of stainless steel plate models with various proportions, bolt locations and in two different material grades. The models were designed to fail particularly in bolt tear-out and material piling-up modes. In the numerical simulation of the models, non-linear stress-strain material behavior of stainless steel was considered by using expressions which represent the full range of strains up to the ultimate tensile strain. Using the results of the parametric study, the effect of variations in bolt positions, such as end and edge distance and bolt pitch distance on bearing resistance of stainless steel bolted plates under in-plane tension has been investigated. Finally, the results obtained are critically examined using design estimations of the currently available international design guidance.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2012년도 추계학술발표대회
• /
• pp.1531-1534
• /
• 2012

모델기반 아키텍처 MDA (Model Driven Architecture)는 소프트웨어 개발의 추상화 수준을 높이기 위한 최근의 개발 아키텍처이며 완벽한 이해성을 확보하기 위해서 구체적인 구현기술은 반드시 개발자에게 추상적으로 (encapsulation) 숨겨져야 한다. 즉, 개발자는 자동적으로 실행 가능한 시스템으로 변환하는 플랫폼에 구애 받지 않는 모델들 PIM(Platform Independent Model)만을 고려하게된다. 본 논문에서는 MDA 를 캠퍼스 안내 앱에 적용하여 개발함으로써 모바일 디바이스 및 OS 에 독립된 어플리케이션을 개발 방법론을 제시한다.

• 한국산학기술학회논문지
• /
• 제17권4호
• /
• pp.283-295
• /
• 2016

본 연구는 전북소재 4년제 대학교 6개를 선정하고, 각 대학의 편의시설을 매개시설, 내부시설, 위생시설, 안내 및 기타시설로 나누고 각 시설이 편의증진법의 세부기준에 적합한지를 조사하였다. 그 결과 대학교 편의시설은 전반적으로 편의증진법 기준에 미치지 못하는 수준이었으며, 편의증진법 기준에 맞더라도 이용의 불편함과 관리 부족 등으로 인해 장애학생들에게 적합한 환경을 제공하지 못하는 것으로 평가되었다. 본 연구결과를 통한 대학 내 보편적 설계에 기초한 편의시설의 기준 적합도를 높이며, 수요자 중심의 고등고육환경 발전을 위한 편의시설 개선과 확충을 위한 논의점이 제시되었다.

• Educational Technology International
• /
• 제6권1호
• /
• pp.41-63
• /
• 2005

E-Learning is widely introduced with cyber universities in Korea from 2001 whencyber universities were first authorized by the Ministry of Education and Human Resource Development. E-learning amplified by cyber university gave a big impact in the campus based university which became the cause for the educational paradigm shift. The changes of status of cyber university shows important trend in college education which was analyzed by enrollment rate, types of cyber university, demography, and study areas. The enrollment rate of cyber universities is ever since 2001 and variety of study areas gives popularity to students. The demography of students is as expected older than traditional students. Female students at the cyber university outnumbered that at campus based university in Korea. For analyzing the trend of e-learning in Korea, there were studies twice in 2001 May-June from 213 faculty members and staff, 630 students and in 2004 May-June with 401 students. Most of e-learning students tent to spend less time yet, students feel more burden with e-learning. Professors tend to load more materials for the e-learning in 2001but in 2004 study, the difference no longer exists. Professors and students feel the academic achievement through e-learning is not as good as from the traditional classes. Difficulties for e-learning in 2001 were the lack of administrative information but in 2004, boring contents and lack of instructional strategies for e-learning. Technical problems still do exist but less serious. Suggestions for e-learning are blended learning, online students prefer video streaming with their own lecturer, new definition of instructor is needed, professional development for content development and online instruction is needed, success story of online learning should be encouraged, guidance for online students needed. The cyber university experiencegave a positive impact on the traditional universities such as rethinking the roles of universities, the quality control of classes, professional development, student oriented educational service of e-learning pedagogy.

• 융합정보논문지
• /
• 제10권10호
• /
• pp.246-252
• /
• 2020

치위생 전공 학생을 대상으로 학업적 자기효능감, 주관적 행복감이 학업 탄력성에 어떠한 영향을 미치는지 파악하여 치위생 전공 학생 지도 및 대학생활 적응에 도움을 주고자 시행하였다. 2020년 4월부터 6월까지 2개월 동안 대전·충남 지역의 치위생 전공 학생을 임의추출하여 자기기입식 설문조사를 시행하였고, 총 175명을 최종분석하였다. 연구결과 학업 탄력성에 영향을 주는 요인은 주관적 행복감, 학업적 자기효능감이었고, 그 중 가장 영향을 주는 요인은 주관적 행복감이었으며, 설명력은 25.6%였다. 치위생 전공 학생 지도 및 대학생활 적응과 관련된 요인을 제시함으로써 대학생활 적응에 관련된 프로그램 개발에 도움을 줄 수 있는 기초자료로 활용할 수 있을 것으로 생각된다.