• Proceedings of the KWS Conference
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• 2004.05a
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• pp.54-56
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• 2004

확실한 아크개시는 자동화 GMAW공정에서 매우 중요하다. 자동차 조립산업 및 부품사업 분야의 아크용접 현장에서는 대부분 박판에 짧은 비드로 용접하는 경우가 많기 때문에 아크개시가 더욱 중요시된다. (중략)

• Korean Journal of Construction Engineering and Management
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• v.9 no.2
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• pp.108-116
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• 2008

At present, construction automation is a critical solution for the shortage of labor and the aging of skilled workers. Especially, researches for transportation automation are achieved to improve the efficiency as the construction of tall-building construction. Transportation automation needs to control the swung member by the inertia and/or the wind-force at the end of cable. However, previous to control, the presupposition of the swing is heavily difficult work because the inertia and the wind force are irregularly changable according to work condition. Therefore, in this study, dynamic modeling of crane and simulation was performed to find the characteristic of the swing. In the result, the maximum displacement of the swung material was analyzed. And, on the basis of analysis, the criteria to decide workability of automated transportation considering the material size and the wind force onsite was proposed.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.242-246
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• 2006

최근 들어 전 세계적으로 유량측정 분야의 큰 변화의 방향은 자동화이다. 전자, 전기 기술과 정보통신 기술의 발달을 유량측정 분야에 적용하여 자동적으로 유량측정을 수행하고 실시간으로 모든 유량자료를 수집하는 시스템을 구성하려는 연구가 활발하게 진행중이다. 최근에 초음파 유량계와 더불어 자동 유량측정 기법으로 각광을 받고 있는 기법이 유속지수법(index velocity method)이다. 유속지수법의 원리는 매우 간단하다. 수위 기록을 통하여 수위-면적 관계로부터 흐름 단면적을 구하고, 임의의 영역에서 측정된 유속이 단면 평균 유속으로 환산될 수 있다면, 흐름 단면적과 평균 유속에 의해 연속적으로 유량을 구할 수 있다. 유속지수법에서 가장 중요한 것이 전체 평균 유속을 대표할 수 있는 유속지수를 정확하고 효율적으로 측정하는 것이다. 유속지수법에 의한 연속 유량측정 목적으로 최근에 ADVM(Acoustic Doppler Velocity Meter)이 개발되어 이용되고 있다. ADVM은 수중에 초음파를 발사해서 산란체에서 반사되어 돌아오는 초음파의 주파수 편이, 즉 도플러 효과를 이용하여 유속을 측정하는 유속계이다. 본 연구에서는 ADVM을 괴산댐 하류에 위치한 시험하천에 설치하여, 유속지수법에 의한 유량측정기법을 적용하고 그 특성을 분석하였다. 유속지수법으로 측정된 유량을 괴산댐 방류량과 비교한 결과 평균 4.0%의 상대오차를 지니고 있어 비교적 정확한 연속 유량측정이 가능한 것으로 나타났다. 이와 같은 유속지수법을 하천 유량측정에 활용하면 보다 정확한 유량을 연속적으로 자동화하여 측정할 수 있을 것으로 기대된다.연계모형의 한계로 인하여 두 모형의 통합모형이 필요하다. 즉, 강우 혹은 월류유량으로 발생한 지표유량 중 일부분이 과부하가 발생하지 않는 유입구 지점을 통과할 때 배수시스템으로 유입되는 것을 고려할 수 있고, 유입된 유량은 배수시스템 내의 흐름에 반영되도록 배수시스템과 침수해석모형을 통합한 모형 개발이 필요하다. 그러기 위해서는 지표면과 배수시스템에 대한 수리학적 관계를 정립하여야 한다. 본 연구에서는 배수시스템 해석 모형과 도시침수해석 모형을 통합하고, 두 모형간의 유량의 전송과정을 수리학적 관계를 고려한 dual-drainage 도시침수해석모형을 개발하였다. 이를 위해 도시지역 배수시스템 해석 모형으로 널리 이용되고 있는 SWMM모형을 이용하여 지표면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기

• Composites Research
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• v.36 no.2
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• pp.108-116
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• 2023

In this paper, kinematic design and multi-body dynamics analysis were conducted to develop a small manipulator platform for automating the maintenance of structures made of composite materials. To design manipulator kinematically, the existing composite repair process was considered. The 3D design was conducted after selecting the basic specifications of manipulator and end-effecter in consideration of the patch lamination process for repair. Then, variables necessary for simulation and control were generated in MATLAB through inverse kinematic analysis. To evaluate the structural stability of platform, multibody dynamics analysis was conducted using Altair Inspire and Optistruct. Based on the simulation conducted in Inspire, multibody dynamics analysis was conducted in Optistruct, and structural stability was verified through the results of maximum displacement and Von-Mises stress over time. To verify the design, manufacturing and controlling of platform were conducted and compared with the simulation. It was confirmed that the actual repair process path and the simulation showed a good agreement.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.2
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• pp.127-133
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• 2015

In this study, an analytical model was developed for one-dimensional finite element analysis (1D FEA) of a spindle system of machine tools and then implemented to automate the FEA as a tool. FEA, with its vibration characteristics such as natural frequencies and modes, was performed using the universal FEA software ANSYS. VBA of EXCEL was used to provide the programming environment for its implementation. This enabled graphic user interfaces (GUIs) to be developed to allow interactions of users with the tool and, in addition, an EXCEL spreadsheet to be linked with the tool for data arrangement. The language of ANSYS was used to develop a code to perform the FEA. It generates an analytical model of the spindle system based on the information at the GUIs and subsequently performs the FEA based on the model. Automation helps identify the near-optimal design of the spindle system with minimum time and efforts.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.288-291
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• 2008

Recently, the importance and necessity of engineering analysis has shown a steady growth. However, researchers working in small and medium enterprises know little about the usefulness of engineering analysis and suffer from lack of technical knowledge. Axial fan is air fluid machinery in various fields of industry such as automobile, electric appliance, and heavy machinery. It is also a time and budget consuming equipment to develop the axial fan through physical experiments. In order to overcome this problem, we have designed and developed a web-base automated simulator for axial fan's fluid analysis using supercomputer. Automated simulator means that all of processes for engineering analysis including pre-process, solving, and post-process can be performed automatically without user intervention after transferring fan model(CAD files) made by user. After executing the simulator with some parameters, user can receive the report including pressure P and flow rate Q. In this paper, we introduce the architecture of our easy and efficient automated engineering analysis simulator, related techniques and result of development.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.3
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• pp.7-15
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• 2006

Aerodynamic analysis of an airfoil in the transonic region was automated in order to enable parametric study by using the journal file of the commercial analysis code FLUENT, pre/post process Gambit and computational mathematics code MATLAB. The automated capability was illustrated via NACA 0012 and RAE 2822 airfoils. This analysis was carried out at Mach numbers ranged from 0.70 to 0.80, angles of attack; 1$^{\circ}$, 2$^{\circ}$ and 4$^{\circ}$, Reynolds numbers; 4.0${\times}$106, 6.5${\times}$106. The analysis results of a pressure coefficient were verified by comparing with the experimental data which were measured in terms of chord length because the pressure coefficient of an airfoil surface is a good estimator of flow characteristics. The results of two airfoils show that this analysis code is useful enough to be used in the design optimization of airfoil.

• Korean Journal of Construction Engineering and Management
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• v.13 no.4
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• pp.48-59
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• 2012

Gangform, compared to the traditional forms, is a systemized form which can reduce construction duration and cost by the advantage of using it repeatedly. However, transportation and climbing process of the Gangform is highly dependant on the performance of tower crane. Gangform climbing process takes one day out of six to seven days of a structural work cycle. Tower cranes can not be used in other lifting works when they lift the Gangform during the structural work cycle, causing the delay in the construction project. Numerous efforts and researches have been done in domestic and international industry to solve such limitations of Gangform climbing process. Especially, "A Study on the Development of Automatic Gangform Climbing System for Apartment Housing Construction"has suggested a conceptual model which can climb the Gangform system without a tower crane. In this paper, the technical and economical feasibilities of previously proposed Automatic Gangform climbing system are examined by evaluating its structural stability and lifting load reduction effect.

• KIPS Transactions on Computer and Communication Systems
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• v.11 no.5
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• pp.157-166
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• 2022

Exercise is necessary for a healthy life, but it is recommended that it be conducted in a non-face-to-face environment in the context of an epidemic such as COVID-19. However, in the existing non-face-to-face exercise content, it is possible to recognize exercise movements, but the process of interpreting and providing feedback information is not automated. Therefore, in this paper, to solve this problem, we propose a method of creating a formalized rule to track the contents of exercise and the motions that constitute it. To make such a rule, first make a rule for the overall exercise content, and then create a tracking rule for the motions that make up the exercise. A motion tracking rule can be created by dividing the motion into steps and defining a key frame pose that divides the steps, and creating a transition rule between states and states represented by the key frame poses. The rules created in this way are premised on the use of posture and motion recognition technology using motion capture equipment, and are used for logical development for automation of application of these technologies. By using the rules proposed in this paper, not only recognizing the motions appearing in the exercise process, but also automating the interpretation of the entire motion process, making it possible to produce more advanced contents such as an artificial intelligence training system. Accordingly, the quality of feedback on the exercise process can be improved.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.2
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• pp.75-83
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• 1995

As a basic research for the automation of plate forming process, the theoretical aspect of plate bending by line heating was surveyed and numerical simulation of plate bonding deformation was performed using the 3-dimensional nonlinear transient thermal elasto-plastic finite element analysis. Analyzing the unsteady heat conduction problem of the flat steel plate under heat flux input by gas torch, the time history of 3-dimensional thermal distribution was obtained. Transient thermal deformation process of the plate was analyzed under the thermal loading. And the calculated results are investigated in detail.