• Steel and Composite Structures
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• 제8권1호
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• pp.85-98
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• 2008

In this study the progressive collapse potential of three- and nine-story special steel moment frames designed in accordance with current design code was evaluated by nonlinear static and dynamic analyses. It was observed that the model structures had high potential for progressive collapse when a first story column was suddenly removed. Then the size of beams required to satisfy the failure criteria for progressive collapse was obtained by the virtual work method; i.e., using the equilibrium of the external work done by gravity load due to loss of a column and the internal work done by plastic rotation of beams. According to the nonlinear dynamic analysis results, the model structures designed only for normal load turned out to have strong potential for progressive collapse whereas the structures designed by plastic design concept for progressive collapse satisfied the failure criterion recommended by the GSA guideline.

• Geomechanics and Engineering
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• 제35권5호
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• pp.465-473
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• 2023

The higher order shear deformable model and an exact analytical method is used for analytical bending analysis of a cylindrical shell subjected to mechanical loads, in this work. The shell is modelled using sinusoidal bivariate shear strain theory, and the static governing equations are derived using changes in virtual work. The eigenvalue-eigenvector method is used to exactly solve the governing equations for a constrained cylindrical shell The proposed kinematic relation decomposes the radial displacement into bending, shearing and stretching functions. The main advantage of the method presented in this work is the study of the effect of clamping constraints on the local stresses at the ends. Stress, strain, and deformation analysis of shells through thickness and length.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.213-218
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• 2001

VR (Virtual reality) technologies have given engineers the ability to design, test, and evaluate engineering systems in a virtual environment. The virtual plant is the highlight of the application of the VR technology to plant engineering. Plant design, maintenance, control, management, operation are integrated in the virtual plant. The VR monitoring system including the concept of the virtual plant is developed to replace a current control room that has number of gages and warning lamps in two-dimensional panels which shows the operating status of a plant. The operating status of the plant is displayed in the VR monitoring system through the realistic computer graphics. Sophisticated, realistic and prompt control becomes possible. The VR monitoring system consists of advanced visualization, walk-through simulation and navigation. In the virtual environment, a user can navigate and interact with each component of a plant. In addition, the user can access the information by just clicking interesting component. The VR monitoring system is operated with various modules, such as (1) virtual plant constructed with Graphic Management System (GMS), (2) Touch & Tell System, and (3) Equipment DB System of Part. In order to confirm the usefulness of the VR monitoring system, a pilot gas plant which is currently being used for plant operator training is taken as application. The end of the paper gives an outlook on the future work and a brief conclusion.

• 대한토목학회논문집
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• 제33권6호
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• pp.2509-2518
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• 2013

증강현실(Augmented Reality, AR) 기술은 현실 환경을 기반으로 컴퓨터에서 생성한 가상의 객체정보를 중첩해봄으로써 가상현실 상에서 느낄 수 없는 실감형 모델을 구현하는 기술이다. 본 연구에서는 토목공사 철근배근 작업에 증강현실 기술을 적용하는 방법론과 시스템 시제품을 구성하여 철근공사 작업의 증강현실 적용성을 검증하고 있다. 토목공사 현장의 여러 작업들 중에서 철근공사는 절차화된 매뉴얼방식보다는 숙련공의 경험적 방식에 의해 작업이 진행되는 대표적 공정이다. 이러한 공정에 증강현실을 적용하면 당초 계획도면과 비교하여 누락된 철근배근 및 상이한 배근 상태를 시각화하여 계측할 수 있으므로 시공성을 향상시킬 수 있다. 구축된 시스템은 3차원으로 모델링 된 철근객체를 실제 시공현장에 중첩하여 시각화함으로써 철근 조립공정들의 작업 이해도를 높이고, 검측단계에 활용함으로써 철근조립작업에서 발생할 수 있는 하자와 재작업으로 인한 비용증가를 억제할 수 있을 것이라 기대된다.

• 한국실내디자인학회논문집
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• 제40호
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• pp.158-164
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• 2003

The rapid development of information technology has much influence on architectural design. Collaboration beyond time and space has been possible by networking the work environment and digital products. Thus, the virtual design studio on architectural design is getting more important than ever before. This research investigates a virtual design studio methodology for effective collaboration. The building design process and the communication model are studied and possible modes of design collaboration are defined. This paper proposes an internet-based Virtual Reality(VR) communication tool as well as new design methodology that we call the 'Hybrid Design Methodology'. We expect that this design methodology will dramatically increase design feedbacks, and thus results in better design alternatives. There are two issues involved in developing the collaborative virtual design studio: 1) an intuitive interface that presents collaborative relations, and 2) three-dimensional computer-mediated communication tool using sketch as a modeling method. Further research issues identified at the end of the research include developing algorithms that translate mapping images to polygons for the drafting phase in the design process.

• International Journal of Contents
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• 제11권1호
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• pp.21-30
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• 2015

A simulated realistic virtual environment is inhabited by autonomous cyber-humans who play the roles of agents in events. A key element, which enables this realism, is the historical context formed by time and space. A knowledge-representation scheme, composed of both spatial and temporal aspects needed by the agent to respond to dynamically changing situations, is essential for the design of a realistic virtual agent. In this work, spatial and temporal aspects of dynamic situations in the virtual environment have been formalized as a key component of our knowledge-representation scheme. This scheme provides a mathematical framework to construct realistic virtual situations that change with time, and background knowledge for agents in the simulated environment to deduce new pieces of information and plan against changing situations.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.373-375
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• 2009

This paper introduces the concept of Tangible Shopping conducting in virtual world. The main idea of this paper is to combine the concept of web 2.0 mashup into shopping activities in virtual world. Feature of annotation and web browsing are also included in this concept. This research aims to enhance web shopping activities from the conventional approach into new way which deliver tangible shopping experiences to users. At the beginning, we review the state-of-the-art of virtual worlds and Web 2.0 Mashup. Next, we review our related work. Then, we address the design and implementation of tangible shopping in virtual worlds.

• 한국정밀공학회지
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• 제17권7호
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• pp.63-73
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• 2000

Internet becomes very common tool for communication and data sharing. Virtual reality(VR) on web browser, and virtual prototyping and virtual manufacturing is widely used in many engineering folds. The reduction of overall development process and error minimization during data conversion becomes very crucial where sharing data via Internet and VR. This paper deals with the advantage and disadvantage of VRML format used in RP(Rapid Prototyping), and a software for RP data preparation is developed. If VRML format as an international standard for VR, is replaced with STL format, the weak points of STL format can be overcome and the technique related to virtual prototyping and virtual manufacturing can be addressed more systematically by sharing the data. The system developed in this work shows a good window to get access to a more realistic observation of an object fur an RP system from a long remote sites in a more systematic way.

• 한국컴퓨터정보학회논문지
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• 제22권7호
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• pp.83-91
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• 2017

In this paper, we propose a thorough solution for adjusting virtual sound field with different kinds of devices and software in preliminary procedure and late stage of music processing. The basic process of music production includes composing, arranging and recording at pre-production stage as well as sound mixing and mastering at post-production stage. At the initial stage of music creation, it should be checked whether the design of virtual sound field, the choice of the tone and the instrument used in the arrangement match the virtual sound field required for the final work. In later recording, mixing and mastering, elaborate adjustments should be done to the virtual sound field. This study also analyzed how to apply the parameter of the effectors to the design and adjustment of the virtual sound field, making it the source of our creation.

• 한국CDE학회논문집
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• 제14권1호
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• pp.42-49
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• 2009

Virtual manufacturing technology has been applied in actual production sites with the development of virtual reality technology. However, the current virtual manufacturing technology requires experts for application of the system. Furthermore, the sense of reality is diminished as the entire simulation is driven by virtual objects. In contrast, mixed reality can visualize virtual objects and an actual work place simultaneously, and thus the sense of reality of the virtual manufacturing simulation can be improved. This paper introduces a method that applies mixed reality in the manufacturing process, and proposes a method to adapt general safety sign post in the factory instead of a black square marker for visual fiducial recognition.