• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7377-7384
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• 2015

Agricultural tractors must have a function of ROPS to protect drivers under roll-over accident. In this study, finite element analyses and an optimal design were performed to reduce the cost and the production period of the cabin frame of a tractor to pass the ROPS strength test. To confirm the pass of ROPS strength test of an initial design model, the results of deformation and principal strain from the analyses were evaluated. To reduce the weight of the cabin frame, design of experiment of Taguchi was implemented, and an optimal design was obtained. The weight of the optimal design model was reduced by 7% comparing with the initial design model.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.3
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• pp.283-289
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• 2015

In this study, the lightweight design of a brake bracket for a composite bogie was studied by considering two brake bracket models with thicknesses of 12t and 9t, respectively. For achieving this goal, finite element analysis and topology optimization were conducted. Firstly, the largest cross-sectional areas of the vertical and horizontal plates of the brake bracket were selected as the design variables. As the constraint, the Z-axis displacement of the brake bracket was increased by 2.5 units from the initial displacement value. The minimum volume fraction of the design regions was chosen as the objective function. The full model comprised a composite bogie frame and brackets attached together. However, to reduce the analysis time, 1D beam elements were used instead of the composite bogie frame by ensuring its equivalence with the full model. The result revealed that the weights of the 12t and 9t models of the brake bracket were reduced to 60 kg and 31 kg, respectively.

• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.89-95
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• 2017

LCD robot vertical frame lets a arm assembly with glass substrate move up and down, so it must have high stiffness and strength. We applied new manufacturing process by using design optimization process such as topology and size optimization in order to satisfy the request of high stiffness and light weight. The proposed model should be evaluated for endurance strength. Therefore fatigue assessment for weak point of aluminum welding area of vertical frame studied with hot spot stress approach. And the actual stress measuring from test was compared and evaluated with the dynamic stress calculated from multi-body dynamics considering flexible body.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.155-161
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• 2019

Electroencephalography (EEG), a representative method of identifying temporal and spatial changes in brain activity, is a voluntary electrical activity measurable in the human scalp. Various interface technologies have been provided to control EEG activity, and it is possible to operate a machine such as a wheelchair or a robot through brainwaves. The characteristics of EEG data are collected in various types of channels in real time, and a server system for analyzing them is required to have an independent and lightweight system for the platform. In these days, the Spring platform is used as a large business server as an independent, lightweight server system. In this paper, we propose an EEG analysis system using the Spring server system. Using the proposed system, the reliability of EEG control can be enhanced, and analysis and control interface expansion can be provided in various aspects such as game and medical areas.

• Journal of Platform Technology
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• v.10 no.4
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• pp.39-46
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• 2022

Recently, digital contents including video and sound are created in various fields, transmitted to the cloud through the Internet, and then stored and used. In order to utilize digital content, it is essential to verify data integrity, and it is necessary to ensure network bandwidth efficiency of verified data. This paper describes the design and implementation of a server that maintains, manages, and provides data for verifying the integrity of video data. The server receives and stores image data from Logger, a module that acquires image data, and performs a function of providing data necessary for verification to Verifier, a module that verifies image data. Then, a lightweight Merkle tree is constructed using the hash value. The light-weight Merkle tree can quickly detect integrity violations without comparing individual hash values of the corresponding video frame changes of the video frame indexes of the two versions. A lightweight Merkle tree is constructed by generating a hash value of digital content so as to have network bandwidth efficiency, and the result of performing proof of integrity verification is presented.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2610-2615
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• 2010

This paper proposes an object-oriented software development guidance and an evaluation index for the productivity related to Spring 2.5 and Seam 2.0 framework. Lightweight container architecture, such as the EJB, but not heavy, to provide all of the architecture is possible. Currently in production until the lightweight container architecture, known most commonly used architecture framework is Spring and Seam. However, there is no comparison research about the performance of Spring 2.5 and Seam 2.0 framework with same identical platform. In this study, the Java Pet Store blueprint application development platform environment based on the same ordering system JPetStore Spring 2.5 and Seam 2.0 is in the design and implementation. In addition, comparison and standardization of software development productivity assessment is to provide guidance.

• Journal of Digital Convergence
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• v.10 no.3
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• pp.149-154
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• 2012

This paper aims to design and realize android smartphone mobile webapp office JPetStore order system based Seam framework. Currently in production until the lightweight container architecture, known commonly architecture is Seam framework. However, there is no design and implementation research of mobile webapp office with the Seam framework environment. In this study, the Seam environment based on the android mobile webapp office JPetStore order system implementation after analyzing the mobile webapp office development productivity with the objective is to provide guidance.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.6
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• pp.271-276
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• 2018

Based on the service design processes, we examined the market conditions and the criteria to be considered in selecting materials and selected CFRP CNT materials in the development of bicycle design. This material was used to develop frame design among the bicycle parts. The bicycle frame, designed with CFRP CNT material through vibration attenuation testing, tensile strength testing, and stiffness test results before prototype production, shows better results than the bicycle frame manufactured with conventional CNT materials in terms of function.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.651-654
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• 2008

상황인지(Context-awareness)란 사용자의 상황을 인지하여 이를 통해 사용자에게 적합한 최적의 정보를 제공하는 것으로 현재 많은 연구가 진행되고 있다. 이미 상황인지를 위한 프레임워크들이 존재하지만, 작은 메모리가 요구되는 제한적인 하드웨어 상황에서 적용하기에 적합하게 설계된 프레임워크는 흔하지 않다. 이에 대한 문제점을 인식하여 하드웨어 리소스가 부족한 상황에서 빠르게 동작할 수 있는 프레임워크를 구상하여, 기존과는 다른 제한적인 환경 안에서 상황인지를 통해 사용자에게 맞는 최적의 서비스를 판단, 제공하는 모바일 오브젝트를 설계하였다.

• Journal of Internet Computing and Services
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• v.10 no.4
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• pp.127-138
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• 2009

Mobile web applications are being used and changed rapidly due to the growth of mobile device performance. But, cost of development environment and standards make the high development cost and low productivity. It is main reason that the design and implementation of the applications are more time consuming than general computing environments. In this paper, we propose MWeb(MobileWeb)-Framework based on the agile methodology and Ruby on Rails that is a kind of framework for supporting mobile web application development using mobile web standards. This work consists of the mobile web development architecture and agile process model. MWeb-Framework will support the same user experience to the different devices. We validates the framework by implementing the case studies through suggested mobile web development framework. As a result, we can develop the mobile web applications with productivity and quality. In the future, we will suggest how to make the MWeb-Framework standardization and practically apply the frameworks the various case studies to improve framework potentially problems.