• Journal of Communications and Networks
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• v.10 no.4
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• pp.403-411
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• 2008

Energy consumption has been mostly neglected in network coding (NC) research so far. This work investigates several different properties of NC that influence the energy consumption and thus are important when designing NC systems for battery-driven devices. Different approaches to the necessary implementation of coding operations and Galois fields arithmetic are considered and complexity expressions for coding operations are provided. We also benchmark our own mobile phone implementation on a Nokia N95 under different settings. Several NC strategies are described and compared, furthermore expressions for transmission times are developed. It is also shown that the use of NC introduces a trade off between reduction in transmission time and increase in energy consumption.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.1090-1095
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• 1992

This paper describes the systematic control method of process information transfer and machine cell control in FMS implementation. We have constructed an experimental FMS computer network and control system. The system hardware consists of host computer to manage process data and information transfer of machine cells, cell control computers to control machine cells(NC lathe, machining center). On the other hand, software is made up of oredr management module, NC program searching and generation module, NC part program error check module and cell control module. In this study, we could arrive at conclusion as following : The first, each task could be accomplihed by the efficient information transfer in hierachical computer network. The second, data base system of part programs and process control data is needed for the efficint information transfer and production management. Lastly, expansion of FMS control system could be achieved by the hierachical and decentralized computer control system.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.279-284
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• 1988

In this paper, NCTOP is an interactive NC auto programming system for two-dimensional machining. NCTOP consists of seven modules, that is pattern form input, free form input, AutoCAD interface, logic processing, postprocessor processing, output, and database upgrade module. The geometry information of a workpiece to be machined is put into NCTOP program. Then it generates NC program which is final output. NCTOP uses the machining dates from the data base.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.887-891
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• 1992

In this study, it is developed the interactive DNC(Direct Numerical Control) system, in using RS-232C cable and auxiliary computer, through the diagnosis of planning process and information evaluation. this DNC system recognize the Manufacturing planning and control it. This DNC system has a different notation. It can be done by an operator who hasn't knowledge about personnel computer. It is operated with automatic planning and measurement tec. by operator, using part program on the NC(Numerical Control).

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.1078-1083
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• 1992

Extracting the process planning information from the CAD data is the key issue in integrated CAD/CAM system. In this paper, we develop algorithms for extracting the shape and setup configuration for NC machining of prismatic parts. In determining the workpart shape, the minimum-enclosing condept is applied so that the material waste is minimized. To minimize the number of setups, feature based algorithm is developed considrint the part shape, tool shape, and tool approach direction. The validity and effectiveness of the developed algorithms were tested by computer simulations.

• Korean Journal of Computational Design and Engineering
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• v.10 no.4
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• pp.225-236
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• 2005

The primary goal of the study is to provide a newly refined data model, an information exchange foundation of modeling operation for rapid prototyping, as one among non-milling STEP-NC modules. The previous data model has been first modified and refined by reflecting specific user requirements. Second, subsidiary information such as fabrication history as well as traditional process information has been introduced into the newly refined model in order to consolidate the model functionality. In short, the main contribution of the study is to provide a foundation where a newly refined data model is utilized easily and conveniently for practical rapid prototyping fabrication within the newly constructed STEP-NC environment.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.829-832
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• 2003

본 논문은 판재를 다루는 제조업에서 제품생산에 필요한 부재 절단작업도와 NC절단기 제어용 부재 절단 NC 데이터파일을 생성해 주는 네스팅시스템을 웹상에서 구현하고 이를 유료로 활용할 수 있도록 지원하는 인터넷 비즈니스의 한 방법을 제안한다. 웹에서 운용되는 네스팅시스템은 비주얼스튜디오 닷넷(VS.NET)을 개발툴을 사용하며 서버의 과부하를 최소화하고 클라이언트를 최대한 활용할 수 있도록 NEST서버, NEST 클라이언트, 데이터베이스서버 그리고 이들을 연결해주는 커뮤니케이션 인터페이스로 구성되어 있다. NEST 서버에서는 부재의 자동배치기능, 부재의 NC 절단데이터 생성을 위한 CAM기능, NC 포스트프로세서기능이 실행되며 NEST 클라이언트에서는 부재 및 판재 정의기능, 부재 반자동배치기능, 각종 결과의 출력기능 등이 수행된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.5
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• pp.1944-1956
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• 2021

This paper considers a cellular two-way relay network with one base station (BS), one relay station (RS), and two users. The two users are far from the BS and no direct links exist, and the two users exchange messages with the BS via the RS. A non-orthogonal multiple access (NOMA) and network coding (NC)-based decode-and-forward (DF) two-way relaying (TWR) scheme TWR-NOMA-NC is proposed, which is able to reduce the number of channel-uses to three from four in conventional time-division multiple access (TDMA) based TWR approaches. The achievable sum-rate performance of the proposed approach is analyzed, and a closed-form expression for the sum-rate upper bound is derived. Numerical results show that the analytical sum-rate upper bound is tight, and the proposed TWR-NOMA-NC scheme significantly outperforms the TDMA-based TWR and NOMA-based one-way relaying counterparts.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.1 s.139
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• pp.64-72
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• 2005

Digital manufacturing is a technology to simulate the real manufacturing process using the virtual model representing the physical schema and the behavior of the real manufacturing system including resources, processes and product information. Therefore, it can optimize the manufacturing system or prevent the bottleneck processes through the simulation before the manufacturing plan is executed. This study presents a method to apply the digital manufacturing technology for the steel cutting process in shipyard. The system modeling of cutting shop is carried out using the IDEF and UML which is a visual modeling language to document the artifacts of a complex system. Also, virtual NC simulators of the cutting machines are constructed to emulate the real operation of cutting machines and NC codes. The simulators are able to verify the cutting shape and estimate the precise cycle time of the planned NC codes. The validity of the virtual model is checked by comparing the real cutting time and shape with the simulated results. It is expected that the virtual NC simulators can be used for accurate estimation of the cutting time and shape in advance of real cutting work.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4835-4855
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• 2018

In this paper, we study the sparse signal recovery that uses information of both support and amplitude of the sparse signal. A convergent iterative algorithm for sparse signal recovery is developed using Majorization-Minimization-based Non-convex Optimization (MM-NcO). Furthermore, it is shown that, typically, the sparse signals that are recovered using the proposed iterative algorithm are not globally optimal and the performance of the iterative algorithm depends on the initial point. Therefore, a modified MM-NcO-based iterative algorithm is developed that uses prior information of both support and amplitude of the sparse signal to enhance recovery performance. Finally, the modified MM-NcO-based iterative algorithm is used to estimate the time-varying sparse wireless channels with temporal correlation. The numerical results show that the new algorithm performs better than related algorithms.