• 산업공학
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• 제12권3호
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• pp.374-381
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• 1999

In this paper, we propose an architecture of the DNC system for Shop Floor Control/Point of Production(SFC/POP). The DNC system to be presented this paper retrieves line-up sheets which include the drawing information, making a index database for line-up sheets, NC programs and tool adjustment data. And it is interface with a raw material, jig and tool information. Also, the DNC system transmits operation information to real workers rapidly, and supports realtime monitoring by collecting the state information of machines directly. In the analysis and design phases, this paper models realtime events using the state transition diagrams. In the implementation phase, we use the ORACLE DBMS(Database Management System) as the DBMS and Developer 2000 and Microsoft Visual C++ 5.0 as the programming tools.

• 한국CDE학회논문집
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• 제5권4호
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• pp.312-318
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• 2000

In this study, an exclusive CAD/CAM system is developed for enhancing the effectiveness and productivity of CNC universal cylindrical grinding machines on which the external/facing/internal grinding cycles and the wheel dressing cycles are integratively carried out. The CAD/CAM system can manage the various processes such as geometry design, NC code generation, NC code verification, DNC operation, and so on. Especially, the feature-based modeling concept is introduced to improve the geometry design efficiency. And the NC code verification is realized by virtual manufacturing technique based on the real-time analysis of NC codes and the boolean operation between workpiece and wheel.

• 대한안전경영과학회지
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• 제5권2호
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• pp.87-98
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• 2003

With the development of CNC(Computer Numerical Control) and communication technology, the connotation and functions of Distributed Numerical Control have been greatly enlarged. In this study, we develop and implement a Distributed Numerical Control system that has real time and multi-tasking operation capability for the machining cell with various NC(Numerical Control) and CNC machines. With the consideration of economy, generalization and extension, this system is interfaced with Shop Floor Control System, Machine Control System and Tool Preparation System using advanced networking method. In the implementation phase, we use the ORACLE DBMS (Database Management System) as the DBMS and Microsoft Visual C++ as the programming tools.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권3호
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• pp.837-852
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• 2021

Recurrent neural network (RNN) architectures have been used for language modeling (LM) tasks that require learning long-range word or character sequences. However, the RNN architecture is still suffered from unstable gradients on long-range sequences. To address the issue of long-range sequences, an attention mechanism has been used, showing state-of-the-art (SOTA) performance in all LM tasks. A differentiable neural computer (DNC) is a deep learning architecture using an attention mechanism. The DNC architecture is a neural network augmented with a content-addressable external memory. However, in the write operation, some information unrelated to the input word remains in memory. Moreover, DNCs have been found to perform poorly with low numbers of weight parameters. Therefore, we propose a robust memory deallocation method using a limited retention vector. The limited retention vector determines whether the network increases or decreases its usage of information in external memory according to a threshold. We experimentally evaluate the robustness of a DNC implementing the proposed approach according to the size of the controller and external memory on the enwik8 LM task. When we decreased the number of weight parameters by 32.47%, the proposed DNC showed a low bits-per-character (BPC) degradation of 4.30%, demonstrating the effectiveness of our approach in language modeling tasks.

• 한국CDE학회논문집
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• 제1권2호
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• pp.150-157
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• 1996

The hob is considered as an effective gear cutting tool for achieving the various gears such as spur gear, helical gear, worm gear and so on. To enhance the productivity and precision of hobs and the competitive ability of domestic CNC hob relieving lathes, a CAM system for CNC hob relieving lathe needs to be realized. In this study, the CAM system is developed based on the personal computer and C language. Besides the automatic generation of CNC data, the developed CAM system has the various capabilities related to the generation of tool path, the cutting simulation for verifying the generated CNC data and forecasting the cutting time, the DNC operation for communicating the CNC data with CNC controller by RS232C port, and the estimation of undercut length for verifying the hob cutting conditions.

• 한국정밀공학회지
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• 제12권12호
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• pp.19-29
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• 1995

The basic technology for a production system represented by design, machining, assembly, and inspection, is machining technology such as CNC machine tools. etc. Direct Numerical Control, that effeciently manages NC programs is developing into Distributed Numerical Control that increases the utilization of the machining cell. It has the ability of monitoring and control, in real time, for CNC and periperial equipment. In this study, we develop a Distributed Numerical Control system that has real time and multitasking operation capability for the machining cell with various CNC's. With the consideration of economy, generalization and extension, the system is interfaced with CNC machine tools and periperial device using RS-485 network and RS-232C communication methods.

• 한국CDE학회논문집
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• 제4권4호
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• pp.339-349
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• 1999

The punose of this paper is to introduce the comprehensive CAM system (called PosCAM) supporting various function requested from shop floor operators. PosCAM is comported of two subsystems (PosCAM I and PosCAM II) which are designed to make up for the contemporary CAD/CAM systems. PosCAM I is mainly for : a) verifying the part programs written in both custom macros and standard G-codes, b) enhancing machining productivity and quality with built-in cutting conditions and feedrate optimization algorithm. PosCAM II is for : a) efficiently managing the numerous part programs and tool data stored in CNC memory, and b) integratively controlling and monitoring various CNCs from the control center through RS-422 with DNC 2 protocol. The developed systems have been tested via various experiments, and can be Applied for the industrial CNC machine shop as a means for enhancing productivity. The PosCAM system has been implemented and successfully used in the Machine Shop Department of PosCAM since march 1998.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.268-272
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• 1988

In this paper, we introduce the supermicro computer- based nonreal-time BTR type DNC system, which can provide valuable datas for production and management by monitoring the operation of NC equipments. (upto 48 NC machine) In accordance with manual job schedulinq, part program is combined with tool presetting datas and enables rapid downloading and uploading. An application to the production system of die & Mold plant is presented.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.290-295
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• 1989

This paper proposes a Expert CAPP System for integrating CAD/CAM of rotational work-part by rule based approach. The CAD/CAPP integration is performed by the recognition of machined features from the 2-D CAD data (IGES) file. Selecting functions of the process planning are performed in modularized rule base by forward chaining inference, and operation sequences are determined by means of heuristic search algorithm. For CAPP/CAM integration, post-processor generates NC code from route sheet file. This system coded in OPS5 and C language on PC/AT, and EMCO CNC lathe interfaced with PC through DNC and RS-232C.

• 한국전자파학회논문지
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• 제15권11호
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• pp.1069-1074
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• 2004

본 논문에서는 직렬 inter-digital 커패시터와 이중 병렬 인덕티브 쇼트 스텁으로 구성된 double negative(DNG) 전송 선로를 설계하였다. 이러한 DNG 전송 선로는 특정한 주파수 이상에서는 double positive(DPS) 전송 선로의 특성을 가진다. 다시 말해서, 설계된 전송 선로는 DNG와DPS전송 선로의 특성을 주파수에 따라서 동시에 가진다. 누설파 대역에서의 DPS/DNG 전송 선로는 주파수 스캐닝 안테나로 이용되어 질 수 있다. 대칭 누설파 안테나의 분산 특성과 원거리 방사 패턴을 모의실험하였고 제작 및 측정하였다. 모의실험 결과는 측정결과와 대략 일치하였다.