• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1254-1258
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• 2004

This paper presents of position control of Permanent Magnet Synchronous Motor (PMSM) the implementation with Field Programmable Gate Array (FPGA) is proposed. Cascade control with inner loop as a current control and an outer loop as a position control is chosen for simplicity and fast response. FPGA is a single chip (single processing unit), which will perform the following tasks: receive and convert control signal, create a reference current signal, control current and create switch signal and act as position controller in a addition of zero form. The 10 kHz sampling frequency and 25 bit of floating point data are defined in this implementation.The experimental results show that the performance of FPGA based position control is comparable with the hardware based position control, with the advantage of control algorithm flexibility

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.171-176
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• 2020

This paper presents an implementation of a gesture recognition platform that can be used in a factory workplaces. The platform consists of signages that display worker's job orders and a control center that is used to manage work orders for factory workers. Each worker does not need to bring work order documents and can browse the assigned work orders on the signage at his/her workplace. The contents of signage can be controlled by worker's hand and arm gestures. Gestures are extracted from body movement tracked by 3D depth camera and converted to the commandsthat control displayed content of the signage. Using the control center, the factory manager can assign tasks to each worker, upload work order documents to the system, and see each worker's progress. The implementation has been applied experimentally to a machining factory workplace. This flatform provides convenience for factory workers when they are working at workplaces, improves security of techincal documents, but can also be used to build smart factories.

• International Commerce and Information Review
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• v.7 no.4
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• pp.305-322
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• 2005

To meet the demand of Korea's e-trade, global e-trade should be implemented and the global network is absolutely needed for the completion of e-trade. In this regard, this study suggested the concept and effect of global e-trade and analyzed the current status of PAA, ASEM projects which have been processing as pilot projects. Also, it derived tasks for the implementation of global e-trade through SWOT analysis and made up questions to the firms which are participating the pilot projects. Therefore, the four implementation models of global e-trade network are brought up. These models are very similar to each pilot project such as PAA, ASEM, and could be classified by developed and developing countries.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.12
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• pp.1034-1039
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• 2016

This paper presents the implementation and control of a small-scaled excavator system. The commercial miniature of an excavator system has been modified and its control hardware is embedded to access the feedback control. Encoder sensors are attached to the joint and a force sensor is mounted on the end-effector so that feedback position control is accessible as well as force control. The dynamic model of the excavator system is derived as a four linkage robot arm and its control performances are simulated. Experimental studies of contact force control tasks are conducted to test the control algorithm for the excavator system.

• Journal of Mechanical Science and Technology
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• v.16 no.12
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• pp.1633-1642
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• 2002

Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. The maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because hydraulic manipulators have the advantage of electric insulation. Meanwhile it is relatively difficult to realize autonomous assembly tasks particularly in the case of manipulating flexible objects such as electric lines. In this report, a discrete event control system is introduced for automatic assembly task of electric lines into sleeves as one of the typical task of active electric power lines. In the implementation of a discrete event control system, LVQNN (linear vector quantization neural network) is applied to the insertion task of electric lines to sleeves. In order to apply these proposed control system to the unknown environment, virtual learning data for LVQNN is generated by fuzzy inference. By the experimental results of two types of electric lines and sleeves, these proposed discrete event control and neural network learning algorithm are confirmed very effective to the insertion tasks of electric lines to sleeves as a typical task of active electric power maintenance tasks.

• Journal of the Korean Society of Systems Engineering
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• v.9 no.1
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• pp.65-84
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• 2013

This paper introduces a systems engineering approach to reliability centered maintenance to address some of the weaknesses. Reliability centered maintenance is a systematic, disciplined process that produces an efficient equipment management strategy to reduce the probability of failure [1]. The study identifies the need for RCM, requirements analysis, design for RCM implementation. Value modeling is used to evaluate the value measures of RCM. The system boundary for the study has been selected as containment spray pump and its motor drive. Failure Mode and Criticality Effects analysis is applied to evaluate the failure modes while the logic tree diagram used to determine the optimum maintenance strategy. It is concluded that condition based maintenance tasks should be enhanced to reduce component degradation and thus improve reliability and availability of the component. It is recommended to apply time directed tasks to age related failures and failure finding tasks to hidden failures.

• Journal of IKEEE
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• v.5 no.2 s.9
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• pp.164-173
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• 2001

In this paper, we have designed and implemented a new hard embedded real-time system to satisfy hard real-time constraints in moving independently. Real-time kernel should be small size, fast and predictable. Because of the great variety of demands on real time scheduling, a real time kernel should also include a flexible and re-programmable task scheduling discipline. In this paper, we present that real-time applications should be split into small and simple parts with hard real-time constraints. To satisfy these properties, we designed real-time kernel and general kernel, that have their different properties. In real-time tasks, interrupt processing should be run. In general kernel, non real time tasks or general tasks are run. The efficiency of the proposed hard embedded real-time system is shown by comparison results for performance of the proposal real time kernel with both RT-Linux and QNX.

• Journal of Educational Research in Mathematics
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• v.9 no.1
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• pp.333-350
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• 1999

The purpose of this study is to define performance assessment of mathematics, to make a model of performance task of mathematics for the first grade middle school students in higher group, to examine validity and reliability of performance task and to investigate the effects on the students' achievement and attitude. It first defines performance assessment and exanmines its main features and scoring methods. Based on these, nine performance assessment tasks and scoring criteria were designed for the first grade middle school students in higher group. The validity of performance tasks were examined by experts. The loaming achievement and mathematical attitude test between two groups were performed as pre and post test. The thinking of students about performance assessment was investigated by attitude survey. The results of this study are as follows: First, the validity of the performance tasks is very high. Second, The control group. Forth, there is a difference in student's attitude about mathematics between scorer reliability was high due to the scorer training. Third, there is little difference in teaming achievement between experimental and experimental and control group in 5% meaningful levels. That is, student's of both groups attitude about mathematics comes negatives, but the width of change of negative attitude in experimental group is less than control group. In the trend of negative attitude of mathematics as grade comes higher, this results showed that performance assessment of mathematics had positive influence on attitude of mathematics. The result of survey about mathematical performance assessment experience showed that students have positive attitude to performance assessment and recognized effectiveness of the performance assessment of mathematics.

• Journal of the Korea Society of Computer and Information
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• v.7 no.2
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• pp.1-8
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• 2002

By now, Schedulers for RMS and EDF are implemented for real-time Linux Scheduler. These Schedulers are used for do not consider there's characteristics. Missing Schedulability-test cause result that increase deadline miss rate. Also The present real-time Linux causes system halt Because of scheduling for unschedulable tasks . These appearances are very fatal for real-time system. Therefor, In this paper The peaceful schedulability-test use scheduler which is proper characteristics of RMS and EDF scheduling methods. This scheduler keeps deadline and eliminates system halt from scheduling unschedulable tasks. In this paper, we propose the schedulability-test algorithm and scheduler select algorithm for the effective management of tasks sets.

• The KIPS Transactions:PartD
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• v.15D no.2
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• pp.213-222
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• 2008

The existing approaches for the music application have not considered a real-time multi-tasking model. So, it suffers from a high complexity and a low flexibility in design as well as lack of predictability for the timely execution of critical tasks. In this paper, we design a new concurrent tasking architecture for a real-time embedded music system and examine if all real-time tasks can finish execution within their respective time constraints. The design is implemented on the Linux based Xhyper272 Board that uses the Intel Bulverde microprocessor.