• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.111-119
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• 1997

The operating characteristics of the check valve in the clutch piston of an automatic transmission have a great effect on the shifting performance. This paper addresses the modeling, dynamic analysis, and optimization of the check valve. It was found that the vortex causes a pressure drop, which is related to the rotating speed of the clutch piston, oil volume discharged from the check valve, and valve geometry. Maximizing the oil volume discharged, geometry of the check valve is optimized. The results can be used to design an improved check valve which provides a suitable oil pressure curves for achieving smoother shifting.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.119-127
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• 2006

This paper deals with the middleware and S/W development of real time automatic attendance check management system using ubiquitous 900Mhz RFID(Radio Frequency Identification). This system supports the real time automatic attendance check and necessary data processing in class management. We expect to decrease the effort for class management and to upgrade the status of real time management of class.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.813-818
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• 2007

A method for automatic check of omitted design item in structural calculation document of steel box bridges is proposed. A method for automatic check of omitted design item in structural calculation document of steel box bridges is proposed. Information processing for the proposed method is divided into two steps: automatic generation of document structure in XML Schema Definition (XSD) format and extract omitted design items by using the XML Schema matching technique. The automatic omitted element filter is developed on the basis of the proposed method, and the accuracy of the developed module is examined with case study subjected to existing structural calculation document samples.

• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.102-109
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• 2002

This paper presents a method for automatic generating of check sheet to measure deep-drawn sheet metal. By using polyhedral model of CAD, the proposed procedure calculates measuring points automatically. The results of measure are exported to MS-Excel. The proposed method is implemented by API functions and C language using SPEED plus CAD/CAM system and MS-Window OLE.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.293-302
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• 1999

This paper presents an efficient reengineering technique for the logistics process innovation which is the foundation of supply-chain management. Based on consulting experience on the domestic manufacturing firms, this paper provides promotion step for logistics innovation and six reengineering points including check system for customer's credit limit, check system of real-time inventory information, automatic system for sequential production plan, automatic order-release system, automatic packing system, and happy-call system for order-forward information. For each reengineering point, application cases in domestic industry are also presented.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.9-19
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• 1997

In this paper, the modeling and analysis of dynamic characteristics has been carried out for friction clutches and brakes in an automatic transmission. From the operating oil pressure generated by the valve-body, time delay by check valve and the movement of piston has been examined. Also torque capacity and torque transferred at the clutch is studied. Heat capacity and temperature distribution at the reaction plate of clutch are codeled by time-dependent, nonhomogeneous partial differential equation, and brake torque, brake time, and the amount of heat generated are investigated. It is found that the time delay at the check valve is very short but dominant at the spool.

• Atmosphere
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• v.29 no.4
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• pp.501-509
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• 2019

Asian Dust is a meteorological phenomenon that sand particles are raised from the arid and semi-arid regions-Taklamakan Desert, Gobi Desert and Inner Mongolia in China-and transported by westerlies and deposited on the surface. Asian dust results in a negative effect on human health as well as environmental, social and economic aspects. For monitoring of Asian Dust, Korea Meteorological Administration operates 29 stations using a continuous ambient particulate monitor. Kim et al. (2016) developed an automatic quality check (AQC) algorithm for objective and systematic quality check of observed PM₁₀ concentration and evaluated AQC with results of a manual quality check (MQC). The results showed the AQC algorithm could detect abnormal observations efficiently but it also presented a large number of false alarms which result from valid error check. To complement the deficiency of AQC and to develop an AQC system which can be applied in real-time, AQC has been modulated. Based on the analysis of instrument status codes, valid error check process was revised and 6 status codes were further considered as normal. Also, time continuity check and spike check were modified so that posterior data was not referred at inspection time. Two-year observed PM₁₀ concentration data and corresponding MQC results were used to evaluate the modulated AQC compared to the original AQC algorithm. The results showed a false alarm ratio decreased from 0.44 to 0.09 and the accuracy and the probability of detection were conserved well in spite of the exclusion of posterior data at inspection time.

• Journal of the Korea Society of Computer and Information
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• v.15 no.6
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• pp.1-9
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• 2010

This paper proposes a test method for compliance of SMS encoder and decoder modules with 3GPP (3rd Generation Partnership Project) specification on SMS PDU (Protocol Data Unit). The existing tools have focused on providing an SMS gateway and on helping to view and edit a single SMS PDU, which rarely help to resolve the compliance test problem. The proposed compliance test method is based on an automatic generation of SMS PDUs fully compliant with the 3GPP specification by using QuickCheck library written in Haskell. By applying the proposed method to a C-based SMS encoder and decoder in Linux Mobile platform, we have found out several critical bugs such as wrong interpretation of time stamps in BCD format. The automatic SMS PDU generator is reusable in that it only depends on the 3GPP SMS specification. The QuickCheck library is also applicable for testing other network protocol data encoders and decoders, as used in this paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10B
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• pp.994-1003
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• 2009

For Automatic Meter Reading System, good topology of check machines, concentrators, and repeaters in client field is important. Steiner Minimum Tree is a minimum cost tree connecting all given nodes with introducing Steiner points. In this paper, an efficient mechanism allocating and connecting check machines, concentrators and repeaters which are essential elements in automatic meter reading system is proposed, which conducts repeated applications of building approximate Minimum Steiner Trees. In the mechanism, input nodes and Steiner points might correspond to check machine, concentrators or repeaters and edges might do to the connections between them. Therefore, through suitable conversions and processes of them, an efficient network for automatic meter reading system with both wired and wireless communication techniques could be constructed. In our experiment, for 1000 input nodes and 200 max connections per node, the proposed mechanism shortened the length of produced network by 19.1% comparing with the length of Minimum Spanning Tree built by Prim's algorithm.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.125-130
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• 2013

In this paper, in order to overcome shortcomings of manual inspection for the automotive PWM Shaft, we developed an automated inline inspection system. The automated inline inspection system consists of the work feeder unit, conveying unit, outer diameter check unit, run-out and roundness check unit, machine vision, defective separation unit and status alarm unit. We used the machine vision system for automatic inspection process and designed the inline systems for automatic feeding and selecting process. Also the repeated operation test was performed in order to verify the precision and reliability of the proposed automated inline inspection system.