• Journal of Institute of Control, Robotics and Systems
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• v.5 no.1
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• pp.79-87
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• 1999

For its simplicity and cost effectiveness in implementation, the Inverted DGPS is well suited for some specific applications like automatic vehicle location systems, where the monitoring station needs accurate position of the vehicles in the street. In the Inverted DGPS, the user sends its GPS position and associated satellite informations to the reference station, and the corrections are made at the reference station to get differentially corrected user position. A fundamental requirement in IDGPS is that the user and the reference station must use the same satellites when the corrections are made. But in practice, it is not often satisfied. Inverted DGPS is also suffered from performance degradation as the baseline become large like DGPS. IDGPS system using multi-reference station can resolve this problem. In this paper a simple multi-reference IDGPS algorithm is proposed and some experiments and analysis are peformed. Experiment results show that IDGPS can achieve the positioning performance as accurate as the DGPS can provide.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.58-63
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• 2004

This study is to investigate a fracture characteristics of carbon fiber reinforced plastics (CFRP) under the tensile loading as a function of acoustic emission (AE) according to the frequency analysis (transient mode) and AE source location (location mode). It was found that the fracture mechanism of AE frequency analysis was a useful tool for the estimation of different type of fracture in CFRP, i.e., matrix(epoxy resin) cracking, delamitation and fiber breakage same as AE amplitude distribution.

• Smart Structures and Systems
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• v.6 no.2
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• pp.147-165
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• 2010

Impact damage detection in composite structures has gained a considerable interest in many engineering areas. The capability to detect damage at the early stages reduces any risk of catastrophic failure. This paper compares two advanced signal processing methods for impact location in composite aircraft structures. The first method is based on a modified triangulation procedure and Genetic Algorithms whereas the second technique applies Artificial Neural Networks. A series of impacts is performed experimentally on a composite aircraft wing-box structure instrumented with low-profile, bonded piezoceramic sensors. The strain data are used for learning in the Neural Network approach. The triangulation procedure utilises the same data to establish impact velocities for various angles of strain wave propagation. The study demonstrates that both approaches are capable of good impact location estimates in this complex structure.

• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.57-64
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• 2016

This paper deals with the PCB assembly time minimization problem that the PAP (pick-and-placement) machine pickup the K-weighted group of N-components, loading, and place into the PCB placement location. This problem considers the rotational turret velocity according to component weight group and moving velocity of distance in two component placement locations in PCB. This paper suggest heavy-weight component group first pick-and-place strategy that the feeder sequence fit to the placement location Hamiltonean cycle sequence. This algorithm applies the quadratic assignment problem (QAP) that considers feeder sequence and location sequence, and the linear assignment problem (LAP) that considers only feeder sequence. The proposed algorithm shorten the assembly time than iATMA for QAP, and same result as iATMA that shorten the assembly time than ATMA.

• Journal of Information Display
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• v.8 no.4
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• pp.15-18
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• 2007

In this paper, we investigated the SLS process to control grain boundary(GB) location in TFT channel region, and it has been found to be applicable for locating the GB at the same location in the channel region of each TFT. We fabricated TFT by applying a new alignment SLS process and compared the TFT characteristics with a normal SLS method and the grain boundary location controlled SLS method. Also, we have analysed degradation phenomena under hot carrier stress conditions for n-type LDD MOSFETs.

• Journal of Information Science Theory and Practice
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• v.2 no.2
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• pp.33-47
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• 2014

Mobile devices are the most important equipment for accessing various kinds of services. These services are accessed using wireless signals, the same used for mobile calls. Today mobile services provide a fast and excellent way to access all kinds of information via mobile phones. Mobile service providers are interested to know the access behavior pattern of the users from different locations at different timings. In this paper, we have introduced an associated tree for analyzing user behavior patterns while moving from one location to another. We have used four different parameters, namely user, location, dwell time, and services. These parameters provide stronger frequent accessing patterns by matching joins. These generated patterns are valuable for improving web services, recommending new services, and predicting useful services for individuals or groups of users. In addition, an experimental evaluation has been conducted on simulated data. Finally, performance of the proposed approach has been measured in terms of efficiency and scalability. The proposed approach produces excellent results.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.3
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• pp.47-58
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• 1989

^x Residential satisfaction by apartment housing type and by location was examined in Seoul Korea for a sample of 303 housewives disaggregated into four housing subgroups. These group differ in their personal characteristic by housing type and location. They showed significant differences in their levels of satisfaction and in their perception and evaluation of several community, neighborhood and housing unit attributes. A regression model of satisfaction for entire sample explain about 45% of the variation, but this conceals the compositional and the contextual differences between groups. Seperate regression for the four groups explain an average of 63% of the variation in residential satisfaction. Residents of high-rise and low-rise apartments both of center and periphery location differ significantly both from each other. Results show that certain dwelling, neighborhood and community context elicit dissatisfaction across the full sample. The objective contextual factor of housing type prove significant in most compositional subsamples, indicating that sources of residential satisfaction are not same in everywhere.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.16-19
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• 2007

In this paper, we present work that has been carried out using the SLS process to control grain boundary(GB) location in TFT channel region and it is possible to locate the GB at the same location in the channel region of each TFT. We fabricated TFT by applying a new alignment SLS process and compared the TFT characteristics with a normal SLS method and the grain boundary location controlled SLS method. Also, we have analyzed degradation phenomena under hot carrier stress conditions for n-type LDD MOSFETs.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.4
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• pp.144-150
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• 2006

IEC 61850 is the worldwide protocol for the substation automation system. IEC 61850 transports the information which consists of different formats such as GOOSE(Generic Object Oriented Substation Event), MMS(Manufacturing Message Specification), SV(Sampled Values) and so on. For real time data transmission, GOOSE can be used. The remote-bus current data which were collected in a local-bus current differential IED can be transmitted to a distance IED at the same location by using GOOSE messages. The distance IED can eliminate the reactance effect by using the transmitted remote-bus current data. This method can improve the performance of the fault location.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.71-72
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• 2014

This paper presents a method to find the fault location on the DC cables for the HVDC transmission systems which utilizes a hybrid topology of the diode rectifier and the voltage-source converter (VSC) in the wind farm (WF) side. First, the DC-cable fault occurring in this HVDC system is analyzed in detail. Then, the DC-cable fault location is detected from the two relative voltages located on the same section of the cable, which are estimated from a pair of DC-cable voltage and current measurements. The effectiveness of the method is verified by the simulation results.