• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.2
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• pp.119-126
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• 2015

The information about noise parameters is essential in the design of low noise amplifier. In the past, the noise parameters were measured using an impedance tuner and noise figure analyzer. Recently, the authors proposed the method of measuring the noise parameters using the 8-port network without the aid of the mechanically driven impedance tuner. However, the 8-port method still requires the noise source and causes the complexity in the measurements. In this paper, a novel measurement method of the noise parameters without the noise source using 6-port network is proposed. Based on the proposed 6-port method, the noise parameters of 10 dB attenuator whose noise parameters can be theoretically determined were measured and the measured noise parameters are compared with those measured using the previous 8-port network method. As a result, the accuracy of the measured noise parameters using 6-port network is found to be comparable to the previous 8-port network method.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.3
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• pp.99-106
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• 2002

This study presents an approach to model the Electric Railway System with the common grounding based on the 8-port network model and to analyse traction power feeding system focused on the amplification of harmonic current. The entire system can be easily modeled by the combination of 8-port representation of each component in parallel and/or series. Through the research, 8-port network model which can be effectively applied to harmonic analysis is derived.

• Journal of Navigation and Port Research
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• v.31 no.8
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• pp.725-731
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• 2007

This paper aims to analyze an action about a port choice of shipper between two ports. For this propose, this paper analyzed a port choice action for Kwangyang and Busan port using a fuzzy logic and neural network. Also, this paper compared classification performance of fuzzy-neural network to Logit model, and analyzed a port choice action into change Para-meta such as freight volumes and service standard.

• Journal of Korea Port Economic Association
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• v.25 no.2
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• pp.177-200
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• 2009

This study extracted the major attributes of the competitiveness of services provided by port logistics networks from previous research and interviews with experts and, based on the attributes, analyzed the effects of change in the competitiveness of the Incheon Port. According to the results, services provided by port logistics networks were divided into facility conveniences, access conveniences, and decision conveniences. In the results on the integrated value of the competitiveness of logistics network among ports, competitiveness was high in order of Busan Port>Qigndao Port>Tianjin Port>Dalian Port>Incheon Port. Particularly in the results of scenario analysis, with the elevation of one or two factors of logistics network service, the Incheon Port was even inferior to the Dalian Port, which had the lowest competitiveness among the ports compared. In the results of reversed fuzzy analysis, the Incheon Port could maintain equal competitiveness with the Dalian Port by raising the service level of the logistics network by 25% for facility conveniences, by 8% for access conveniences, and by 1% for decision conveniences.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.8
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• pp.808-820
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• 2014

In this paper, we fabricated two on-wafer type DUT(Device-Under-Test)s; a 10-dB attenuator and an amplifier using commercially available MMIC and we proposed the measurement method of the noise parameters for the two fabricated DUTs. Since the 10-dB attenuator DUT is a passive device, its noise parameters can be accurately determined when its S-parameters are measured. In the case of the amplifier DUT, its noise parameters are available in the datasheet. Hence, the measured noise parameters using the proposed method can be assessed by comparing with the known noise parameters. The noise parameter measurement method having been presented by the authors requires the S-parameters of the 8-port network used in the measurement and limited to coaxial type DUTs. When on-wafer probes are included in the 8-port network, the 8-port S-parameters requires the measurements with different kinds of connectors. In this paper, we obtained the 8-port S-parameters using the Smart-Cal function in the network analyzer. The measured noise parameters shows about ${\pm}0.2dB$ fluctuations for $NF_{min}$. Other noise parameters with the frequency change show good agreement with the expected results.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.589-593
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• 2013

An efficient measurement methodology is proposed to construct the scattering parameters of a multi-port device using a four-port vector network analyzer (VNA) without the external un-terminated ports. By using the four-port VNA, the reflected waves from the un-terminated ports could be minimized. The proposed method significantly enhances the accuracy of the S-parameters with less number of measurements compared to the results of classical renormalization technique which uses two-port VNA. The proposed method is validated from the measured data with the coupled 8-port micro-strip lines.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.429-432
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• 2001

This study presents an approach to model and to analyse traction power feeding system focused on the amplification of harmonic current. Through the research, 8-port network model which can be effectively applied to harmonic analysis is derived.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.243-253
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• 2017

This study aims to compare Jeju Island, Shanghai, and Yokohama cruise ports and to investigate the relative strengths and weaknesses of Jeju Island. This study conducted comparative evaluation of 8 factors [airport, berth, expenses, distance, access to town, shopping facilities, source market (background market), and tourism] through a cruise network analysis. Comparative evaluation results find that Jeju Island, which secured 2 berths (berthing capacity) by completion of the civil-military complex port, has ascendancy over Shanghai cruise port and will have ascendancy over Yokohama cruise port once construction of the new airport is completed. Therefore, it will qualify as the best cruise port in Northeast Asia in the future. Results obtained from the cruise network analysis provide insights for administrative policy. Study limitations include only eight factors are used for evaluating the cruise-ship harbor area and surrounding hinterlands, and thus cannot sufficiently evaluate the complex conditions of the sites. In the future, it is necessary to reexamine the evaluation factors of the cruise ship harbor in detail. Furthermore, future research will need to consider the economic effects of the cruise ship industry, and its relevance to related industries as a possible fusion or hybrid industry.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.1
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• pp.131-143
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• 1996

In this paper, we propose the improved structure of fully interconnected ATM Switch to develop the small sized switch element and represent practical implementation of switch network. As the part II of the full study about structure and implementation of fully interconnected ATM Switch, this paper especially describes the implementation of an ATM switching element with 8 input port and 8 output port at 155 Mbits/sec each. The single board switching element is used as a basic switching block in a small sized ATm switch for ATM LAN Hub and customer access node. This switch has dedicated bus in 12 bit width(8 bit data + 4 bit control signal) at each input and output port, bit addressing and cell filtering scheme. In this paper, we propose a practical switch architecture with fully interconnected buses to implement a small-sized switch and to provide multicast function withoutany difficulty. The design of switching element has become feasible using advanced CMOS technology and Embedded Gate Array technology. And, we also represent Application Specific Integrated Circuit(ASIC) of Switch Output Multiplexing Unit(SOMU) and 12 layered Printed Circuit Board for interconnection network of switch.

• Journal of the Korea Society for Simulation
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• v.8 no.2
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• pp.101-109
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• 1999

In a commercial facsimile network system, a simulation analysis has been performed using ARENA due to the unavailability of theoretical models. The effect of a priority is compared with that of the current FCFS rule on the arriving call blocking rate and transmission time delay. The result shows that the priority rule reduces more service time delay as the arrival rate increases. A simulation analysis procedure is proposed to select optimal in/out port ratio at various hourly arrival rates with a given multiple-place transmission requests ratio.