• The KIPS Transactions:PartC
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• v.10C no.4
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• pp.485-492
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• 2003

This paper presents a new modified input buffered switch, which called a grouped input buffered (GIB) switch, to eliminate the influence of HOL blocking when using multiple input buffers in ATM switches. The GIB switch consists of grouped sub switches per a network stage. The switch gives extra paths and buffered switching elements between groups for transferring the blocked cells. As the result, the proposed model can reduce the effect by the HOL blocking and thereafter it enhances the performance of the switch. The simulation results show that the proposed scheme has good performance in comparison with previous works by using the parameters such as throughput, cell loss, delay and system power.

• Journal of KIISE:Information Networking
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• v.29 no.4
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• pp.405-411
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• 2002

Open interfaces in the optica] Internet have been progressed by OIF's ISI, ITU-T ASTN's CCI and IETF's GSMP extensions with optical switching. These open interfaces enable the separation between the control plane and the optical transport plane. This separation allows flexibility in the network, but it suffers more setup delay than the traditional switch-by-switch connection setup. We propose the parallel interworking model, which will reduce the connection setup delay in the open interface of optical Internet. Based on the switch controller's caching capability about networks states, the parallel interworking procedures between signaling protocol and GSMP protocol are performed in the switch controller. We simulated and evaluated our proposed parallel interworking model and the existing sequential interworking model in terms of a connection setup delay and a completion ratio. We observed that the completion ratios of the two interworking models were quite close. However the connection setup delay of parallel interworking model is improved by about 30% compared with that of the sequential interworking model.

• Management Science and Financial Engineering
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• v.10 no.2
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• pp.89-102
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• 2004

In this paper, we deal with a processor assignment problem that minimizes the total traffic load of an ATM switch controller by optimally assigning processors to ATM interface units. We develop an integer programming (IP) model for the problem, and devise an effective tabu search heuristic. Computational results reveal the efficacy of the proposed tabu search procedure, finding a good quality solution within 5% of optimality gap.

• ETRI Journal
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• v.31 no.3
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• pp.298-303
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• 2009

A single-switch parallel resonant converter for induction heating is implemented. The circuit consists of an input LC-filter, a bridge rectifier, and a controlled power switch. The switch operates in soft commutation mode and serves as a high frequency generator. The output power is controlled via the switching frequency. A steady state analysis of the converter operation is presented. A closed-loop circuit model is also presented, and the experimental results are compared with the simulation results.

• Journal of KIISE:Information Networking
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• v.34 no.3
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• pp.203-217
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• 2007

In this paper, a performance evaluation model of Networks with the multiple-buffered crossbar switches is proposed and examined. Buffered switch technique is well known to solve the data collision problem of the switch networks. The characteristic of a network with crossbar switches is determined by both the connection pattern of the switches and the limitation of data flow in a each switch. In this thesis, the evaluation models of three different networks : Multistage interconnection network, Fat-tree network, and other ordinary communication network are developed. The proposed evaluation model is developed by investigating the transfer patterns of data packets in a switch with output-buffers. Two important parameters of the network performance, throughput and delay, are evaluated. The proposed model takes simple and primitive switch networks, i.e., no flow control and drop packet, to demonstrate analysis procedures clearly. It, however, can not only be applied to any other complicate modern switch networks that have intelligent flow control but also estimate the performance of any size networks with multiple-buffered switches. To validate the proposed analysis model, the simulation is carried out on the various sizes of networks that uses the multiple buffered crossbar switches. It is shown that both the analysis and the simulation results match closely. It is also observed that the increasing rate of Normalized Throughput is reduced and the Network Delay is getting bigger as the buffer size increased.

• Journal of KIISE:Information Networking
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• v.34 no.3
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• pp.193-202
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• 2007

In this paper, a performance evaluation model of the Multistage Interconnection Network(MIN) with the multiple-buffered crossbar switches under Hot-spot environment is proposed and examined. Buffered switch technique is well known to solve the data collision problem of the MIN. The proposed evaluation model is developed by investigating the transfer patterns of data packets in a switch. The performance of the multiple-buffered $a{\times}a$ crossbar switch is analyzed. Steady state probability concept is used to simplify the analyzing processes. Two important parameters of the network performance, throughput and delay, are then evaluated. To validate the proposed analysis model, the simulation is carried out on a Baseline network that uses the multiple buffered crossbar switches. Less than 2% differences between analysis and simulation results are observed. It is also shown that the network performance is significantly improved when the small number of buffer spaces is given. However, the throughput elevation is getting reduced and network delay becomes increasing as more buffer spaces are added in a switch.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.176-203
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• 2015

While the importance of adopting cloud computing service has been emerged, comparatively little research has been conducted on examining factors of an individual user's intention to switch toward cloud computing service. Hereafter, this study presents and empirically tests users' intention to switch to cloud computing. Our model posits that the characteristics of cloud computing such as effectiveness, economics, accessability, switching cost, security concern, and satisfaction toward existing IT service to cloud service affect perceived value, which in turn, influences intention to switch. An experimental study using student subjects provided empirical validation for our proposed model. Survey data from 204 respondents was used to test the model using partial least square analysis. As the result of the analysis, five hypotheses out of seven hypotheses were supported. According to our results, among the characteristics of cloud computing, effectiveness, economics, switching cost, and security concern were found to have significant impact on users' intention to switch that mediated by perceived value. Based on our research findings, we hope that this research will stimulate researchers' interest in the emerging area of cloud computing adoption.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.596-601
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• 2011

This paper has presented research results for the switching mode class E frequency multiplier that has simple circuit structure and high efficiency. Frequency multiplication is coming from the nonlinearity of the active component, and this paper models the FET active component as a simple switch and some parasitics to analyze the characteristics. The matching component parameters for the class E frequency doubler have been derived with modeling the FET as a input controlled switch and some parasitics. A circuit simulator, ADS, is used to simulate the output voltage and current waveform and efficiency with the variation of the parasitic values. With 2.9GHz input and 2V bias, the drain efficiency has been decreased from 98% to 28% with changing the parasitic capacitance from 0pF to 1pF at 5.8GHz output, which shows that the parasitic capacitance CP has the most significant effect on the efficiency among the parasitics of FET.

• ETRI Journal
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• v.25 no.1
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• pp.34-40
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• 2003

This paper considers a TMN-based management system for the management of public ATM switching networks using a four-level hierarchical structure consisting of one network management system, several element management systems, and several agent-ATM switch pairs. Using Jackson's queuing model, we analyze the effects of one TMN command on the performance of the component ATM switch in processing local calls. The TMN command considered is the permanent virtual call connection. We analyze four performance measures of ATM switches- utilization, mean queue length and mean waiting time for the processor directly interfacing with the subscriber lines and trunks, and the call setup delay of the ATM switch- and compare the results with those from Jackson's queuing model.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1199-1201
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• 2003

This paper presents an averaged switch model for an on-line deterioration analysis of inverters. The model is based on the operational characteristics of power diodes and IGBTS. Switching loss mechanisms are described and divided into the diode reverse-recovery mechanism, the IGBT current-tailing phenomenon, the IGBT turn-on time, and the output capacitances of the IGBTS and diodes. The deterioration analysis parameters are derived from the averaged switch modeling and the parameters can determinate the deterioration of the inverters.