• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.277-279
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• 2008

In this paper, a novel active boost converter for SR drive is proposed. An active capacitor circuit is added in the front-end. Based on this active capacitor network, when boost switch turns off, this network seems as passive capacitor network. And the voltage of boost capacitor can keep balance with dc-link voltage automatically. In the capacitor network, discharging voltage is general dc-link voltage in parallel-connected capacitors; charging voltage is double dc-link voltage in series-connected capacitors. When boost switch turns on, two capacitors are connected in series, and discharging voltage is up to double dc-link voltage. So the fast excitation current can be obtained from this mode. Profit from fast excitation and fast demagnetization mode, the performance and output power can be improved. Some computer simulations are done to verify the performance of proposed converter.

• International journal of advanced smart convergence
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• v.2 no.2
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• pp.10-15
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• 2013

An expert network administrator is not always stationed as disasters happen. In that case, it is desirable that a novice administrator is capable of taking part in network recovery operations as well. In this paper, an agent-based network management system in emergency situations is presented. We use the Active Information Resource based Network Management System (AIR-NMS) to relieve the human administrator from parts of her management tasks and present an interface that remotely can control this management system. The effectiveness of the system is demonstrated by experiments using a prototype system.

• International journal of advanced smart convergence
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• v.3 no.1
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• pp.1-6
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• 2014

An expert network administrator is not always stationed as disasters happen. In that case, it is desirable that a novice administrator is capable of taking part in network recovery operations as well. In this paper, aknowledge-based network management system in emergency situations is presented. We use the Active Information Resource based Network Management System (AIR-NMS) to relieve the human administrator from parts of her management tasks and present an interface that remotely can control this management system. The effectiveness of the system is demonstrated by experiments using a prototype system.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.111-111
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• 2000

The research of network system, being used to reduce automotive wiring harness, is reaching to the development of by-wire system. It is by-wire system that apply IVN(In-Vehicle-Network) to steering, braking system, and it has the advantage of mass-decreasing, easy to diagnose fault and so on. But until now, many developed device can't satisfied with reliability that system have ever had. So redundancy of each network module, i.e., It is only way to make backup module. This paper researches development of network module and redundancy management of backup module when error occurred for implementation of brake-by-wire system.

• Journal of Communications and Networks
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• v.11 no.4
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• pp.406-415
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• 2009

In this work, we consider performance modeling of a wireless sensor network with a time division multiple access (TDMA) media access protocol with slot reuse. It is assumed that all the nodes are peers of each other and they have two modes of operation, active and sleep modes. We model the sensor network as a Jackson network with unreliable nodes with on and off states. Active and sleep modes of sensor nodes are modeled with on and off states of unreliable nodes. We determine the joint distribution of the sensor node queue lengths in the network. From this result, we derive the probability distribution of the number of active nodes and blocking probability of node activation. Then, we present the mean packet delay, average sleep period of a node and the network throughput. We present numerical results as well as simulation results to verify the analysis. Finally, we discuss how the derived results may be used in the design of sensor networks.

• Journal of the Korea Society of Computer and Information
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• v.10 no.6 s.38
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• pp.253-260
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• 2005

Active networks not only allows the network nodes, switches or routers. to perform routing and forwarding but so allows their users inject customized programs into the nodes of the network or the packets. that may modify, store or redirect the user data flowing through the network. In this paper, we proposed a new network management system built using active network technology, that can solve problems inherent in most of existing legacy centralized network management systems. The main contribution is to present the Smart Router model that can reduce traffics due to managing networks by way of making control packets into simplified patterns. The disadvantages of the centralized network management are presented and the current solution for distributed network management are discussed. The performance improvements that our architecture offers are showed through a service example experiment.

• Smart Structures and Systems
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• v.6 no.5_6
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• pp.731-748
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• 2010

Impact detection and health monitoring are very important tasks for civil infrastructures, such as bridges. Piezoceramic based transducers are widely researched for these tasks due to the piezoceramic material's inherent advantages of dual sensing and actuation ability, which enables the active sensing method for structural health monitoring with a network of piezoceramic transducers. Wireless sensor networks, which are easy for deployment, have great potential in health monitoring systems for large civil infrastructures to identify early-age damages. However, most commercial wireless sensor networks are general purpose and may not be optimized for a network of piezoceramic based transducers. Wireless networks of piezoceramic transducers for active sensing have special requirements, such as relatively high sampling rate (at a few-thousand Hz), incorporation of an amplifier for the piezoceramic element for actuation, and low energy consumption for actuation. In this paper, a wireless network is specially designed for piezoceramic transducers to implement impact detection and active sensing for structural health monitoring. A power efficient embedded system is designed to form the wireless sensor network that is capable of high sampling rate. A 32 bit RISC wireless microcontroller is chosen as the main processor. Detailed design of the hardware system and software system of the wireless sensor network is presented in this paper. To verify the functionality of the wireless sensor network, it is deployed on a two-story concrete frame with embedded piezoceramic transducers, and the active sensing property of piezoceramic material is used to detect the damage in the structure. Experimental results show that the wireless sensor network can effectively implement active sensing and impact detection with high sampling rate while maintaining low power consumption by performing offline data processing and minimizing wireless communication.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.462-464
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• 2004

ActiveX is the general name for a set of Microsoft Technologies that allows users to re-use code and link individual programs together to suit their computing needs. In addition ActiveX technology Provides a standard model for interapplication communication that different programming language. ActiveX is based on COM(Component Object Model), the COM standard allow developer to create code and application from a multitude of different languages and build a defined interface to that code, making it easily accessible by other application. By using ActiveX, user can access the functionality of other applications running remote computer distributed through the network and communicate over the network to build distributed applications. LabVIEW provides access to other Windows applications using ActiveX technologies. So in this paper we implement distributed application using ActiveX technology for remote control and monitoring.

• Journal of the Korea Society for Simulation
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• v.12 no.3
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• pp.55-68
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• 2003

As mobile IP has been suggested only to support mobility of mobile station(MS) by which it dose nothing but guarantee MS's new connection to the network, it is for nothing in Quality of Service(QoS) after handoff of MS. QoS is very important factor in mobile IP network to provide multimedia applications and real-time services in mobile environment, and it is closely related to handoff delay Therefore as a main issue in mobile IP research area, handoff delay problem is actively studied to guarantee and promote QoS. In this paper, in order to resolve such a problem, we suggest Simple Network Management Network(SNMP) information-based routing that adds keyword management method to information-based routing in active network, and then propose QoS controlled handoff by SNMP information-based routing. After setting up routing convergence time, modeling of suggested method and existing handoff method is followed in order to evaluate the simulations that are carried out with NS-2. The result of simulation show the improvement of handoff delay, and consequently it turns off the QoS has been improved considerably.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.4
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• pp.17-22
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• 2009

FlexRay is a new standard of network communication system which provides solutions to the degradation problems generated by many ECU (Electronic Control Unit) connections in automobiles and automation systems. The upper bound of the data rate is 10Mbps and it provides two channels for redundancy In this paper, FlexRay system is first designed using SDL. For hardware implementation, FlexRay system is designed using Verilog HDL based on the SDL design result. The designed system is synthesized using Synopsys Design Compiler with the Magna/Hynix 0.18 um cell library. In this paper, to construct a FlexRay network, active star is used since active star systems can provide high speed data transmission up to 10Mbps. The performance of the star network is tested using one transmitter node and two receiver nodes.