• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1741-1747
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• 2010

The development of overload management systems for distribution transformers offers new opportunities for improving the reliability of distribution systems. It allows network planners to optimize the system resource utilization and investment cost. Such an improvement in the flexibility of the distribution network is only possible if the operator has more accurate knowledge of the realtime conditions of distribution transformers. In this paper, we present an improved overload decision system for distribution transformers using realtime monitoring data. Our study can be categorized into two parts: (a) improvement in the criteria for judging the overload conditions of distribution transformers and (b) development of an overload evaluation system using realtime monitoring data. In order to determine the overload criteria, overload experiments are performed on sample transformers; the results of these experiments are used to define the relationship between the transformer overload and the increase in the top-oil temperature. To verify the accuracy of the experimental results, field tests are performed using specially manufactured transformers, the loads and top-oil temperatures of which can be measured. For arriving at online overload decisions, we propose methods whereby the measured load curve can be converted into an overload characteristic curve and the overload time can be calculated for any load condition. The developed system is able to evaluate the overload for individual distribution transformers and calculate the losses using realtime monitoring data.

• Journal of the Korea Society of Computer and Information
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• v.14 no.1
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• pp.153-161
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• 2009

In this paper, we designed and implemented realtime DID(digital information display) system based on web server that displayed multimedia contents. The contents are weather, news information on the internet web sites and public relations or advertisements data on local systems. The DID system has client/server architecture that the server send to client that schedule informations and multimedia contents received form web server and the client displayed the contents though scheduled information. Therefore the systems overcome network fault for the mean time. Also, the system has realtime services of web page filtering function that extract the partial information of specific web pages.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.93-104
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• 2005

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.126.4-126
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• 2001

Recently, researches on CIM in product lines of industrial plant are widely progressed, automation of working environment with modernization of product equipments is realized and also, installation of integrated control system based on computer is activated. Since the CIM system is basically developed by using computer, there are several complicated problems such as design problem of hardware interface between computer and many product machines with individual special functions, software development problem with realtime data process and multi communication functions for realtime data monitoring and control of product machines This paper shows the development results for a single board type of microcontroller and a monitoring software based on realtime processing database system ...

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.117-120
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• 2002

A single DSP implementation of 3D sound movement is described. With the use of a realtime 3D acoustic image localization algorithm, an efficient approach is devised for synthesizing the 3D sound movement by interpolating only two parameters of "delay" and "gain". Based on this algorithm, the realtime 3D sound synthesis is performed by a commercially available 16-bit fixed-point DSP with computational labor of 65 MIPS and memory space of 9.6k words, which demonstrates that the algorithm call be used even for the mobile applications.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9A
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• pp.1314-1321
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• 1999

This paper presents a performance comparison of commercial realtime operating systems which is widely used and guarantees short response time for call processing in IMT-2000 base station. For this, we analyzed wireless call process and extracted primitives which have strong influence on the performance of the system are derived. Constructing and running a test-bed for call processing on the basis of the analysis, we tested if there's a bottleneck in the performance of the system and compared the performances among the commercial realtime operating systems.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.9
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• pp.878-886
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• 2012

This paper investigates the implementation and flight test of realtime vision guided autopilot system based on virtual instrumentation platform. A graphical design process via virtual instrumentation platform is fully used for the image processing, communication between systems, vehicle dynamics control, and vision coupled guidance algorithms. A significatnt ojective of the algorithm is to achieve an environment robust autopilot despite wind and an irregular image acquisition condition. For a robust vision guided path tracking and hovering performance, the flight path guidance logic is combined in a multi conditional basis with the position estimation algorithm coupled with the vehicle attitude dynamics. An onboard flight test equipped with the developed realtime vision guided autopilot system is done using the rotary UAV system with full attitude control capability. Outdoor flight test demonstrated that the designed vision guided autopilot system succeeded in UAV's hovering on top of ground target within about several meters under geenral windy environment.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.362-367
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• 2005

Control network adopted in the national power-plant or manufactory are mostly vendor-dependent products, which have their own special specification, components and individual communication methods. These systems not only raise installation cost, but also bring many difficulties to maintenance and extension. To overcome these problems, this paper introduces a development and application case of a new "PC/Ethernet-based fieldbus" architecture and protocol to be used in mid-level fieldbus. The designed system has a basic idea of "3 Layers fieldbus over Standard-LAN" and implemented on PCs. PC gives user friendly environment. By using an open standard Ethernet in layer 1,2, the system has low cost, wide communication bandwidth and high compatibility. Layer 3 protocol designed for large realtime data communication makes user bypass TCP/IP layer and gives user direct access to the Ethernet. This new protocol eliminates potential collision of Ethernet, and transmits large periodic/non-periodic control data by using long-frame/wide-bandwidth of Ethernet effectively, and offers simple API-Services to the upper layer. Since the system have installed in H-power plant simulator and U-nuclear power plant simulator in Korea, it have been proved to be efficient and stable without any trouble in realtime communication service for full-scope plant simulator that has a lot of control elements.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1691-1693
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• 2007

Establishing the realtime remote monitoring system of the moving test train is the important issue for the railway systems that provide comfort travel to the passengers. But it is not easy to transmit train's test data to remote site because the train runs tunnels. In this paper, we introduce the realtime monitoring system using wireless communication system which is installed in the test train. This system can provide both correct positions of unstable track and train's running status such as speed, kilopost and acceleration.

• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.167-174
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• 2009

We have recently studied the application of Information Technology to agricultural industry for competitive power. Because the big stockyards are far away from the house, we need a realtime monitering and control system to manage it efficiently. This paper presented design and implementation for a realtime monitering and controlling system that we can use to watch an movement of an electronic devices in the stockyards. Compared to other systems, we have more trust in our system by confirming an operation of devices through a realtime video streaming.