• Proceedings of the KOSOMBE Conference
• /
• v.1996 no.05
• /
• pp.10-13
• /
• 1996

We have developed the digital polysomnograph system to enhance the manual sleep study. This system is composed of host PC and target board. The host computer is IBM-PC Pentium 133 MHz and the target board is PC31 (processor type: TMS320C31). These two Processors communicate with each other by dualport RAM. Target board acquire 16 channel sleep signals from the Polysomnographic system (GRASS model 78, USA) and digitize them. We used high resolution monitor$(1600{\times}1280)$ to simulate the paper-recording quality of polysomnographic signal. We also implemented the GUI based polysomnographic staging program on the windows environment. Clinicians can score the sleep stage, and edit and mark the event efficiently. Finally it can support making patient database.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.12
• /
• pp.91-102
• /
• 2005

Recently, concurrent error detection for the processor becomes important. But it imposes too much overhead to adopt concurrent error detection capability on the system. In this paper, a new approach to resolve the problems of concurrent error detection is proposed. A loop detection scheme is introduced to reduce the repetitive loop iteration and memory access. To reduce the memory overheat an offset to calculate the target address of branching node is proposed. Performance evaluation shows that the new architecture has lower memory overhead and frequency of memory access than previous works. In addition, the new architecture provides the same error coverage and requires nearly constant memory size regardless of the size of the application program. Consequently, the proposed architecture can be used as an cost effective method to detect control flow errors in the commercial on the shelf products.

• Journal of Energy Engineering
• /
• v.5 no.2
• /
• pp.153-159
• /
• 1996

The Sequence Of Event (SOE) system used in nuclear power plants is a part of the Plant Data Acquisition System (PDAS). The SOE system of the existing nuclear power plant shares the computer H/W and S/W with PDAS, and requires more complicated structure using three processors to provide the events or trip signals. Moreover, there are high potential of collision between synchronization signals and data transmitted to the Plant Computer System (PCS) when the synchronization signals are sent from PCS to the three SOE processors. When this collision happens the SOE system will break down, thus it is not possible to analyze the trend of events or trips. This paper issues the limitations item of the existing SOE system and proposes the novel SOE system using single processor. And the test system for proposed SOE system is designed, implemented and tested.

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.593-596
• /
• 2005

The MSC is a remote sensing instrument with very high performance that is to be installed on KOMPSAT2 satellite. The MSC consists of EOS (Electro-Optic Subsystem), PMU (Payload Management Unit) and PDTS (Payload Data Transmission Subsystem). PMU controls and monitors all the other payload units by sending commands and collecting telemetry. PMU is in charge of interfacing between payload system and satellite bus system. PMU gets commands from ground-station via OBC (On-Board Computer) that is a main controller of the satellite bus system and sends telemetry to the ground-station via OBC. There is a processor module, called SBC (Single Board Computer) in the PMU. The SBC is a main controller of the MSC system. The main roles of the SBC are payload mission management, command validation and execution, telemetry collection and monitoring, ancillary data handling, event reporting, power control of payload sub-units and communication with these units. Intel's 80486DX2 processor has been used for the SBC. Due to the fact that the SBC plays important roles for imaging mission execution and handles a lot of control data that is required for payload operation, it is required to make analysis of the CPU load when it is in maximum operation mode. In this paper, the analysis and measurement results of the SBC throughput in the maximum operation mode.

• Journal of Environmental Impact Assessment
• /
• v.20 no.3
• /
• pp.337-348
• /
• 2011

Urban environmental problem became one of major issues during its urbanization processes. Environmental impacts are assessed during recent urban planning and development. Though the environmental impact assessment considers meteorological impact as a minor component, changes in wind environment during development can largely affect the distribution pattern of air temperature, humidity, and pollutants. Impact assessment of local wind is, therefore, a major element for impact assessment prior to any other meteorological impact assessment. Computational Fluid Dynamics (CFD) models are utilized in various fields such as in wind field assessment during a construction of a new building and in post analysis of a fire event over a mountain. CFD models require specially formatted input data and produce specific output files, which can be analyzed using special programs. CFD's huge requirement in computing power is another hurdle in practical use. In this study, a CFD model and related software processors were automated and integrated as a microscale wind environmental impact assessment system. A supercomputer system was used to reduce the running hours of the model. Input data processor ingests development plans in CAD or GIS formatted files and produces input data files for the CFD model. Output data processor produces various analytical graphs upon user requests. The system was used in assessing the impacts of a new building near an observatory on wind fields and showed the changes by the construction visually and quantitatively. The microscale wind assessment system will evolve, of course, incorporating new improvement of the models and processors. Nevertheless the framework suggested here can be utilized as a basic system for the assessment.

• The Journal of the Korea Contents Association
• /
• v.3 no.4
• /
• pp.38-47
• /
• 2003

Distributed problem solving is the cooperative solution of problem by a decentralized and loosely couped collection of knowledge-sources (KS's), located in a number of distinct processor nodes. The contract net protocol has been developed to specify problem-solving communication and control for nodes in a distributed problem solver. Task distribution is affected by a negotiation process, a discussion carried on between nodes with tasks to be executed and nodes that may be able to execute tasks In this paper, we present the coordination method among distributed intrusion detection system and firewall by the contract net protocol. The method enhances the intrusion detection performance and provides the communication methods. To mode IDS and firewall, security models hue been hierarchically constructed based on the DEVS (Discrete Event system Specification) formalism. Each ID agent cooperates through the contract net protocol for detecting intrusions. The IDS which detects the intrusion informs to firewall, so the harmful network traffic is blocked. If an agent detects infusions, the agent transfers attacker's information to a firewall. Using this mechanism attacker's packets detected by In can be prevented from damaging the network.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.2
• /
• pp.579-603
• /
• 2018

In this paper we propose a QoS-enhanced intelligent stochastic optimal fair real-time packet scheduler, QUEST, for 4G LTE traffic in routers. The objective of this research is to maximize the system QoS subject to the constraint that the processor utilization is kept nearly at 100 percent. The QUEST has following unique advantages. First, it solves the challenging problem of starvation for low priority process - buffered streaming video and TCP based; second, it solves the major bottleneck of the scheduler Earliest Deadline First's failure at heavy loads. Finally, QUEST offers the benefit of arbitrarily pre-programming the process utilization ratio.Three classes of multimedia 4G LTE QCI traffic, conversational voice, live streaming video, buffered streaming video and TCP based applications have been considered. We analyse two most important QoS metrics, packet loss rate (PLR) and mean waiting time. All claims are supported by discrete event and Monte Carlo simulations. The simulation results show that the QUEST scheduler outperforms current state-of-the-art benchmark schedulers. The proposed scheduler offers 37 percent improvement in PLR and 23 percent improvement in mean waiting time over the best competing current scheduler Accuracy-aware EDF.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.17 no.4
• /
• pp.389-403
• /
• 2019

Large amounts of concrete waste are likely to arise from the decommissioning of a Kori-1 nuclear power plant. Several studies have been conducted on decommissioning concrete waste in recent decades, however, they have been limited to contaminated concrete issues or were small pilot-scale experiments. This study constructed two industrial-scale models of on-site concrete waste management for clean as well as contaminated concrete. To evaluate the performance of both the models, simulations were conducted using the Flexsim software. The concrete particle size distribution of Kori-1 and concrete processor properties based on widely used construction equipment were used as sources of input data for the simulations. It was observed that it may take over two years to complete the on-site concrete management processes owing to the performance of existing processors. In addition, it was demonstrated that it is essential to identify bottlenecks in the system and enhance the performance of the relevant processors to avoid delays of the decommissioning schedule. Our results suggest that this novel approach can contribute to developing schedules or expediting delayed activities in the Kori-1 decommissioning project.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.27 no.10
• /
• pp.78-88
• /
• 1990

To evaluate the performance of a multiprocessor system, a discrete event model of memory interference in the system employing multiple-bus interconnection networks is proposed. An analytic model of the system is presented and then simulator models are implemented for cross-verifying the analytic results and simulation results. The simulator model takes as input the number of processors, the number of memory modules, the number of buses and the local memory miss ratio. The model produces as output the memory bandwidth, the processor, memory module and bus utilization and the bus contention ratio. Using the model in the design of the system, it is possible to evaluate the system performance by analyzing the interaction of the input parameters.

• Journal of Digital Convergence
• /
• v.10 no.7
• /
• pp.185-192
• /
• 2012

The ultimate purpose of cities is 'the enhancement of quality of life in city'. In order to achieve this, it is required to optimize the Ontology-driven ubiquitous services included in the U-City and UIS of regions and communities and so on. Almost U-Service's contents are related to spatial or temporal extent. So it is important to design Spatio-temporal event schema for efficient access to U-City. There is a rapid change into an urban society in the shape of Ontology-driven ubiquitous services in which a content on a region or an incident is newly reconstructed through various ideas with the influence of the ubiquitous environment.