• Journal of Advanced Marine Engineering and Technology
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• v.36 no.1
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• pp.141-148
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• 2012

The power system of leisure ship has a character of stand-alone type, so it continuously checks the usable power. Especially, the leisure ship using renewable energy needs to adjust the power consumption of loads according to the usable power. Also, the important loads of leisure ship are different by operation mode. However, current power management system doesnot consider such character. This paper studied load management system of the SPMS(Smart Power Management System) and composed using the smart plug. The SPMS controls the loads depending on a user's pattern and character through variable priority number control. This control algorithm was verified through simulation of assumed user and situation using LabVIEW.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.6
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• pp.331-338
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• 1988

A simple algorithm is presented for solving the thermal unit commitment problem which is one of very important areas in economic operation of power systems. This algorithm is based on simple priority ordering by the unit operation cost and it is shown that the operation cost of chosen sets of generators is the minimum. The proposed method differs from the conventional priority-based formulations in that the unit operation are calculated in every load level. Further the poerating reserve requiements are satisfied by the newly derived analytical security function or the expectation of reserve. The proposed method is proven to be very simple, accurate and efficient in a sample system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.44 no.3
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• pp.270-273
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• 1995

This paper proposes an optimal load shedding algorithm by which the system loss can be minimized when the load shedding is unavoidable in case of severe contingency such as the outage of key generators or lines. Shedding load .DELTA.S = .DELTA.P + J.DELTA.Q(MVA) is performed on the weakest bus (on the view of voltage stability), step by step, by the priority of the I.DELTA. = SQRT(.lambda.$\_$P/$\^$2/ + .lambda.$\_$Q/$\^$2/) index given for each load bus, where .lambda.$\_$P/ and .lambda.$\_$Q/ are the sensitivity indices representing the system loss variation versus active and reactive power change of the bus load bus. All loads are assumed to be constant power loads for convenience. A 5 bus sample system proves the effectiveness of the algorithm proposed.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.630-632
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• 2003

This paper describes allocation strategies of controllable loads for load aggregator in power market with the direct load control (DLC) program, which is carried out the two-way confirmation procedure. So, it is needed to the priority among the controllable loads to perform effectively and quickly the confirmation task. In this paper, allocation strategies for market operator and/or load aggregator are proposed, which are based on the basic load patterns defined in this paper. To verify the soundness of proposed strategies. case study on a sample system is performed.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.576-578
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• 2014

하나의 시스템을 다수의 사용자가 사용하는 경우 한정된 시스템의 자원을 효율적으로 배분하기 위하여 작업관리 시스템을 사용한다. 이러한 작업관리 시스템은 여러가지 종류가 있으며 시스템의 특성과 사용의 작업 패턴을 고려하여 적당한 작업관리 시스템을 선택하여 사용한다. IBM 시스템은 자체로 제공하는 작업관리 시스템인 LoadLeveler 주로 사용하고 있으며, 최근에는 몇가지 기능이 향상된 LSF를 이용하는 추세이기도 하다. 작업관리 시스템의 LoadLeveler에서는 CPU 수에 따라서 작업 우선 순위를 부여하고자 할 때 이러한 기능을 할 수 있는 환경 변수가 제공되지 않는데, 이러한 LoadLeveler의 환경에서 시스템의 환경파일에 스크립트 프로그램으로 이러한 기능을 구현하여 CPU 수에 따른 작업 우선순위를 적용함으로서 시스템 전체의 처리 효율을 향상 할 수 있게 하였다.

• Journal of Korean Society on Water Environment
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• v.39 no.5
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• pp.377-389
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• 2023

Chungcheongnam-do has been measuring the flow rate and water quality of streams in the province once a month since 2011 in order to water environment policies. Based on the results, after evaluating the coefficient of variation and the tendency of the water quality trend by using the Mann-Kendall test and Sen's Slope for each stream, the streams subject to priority introduction of Total Pollution Load Management at Tributaries were selected through the Stream Grouping Method. The water quality trend analysis results for 125 streams using the Mann-Kendall test and Sen's Slope were evaluated as streams showing a tendency of deteriorating water quality Biochemical oxygen demand (BOD): 13 streams, Total Phosphorus (T-P): 16 streams). Streams with deteriorating water quality were classified into A-D groups using the Stream Grouping Method. Group A, which has a high flow rate and high water quality, is a stream that requires priority management, and was selected as a stream for introduction of Total Pollution Load Management at Tributaries. There are 7 streams that need to be introduced into the BOD category, and there are 7 streams that need to be introduced into the T-P category. In this study, based on flow and water quality monitoring data accumulated over a long period of time (2011-2022), statistical techniques are used to select watersheds in which water quality is deteriorating. Accordingly, it is expected that it will be useful in establishing a water quality improvement plan in the future.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.444-446
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• 2003

This paper deals with an allocation strategy for the resources of direct load control program, which is considered the operating states in power systems. The existing approaches, load shedding priority algorithm, curtailment payback based algorithm and mixed curtailment algorithm, are based on the uniform allocation strategy. These approaches are not taken into account the operating states in power systems. So, under the critical operating condition, direct load control resource is evaluated by introducing the congestion factor.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.4
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• pp.1302-1320
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• 2015

In cloud, everything can be provided as a service wherein a large number of users submit their jobs and wait for their services. hus, scheduling plays major role for providing the resources efficiently to the submitted jobs. The brainwave of the proposed ork is to improve user satisfaction, to balance the load efficiently and to bolster the resource utilization. Hence, this paper roposes an Adaptive Multilevel Scheduling System (AMSS) which will process the jobs in a multileveled fashion. The first level ontains Preprocessing Jobs with Multi-Criteria (PJMC) which will preprocess the jobs to elevate the user satisfaction and to itigate the jobs violation. In the second level, a Deadline Based Dynamic Priority Scheduler (DBDPS) is proposed which will ynamically prioritize the jobs for evading starvation. At the third level, Contest Mapping Jobs with Virtual Machine (CMJVM) is roposed that will map the job to suitable Virtual Machine (VM). In the last level, VM Scheduler is introduced in the two-tier VM rchitecture that will efficiently schedule the jobs and increase the resource utilization. These contributions will mitigate job iolations, avoid starvation, increase throughput and maximize resource utilization. Experimental results show that the performance f AMSS is better than other algorithms.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.2
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• pp.34-39
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• 2010

This paper proposes S/W Watch-Dog method between Dual CPU using the different OS. The proposed watch-dog method performs that it distinguishes the status of channel between dual CPU and status of processor itself. We find out the ideal value of threshold and priority for load test task. and we evaluate the accuracy of the proposed S/W Watch-Dog Method at the result of evaluation. We figure out that the accuracy of proposed method is higher than the accuracy of general S/W Watch-Dog Method in case of variable data rate. Therefore we confirm that the proposed Method has high accuracy of watch-dog function with the ideal value of threshold and priority for load test task through the performance evaluation.

• The Transactions of the Korea Information Processing Society
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• v.4 no.5
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• pp.1196-1210
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• 1997

Timestamp-Ordering Prltocol among trancaction scheduling alforithms can cause the priority teversion that a transaction with higher priority is processed after the teansaction the trancaction withe lower priority by assigning timestamp to transactions entering system and scheduling them based on the timestamp.To prevent this reversion,we suggest a data priority-based timestamp ordering prioity within the same timestamp group after grouping teansactions into constant time interval based on entering points.To evaluate the performance of this protocol,we compared the performance of this protocol with that of others after constructing the simulation environment with real time database system.We verified that the performance of proposed protocol is supweior to that of timestamp ordering protocol under the comdition of high load and high data conflicts.