• Journal of Information Processing Systems
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• v.7 no.4
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• pp.613-626
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• 2011

In this paper, we focus on the pinwheel task model with a variable voltage processor with d discrete voltage/speed levels. We propose an intra-task DVS algorithm, which constructs a minimum energy schedule for k tasks in O(d+k log k) time We also give an inter-task DVS algorithm with O(d+n log n) time, where n denotes the number of jobs. Previous approaches solve this problem by generating a canonical schedule beforehand and adjusting the tasks' speed in O(dn log n) or O($n^3$) time. However, the length of a canonical schedule depends on the hyper period of those task periods and is of exponential length in general. In our approach, the tasks with arbitrary periods are first transformed into harmonic periods and then profile their key features. Afterward, an optimal discrete voltage schedule can be computed directly from those features.

• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1201-1210
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• 2000

In order to tolerate faults which may occur during the execution of distributed tasks in high-performance parallel computer systems, tasks are duplicated on different processors. In this paper, by utilizing the task duplication based scheduling algorithm, a new task scheduling algorithm which duplicates each task on more than two different processors with the minimum schedule length is presented, and the number of processors required for the duplication is analyzed with the ratio of communication cost to computation time and the workload of the system. A simulation with various task graphs reveals that the number of processors required for the full-duplex fault-tolerant task scheduling with the obtainable minimum schedule length increases about 30% to 75% when compared with that of the task duplication based scheduling algorithm.

• Journal of Computing Science and Engineering
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• v.10 no.1
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• pp.9-20
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• 2016

Several task clustering heuristics are proposed for allocating tasks in heterogeneous systems to achieve a good response time in data intensive jobs. However, one of the challenging problems is the process in task scheduling after task allocation by task clustering. We propose a task scheduling method after task clustering, leveraging worst schedule length (WSL) as an upper bound of the schedule length. In our proposed method, a task in a WSL sequence is scheduled preferentially to make the WSL smaller. Experimental results by simulation show that the response time is improved in several task clustering heuristics. In particular, our proposed scheduling method with the task clustering outperforms conventional list-based task scheduling methods.

• Journal of Information Processing Systems
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• v.10 no.2
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• pp.193-214
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• 2014

Load balancing is the major benefit of any distributed system. To facilitate this advantage, task duplication and migration methodologies are employed. As this paper deals with dependent tasks (DAG), we used duplication. Task duplication reduces the overall schedule length of DAG along-with load balancing. This paper proposes a new task duplication algorithm at the time of tasks assignment on various processors. With the intention of conducting proposed algorithm performance computation; simulation has been done on the Netbeans IDE. The mesh topology of a distributed system is simulated at this juncture. For task duplication, overall schedule length of DAG is the main parameter that decides the performance of a proposed duplication algorithm. After obtaining the results we compared our performance with arbitrary task assignment, CAWF and HEFT-TD algorithms. Additionally, we also compared the complexity of the proposed algorithm with the Duplication Based Bottom Up scheduling (DBUS) and Heterogeneous Earliest Finish Time with Task Duplication (HEFT-TD).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.161-162
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• 2023

The construction inspection is conducted by the contractor or construction supervisor after a certain stage of work has been completed. As the consturction inspection task is dependant on construction schedule, however, it is difficult to plan inspection task systematically, resulting in increased supervision costs, delays in construction, and disputes. Therefore, this study aims to integrate inspection work with schedule management to systematize inspection procedures. Firstly, the inspection work is defined based on the construction supervision checklist. Then its relationship with the construction process, required time, and resources for inspection tasks are defined in construction schedule. Lastly, a process management program is used to assess the effects of applying the inspection work and examine changes in the overall construction period and process management. The proposed method in this study can support to plan construction inspection more systematically and to improve the effectiveness of construction quality management.

• Science of Emotion and Sensibility
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• v.17 no.1
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• pp.3-12
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• 2014

Quick and accurate learning of diverse electronic products has become an important daily task. In particular, software occupies core status in the control and operation of the products. This research tested the effects of learning method, schedule, and task difficulty in the learning of software. Using 2 (learning method: experiential vs. verbal) ${\times}$ 2 (learning schedule: spaced vs. massed) ${\times}$ 2 (difficulty: easy vs. difficult) between-subjects design, Experiment 1 tested participants' learning of file control using Windows Movie Maker. There was no effect of learning schedule on task completion time, but participants in experiential learning were faster in the completion of evaluation task compared with those in verbal learning condition. Importantly, as task difficulty increases participants in verbal condition showed markedly lower performance than those in experiential condition, which suggests that experiential learning is more effective with more difficult learning task. That is, in case of learning simple operation of software verbal learning using linguistic manual or instruction could be sufficient; on the other hand in case of learning complex operation learning from experience or tutorial mode would be more effective. Additional studies which manipulated task difficulty (Expt. 2) and inter-trial learning interval (Expt. 3) did not produce meaningful results.

• Journal of the Korea Society of Computer and Information
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• v.4 no.4
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• pp.40-46
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• 1999

The task scheduling has an effect on system execution time in a precedence constrained task graph onto the multiprocessor system. This problem is known to be NP-hard. many people made an effort to obtain near optimal schedule. We compared modified critical path schedule with many other methods(CP, MH, DL Swapping) For testing this subject, we created randomly a directed acyclic task graph with many root nodes and terminal nodes simulation result convinced for us that the modified critical path algorithm is superior to the other scheduling algorithm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1281-1286
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• 2009

Our government operates earned value management system (EVMS)of construction schedule and cost for improving earned management system of the construction projects. but There is two unification Method construction schedule and cost to estimate construction progress currently. This weight a staff work. therefore this study present unification method which operate integrate schedule and cost by using work task. In order to inflect verification and model of schedule and cost, this study develop prototype of EVMS.

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.6
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• pp.367-372
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• 2013

Cloud computing technology has been developing at an increasing expansion rate. Today most of firms are using this technology, making improving the quality of service one of the most important issues. To achieve this, the system must operate efficiently with less idle time and without deteriorating the customer satisfaction. This paper focuses on enhancing the efficiency of a conventional Genetic Algorithm (GA) for task scheduling in cloud computing using Fuzzy Logic (FL). This study collected a group of task schedules and assessed the quality of each task schedule with the user expectation. The work iterates the best scheduling order genetic operations to make the optimal task schedule. General GA takes considerable time to find the correct scheduling order when all the fitness function parameters are the same. GA is an intuitive approach for solving problems because it covers all possible aspects of the problem. When this approach is combined with fuzzy logic (FL), it behaves like a human brain as a problem solver from an existing database (Memory). The present scheme compares GA with and without FL. Using FL, the proposed system at a 100, 400 and 1000 sample size*5 gave 70%, 57% and 47% better improvement in the task time compared to GA.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.703-704
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• 2011