• Asia pacific journal of information systems
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• v.12 no.4
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• pp.77-99
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• 2002

This study compares avatar-based chatting and text-based chatting. The comparison focuses on the effect of different chatting methods on user perception such as flow, social presence, and media richness. Especially the effects of avatar are examined across varying task types-work-oriented and fun-oriented. To accomplish this objective, a laboratory experiment was conducted using 80 experienced subjects. The results indicate that avatar-based chatting was more playfulness than text-based chatting in general. However, the effects of chatting methods on user perception were quite different according to the task types. There was no significant difference between avatar-based chatting and text-based chatting in the fun-oriented task, but avatar-based chatting was perceived as a more playful, focused, telepresent, and social present method in the work-oriented task.

• Journal of Internet Computing and Services
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• v.12 no.6
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• pp.1-17
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• 2011

The performance of DHCS depends on the algorithm which schedules input DAG. However, as the task scheduling problem in DHCS is an NP-complete problem, heuristic approach has to be made. Task scheduling algorithm consists of task prioritizing phase and processor allocation phase, and most of studies are considering both phases together. In this paper, we focus on task prioritizing phase and propose a WPD algorithm which is optimized for task duplication based processor allocation method. For an evaluation of the proposed WPD algorithm, we combined WPD algorithm with processor allocation phase of HMPID, HCPFD, HCT algorithms, which are using task duplication based processor allocation method. The results show that WPD algorithm makes a better use of task duplication than conventional task prioritizing methods and provides 9.58% better performance than HCPFD algorithm, 1.31% than HCT algorithm.

• Science of Emotion and Sensibility
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• v.5 no.2
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• pp.63-72
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• 2002

In order to examine universal design, 1 have developed two analytical methodologies based on 3P(point) task analysis: structured task analysis and task matrix analysis. I also extracted nine universal design items, namely (1) adjustment, (2) redundancy, (3) specification and function transparency, (4) feedback and (5) error tolerance, (6) effective acquisition of information, (7) ease of understanding and judgment, (8) comfortable operation, and (9) continuity of information and operation. Structured task analysis is used to uncover problems in each of the tasks constituting a job for each functionally challenged condition of users, and solutions to the extracted problems are examined in terms of the above-mentioned nine universal design items. Task matrix analysis calls for the production of a table for each task in a job. In each table, nine items form the columns, and the horizontal rows list all disability types. Then, solutions are formulated for each cell formed by the intersecting columns and rows. Using these two analysis methods, 1 have conducted a verification experiment for the universal design of a public bus. The results of the research have enabled me to propose various ,solutions from a system-based perspective, instead of coming up with the superficial and isolated solutions which are normally produced when conventional analytical methods are used.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.144-151
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• 2002

In order to examine universal desist I have developed two analytical methodologies based on 3P(point) task analysis: structured task analysis and task matrix analysis. I also extracted me universal design items, namely (1) adjustment (2) redundancy, (3) specification and function transparency, (4) feedback and (5) error tolerance, (6) effective acquisition of information, (7) ease of understanding and judgment (8) comfortable operation, and (9) continuity of information and operation. Structured task analysis is used to uncover problems in each of the tasks constituting a job for each functionally challenged condition of users, and solutions to the extracted problems are examined in terms of the above-mentioned nine universal design items. Task matrix analysis calls for the production of a table for each task in a job. In each table, nine items from the columns, and the horizontal rows list all disability types. Then, solutions are formulated for each cell formed by the intersecting columns and rows. Using these two analysis methods, T have conducted a verification experiment for the universal design of a public bus. The results of the research have enabled me to propose various solutions from a system-based perspective, instead of coming up with the superficial and isolated solutions which are normally produced when conventional analytical methods are used.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1204-1208
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• 2007

In order to prevent railway accidents due to human errors which have been recognized to be the most important cause in the railway accidents, human errors should have been controlled based on systematical analysis of the human errors, and countermeasures should be derived to reduce human error probability. Among several factors inducing human errors, task load (or task complexity) is representative. In order to reduce the human error, a systematic analysis should be undertaken to evaluate task load. In this study, task load according to task types of railway worker who are a safety critical staff have been quantitatively analyzed based on NASA-TLX(Task Load Index).

• 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 Information Technology Services
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• v.9 no.4
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• pp.169-185
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• 2010

According to software growth, also software maintenance has been continuously improving. In addition, the existing concept of software maintenance process demands operational management and improvement of service task. However, when we perform maintenance task, we have several constraints about applying service based requirement to system. Therefore, in order to solve these problems, we need a study of task of process for service based maintenance. In this paper, we propose a Service based Software Maintenance Process. Proposed process based on MaRMI-RE standard for software development and maintenance and compares it with the service based representative standards. In a related works, we study activity of ITIL and identify activities and tasks for maintenance. After this, identified activities and tasks compare with activities of MaRMI-RE. And then, we derive activities and tasks of a Service based Software Maintenance Process. Finally, we validate a result by comparing the proposed process with a general service operational process.

• The Journal of Korean Physical Therapy
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• v.24 no.6
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• pp.405-408
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• 2012

Purpose: We examined the effect of dual-task and single-task training on serial reaction time (SRT) task performance to determine whether SRT is based more on motor or perception in a dual-task. Methods: Forty healthy adults were divided into two groups: the dual-task group (mean age, $21.8{\pm}1.6$ years) and the single-task group (mean age, $21.7{\pm}1.6$ years). SRT task was conducted total 480 trial. The four figures were presented randomly 16 times. A unit was set as 1 block that would repeat 10 times. Thus, there were a total of 160 trials for each of the three color conditions. The dual-task group performed an SRT task while detecting the color of a specific shape. The end of the task, subjects answered the specific shape number; the single-task group only performed the SRT task. The study consisted of three parts: pre-measurement, task performance, and post-measurement. Results: Differences of pre and post reaction time between two group was higher for the dual-task group as compared to the single task group and there was a significant interaction between time and group (p<0.05). Conclusion: Our results indicate that. short term period SRT is not quiet effective under dual-task conditions, individuals need additional cognitive processes to successfully navigate a task This suggests that dual-task training might not be appropriate for motor learning enhancement, at least when the training is over a short period.

• 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 the HCI Society of Korea
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• v.6 no.1
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• pp.17-20
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• 2011

The contingency theory of leadership was proposed by F. Fiedler. In his theory, he divided the group into Task oriented and Relationship-oriented people based on work-style by LPC(Least Preffered Co-workers) test. This survey searches significance of interaction usage depending on which group has more aggressive interaction on the address list with mobile phones focusing on the differences between mainfunctions (name, cell phone, group name) and sub-functions (birthday, Photo, E-mail). Itis the hypothesis that the relationship-oriented group has more interaction than the task-oriented group which was identified through the analyzed usage of the address list. Results show that the contingency theory was not appropriately related with the research. Interaction usage by the following task based on Fiedler's contingency theory of leadership isn't related much. However, by discovering the interesting patterns by the test, this research is able to guide human-centered address design directions.