• Journal of Power System Engineering
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• v.15 no.2
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• pp.78-83
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• 2011

This paper aims at investigation some operating characteristics and energy usage efficiency of a induction motor and a BLDC motor considering electric propulsion system in a small ship based on battery source. At first, performance curves of discharge voltage from the battery and current from each motor according to the load variations were analyzed. Next, variations of motor torque and rotational speed versus load change at each motor were analyzed. Finally, efficiency of energy usage of the battery and available navigation distance were compared each other. Through some comparisons and analyses, it was cleared that the BLDC motor is more suitable for the motor of the electric propulsion system in small ships based on battery source. It is expected that the results can be used as useful data for design of the electric propulsion system with batteries.

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.3
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• pp.191-208
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• 1997

Recently, self-efficacy is one of the critical constructs that have been found to influence human decisions about behavior selection and the performance associated with the selected behavior. The construct has been widely adaopted and tested in the fields of social psychology and/or other behavioral sciences. In information system field, however, it has been hardly studied, although computer self-efficiency could have been an important factor explaining and predicting human computer usage behaviors. From this perspective, main proposes of the study are : (1) to develop a measure of computer self-efficacy, 2) to identify the factors influencing self-efficacy, and 3) to reveal the relationship between self-efficacy and computer usage behavior. By reviewing the literature, past experience, others'use, encouragement by others, and anxiety are selected as the factors influencing computer self-efficacy. Four hypotheses concerning the relationship between each of the variables and computer self-efficacy are tested by LISREL. One more hypothesis about the relationship between computer self-efficacy and computer usage is also tested. The results show that computer self-efficacy is significantly influenced by computer ansiety, encouragement by others, and computer experience, and that it is closely correlated with computer usage behavior.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.1
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• pp.37-45
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• 2022

With the development of the 4th industry, big data using AI is being used in many areas of our lives, and the importance of data is increasing accordingly. In particular, as various services using personal information appear and hacking attacks that exploit them appear in various ways, the importance of personal information management is increasing. Personal information must be managed safely even when collecting, retaining, using, providing, and destroying personal information, and the rights of information subjects must be protected. In this paper, an analysis was performed on the notification of usage history during the protection of the rights of information subjects using the MyData model. According to the Personal Information Protection Act, users must be periodically notified of the use of personal information, so we notify each individual of the use of personal information through e-mail or SNS once a year. It is difficult to understand and manage which company use my personal information. Therefore, in this paper, a personal information usage history notification system model was proposed, and as a result of performance analysis, it is possible to provide the controllability, availability, integrity, source authentication, and personal information self-determination rights.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.5
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• pp.638-644
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• 2010

This paper presents ideas of service scenarios for home residents using electric power monitoring system per appliance, the implementation of the monitoring system, and analysis of acquired electric power usage pattern. By acquiring and analyzing electric power usage pattern, home residents can get information of power usage pattern of every legacy (non-Demand Response-ready) appliance. Further they can get pieces of recommendation how to reduce energy consumption, intelligent standby power blocking service, and alarming service to abnormality of appliances. In order to check the feasibility of the ideas, a system that can acquire electric power pattern per appliance is implemented, and electric power pattern of some appliances are stored to a database and it was analyzed to show if auto-identification of a type of a device is possible, which is a basic required function for the scenarios presented.

• Journal of the Korean Society for information Management
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• v.5 no.2
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• pp.145-160
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• 1988

111 this paper, ~vc atialyzed thr, staristical data logged by rlte library itiformatio~~ rrtrieval system n41icli was developed it1 K'I'A as a part of total system. System performance was measured numerically b\. means of tables and graphs reprc.ieritmg the usage patterns, die response times, and tl~e success ratt.5 of each stxiircIii~rg item.

• Asia pacific journal of information systems
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• v.15 no.1
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• pp.1-24
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• 2005

The purpose of this study is to identify the factors affecting the performance of knowledge management systems. To extend DeLone & MeLean's model, we included the user specialization in the information systems success model. The questionnaires are collected from 109 knowledge management system users. The major findings are summarized as followed. First, system characteristics such as ease of use, response time, and knowledge management process support affect the knowledge management systems usage. Second, knowledge characteristics such as relevancy, completeness, reliability, importance, and currency also affect the knowledge management systems usage. Third, the end-users are satisfied with the knowledge management systems because it is easy to use and relevant.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.4
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• pp.39-45
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• 2011

Application log files contain error messages; operational data and usage information that can help manage applications and servers. Log analysis system is software that read and parse log files, extract and aggregate information in order to generate reports on the application. In currently, the importance of log files of firewalls is growing bigger and bigger for the forensics of cyber crimes and the establishment of security policy. In this paper, we designed and implemented the SILAS(SysLog-based Integrated Log mAanagement System) in distribute network environments. It help to generate reports on the the log fires of firewalls - IP and users, and statistics of application usage.

• Journal of Platform Technology
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• v.11 no.6
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• pp.3-12
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• 2023

In today's system operation, it is difficult to detect failures and take immediate action in the case of a shortage of manpower compared to the number of equipment or failures in vulnerable time zones, which can lead to delays in failure recovery. In addition, various algorithms exist to detect abnormal symptom data, and it is important to select an appropriate algorithm for each problem. In this paper, an ensemble-based isolation forest model was used to efficiently detect multivariate point anomalies that deviated from the mean distribution in the data set generated to predict system failure and minimize service interruption. And since significant changes in memory space usage are observed together with changes in CPU usage, the problem is solved by using LSTM-Auto Encoder for a collective anomaly in which another feature exhibits an abnormal pattern according to a change in one by comparing two or more features. did In addition, evaluation indicators are set for the performance evaluation of the model presented in this study, and then AI model evaluation is performed.

• Journal of Internet Computing and Services
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• v.16 no.3
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• pp.95-104
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• 2015

In recent years, in accordance with the rapidly increasing number of smartphone users, various social problems have started to occur. Examples of these problems are the overuse of smartphones and bad usage habits of smartphone users that can cause new social problems such as smartphone addiction and other smartphone related diseases. With the aim of preventing these social problems, this paper proposes a new smartphone addiction and disease prevention system. This system was developed by collecting and analyzing smartphone usage patterns. This proposed system analyzes the usage patterns and working hours of smartphone users in real time. If the detected smartphone usage patterns reach a dangerous level, the system will send warning messages to the user. This will enable users to recognize the unhealthy situation in advance by themselves. In addition, this solution could possibly prevent smartphone addiction and other smartphone related illness by preventing overuse and encouraging abstinence from using smartphones to the extent that it becomes harmful to the user.

• The Journal of Korean Physical Therapy
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• v.30 no.2
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• pp.54-57
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• 2018

Purpose: Most studies have reported pain in the head-neck and upper-limbs according to smartphone usage, which is related to the proprioception sense in the head and neck, but there have been few studies. Therefore, the aim of this study was identify the adverse effects of the proprioceptive sense in the head-neck according to smartphone usage. Methods: Twenty-seven young adults (male: 9, female: 18) were enrolled in this study. The proprioceptive sense was measured through the joint reposition sense error and neural positon error in the head-neck during smartphone usage for 0, 5, and 20 minutes. The Noraxon MyoMotion system was used to record the joint position angle and neutral positon in the head-neck. One-way repeated ANOVA was used to identify the differences between the three smartphone use durations and the least-squares difference was used as a post hoc test. The data were analyzed using SPSS 18.0 software. Results: The joint reposition sense error and neural positon error in the head-neck were significantly different among the 0, 5, and 20 minutes of smartphone usage (p<0.05). In the post hoc test, the joint reposition sense error and neural positon error showed a significant difference between smartphone use for 0 minute and 5 minute, and between smartphone use for 0 minute and 20 minutes. Conclusion: This study suggests that smartphone use within 5 minutes can have adverse effects on the proprioceptive sense. Therefore, it is necessary to consider the appropriate use time and break time when using smart phones.