• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1097-1100
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• 2003

Data Loggers for environmental monitoring are mostly dispersion in installation and systems located at long distance from monitoring system. And, it requests mostly flexible functions and high performances. that can fit to various sensor inputs, sensor interfaces and conditions or system working. In this research, we developed the micro controller based Data Logger with minimum hardware construction that allows the higher flexibility of application. Finally, we developed software function for water quality monitoring and tested in real system launched at Han river.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.791-799
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• 2005

We consider two components parallel system in which the lifetimes have the bivariate Pareto model with bivariate random censored data. We assume that bivariate Pareto model is affected by common stress which is independent of the lifetimes of the components. We obtain estimators for the system reliability based on likelihood function and relative frequency. Also we construct approximated confidence intervals for the reliability based on maximum likelihood estimator and relative frequency estimator, respectively. Finally we present a numerical study.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.12
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• pp.1777-1783
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• 2013

This study aims to implement an instrumentation system measuring and analysing real-time data of information flow between respective subunits composing train control system as the performance evaluation method for wireless communication based urban railway train control system under development for a Korean model. It analyses system functional requirements regarding subsystems composing wireless communication based train control system and test items for functions presented in each specification and examines data and measurement point for measuring according to test items in order to implement an instrumentation system. And, it clearly defines requirements of an instrumentation system to avoid malfunction or error in operation of train control system. It reviews data processing method and display method for effective analysis of data flow between respective subunits with measured data, designs and makes an instrumentation system. Ultimately, it applies to a performance test of train control system and makes sure an instrumentation system in normal working order.

• Journal of Power System Engineering
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• v.18 no.3
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• pp.73-78
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• 2014

Recently, Free cooling system usage has increased at many buildings in intermediate and winter season. Free cooling system is used to reduce the energy consumption of refrigeration in that season. Free cooling system is refrigeration system using cooled water. In general, this system is applied with the building having refrigeration load at all time such as a data center. In this study, energy consumption of a data center taking free cooling system in Ulsan was evaluated by the software HYSYS. the main result is as in the following : free cooling system is effective from January to April and from November to December. In case of Ulsna in 2013, using free coolng system is able to spend refrigeration energy of about 15% less than existing system. According to this result, it is appropriated that free cooling system is used in building having refrigeration load at all time such as data center.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.743-746
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• 1998

In this paper, we developed an outdoor augmented reality system which has remote real scences acquisition ability. The real scenes acquisition system consists of image acquisition system, tracking system, wireless data transceiver and power supply. Tracking system that consists of Tans Vector and RT-20 measures a position and attitude of the CCD camera that attached at the remote control helicopter. Wireless data transceiver system is utilized for data transmission of remote system that of attitude, position information, andreal scenes data that acquired by the CCD camera. Maximum propelling power of remote control helicopter is 15Kg, so we used 7.2V li-ion cell as a power supply for system minimize. As the results of experiment, the developing system presented application possibility of remote information acquisition system such as construction simulation & estimation, broadcasting, tour guide.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.615-616
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• 2006

Many manufacturing companies manage their production-related data for quality management and production management. Nevertheless, production related-data should be closely related to each other Stored data is mainly used to monitor their process and products' error. In this paper, we provide an enterprise-wide production data model for decision support system and product automation. Process data, quality-related data, and test data are integrated to identify the process inter or intra dependency, the yield forecasting, and the trend of process status. In addition, it helps the manufacturing decision support system to decide critical manufacturing problems.

• Journal of Information Technology Services
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• v.8 no.1
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• pp.179-192
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• 2009

In wireless environments, it is very effective to introduce a data broadcast system for providing a number of clients with mobile data services. In particular, an efficient broadcast scheduling and a caching strategy are very important for performance of data broadcast systems in wireless environments which have such inherent restrictions as low bandwidth, frequent disconnections, and short battery life. In this paper, we present a data broadcast scheduling strategy using bit vectors to cope with dynamic request patterns of clients. In addition, we also propose an efficient caching strategy, 2FWT, that takes characteristics of the broadcast scheduling strategy into account. Finally, we evaluate performance of the data broadcast system. According to the results, the proposed system generally shows better performance than others.

• International journal of advanced smart convergence
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• v.13 no.3
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• pp.135-142
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• 2024

Recently, along with digital transformation, technologies such as cloud computing, big data, and artificial intelligence have been actively introduced. In a situation where these technological changes are progressing rapidly, it is often difficult to manage processes efficiently using existing simple workflow management methods. Companies providing current cloud services are adopting virtualization technologies, including virtual machines (VMs) and containers, in their distributed system infrastructure for automated application deployment. Accordingly, this paper proposes a process-based orchestration system for integrated execution of corporate process-oriented workloads by integrating the potential of big data and machine learning technologies. This system consists of four layers as components for performing workload processes. Additionally, a common information model is applied to the data to efficiently integrate and manage the various formats and uses of data generated during the process creation stage. Moreover, a standard metadata protocol is introduced to ensure smooth exchange between data. This proposed system utilizes various types of data storage to store process data, metadata, and analysis models. This enables flexible management and efficient processing of data.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.4
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• pp.598-604
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• 2022

The academic information system of a university is the core system of the university, and since it has to manage all the various activities in the university, such as student academic records, it becomes complicated every year and the data increases indiscriminately. As a result, the reliability of the data of the academic information system is lowered, which causes communication problems with users and may cause a major failure in the system. Therefore, in this paper, column attribute analysis, allowable value list analysis, string pattern analysis, date type analysis, and unique value analysis methods were designed for the academic information system using the data profiling technique of data quality management. In the implementation stage, the script was implemented using the above five analysis methods, and by executing the script, errors by type of the academic information system were found, the cause of the error was found and corrected inside the system, and the probability of internal system failure was lowered.

• Spatial Information Research
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• v.12 no.3
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• pp.275-283
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• 2004

In order to effectively, and accurately assess seawater intrusion in coastal area, multidisciplinary data including geophysical, well logging, and hydrogeochemical data should be managed in systematical way. Such systematical management of data is critical key to improve the re-usability of the data as well as the accuracy of the assessment by means of providing a method of synthetic analysis. Therefore, for systematical management of multidisciplinary data in seawater intrusion problem, we have developed a database management system and 3-D visualization interface based on geographic information system in this, study. All geophysical survey, well logging, hydrochemical, as well as drilling, data are classified as attribute data using Microsoft Access, and joined with spatial information based on ArcView. The database management system and 3-D visualization interface to handle these data, also, developed using the script language of ArcView. We think the development of database and 3-D visualization system will improve the efficiency of data management, user-friendliness of data access, and accuracy of data analysis.