• Journal of Korean Library and Information Science Society
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• v.34 no.2
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• pp.19-42
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• 2003

The purpose of this study is to identify the way of development of school library and construction of information system for school library. In order to identify the way, the school librarian recognition level of school library information system was analyzed, since the recognition level about the information system can affect the school library development. Data is collected through the questionnaire. The result can be used to develope a school library instruction program for teachers and a base material for recovering the school library fundamental function.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.13-21
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• 2004

This paper deals with a theoretical and experimental method for the design of a biased asymmetric pre-swirl stator propulsion system which is an energy saving device by recovering a propeller rotational energy. In the case of slow-speed ships, the upward flow is generated along the afterbody hull form at the propeller plane. The generated upward flow cancels the rotating flow of the propeller at the starboard part while it increases at port part. The present biased asymmetric pre-swirl stator propulsion system consists of three blades at the port and one blade at the starboard which can recover the biased rotating flow effectively. This paper provides the design concept which gives more simple and a high degree of efficiency and the experimental results for the compound propulsion system.

• International Journal of Naval Architecture and Ocean Engineering
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• v.1 no.1
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• pp.29-38
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• 2009

A ship's screw-propeller produces thrust by rotation and, at the same time, generates rotational flow behind the propeller. This rotational flow has no contribution to the generation of thrust, but instead produces energy loss. By recovering part of the lost energy in the rotational flow, therefore, it is possible to improve the propulsion efficiency. The contra-rotating propeller (CRP) system is the representing example of such devices. Unfortunately, however, neither a design method nor a full-scale performance prediction procedure for the CRP system has been well established yet. The authors have long performed studies on the CRP system, and some of the results from the authors' studies shall be presented and discussed.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.212-222
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• 2000

This study was performed to investigate the performance of heat recovery device attached to exhaust gas flue connected to combustion chamber of greenhouse heating system. The experimental heat recovery system is mainly consisted of LPG combustion chamber and two heat recovery units; unit-A is attached directly to the exhaust gas flue, and unit-B is connected with unit-A. Heat recovery performance was evaluated by estimating total energy amounts by using enthalpy difference between two measurement points together with mass flow rate of gas and/or air passing through each heat recovery unit depending on 5 different flow rates controlled by voltage meter. The results of this experimental study, such as heat exchange behavior of supply air tubes and exhaust air passages crossing the tubes, pressure drop between inlet and outlet, heat recovery performance of exchange unit, etc., will be used as fundamental data for designing optimum heat recovery device to be used for fuel saving purpose by reducing heat loss amounts mostly wasted outside of greenhouse through flue.

• Journal of the Korea Computer Industry Society
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• v.3 no.7
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• pp.921-926
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• 2002

B+-Tree is the most popular indexing method in DBMS to manage large size data in more efficiency. However the existing B+-Tree has shortcomings in there is overhead on DISK/IO when the first time of constructing DB or of making Index, and it lessens the concurrency if there are frequent delete operations so that the index structure also should be changed frequently. To solve these problems almost DBMS is using batch construction method and lazy deletion method. But to apply B+-Tree, which is using batch construction method and lazy deletion method, into DBMS the technique for controlling and recovering concurrency is necessary, but its researching is still unsatisfactory so that there is a problem on applying it into actual systems. On this paper I suggest the technique for controlling and recovering concurrency how to implement the batch construction method and the lazy deletion method in actual DBMS. Through the suggested technique there is no cascade rollback by using Pending list, it enhances the concurrency by enabling insertion and deletion for base table on every reconstruction, and it shortens transaction response time for user by using system queue which makes the batch constructing operation is processed not in user's transaction level but in system transaction level.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.117-119
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• 2004

In order to successfully exploit underwater resources, the first step would be a marine environmental research and exploration on the seafloor. Traditionally one sets up a long-term underwater experimental unit on the seafloor and retrieves the unit later after a certain period time. Essential to these applications is the reliable teleoperation and telemetering of the unit. This study presents ultrasonic-wave remote control system and an underwater sound recognition algorithm that can identify the sound signal without the influence of disturbances due to underwater environmental changes. The proposed method provides a means suitable for units which require low power dissipation and long-time underwater operation. We demonstrate its ability of securing stability and fast sound recognition through experimental methods.

• 시스템엔지니어링워크숍
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• s.4
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• pp.108-112
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• 2004

The Smart UAV Program was motivated by a huge potential market, a various application and future core technologies. The Smart UAV system is defined as the advanced air vehicle with the smart technology such as collision awareness and avoidance, healthy monitering and self-recovering, intelligent active control. Due to the broad interest by government, industry and academia, Smart UAV development center and government steering committee were established. The organization of Smart UAV program consists of domestic/international companies and academia. in this paper, the process and application of system engineering was introduced for Smart UAV development program.

• Journal of Advanced Navigation Technology
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• v.18 no.1
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• pp.74-77
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• 2014

This paper suggested an error control for multi-channel running on machine to machine environment. This system is suitable for recovering software fault for multimedia CSCW(Computer Supported Cooperative Works) based on machine to machine environment. It is necessary for the system to be protected by reactivity of media service instance instead of breaking process of session. This paper explains a performance analysis of an error recovery system of M2M based computing collaboration environment using rule-based DEVS modeling and simulation techniques.

• Journal of the Korean Society of Systems Engineering
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• v.1 no.2
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• pp.49-55
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• 2005

The Smart UAV Program was motivated by a huge potential market, a various application and future core technologies. The Smart UAV system is defined as the advanced air vehicle with the smart technology such as collision awareness and avoidance, healthy monitering and self-recovering, intelligent active control. Due to the broad interest by government, industry and academia, Smart UAV development center and government steering committee were established. The organization of the Smart UAV program consists of domestic/international companies and academia. In this paper, the process and application of system engineering was introduced for Smart UAV development program.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.10 no.2
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• pp.5-32
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• 2004

We have studied the effect and application of CST which is the function and disease of the autonomic nerve system based on recovery of flexibleness of the autonomic nerve. CST purpose to keep sustenance of human body by recovering joints have limitation of mobility and controlling autonomic nerve system by diminution tense of the sympathetic nerve. CST makes well flowing of CSF by pressure the fourth ventricle of the brain or relaxation of soft tissues of the base of a cranial bone. There is no result of studies about CST in Korea yet. It will bring a benefit if it prove the effect of CST in countries depend on drugs way high such as Korea. It needs positive approach and definite research for the improvement.