• Fashion & Textile Research Journal
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• v.1 no.2
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• pp.154-159
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• 1999

In this study, for different test methods of the performance of sewing threads were used to evaluate the sewability of 10 different industrial threads. Sewability evaluations related to the breakage of thread during sewing operation were investigated by seam length and fabric thickness method (Test 1), thread tension method (Test 2), strength retention method (Test 3), and backward sewing method(Test 4), and discussed. Two of the methods, Test 1 and Test 2, simulated very harsh sewing conditions which each thread could accept as an evaluation of its sewability. Core spun thread ranked with the best sewability generally and followed by air jet textured (ATY) thread. Spun thread was superior to the filament thread in sewing thread type. In general, there was a high degree of correlation in the results of Test 1 and Test 2. The order of sewing thread by sewability test 1 was polyester spun thread, cotton thread, and p/c core spun thread. The order of sewing thread by test 2 was polyester spun thread, and p/c core spun thread. Cotton threads and cotton blended threads performed better in Test 3, and ATY threads and core spun threads in Test 4.

• Journal of Satellite, Information and Communications
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• v.8 no.2
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• pp.80-87
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• 2013

Communication Ocean Meteorological Satellite (COMS) has the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service. The COMS is located at $128.2{\circ}$ east longitude on the geostationary orbit and currently under normal operation service since April 2011. In order to perform the three missions, the COMS has 3 separate payloads, the meteorological imager (MI), the Geostationary Ocean Color Imager (GOCI), and the Ka-band communication payload. The satellite controls for the three mission operations and the satellite maintenance are done by the real-time operation which is the activity to communicate directly with the satellite through command and telemetry. In this paper the real-time operation for COMS is discussed in terms of the ground station configuration and the characteristics of daily, weekly, monthly, seasonal, and yearly operation activities. The successful real-time operation is also confirmed with the one year operation results for 2011 which includes both the latter part of the In-Orbit-Test (IOT) and the first year normal operation of the COMS.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.157-163
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• 2002

Consideration for parallel operation in a high power system has been increased due to the advantages of parallel operation like as high productivity, simplicity of design, and redundancy of power. This paper discussed the parallel operation of DC-DC Converter, Which Can be used as a high power system, is studied. Based on the small signal model of DC-DC Converter, the simple and exact power stage model of parallel operation system is derived and the parallel operation system using current balance method for the uniform current distribution among the parallel operation system is discussed. To verify the high performance of the proposed DC-DC converter system for parallel operation, the simulation test of the parallel operation, which has 2 Converter modules, is accomplished.

• Korean Management Science Review
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• v.26 no.1
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• pp.113-126
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• 2009

By the newly emerging network access technology, we face the new heterogeneous network environment. Focusing on the co-existence of multiple access network technology and the complex service needs of users, the wireless service operators should present the stable service quality for every user. For this, the service operators should build the new operation framework which combine the pre-established network and newly adopted one. Our problem is finding the optimal heterogeneous network operation framework. We suggest market-based marginal cost function for evaluating the relative value of resource of each network and develop the whole new heterogeneous network operation framework. To test the applicability of developed operation framework, we build large-scale JAVA simulator. By this development, we can easily test the new network environment in practical engineering field.

• Korean Journal of Remote Sensing
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• v.15 no.4
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• pp.357-365
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• 1999

The optical sensors of Electro-Optical Camera (EOC) and Ocean Scanning Multi-spectral Imager (OSMI) aboard the KOrea Multi-Purpose SATellite (KOMPSAT) will be placed in a sun synchronous orbit in late 1999. The EOC and OSMI sensors are expected to produce the land mapping imagery of Korean territory and the ocean color imagery of world oceans, respectively. Utilization of the EOC and OSMI data would encompass the various fields of science and technology such as land mapping, land use and development, flood monitoring, biological oceanography, fishery, and environmental monitoring. Readiness of data support for user community is thus essential to the success of the KOMPSAT program. As a part of testing such readiness prior to the KOMPSAT launch, we have performed the preliminary acceptance test for the KOMPSAT data processing system using the simulated EOC and OSMI data sets. The purpose of this paper is to demonstrate the readiness of the KOMPSAT data processing system, and to help data users understand how the KOMPSAT EOC and OSMI data are processed, archived, and provided. Test results demonstrate that all requirements described in the data processing specification have been met, and that the image integrity is maintained for all products. It is however noted that since the product accuracy is limited by the simulated sensor data, any quantitative assessment of image products can not be made until actual KOMPSAT images will be acquired.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.110.1-110.1
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• 2011

This study analyzed the performance of long term operation photovoltaic system The 50 kWp grid connected photovoltaic system which was installed at KEPRI site in 1999 has been operated more than 12 years. In order to acquire long term operation characteristics of medium size photovoltaic system, the operation test data related on power generation electricity and capacity factor of 50 kWp system, which have been collected since 1999, were analysed. From the analysing results, 57.7 MWh in annual power generation electricity of 50 kWp photovoltaic system in 1999 has been decreased 49.1 MWh in 2005 and reached 38.0 MWh in 2010. In addition to, the capacity factor of 50 kWp photovoltaic system also showed 13.2 % in 1999, 11.2% in 2005 and finally reached 8.8% in 2011. The operation test data showed a trend of decreasing of generation electricity and capacity factor during the 12 years operation time and we guessed that was caused by solar cell performance degradation and decreasing of PCS system efficiency.

• Journal of Internet Computing and Services
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• v.12 no.1
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• pp.131-139
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• 2011

The purpose of this research is to evaluate patient's satisfaction and clinician' knowledge level about pain, nausea, vomiting, and temperature management of patients after operation by develop an web-based evidence-based practice guideline about pain, nausea, vomiting, and temperature control after operation in order to apply the guideline operation patients. The collected data was analyzed through real number, average, standard deviation, t-test and repeated ANOVA by using SPSS/WIN 17.0 program. The study subjects showed a significant difference in the level of knowledge about pain, nausea/vomiting, and temperature control after operation and patient's satisfaction, before and after applying the web-based evidence-based practice guideline.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.835-842
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• 2020

This paper considers a method of reproducing abnormal and fault operation for smart monitoring of thrust bearing used in wave power generation system. In order to develop smart monitoring technology, abnormal and failure data of actual equipment are required. However, it is impossible to artificially break down the actual equipment in operation due to safety and cost. To tackle this problem, a test bed that can secure data through reproduction of a faulty operating environment should be developed. Therefore, in this study, test bed that can reproduce each situation was developed and the operation result was analysis after identifying the situation to be reproduced through the failure factor analysis of the thrust bearing.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.224-227
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• 2008

The present study performs a test of a change in a condenser pressure on two kinds of power plants having different condenser pressure-heat rate correction curve and evaluates the results. According to a result of the test, it is confirmed that a sub-critical drum type steam power plant is optimally operated at the condenser pressure of 38㎜Hga that is designed, even during winters. On the other hand, it can be found that a supercritical once through type steam power plant operated at the condenser pressure that is reduced below a design value, that is, up to 28㎜Hga during winters is advantageous in view of turbine efficiency and is operated without a problem in facility operation such as moisture erosion, turbine vibration, etc. Also, the present study compares and reviews a condenser pressure-heat rate correction curve proposed by a manufacturer and a test value. The present study proposes optimum condenser operation pressure capable of concurrently satisfying the stable operation and efficiency improvement of the power plant facility that is operating, making it possible to support an efficient operation of a power plant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5513-5521
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• 2015

There is an operational efficiency problem about wayside equipment applied to the domestic low-density branch as the equipment has been installed and operated similarly in the mainline. On-board oriented train control system, which has been developed for train safety and operation efficiency, ensures safe train operation without expensive ground control signal devices. Such system consists of on-board control system, wayside control system, and local control system. In this paper, the details of tests such as suitability test, communication test, and interface test are described by installing the on-board control system and wayside control system in field. Installation tests include checking power, voltage, cable connection, LED status, etc. Field applicability of the developed system is also verified through the dynamic operation tests with diverse scenarios, which are performed on the virtual line similar to the real environment including switch machine and level crossing gate. Dynamic operation tests were conducted for total 7 scenarios, and several tests were repeated for each scenario. The elapsed time for each operation was computed by analyzing main process log, and we could check that each operation was accomplished within several seconds. Furthermore, the developed system was verified through field test with an accredited institute, and testing certificates were issued.