• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1499-1502
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• 2003

This paper describes the result of carbody and vibration test for freight car. The purpose of the test is to evaluate an safety which carbody structure shall be considered fully sufficient rigidity so as to load a freight car under maximum load and operating condition on line track. The test carbody is constructed by RS korea co., LTD. in accordance with KNR specfication. The test cases of the carbody is tested the vertical load and compressive load to verify the strength and stillness. The vibration test is tested for analysis and evaluation of vibration, to allow for the fact that mechanical vibration in railway vehicles have specific characteristics.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.1
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• pp.37-43
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• 2005

Plant pipe has a fatigue life which is induced by repeated stress come from the variation of temperature and pressure. To avoid the fatigue crack of plant pipe which is produced by long term repeated stress, plant operator has to limit the mont of operating transient. This paper introduced the study result about discrimination methodology of plant transient by using the fuzzy pattern recognition. As result of applying the fuzzy pattern recognition to actual plant operation data, it is confirmed that fuzzy pattern recognition methodology can be useful for the comparison of similarity for the transients of similar output but has different time pattern.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4856-4872
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• 2018

The mobile internet has grown ubiquitous across the globe with the widespread use of smart devices. However, the designs of modern mobile operating systems and their applications limit content retrieval with mobile applications. The mobile internet is not as accessible as the traditional web, having more man-made restrictions and lacking a unified approach for crawling and content retrieval. In this study, we propose an automatic and scalable mobile application content crawler, which can recognize the interaction paths of mobile applications, representing them as interaction graphs and automatically collecting content according to the graphs in a parallel manner. The crawler was verified by retrieving content from 50 non-game applications from the Google Play Store using the Android platform. The experiment showed the efficiency and scalability potential of our crawler for large-scale mobile internet content retrieval.

• Advances in nano research
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• v.1 no.1
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• pp.13-27
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• 2013

Carbon nanotube characterized by additional inductive effect as compared with the traditional conductors like copper wires of the same size. Consequently, carbon nanotubes have high characteristic impedance and slow wave propagation in comparison with traditional conductors. Due to these characteristics, carbon nanotubes can be used as antenna. In view of this, we describe and review the present research progress on carbon nanotube antennas. We present different analysis models and results which are developed to investigate the characteristics of CNT antennas. Then we conclude by summarizing the characteristics of CNT antennas and specifying the operating frequency limit.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.9
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• pp.98-105
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• 1995

Recent microwave IC's reach to the extent of high operating frequencies at which bonding wires limit their performance as dominant parasitic components. Double bonding wires separated by an internal angle have been firstly characterized using the Method of Moments with the incorporation of the ohmic resistance calculated by the phenomenological loss equivalence method. For a 30$^{\circ}$ internal angle, the calculated total reactance is 45% less than that of a single bonding wire due to the negative mutual coupling effect. The radiation effect has been observed decreasing the mutual inductance, whereas for parallel bonding wires it greatly increases the mutual inductance. This calculation results can be widely used for designing and packaging of high frequency and high density MMIC's and OEIC's.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.09a
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• pp.35-42
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• 2002

Frequency responses for most of the local seismic sensors in Korea have been roughly checked by mutual comparison of Fourier spectra of seismic records from accelerometer and seismometer, both of which are installed at the same location. Especially, because the frequency content of the seismic energy is usually above 1 Hz for local earthquakes, the reliability of low frequency response could have not been evaluated. Fortunately a recent large earthquake, Ms=7.2 on 02/06/29 containing dominant low frequency energy makes it possible to check the low frequency response of the seismic sensors, especially EpiSensor and JC-V100. Considering two types of sensor pairs, (STS-2 and EpiSensor, JC-V100 and EpiSensor), the low frequency response of EpiSensor is confirmed first by comparison with STS-2 which has proved low frequency response. Second, reliable low frequency limit of instrumentally corrected seismic data from JC-V100 data is estimated to be about 0.03 Hz by comparison with EpiSensor data.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.34-41
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• 2005

Construction of the Shinkansen was planned on the basis of a traffic volume determined by the Trunk Line Investigation Committee set up within JNR in 1957. Passenger and freight traffic along the vitally important Tokaido Main Line had been steadily increasing, passenger traffic reaching $24\%$ and freight $23\%$ of the total domestic traffic. Train frequency was expected to reach the upper limit in the 1960s. Estimated traffic volume was 13,000 million passenger-km for the opening year 1964 and 20,000 million for 1975. Although the traffic did not reach the estimed figure during 1975 reached about twice the estimated figure for the Tokyo-Shinoska Section. The amazing growth of the national economy was undoubtedly responsible for this.

• Journal of Technology Innovation
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• v.14 no.2
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• pp.117-141
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• 2006

The paper describes the status and context of the Chinese Open Source Software (OSS) industry and ecosystem based on the analysis of the components of the China OSS Promotion Union. The analysis involves comparisons of several main Chinese developers of Linux operating system and makers of open source counterpart of the popular Microsoft Office package as well as several main Chinese OSS communities. Comparisons concern the technological and business aspect. The findings reveal peculiarities of the divergence of innovative activities of Chinese companies, as well as indicate that the strong government support may at the same time limit the technology selection under rigid competition, especially as foreign open source companies are found to be more focused on hobbyist developers and are able to maintain larger independent communities. Implications of the paper include the need to coordinate global development efforts and adjust science & technology policies in order to stimulate both the development and the diffusion of open source among Chinese companies and individual hobbyists.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.195-198
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• 2004

This study applied EK method to remediate contaminated soil by heavy metal(Pb), tried to increase the efficiency of remediation using zeolite as enhanced EK remediation method to overcome the limit of traditional EK remediation method. Adsorption tests on Pb were conducted to apply the EK extraction and test conditions which contained the electrode reversal, operating time were established. After tests, lead-ions were transported into the specific position of zeolite by EK phenomena, then the immobilization of lead-ions at zeolite was developed. Based on these tests, the efficiency of remediation is different with its test conditions. In addition, the efficiency of remediation was improved dramatically by adding zeolite without electrode reversal and satisfied TCLP regulation of EPA in USA through the whole sample range. Finally, absorption and immobilization capacity of zeolite were proved its excellence and confirmed the possibility of application as enhanced EK remediation method.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.113-114
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• 2008

For the supported high-technology, it is in need of estimation about power quality and reasonable price through machinism. The power system made much of precision digital industrial damage under sag. This study suggested electric machine under effects of power quality in the theory and test. A electric machine was simulated and experimented about sag. The test system made up IPC as voltage sag device. The test machine was magnetic contactor and PLC. The result, electric machines appeared to influence sag with CBEMA curve. It was make possible analysis of power system about a fault. This study was expected to method that investment and development of equipment on power market in the future.