• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.47-55
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• 2009

In recent network intrusion detection systems, regular expressions are used to represent malicious packets. In order to process incoming packets through high speed networks in real time, we should perform hardware-based pattern matching using the configurable device such as FPGAs. However, operating speed of FPGAs is slower than giga-bit speed network and so, multi-byte processing per clock cycle may be needed. In this paper, we propose a hardware architecture of multi-byte based regular expression pattern matching and implement the pattern matching circuit generator. The throughput improvements in four-byte based pattern matching circuit synthesized in FPGA for several Snort rules are $2.62{\sim}3.4$ times.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.23-28
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• 2013

This study focuses on finding ways to derive train's optimal ECO driving pattern, which can improve the ride quality and reduce driving energy consumption with keeping the time interval between the stations. As research method, we compared difference of currently operating train's ATO and MCS driving patterns, and concentrated upon the things need to consider in simulation in order to improve the existing pattern of ATO driving pattern's issues with securing the train operation safety. Determining driving pattern minimizing energy consumption by controlling powering within speed limit and controlling switching to coasting at appropriate point considering the track conditions for each section, and determining braking control starting time considering ride comfort and precise stopping is considered to be most important.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.751-753
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• 2001

휴대전화는 기존의 음성통신 기기에서 데이터 통신 기기로 확대 발전되고 있으며 지원되는 데이터 통신 대역폭도 점차 고속화되어 가고 있다. 최근에는 이러한 대역폭을 이용한 멀티미디어 서비스가 시작되고 있으나, 무선망에 대한 정확한 분석 없이 기존 유선망의 특성에 기반하여 서비스를 제공하고 있다. 본 논문에서는 효과적인 멀티미디어 데이터 서비스를 위해, CDMA-2000무선망을 대역폭, 패킷 지연 시간 및 에러율 측면에서 측정하고 그 결과를 분석한다.

• Journal of Applied Reliability
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• v.2 no.1
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• pp.1-14
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• 2002

High temperature operating test, temperature humidity test and temperature cycling were performed at various test levels for solid aluminum electrolyte capacitors made by domestic manufacturing company and foreign advanced manufacturing company. It was found that main failure mode of solid aluminum electrolyte capacitors was the decrease of their capacitances. The decrease of their capacitances has the same pattern in these tests. Test result for comparison of characteristics between domestic products and foreign advanced products shows that domestic products have the shorter lifetime and their capacitances decrease more rapidly in high temperature operating test and temperature humidity test. Also in these tests, accelerated tests for high temperature operating test and temperature humidity test were developed.

• Asian Journal of Innovation and Policy
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• v.10 no.3
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• pp.330-354
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• 2021

To know the long-term growth patterns and determinants of successful startups, 15-year (2006-2020) panel data of 252 companies that had a growth rate of over 20% every year in the last three years were used. In the first analysis, statistics on the period required to designate a gazelle company or listed on the stock market were examined. In addition, five long-term growth patterns were presented. In the panel analysis, the R&D intensity, operating profit ratio, size, and age of the company were pointed out as determinants of growth. The operating profit margin and R&D intensity have a positive effect on growth. Gibrat's law was not supported, but an inverted U-shape was observed. Jovanovic's law was confirmed. Although many studies tend not to point to profitability as a determinant of long-term growth, this is an important long-term growth factor of a company. The operating profit ratio was used in this study.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.2
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• pp.17-26
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• 2016

Objectives : We presented the results of reliability study in advance, and analyzed agreement between Korean medicine doctors(KMDs)' diagnosis and cold-heat pattern identification questionnaire(CHPI)'s diagnosis. Methods : This survey was conducted from May 16 to 17, 2015. The subjects were 93 adults living in rural society. Diagnosis of CHPI was performed by 2 KMDs who have clinical experience more than 5 years. The KMDs' diagnosis was set as a reference index, and then we compare 23 items(cold pattern 11 items and heat pattern 12 items) of CHPI questionnaire and 15 items(cold pattern 8 items and heat pattern 7 items) that were brief form of it. We had cut-off value by standard of KMDs' diagnosis using receiver operating characteristic-curve(ROC-curve), with which we calculated agreement including kappa value. Correlation analysis between CHPI evaluation score by KMDs and by the questionnaire was fulfilled as well. Results : Agreement about 11 and 8 cold pattern items showed 87.1% together, and the value of kappa each recorded 0.742 and 0.741. Agreement about 12 and 7 heat pattern items suggested 81.7% and 78.5%, and the value of kappa showed 0.634 and 0.570. Correlation coefficients were 0.803 of 11 items and 0.761 of 8 items about cold pattern. In addition, correlation coefficients were 0.789 of 12 items and 0.767 of 7 items about heat pattern. The significant probability (p-value) was under 0.001. Conclusions : We have developed CHPI questionnaire involving reliability and agreement based on usual symptoms, and hope additional complements so that Korean medicine diagnostics and Korean preventive medicine would be improved.

• Journal of information and communication convergence engineering
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• v.5 no.1
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• pp.42-44
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• 2007

The a-Si:H TFTs decreasing parasitic capacitance of source-drain is fabricated on glass. The structure of a-Si:H TFTs is inverted staggered. The gate electrode is formed by patterning with length of $8{\mu}m{\sim}16{\mu}m$ and width of $80{\sim}200{\mu}m$ after depositing with gate electrode (Cr) $1500{\AA}$ under coming 7059 glass substrate. We have fabricated a-SiN:H, conductor, etch-stopper and photoresistor on gate electrode in sequence, respectively. The thickness of these, thin films is formed with a-SiN:H ($2000{\mu}m$), a-Si:H($2000{\mu}m$) and $n^+a-Si:H$ ($500{\mu}m$). We have deposited $n^+a-Si:H$, NPR(Negative Photo Resister) layer after forming pattern of Cr gate electrode by etch-stopper pattern. The NPR layer by inverting pattern of upper gate electrode is patterned and the $n^+a-Si:H$ layer is etched by the NPR pattern. The NPR layer is removed. After Cr layer is deposited and patterned, the source-drain electrode is formed. The a-Si:H TFTs decreasing parasitic capacitance of source-drain show drain current of $8{\mu}A$ at 20 gate voltages, $I_{on}/I_{off}$ ratio of ${\sim}10^8$ and $V_{th}$ of 4 volts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1391-1394
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• 2007

In order for Hypoid gear development. Gears are required to sustain heavy loads or on applications where the gear box is made or a material with a different coefficient of thermal expansion form that or the gears and shafts, it is desirable to make a deflection and contact check under load. The deflection test is performed in the actual gear mounting using completely processed gear. This test should cover the full operating range of gear loads from no load to peak load. Under peak load the contact pattern should extend to the tooth boundaries without showing a concentration of the contact pattern at any point on the tooth surface.

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.66-75
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• 1998

The computer simulation model was used to forecast the concentrations of COD$_{cr}$, NH$_{4}$$^{+}$-N and NO$_{3}$$^{-}$-N in each reactors. In the biological wastewater treatment system, the computer simulation model was used to observe the behavior of pollutants especially. In this research, effect of SRT, feeding pattern and recirculation rate on UCT(University of Cape Town) process was evaluated by computer simulation model. T-N removal was affected to the SRT. SRT for effective T-N removal was 15 days or longer. Feeding pattern in UCT process was affected to the T-N removal. Feeding pattern which 100% loading to the first reactor was most effective for T-N removal. The effect of recirculation rate was clear for T-N removal. The recirculation from anoxic reactor to anaerobic reactor was not need but the recirculation from oxic reactor to anoxic reactor was need. In aspect of nitrogen removal efficiency, A/O process was higher than UCT process.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.6
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• pp.765-771
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• 1998

An artificial neural network(NN) technique is developed for hardware redundant sensor validation. Since the measurement space is a continuous space with many operating regions, it is difficult to train a NN to correctly detect failure in an accurate measurement system. A conventional backpropagation NN is modified to include an additional preprocessing layer that extracts classification features from scalar measurements. This feature extraction means transform the measurement space to parity space. The NN is independent of the state variable being measured, the instrument range, and the signal tolerance. This NN resembles the parity space approach to signal validation, except that analytical parity equations are unneeded and the NN pattern recognition capability is utilized for decision making.