• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.479-483
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• 2004

A new calculation method of expected overtopping probability of rubble mound breakwater considering real tide occurrence has been proposed. A calculation method of expected overtopping probability of rubble mound breakwater was proposed by Kweon and Suh (2003). In their calculation, the fluctuation of tidal elevation was expressed by the sinusoidal change that yields the uniform distribution of occurrence frequency. However, the realistic distribution of tidal elevation should influence on the overtopping chance. In this study, the occurrence frequency of tidal elevation obtained from the real sea is included. The tidal elevation used in this study is collected from the east coastal part of Korean peninsular. Analyzing the annual data of the tidal fluctuation measured hourly during 355 days, the distribution of occurrence frequency is formulated utilizing by the normal distribution with one peak. Among the calculation procedures of annual maximum wave height, wave height-period joint distribution, wave run-up height and occurrence frequency of tide, only the annual maximum wave height is again chosen randomly from normal distribution to consider the uncertainty. The others are treated by utilizing the distribution function or relationship itself, It is found that the inclusion of the variability of tidal elevation has great influence on the computation of the expected overtopping probability of rubble mound breakwater. The bigger standard deviation of occurrence frequency is, the lower the overtopping probability of rubble mound breakwater is.

• 한국수소및신에너지학회논문집
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• 제14권2호
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• pp.131-137
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• 2003

Backfire occurrence must be controlled for the practical use of hydrogen fueled engine. It was found from preceeding studies that crevice volume around piston rings could effect a backfire occurrence. In this study, a possible countermeasure to backfire occurrence was evaluated by using multi point ignition method around piston ring. The results showed that backfire limited equivalence ratio was increased by a little due to a enhancing effect of mixture combustion around piston crevice volume.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권7호
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• pp.2736-2754
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• 2015

Android dominates the mobile operating system market, which stimulates the rapid spread of mobile malware. It is quite challenging to detect mobile malware. System call sequence analysis is widely used to identify malware. However, the malware detection accuracy of existing approaches is not satisfactory since they do not consider correlation of system calls in the sequence. In this paper, we propose a new scheme called Artificial Neural Networks (ANNs) on Co-occurrence Matrices Droid (ANNCMDroid), using co-occurrence matrices to mine correlation of system calls. Our key observation is that correlation of system calls is significantly different between malware and benign software, which can be accurately expressed by co-occurrence matrices, and ANNs can effectively identify anomaly in the co-occurrence matrices. Thus at first we calculate co-occurrence matrices from the system call sequences and then convert them into vectors. Finally, these vectors are fed into ANN to detect malware. We demonstrate the effectiveness of ANNCMDroid by real experiments. Experimental results show that only 4 applications among 594 evaluated benign applications are falsely detected as malware, and only 18 applications among 614 evaluated malicious applications are not detected. As a result, ANNCMDroid achieved an F-Score of 0.981878, which is much higher than other methods.

• 한국수소및신에너지학회논문집
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• 제13권1호
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• pp.65-73
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• 2002

Because of low flame ion density in hydrogen-air mixture, many residual electric energy could be existed in the ignition system of hydrogen engine, If these residual energy discharged abnormally during intake stroke, it may be the cause of backfire occurrence which is serious problem in development of hydrogen fueled engine but unsolved in spite of many concerned research on it. In this study, the possibility of backfire occurrence by abnormal electric discharge and countermeasure of that were investigated by using the experimental single cylinder hydrogen fueled engine with two types of ignition system. The results show that abnormal electric discharge appeared in low load with low ion density and then results in back fire occurrence, It is also seen that countermeasure method installing larger earth resistance in high tension code is effective to control abnormal electric discharge.

• Structural Engineering and Mechanics
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• 제34권5호
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• pp.625-634
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• 2010

The objective of this paper is to apply a new proposed accuracy indicator to quantify the true and false modes for Eigensystem Realization Algorithm using output-based responses. First, a discrete mass-spring system and a simply supported continuous beam were modelled using finite element method. Then responses are simulated under random excitation. Natural Excitation Technique using only response measurements is applied to compute the impulse responses. Eigensystem Realization Algorithm is employed to identify the modal parameters on the simulated responses. A new accuracy indicator, Normalized Occurrence Number-NON, is developed to quantitatively partition the realized modes into true and false modes so that the false portions can be disregarded. Numerical simulation demonstrates that the new accuracy indicator can determine the true system modes accurately.

• Mycobiology
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• 제28권4호
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• pp.193-196
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• 2000

Thirty-eight species in addition to 2 varieties (3 unidentified) of zoosporic organisms belonging to 14 genera of Oomycetes and 3 genera of Chytridiomycetes were recovered from 50 soil samples randomly collected from different localities in the western region of Saudi Arabia. Allomyces and Dictyuchus have the highest frequency of occurrence while Achlya, Aqualinderella, Saproleginia and Phytophthora were of moderate occurrence, The remaining genera were less frequent. Seven species and two varieties were new records to Saudi Arabia, which are Achlya oblongata, Allomyces javancius var. allomorphus, Aphanomyces stellatus, Blastoccladia gracile, Dictyuchus magnusii, Olpidiopsis Saproleginia var. levis, Olpidium species, Phytophthora megasperma, and Saproleginia turfosa. Water and organic matter contents of soil samples are considered as major factors influencing the prevalence and occurrence of zoosporic organisms.

• 한국응용곤충학회지
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• 제31권1호
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• pp.69-78
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• 1992

벼신품종의 광범위한 재배는 벼해충상의 변화에 영향을 주었을 것으로 사료된다. 끝동매미충과 애멸구의 발생은 통일계 신품종의 재배면적이 많이 증가하기 시작한 1976년 이후 급격히 감소하는 경향을 보여주었다. 한편, 최근 23년간 자료를 분석한 결과 전체적인 벼해충이 급격히 감소하였으나 이화명나방은 최근에 다시 증가하는 추세를 보이고 있다. 이러한 경향은 신품종재배와 과다한 시비 및 살충제의 대량살포와 깊은 관계가 있는 것으로 분석되었다.

• Animal cells and systems
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• 제2권4호
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• pp.507-511
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• 1998

Fingerprints of 100 New Zealand-Samoan males and 93 females have been analyzed. Whorls are more numerous in fingerprint females (65.6%) than in males (55.6%). The index of pattern intensity displays a higher value in females (16.49) than in males (15.48). The bimanual differences both in males and females are not statistically significant for the occurrence of patterns on the digits of the right and left hands. Also the difference between both sexes for the occurrence of patterns is not statistically significant. Incidences of actual symmetry on homologous digits represented 78.2% in males and 85.8% in females. The mean total ridge counts showed $175.7{\pm}54.6$ ($M{\pm}SD$) in males and $171.6\{pm}49.8$ ($M{\pm}SD$) in females, respectively. Conclusively, this study shows that the New Zealand-Samoans are closely related to the Mongoloids in quantitative dermatoglyphics.

• 한국토양비료학회지
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• 제50권4호
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• pp.215-225
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• 2017

Kiwifruit is prone to damage by frost in the harvest season and the occurrence of postharvest diseases. Accordingly, new cultivars overcoming these disadvantages have been developed. Compared to existing cultivars, studies on diseases in new cultivars are very limited. Thus, goal of this study was investigation of fungal infection occurrences in new cultivars. Kiwifruit was harvested in 2014 and 2015 year, respectively. In both years, cvs. Goldone and Redvita showed more resistance against fungal infection but cv. Gamrok was more sensitive compared with cv. Hayward. Major fungi were identified as Botryosphaeria dothidea, Phomopsis sp., Alternaria alternata and Nigrospora sp. Firmness and soluble solids content were also influenced by the occurrences. This study's findings are important for providing practical information on new cultivars in the kiwifruit industry.

• 응용통계연구
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• 제21권4호
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• pp.649-658
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• 2008

외식산업의 발달과 함께 학교와 기업 등의 단체 급식이 증가하고 있는 오늘날, 관련분야에서는 식중독 예방에 대해 많은 관심을 갖고 연구하고 있다. 우리나라에서는 온도에 따른 세균의 증식속도를 이용하여 식중독지수를 개발하여 식중독 위험에 대한 정보를 제공하고 있는데 그 정보가 식중독 발생상황과는 차이가 있음이 지적되고 있다. 본 연구에서는 최근 3년간($2004{\sim}2006$년)의 일별 식중독 발생과 기상자료를 이용하여 일 최고기온, 습도, 월효과를 설명변수로 하고, 식중독 발생건수를 반응변수로 하는 로그선형모형(Log Linear Model)을 이용하여 식중독 발생의 위험을 예보할 수 있는 사고발생지수를 개발하였다. 개발된 지수와 기존지수를 비교한 결과 개발된 지수가 식중독 발생 상황을 반영함에 있어서 더 나은 설명력이 있음이 나타났다.