• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.1
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• pp.113-119
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• 2014

Recently, R.O.K. Navy is increasing re-usability of design data and application of M&S(Modeling and Simulation) through the establishment of collaborative product development environment focused on Naval Ship Product Model(NSPM). As a result, the reliability of the result of design is getting better, and furthermore, a study to improve quality of construction through simulation of production/operation is in progress. Accordingly, the database construction of design data and the DB(Database) quality become important, but there was not research related to those or it was just initial state. This paper conducted research about system of the quality verification process of shape elements which compose NSPM based on the quality verification guideline of NSPM as the result of the precedent study. The hull surface was limited as verification object. The study to verify two things that application of basic drawing by the cad model of hull surface, and whether there is error in the geometric quality of cad model was progressed. To achieve this goal, the verification criteria and algorithm were defined and the prototype system which is based on was developed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.4
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• pp.55-62
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• 2012

In this study, it was observed through the ability of performing secondary tasks and baseline fetal heart rate how the supply of lavender, peppermint and highly concentrated oxygen (40%) affected distraction due to the performance of secondary tasks in the driving environment. Twelve male university students conducted secondary tasks while driving in the environments (6 in total) mixed and designed with oxygen concentration (21%, 40%) and the condition of odors (Normal, Lavender, Peppermint). The test was proceeded in order of stable state (5mins), driving (5mins), and secondary tasks (1min), and by extracting ECG data from every section by 30secs, the mean value of baseline fetal heart rate was calculated. As a result of analysis, in the ability of performing secondary tasks, a percentage of correct answers showed no difference in oxygen concentration and the condition of odors (p > 0.05). In performance completion time, a percentage of correct answers decreased showing a statistically significant difference in the condition of odors compared with the condition where odors were not provided (p < 0.05). As for baseline fetal heart rate, in the comparison between sections, while performing secondary tasks, it increased showing a significant difference compared with stable state and driving state (p < 0.05). The effect of interaction was observed in oxygen concentration and the condition of odors. When odors were not provided, baseline fetal heart rate decreased in 40% oxygen concentration compared with 21% oxygen concentration (p < 0.05), however, when peppermint was provided, it increased in 40% oxygen concentration compared with 21% oxygen concentration (p < 0.05). In conclusion, the fact that the condition of odors increased the ability of calculation, and when only the highly concentrated oxygen was provided, parasympathetic nerve system was activated, however, when highly concentrated oxygen was provided with peppermint at the same time, sympathetic nervous system (sns) was activated, which had a negative effect on the autonomic nervous system was drawn.

• The Journal of the Acoustical Society of Korea
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• v.21 no.5
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• pp.471-477
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• 2002

Recently, lip-reading has been studied actively as an auxiliary method of automatic speech recognition(ASR) in noisy environments. However, almost of research results were obtained based on the database constructed in indoor condition. So, we dont know how developed lip-reading algorithms are robust to dynamic variation of image. Currently we have developed a lip-reading system based on image-transform based algorithm. This system recognize 22 words and this word recognizer achieves word recognition of up to 53.54%. In this paper we present how stable the lip-reading system is in environmental variance and what the main variant factors are about dropping off in word-recognition performance. For studying lip-reading robustness we consider spatial valiance (translation, rotation, scaling) and illumination variance. Two kinds of test data are used. One Is the simulated lip image database and the other is real dynamic database captured in car environment. As a result of our experiment, we show that the spatial variance is one of degradations factors of lip reading performance. But the most important factor of degradation is not the spatial variance. The illumination variances make severe reduction of recognition rates as much as 70%. In conclusion, robust lip reading algorithms against illumination variances should be developed for using lip reading as a complementary method of ASR.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.55-63
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• 2020

The IoT technology is a field that applies and converges the technologies in the existing industrial environment, instead of new technologies. The IoT technology is releasing various application services converged with other industries such as smart home, healthcare, construction, and automobile, and it is also possible to secure the work efficiency and convenience of users of IoT-based technologies. However, the security threats occurring in the IoT-based technology environment are succeeding to the vulnerability of the existing wireless network environment. And the occurrence of new and variant attacks in the combination with the ICT convergence environment, is causing damages. Thus, in the IoT technology-based environment, it would be necessary to have researches on the safe transmission of messages in the communication environment between user and device, and device and device. This thesis aims to design a safe communication protocol in the IoT-based technology environment. Regarding the suggested communication protocol, this thesis performed the safety analysis on the attack techniques occurring in the IoT technology-based environment. And through the performance evaluation of the existing PKI-based certificate issuance system and the suggested communication protocol, this thesis verified the high efficiency(about 23%) of communication procedure. Also, this thesis verified the reduced figure(about 65%) of the issued quantity of certificate compared to the existing issuance system and the certificate management technique.

• Journal of Navigation and Port Research
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• v.27 no.1
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• pp.41-48
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• 2003

The most great GPS is working on CNS(Car navigation System) and Personal terminal, but ocean has not been. First studied GPS is sailing to ship but We have been connivance that The ship is not need detail navigation. Lately, harbor facilities and transportation service in harbors are complication. We have need accurate ship navigation system. In this paper, author developed algorithms of ellipsoid conversion between WGS84 and BESSEL and develope algorithms of map projection between ellipsoid coordinate system, and plane cartesian system. Author used 3-parameter in covering ellipsoids and used TM and UTM projection in converting between ellipsoid and plane cartesian coordinate. And author analyzed errors through static surveying and dynamic surveying of GPS for proving accuracy of GPS sensor, Furthermore author analyzed deflection error of received position. Finally author developed real time ship navigation system using cheep GPS sensor.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.1C
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• pp.44-53
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• 2005

In this paper, a improved moving object detection algorithm for stable performance of surveillance system in case of iterative moving in limited area and rapidly illuminance change in background scene is proposed. The proposed algorithm is that background scenes are sampled for initializing background image then the sampled fames are divided by block and sum of graylevel value for each block pixel was calculated, respectively. The initialization of background image is that background frame is respectively reconstructed with selecting only the maximum graylevel value and the minimum graylevel value of blocks located at same position between adjacent frames, then reference images of background are set by the reconstructed background images. Moving object detecting is that the current image frame is divided by block then sum of graylevel value for each block pixel is calculated. If the calculated value is out of graylevel range of the initialized two reference images, it is decided with moving objects block, otherwise it is decided background. The evaluated results is that the error rate of the proposed method is less than the error rate of the existing methods from $0.01{\%}$ to $20.33{\%}$ and the detection rate of the proposed method is better than the existing methods from $0.17{\%}\;to\;22.83{\%}$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.1
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• pp.108-113
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• 2010

The purpose of this study was to investigate the differences of driving performance and physiological responses between young male and female drivers for unexpected situation using a graphic vehicle simulator. The participants included 20 college graduates; 23 males aged $24.3\;{\pm}\;1.4$ with $2.3\;{\pm}\;1.5$ years of driving experiences and 23 females aged $23.2\;{\pm}\;2.1$ with $2.2\;{\pm}\;1.7$ years of driving experience. The participants were instructed to drive the vehicle simulator which was programed unexpected situation for two minutes. The physiological measurements used were autonomic responses of electrocardiogram (ECG) and skin conductance response (SCR), and the driving performance measurements used were the reaction time of break and the rate of collision for unexpected situation. Results showed that there were no significant differences between male and female drivers in the reaction time of break and the rate of collision for unexpected situation. Averaged R-R interval decreased and LF IHF and SCL amplitude increased for unexpected situation. There were no significant differences between male and female in the averaged R-R interval and LF/HF for unexpected situation. On the other hand, SCL amplitude of female was higher than male. Rising time to maximum SCL amplitude of female was longer than male.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.85-97
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• 2009

Continuous increase of traffic demand has caused confirmed congestion, fuel consumption, emission, safety, etc. as serious social problems at the present time. The Smart Highway Project has been conducted by the supervision of Ministry of Land, Transport and Maritime Affaire to solve such problems since 2007. The Smart Highway Project includes LDWS (Lane Departure Warning System), a system to prevent broadside collisions and accidents, as a sub-technology of road-vehicle associating technologies. This system warns drivers when their vehicle deviates from the lane where they are traveling at high-speed on the highway. In this paper, the LDWS was evaluated using CBA to analyze the socio-economic consequences. Estimated benefits include reduction of accidents and convenience of drivers. In addition, the economics according to the distribution rate is various when it comes to Lane Departure Warning Technology, the economics of both cases - positive scenario and negative scenario, which was analyzed. As a result, the Benefit-Cost ratio(B/C) of negative scenario showed 0.97 in 2020 and 1.36 in 2030 while B/C ratio of the positive scenario showed 1.04 in 2020 and 1.59 in 2030, which indicated that the higher distribution rate is, the higher the economics generates. Therefore, it is judged that the introduction of Lane Departure Warning Technology will result in high economics.

• Journal of Auto-vehicle Safety Association
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• v.7 no.3
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• pp.7-13
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• 2015

Occupant protection performance in frontal crashes has been developed and assessed for mainly front seat occupants over many years, and in recent years protection of rear seat occupants has also been extensively discussed. Unlike the front seats, the rear seats are often occupied by children seated in rear-facing or forward - facing child restraint systems, or booster seats. In the ENCAP, child occupant protection assessments using 18-month-old(P1.5) and 3-year-old(P3) test dummies in the rear seat have already been changed to new type of 18-month-old (Q1.5)and 3-year-old(Q3) test dummies. In addition, ENCAP are scheduled with the development and introduction of test dummies of 6-year-old (Q6) and 10.5-year-old children(Q10) starting 2016. In KNCAP, Q6 and Q10 child dummies will be introduced in 2017 as well. Automobile manufacturers need to develop safety performance for new child dummies closely. In this paper, we focused on Q6 and Q10 child dummies sitting in child restraint system. Offset frontal crash tests were conducted using two types of test dummies, Q6 and Q10 child dummies, positioned in the rear seat. Q6 and Q10 were used to compare dummy kinematics in rear seating positions between Q6 behind the driver's seat and Q10 behind the front passenger's seat. The full vehicle sled test results of both dummies were conducted with different restraint systems. It showed that several injury and image data was collected as the result of the full vehicle sled test. Based on the results of these investigations, this paper describes which factor is most important and combination is the best performance when evaluating rear seat occupant protection for Q6 and Q10 child dummies.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.281-290
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• 2018

As the internal combustion engine vehicles of high fuel efficiency and low emission are demanded, it becomes important to procure technologies for improving low-temperature performance of automotive catalyst systems. In this study, we showed that the combustion rate of diesel particulate matter is greatly enhanced at low temperature by applying fuel-borne catalyst and perovskite catalyst concurrently. It was tried to examine the correlation between elemental composition of perovskite catalyst and combustion activity of mixed catalyst system. To achieve this goal, we applied temperature-programmed oxidation technique in testing the combustion behavior of perovskite-mixed particulate matter bed which contained the element of fuel-borne catalyst or not. We tried to explain the synergetic action of two catalyst components by comparing the trends of concentrations of carbon dioxide and nitrogen oxide in temperature-programmed oxidation results.