• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.197-204
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• 1997

Torques on each joint, the compression on L5/S1 disc, the force on hand of a rider are estimated using a static biomechnic model. Forces that the rider applies to the pedals, saddle and handle during starting and speeding are estimated using static mechanics. Physical stress is considered accroding to handle height and horizontal distance between handle and pedal. When handle height is higher in normal speeding, the force on handle and sum of torques on each joint decreases.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.107-113
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• 2006

Speeding is one of major causes of frequent and severe traffic accidents in school zones. In this paper, the long-term effectiveness of speed monitoring displays (SMD) on speed variability was investigated through a field study in a school zone environment. The performance difference was discussed with several dependent variables including average speed, 85th percentile speed, and distribution of speed. Study results showed that the speed of vehicles began to reduce where the driver recognized the presence of an SMD, and about 12.4 percent (5.8km/h) of average speed was reduced at the SMD location. This speed reduction was observed throughout the day regardless of time of day. Statistical tests showed that the speed difference was statistically significant. In addition, analysis results of speed distribution showed that the number of speeding vehicle was greatly reduced after the SMD was installed, and 85th percentile speed also decreased from 54.3km1h to 45.0km/h. Therefore, it was concluded that the application of SMD produced a positive impact on the driver's behavior for a long period of times.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.593-596
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• 2018

The speed of vehicles has remained a significant factor that influences the severity of accidents and traffic accident rate in many parts of the world including South Korea. This behavior where drivers drive at speeds which exceed a posted safe threshold is known as 'speeding'. Over the past twenty years, the Korean National Police Agency (NPA) has become aware of an increased frequency of drivers who are speeding. Therefore, fixed-type ASE systems [1] have been installed on hazardous road sections of many highways. These system monitor vehicle speeds using a camera. However, the use of ASE systems has changed the behavior of the drivers. Specifically, drivers reduce speed or avoid the route where the cameras are mounted. It is not practical to install cameras at every possible location. Therefore, it is challenging to thoroughly explore the location where speeding occurs. In view of these problems, the author of this paper designed and implemented a prototype visualization system in which point and color are used to show vehicle location and associated over-speed information. All of this information was used to create a comprehensive visualization application to show information about vehicle driving. In this paper, we present an approach detecting vehicles moving at speeds which exceed a threshold and visualizing the points those violations occur on a map. This was done using vehicle trajectory data collected in Daegu city. We propose steps for exploring the data collected from those sensors. The resulting mapping has two layers. The first layer contains the dynamic vehicle trajectory data. The second underlying layer contains the static road networks. This allows comparing the speed of vehicles on roads with the known maximum safe speed of those roads, and presents the results with a visualization tool. We also compared data about people who drive over threshold safe speeds on each road on days and weekends based on vehicle trajectories. Finally, our study suggests improved times and locations where law enforcement should use monitoring with speed cameras, and where they should be stricter with traffic law enforcement. We learned that people will drive over the speed limit at midnight more than 1.9 times as often when compared with rush hour traffic at 8 o'clock in the morning, and 4.5 times as often when compared with traffic at 7 o'clock in the evening. Our study can benefit the government by helping them select better locations for installation of speed cameras. This would ultimately reduce police labor in traffic speed enforcement, and also has the potential to improve traffic safety in Daegu city.

• 한국도로학회:학술대회논문집
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• 2009.11a
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• pp.271-277
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• 2009

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.11
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• pp.2235-2253
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• 2011

Digital document file such as Adobe Acrobat or MS-Office is encrypted by its own ciphering algorithm with a user password. When this password is not known to a user or a forensic inspector, it is necessary to recover the password to open the encrypted file. Password cracking by brute-force search is a perfect approach to discover the password but a time consuming process. This paper presents a new method of speeding up password recovery on Graphic Processing Unit (GPU) using a Compute Unified Device Architecture (CUDA). PDF files are chosen as a password cracking target, and the Abode Acrobat password recovery algorithm is examined. Experimental results show that the proposed method gives high performance at low cost, with a cluster of GPU nodes significantly speeding up the password recovery by exploiting a number of computing nodes. Password cracking performance is increased linearly in proportion to the number of computing nodes and GPUs.

• International Journal of Railway
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• v.6 no.2
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• pp.78-84
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• 2013

This paper is about the first experiment in Korea that was conducted on speeding increase up with rail speeds at 430km/h at high speed railway of designed 350km/h. and analysis data collected on vibration accelerations of roadbed. There are barely references on roadbed behavior measurement with rail speeds more than 350 km/h in Korea as it has never been conducted the experiment on it. So the experiments were confirmed the reliability through crosschecking the figures/values from respective sensors and measuring devices after measuring EMS and ICP types. Based on the study, values of vibration acceleration were less than 12% compared with the ones that conducted while speeding up of HEMU-430X. Also, figures of HSB for concrete bed tracks were 52% against the standard. According to the results, all the performance evaluation of vibration acceleration for roadbeds in transition zones is under the standard.

• International Journal of Railway
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• v.3 no.3
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• pp.90-94
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• 2010

In this paper, driving functions of the Korea High-speed Trains were decomposed based on systems engineering architecture. In order to analyze the driving function, various systems engineering tools and methods were used. Moreover, interfaces of decomposed driving functions were analyzed to figure out purposes of the driving functions. Through activity modeling of driving function of the Korea High-Speed Trains, main functions were derived when starting, speeding and stopping. When the high speed train is speeding, pre-departure checks and wheel slide prevention are essential driving activities for the safety and when the high speed train runs high speed, maintaining driving stability by monitoring bogie hunting and monitoring drivers' safe operation by vigilance systems is important. Furthermore, when the train is braking, the driver should checks brake and suspensions as safety actions.

• Proceedings of the KIEE Conference
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• 2002.06a
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• pp.166-171
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• 2002

We are in transitional period of welding technique, which has changed from the stage of quantity and quality to the stage of future technique, imported and introduced from many advanced countries. Therefore, many researches and studies for development on high speeding and making welding machines with high effectiveness has been doing vigorously. In this dissertation, I have studied on a pulsed MAG welding machine, with which welding of thin plates may perform high speeding and effecting. First, I produced a phase shifted full bridge DC-DC convert, which is the type of reduced conduction loss and the power supply for welding machine. And then, I found out an output waveform control algorithm about one pulsed one droplet and short waveform control for thin plates with high speed by deriving the circuit model utilizing the circuit averaged method for full bridge converter.

• International Journal of Highway Engineering
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• v.16 no.6
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• pp.149-158
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• 2014

PURPOSES : The bridge section of the expressway has a worse driving environment than the general section. However, traffic safety countermeasures are focused only on the bridge section. Traffic safety countermeasures on the section before entry to the bridge and the section after exit from the bridge are applied only when the bridge has a long-span section. Accordingly, this study will verify the necessity of extending the application of traffic safety countermeasures to areas that are affected by the bridge. METHODS : This study determines the areas that are affected by the bridge as well as the areas that are affected by locations with frequent traffic accidents and suggests the risk factors by affected areas through canonical discriminant analysis. For the analysis, traffic accident data for 3 years, which occurred on bridge sections in six major expressway lines, were used. RESULTS : The numbers of traffic accidents were 469 before the bridge, 281 on the bridge, and 468 after the bridge. The variables that have impact on the seriousness of accidents are as follows: speeding, excess manipulation of the steering wheel, and failure to secure safety distance for accidents that occurred before the bridge section; speeding, excess manipulation of the steering wheel, and dozing off for accidents that occurred on the bridge; and speeding and failure to secure safety distance for accidents that occurred after the bridge section. CONCLUSIONS : Areas affected by the bridge show higher accident rates than the bridge section; therefore, imposing traffic safety countermeasures on the integrated section of the bridge and the affected areas is required. It is believed that the results suggested in this study could be effectively used in the prevention of traffic accidents by imposing custom-made safety countermeasures for each section.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.95-105
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• 2007

Speeding and drunken driving make drivers fail to detect hazards and cope with various driving situations. These behaviors also raise the possibility of being involved in traffic accidents and tend to increase the number of fatalities. The authors compared the driving behavior determinants of a rockless drivers group, consisting of individuals who have committed traffic accidents or offended regulations through drunken driving, with a normal drivers group. In the results, the reckless drivers group showed high scores of 'speeding' and 'drunken driving', and they also stated that they had more experiences of speeding, drunken driving and traffic accidents. In the path analysis study, it was found that the impacts of the rockless drivers group's 'risk sensitivity' and 'situational adaptability' on traffic accidents were stronger than those of normal drivers. This means 'risk sensitivity' and 'situational adaptability' can explain the origins of traffic accidents better in the reckless drivers group than accidents of the normal drivers group.