• Proceedings of the ESK Conference
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• 2004.10a
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• pp.48-48
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• 2004

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.2
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• pp.585-593
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• 1996

According to the considerable increase of the length of belt conveyors, the dynamic analysis of systme becomes necessary to consider the variation of tensions and transient motion of components during starting and stopping of conveyor. The mathematical model of system is derived using the lumped parameter method. The input driving force is represented with two functions of time and pulley speed to count the characteristics of motor and fluid coupling. An example system was studied with 14 km in the distance of carrying. At head, it has two drivers and one gravity take-up and at tail ond driver and one power winch take-up. In the example, the transient tensions and responses, calculated using two cases of driving force, are mutually compared in starting mode. Also, the position of maximum tension and the braking force of take-up are obtained in stopping mode.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3_1spc
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• pp.607-614
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• 2013

This paper proposes a robot driving system and sensor implementation for use with an education robot. This robot has multiple functions and was designed so that children could use it with interest and ease. The robot recognizes the location of a user and follows that user at a specific distance when the robot and user communicate with each other. In this work, the robot was designed and manufactured to evaluate its performance. In addition, an embedded board was installed with the purpose of communicating with a smart phone, and a camera mounted on the robot allowed it to monitor the environment. To allow the robot to follow a moving user, a set of sensors combined with an RF module and ultrasonic sensors were adopted to measure the distance between the user and the robot. With the help of this ultrasonic sensors arrangement, the location of the user couldbe identified in all directions, which allowed the robot to follow the moving user at the desired distance. Experiments were carried out to see how well the user's location could be recognized and to investigate how accurately the robot trackedthe user, which eventually yielded a satisfactory performance.

• The Journal of Korea Robotics Society
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• v.19 no.1
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• pp.106-116
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• 2024

Ensuring robust 3D object detection is a core challenge for autonomous driving systems operating in urban environments. To tackle this issue, various 3D representation, including point cloud, voxels, and pillars, have been widely adopted, making use of LiDAR, Camera, and Radar sensors. These representations improved 3D object detection performance, but real-world urban scenarios with unexpected situations can still lead to numerous false positives, posing a challenge for robust 3D models. This paper presents a post-processing algorithm that dynamically adjusts object detection thresholds based on the distance from the ego-vehicle. While conventional perception algorithms typically employ a single threshold in post-processing, 3D models perform well in detecting nearby objects but may exhibit suboptimal performance for distant ones. The proposed algorithm tackles this issue by employing adaptive thresholds based on the distance from the ego-vehicle, minimizing false negatives and reducing false positives in the 3D model. The results show performance enhancements in the 3D model across a range of scenarios, encompassing not only typical urban road conditions but also scenarios involving adverse weather conditions.

• Journal of Arbitration Studies
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• v.31 no.4
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• pp.119-136
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• 2021

Due to the restriction of movement caused by the Corona epidemic and the expansion of the "big face" through human distance, the "unmanned system" based on artificial intelligence and the Internet of Things has been widely used in modern life. "Self-driving," one of the transportation systems based on artificial technology, has taken the initiative in the transportation system as the spread of Corona has begun. Self-driving technology eliminates unnecessary contact and saves time and manpower, which can significantly impact current and future transportation. Accidents may occur, however, due to the performance of self-driving technology during transportation albeit the U.S. allows ordinary people to drive automatically through experimental operations, and the product liability law will resolve the dispute. Self-driving has become popular in the U.S. after the experimental stage, and in the event of a self-driving accident, product liability should be applied to protect drivers from complicated self-driving disputes. The purpose of this paper is to investigate whether disputes caused by defects in ordinary cars can be resolved through arbitration through U.S. precedents and to investigate whether disputes caused by defects in autonomous cars can be arbitrated.

• Proceedings of the Acoustical Society of Korea Conference
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• 1987.11a
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• pp.17-19
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• 1987

In this paper an ultrasonic loud speaker (ie,. parametric speaker) driving technic was proposed. The study was focused on reduction of distortion in self-demodulated sound using a sound source deriven by MDSB(Modified Double Side Band) signal. And, the esperiment was performed in acoustic wave guide usin the developed MDSB unit according to the variation of distance from the source. In the result, prposed MDSB method was found to decrease second harnonic distortion in -3 to -6 dB compared to conventional DSB method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.587-590
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• 2000

By using the information obtained from output of the MR(Magneto Resistive) sensor for an unmanned vehicle system which is used in the Local Position System. We develop an algorithm that decides the distance and directions between the guideline made by magnets and vehicle, and make an unmanned vehicle driving system that is steered by PD controller and MR sensor

• Fashion & Textile Research Journal
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• v.20 no.1
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• pp.63-74
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• 2018

The purpose of this study is to investigate the differences in riding characteristics and helmet wearing conditions between bicycle and PMV riders so that the basis data necessary for the development of suitable helmets for each group is provided. For this purpose, riding characteristics and helmet wearing conditions of bicycle and PMV users were investigated using online survey method and then the survey results were interpreted by in-depth interview conducted for bicycle and PMV users. The online survey results showed that the PMV group showed shorter driving distance and more driving frequency than bicycle group. This short driving distance was due to the limitation of battery capacity of PMVs. Helmet wearing rate was significantly lower in PMV group than in bicycle group, which was associated with relatively low chances to drive long distance on the motorway. In the PMV group, the 'urban helmets' were mainly used, in which the appearance of helmet was priorized, but in the bicycle group, the 'road cycle helmets' were mainly used, in which the light weight or ventilation were priorized. Urban helmets caused stronger pain and more fitting problems than road cycle helmets because the head shapes of Koreans were not properly applied to the helmet design. Since the fitting problem and pain intensity were the important causes that making PMV users not wear the helmets, it is necessary to develop the urban helmets reflecting the head shapes of Koreans in order to increase the helmet wearing rate of the PMV users.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.111-122
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• 2013

PURPOSES : The purpose of this system (Rear Lighting System) is to provide illumination for the driver to operate the commercial vehicle safely after dark in highway, to increase the conspicuity of the vehicle, and especially be suggesting the finest observable improvement method, depending on color and pattern of rear lighting system of truck for midnight highway traffic. METHODS : Rear lightning system as an improving way for forward commercial vehicles lighting the securing sight from human factors and the surrounding environment in midnight driving. For this one, basic materials were collected from the data analysis about many types of problems, and filed investigation for establishing Driving Simulator. also taking statistic test to human volunteers after finding recognizable distance of them. RESULTS : As a result, color with the highest visuality is amber followed by green-red-blue as in order for all road types. Especially almost no difference is found between red and green, also when the light is turn off, recognizable distances is wide difference compared to turn on the light. One more thing about study per pattern, upper and entire lighting have similar recognizable distances, but under lighting shows short distance with difficulty securing sight from medians. And straight section shows similar recognizable distances. By finding visuality improvement method depending on color and pattern of supplement taillight, it is expected to suggest quantitative judgement standard for introducing regulation and improvement of supplement taillight. CONCLUSIONS : Night time vehicle conspicuity to the rear is provided by rear position lamps. this study is showed that the color of light ramp is not important to be safe driving, most important is to turn on the light, recognizable distances is big different compared to turn off the rear light, so when the drivng dark in highway, have to turn on the light for reducing risk.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.2
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• pp.27-35
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• 2022

Purpose : The purpose of this study is to analyze the correlation between the TPI Level 1 test and the performance of KPGA professional golf players. Methods : In 2019, 30 KPGA golf players attempted in the TPI Level 1 test. Their performance was then compared with the test based on the players' aggregated official records on the KPGA website, The most meaningful prize money ranking, average driving distance, fairway landing rate, and average number of putts were considered to evaluate their performance. Additionally, to obtain the average value of the players' accumulated records, the period from the first game in March 2019 to the end of October was considered. Results : The criterion for the difference between the upper group and the lower group was set based on the 9 points of the TPI Level 1 test, which showed the most significant difference. The prize money ranking stood at 63.00±51.77 in the upper group and 113.92±68.79 in the lower group in the TPI Level 1 test, the difference was significantly higher (p<.05) for the upper group (p<.05). The average driving distance was 286.15±10.06 yds for the upper group and 277.39±8.49 yds for the lower group, group, with the driving distance significantly higher in the upper group (p<.05). Further, the average number of putts for the upper group was 1.81±.02 and 1.85±.04 for the lower group, indicating a significant difference. Conclusion : A higher TPI Level 1 test score is likely to have a positive effect on performance.. As a result of the statistical values of this study, it was found that players must possess at least 9 out of 17 types of physical abilities Therefore, it can be considered that training and intervention to acquire these physical abilities are essential.