• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.733-742
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• 2017

LADARs are used for important sensors in various applications, for example, terrain information sensors in self driving cars, safety sensors for factory automation, and 3D map constructions. This study develop important component technologies to improve the performance of a LADAR system under development in Korea. The component technologies include diode temperature regulation, reducing distance error in outdoor environment, and signal processing technique for better detection of distant objects. This paper explains the suggested component technologies and experimental results of the developed LADAR system. Also, the developed system is operated and tested an a single axis driving platform to acquire 3D information from 2D LADAR.

• Journal of Auto-vehicle Safety Association
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• v.13 no.1
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• pp.26-30
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• 2021

K-city is an experimental area for developing self-driving cars. V2X communications such as WAVE, C-V2X and 5G are an essential technology for autonomous driving above level 4. In this paper, the research on the V2V communication environment was carried out through BSM receiving level analysis on the driving route in K-city. A stationary vehicle communicated with a test vehicle moving along urban area and suburban road in two different scenarios. The communication range and receiving levels obtained from this study will be used to develop and verify various safety scenarios using V2V communication within K-city in the future.

• Korean Journal of Culture and Social Issue
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• v.14 no.2
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• pp.1-19
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• 2008

This research investigated the influences of excessively careful driving as well as chronic disease and medications on dangerousness of traffic accident in elderly drivers. Ninety-one drivers aged 65 years and older participated in the research. To evaluate the driving behavior, we used the self-rating on driving ability questionnaire asking driving speed, the amount of driving and driving situation adaptability' and surveyed the drive career, the number of violations and accidents experience(crash, crashed) for last three years. A review of the driving patterns of elderly drivers showed that the speed and amount of driving were decreased by increasing age. 'Driving- Situational Adaptability (DSA)' consisted of 2 factors such as 'Social Environment(SE)' and 'Physical Environment(PE)'. Elderly drivers reported that their confidence level was lower in PE than in SE. Moreover they had higher difficulty and stress in PE than in SE. DSA of elderly drivers had significant correlations with 'crash' and 'crashed'. This implies that excessively careful driving of elderly drivers directly associated with accidents. Elderly drivers who have nervous system disease or gastritis had more crash accidents. The majority of elderly drivers which take medicine by chronic disease don't think that medications give don't difficulty or inconvenience in driving and constantly drives during a term of taking medicine.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1777-1783
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• 2012

In this paper, a new motor driving circuit is designed to improve the output performance of DC motor, and a controller is developed with the designed circuit. By the designed driving circuit, a controller can continuously drive DC motors by a transformer which has switching signals of a self-generated circuit to operate it. And while the DC motor have a maximum velocity, the reference voltage can be maintained higher value than that of triangle voltage and it makes the DC motor driving transistor ON and maximum power. A 24V-500W DC motor controller is developed with the proposed motor driving circuit, and also a small electric car is made and the driving test of it is executed. The test results shows that it can continuously control go and back speed of motor with 12A driving current. And also, it is verified that the over current and heat detecting function is operating correctly and the rest value of the used battery can be displayed as 6 step from 20 to 100%.

• Proceedings of the KIPE Conference
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• 1996.06a
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• pp.80-84
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• 1996

A Switched Reluctance Motor(SRM) has a torque pulsating inherently due to characteristics of pulse driving. A torque pulsating causes noise and sound vibration. To reduce a noise, a torque pulsating shall be controlled. Many efforts to make flat-topped current has been proposed to minimize a torque pulsating up to now. This paper proposed a control scheme to minimize the vibration of SRM by controlling the vibration directly by using of self-turning technique. The experimental results show that the proposed control scheme is effective in reducing the torque ripple and noise.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.193-196
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• 1998

A new excitation method of switched reluctance motor drive is described in this paper. This excitation method produces reluctance torque by mutual action between two phases as well as conventional self reluctance torque due to two phase excitation at a time. In other words, the change of self inductance and mutual inductance are used to produce torque. This paper suggests the operational principle, the mechanism of torque product of switched reluctance motor with two phase excitation. The acoustic noise characteristics of two phase excitation method are described against that of conventional excitation method.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.39-50
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• 2007

This study investigated how drivers' cognitive characteristics, such as perception-motor skills and safety-seeking motivation; personal characteristics, such as sensation-seeking disposition coping with physical and social dangers; their self-perceived driving ability; and their normal driving behaviors influence the number of driving violations. 352 drivers participated in the study. MANOVA was performed in order to test the differences in their driving behaviors according to their level of sensation-seeking disposition and driving ability, and Structural Equation Modeling was used to examine the causal relationships among their demographic characteristics, sensation-seeking dispositions, driving ability, driving behaviors and the number of violations. The results indicated that drivers who had higher perception-motor skills seemed to be careful with pedestrians. From the results, drivers who had somewhat higher safety-seeking motivation tended to violate fewer traffic regulations intentionally or accidentally and showed more positive driving behaviors. Furthermore, drivers who had higher perception-motor skills, higher sensation-seeking disposition, and lower safety-seeking motivation had a tendency to violate intentionally more traffic regulations. The older drivers showed driving behaviors that were careful of pedestrians. The drivers who had higher sensation-seeking disposition and longer driving careers violated more traffic regulations, both intentionally and accidentally. Results from LISREL indicated that the predictive variables directly or indirectly influenced on drivers' violation numbers ($x^2$=341.62(p=.00), GFI=.94. RMR=.10).

• Journal of IKEEE
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• v.24 no.1
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• pp.243-247
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• 2020

As the autonomous driving market is rapidly growing, research on autonomous driving is being conducted. Self-driving functions should be performed regardless of the weather for the driver's safety. However, misty weather is difficult to autonomous driving because of the lack of visibility, so a defog algorithm should be used. The image obtained through the fog removal algorithm causes the image quality to deteriorate. To improve this problem, HSV color correction is used to increase the sharpness. In this paper, we propose a color correction hardware using HSV that can cope with 4K images. The hardware was designed with Verilog and verified by Modelsim. In addition, the FPGA was implemented with the goal of Xilinx's xc7z045-2ffg900.

• Journal of Auto-vehicle Safety Association
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• v.11 no.3
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• pp.30-36
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• 2019

This paper suggests a car-following algorithm for urban environment, with multiple target candidates. Until now, advanced driver assistant systems (ADASs) and self-driving technologies have been researched to cope with diverse possible scenarios. Among them, car-following driving has been formed the groundwork of autonomous vehicle for its integrity and flexibility to other modes such as smart cruise system (SCC) and platooning. Although the field has a rich history, most researches has been focused on the shape of target trajectory, such as the order of interpolated polynomial, in simple single-lane situation. However, to introduce the car-following mode in urban environment, realistic situation should be reflected: multi-lane road, target's unstable driving tendency, obstacles. Therefore, the suggested car-following system includes both in-lane preceding vehicle and other factors such as side-lane targets. The algorithm is comprised of three parts: path candidate generation and optimal trajectory selection. In the first part, initial guesses of desired paths are calculated as polynomial function connecting host vehicle's state and vicinal vehicle's predicted future states. In the second part, final target trajectory is selected using quadratic cost function reflecting safeness, control input efficiency, and initial objective such as velocity. Finally, adjusted path and control input are calculated using model predictive control (MPC). The suggested algorithm's performance is verified using off-line simulation using Matlab; the results shows reasonable car-following motion planning.

• The Research Journal of the Costume Culture
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• v.20 no.4
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• pp.604-615
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• 2012

Despite the increasing recognition of the value of emotions and younger consumers in luxury market segments, little research has focused on the role consumer characteristics and emotions play in younger consumers' commitment to luxury brands. Drawing on the identity-motivation model and the idea of self-construal, this study identifies the contributing factors of younger consumers' commitment to luxury fashion brands. Specifically, this study examines the role of consumer characteristics (i.e., self-construal), the self-expressiveness of brands, and emotional factors (i.e., brand love and brand attachment) in developing consumer-brand relationships. The proposed model was tested with college students in the U.S., which supplied a representative group of younger consumers of luxury fashion brands. The data were collected using web-based surveys and analyzed using structural equation modeling method. The results showed that consumers who were characterized with interdependent self-construal had positive perceptions of self-expressive luxury fashion brands. Furthermore, the perception of self-expressive brands promotes the consumers' brand love of and brand attachmentto luxury fashion brands. Also, while both improved brand commitment, brand attachment had a greater impact on brand commitment than brand love. This study contributes to the literature by identifying driving forces of younger consumers' brand commitment. It also provides managerial implications for luxury fashion brands.