• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.11
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• pp.84-91
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• 2009

A high speed serial link transmitter using multi-level signaling is proposed. To achieve high data rate m high speed serial link, 4-pulse amplitude modulation (PAM) is used. By transmitting 2 bit data in each symbol time, high speed data transmission, two times than binary signaling, is achieved. The transmitter transmits current-mode output instead of voltage-mode output Current-mode output is much faster than voltage-mode output, so higher data transmission is available by increasing switching speed of driver. $2^5-1$ pseudo-random bit sequence (PRBS) generator is contained to perform built-in self test (BIST). The 4-PAM transmitter is designed in Dongbu HiTek $0.18{\mu}m$ CMOS technology and achieves 8 Gb/s, 160 mV of eye height with 1.8 V supply voltage. The transmitter consumes only 98 mW for 8 Gb/s transmission.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.4
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• pp.81-86
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• 2020

With the development of the intelligent Internet of Things AIoT that goes beyond the IoT of the Internet of Things, the industry is changing overall. In addition, with the advent of the 4th Industrial Revolution, revolutionary changes and developments are also taking place in the automobile industry. A representative example is "autonomous driving vehicle". Because the domestic and foreign interests in autonomous vehicles have increased, many developments have been made, and although limited, they have developed into the commercialization stage. However, the structure of the autonomous vehicle that collects, analyzes, and controls data using various sensors installed in the vehicle, not the driver, is often insufficiently exposed to hacking due to the lack of multiplexed devices for security. In this case, as this can be a threat not only to the driver, but also to the surrounding environment, this paper proposes a new data processing function to improve the system security of autonomous vehicles.

• Research in Community and Public Health Nursing
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• v.16 no.4
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• pp.517-526
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• 2005

Purpose: The purpose of this study is to find taxi drivers' smoking behavior, self-efficacy and expectation level of success in smoking cessation. It will provide useful information for developing nursing interventions in health promotion programs. Method: The subjects of this study were 271 taxi drivers in Seoul and its metropolitan area. Data were collected using a self-reported questionnaire asking smoking history, smoking behaviors, health problem, stages of change for smoking cessation, self-efficacy and the expectation level of success in smoking cessation. Data were analyzed through descriptive statistics. Pearson's correlation, Mann-Whitney U test, Kruskal-Wallis test and Cronbach's a. Results: Of the taxi drivers, 83.8% were current smokers. Stages of change were as follows: 45.8% were in the precontemplation stage, 26.2% in the contemplation stage, 13.7% in the maintenance stage, 12.2% in the preparation stage and 1.5% in the action stage. In addition. 20.3% of the subjects reported health problems such as hypertension, heart disease, diabetes mellitus and respiratory disease. The expectation level of success in smoking cessation was positively related with self-efficacy. There were statistically significant differences in the expectation level of success in smoking cessation according to the number of cigarettes per day and nicotine dependency. In addition. there were statistically significant differences in self-efficacy according to the number of cigarettes per day, duration of smoking (years) and nicotine dependency. Conclusion: The results of this study suggest that taxi drivers' health problems and smoking rate were serious. Therefore more systematic health promotion programs for smoking cessation should be developed and executed by health care specialists at individual taxi companies.

• Journal of the Korean GEO-environmental Society
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• v.21 no.11
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• pp.5-10
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• 2020

Although pile driver overturning accidents at construction site are not frequent, most leads to serious disasters. The main cause of accidents is uneven settlement of the ground. To prevent this, related guidelines such as KOSHA-C-101-2014, KOSH-A-GUIDE-71-2012, Occupational Safety and Health Standards, and NCS stipulate the installation of steel plates over ground. However, since the required steel plate thickness considering the self-weight of pile drivers and the underlying ground condition is not quantitatively presented, it is randomly applied in the field. In this study, the required minimum steel plate thickness was analyzed based on a numerical analysis (Plaxis 2D). Settlements and soil failure were calculated according to the different type of soils (sand, clay), load distribution and steel plate thickness (10mm, 20mm, 30mm, 40mm). Under all conditions, 10mm steel plate causes soil collapse. From thickness 20mm, the ground uneven subsidence is within 2° of the allowable leader angle.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.199-207
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• 2002

This is a study to evaluate the effects of the safety of ambulance driving and the occurrence of ambulance traffic accidents and to provide basic information for the description of various factors to reduce the ambulance traffic accidents. The major instruments of this study were Korean Self-Analysis Driver Opinionnaire. Questionnaire contains 8 items which measure driver's opinions or attitudees: driving courtesy, emotion, traffic law, speed, vehicle condition, the use of drugs, high-risk behavior, human factor. To take the analysis of data, the total of 187 drivers were investigated ambulance drivers in Gwangju Metropolitan City from 2002. 1. September to 2002. 20. September. The data were analyzed by the path analysis SPSS program. The result are as follows : 1. There was desirable attitude group(58.4%) and undesirable attitude group(41.7%) on safety ambulance driving. 2. It have suggested that rist factors of ambulance traffic accident much affected with emotion and speed control on safety ambulance driving(Y(Accident) = -2.00 + 0.6 X1(Emotion Control) + 0.4 $X_2$(Speed control) + E). 3. Almost 92.1% of respondents have agreed to necessity of emergency medical technics for ambulance drivers.

• Korean Journal of Occupational Health Nursing
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• v.24 no.4
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• pp.363-371
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• 2015

Purpose: The purpose of this study was to investigate the factors influencing health promoting lifestyle of urban bus driver in small-sized companies. Methods: This study included 118 urban bus drivers who completed questionnaires. The data were collected from 6 small-sized bus companies located in a metropolitan city, from January to February 2015. Analyses were done using descriptive statistics, independent t-test, ANOVA, Pearson's correlation, and multiple regression analysis. SPSS/Win 18.0 was used. Results: The scores of HPLP of urban bus drivers were 2.7 (on a 4-point scale). Mean of HPLP sub-scores were self-fulfillment ($3.0{\pm}0.5$), interpersonal relationship ($2.9{\pm}0.5$), physical activity ($2.9{\pm}0.7$), health responsibility ($2.7{\pm}0.5$), healthy diet ($2.6{\pm}0.6$), and stress management ($2.5{\pm}0.5$). Among independent variables, job satisfaction and presence of religion were significantly related to health promoting lifestyle (explained 39.2%). Conclusions: This study revealed that there is a need to strengthen job satisfaction for urban bus drivers' health promoting lifestyle.

• Journal of the Korea Society of Computer and Information
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• v.22 no.10
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• pp.47-54
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• 2017

In this paper, we propose a connected car platform architecture called Mobile Second for developing of verity convergence services. A Mobile Second platform architecture is designed to provide more powerful and diverse convergence services for vehicles and drivers by applying technologies of Connected Car and ICT Convergence in various ways. The Mobile Second platform is implemented by applying Tizen IVI and Android to hardware platforms for IVI, Nexcom's VTC1010 and Freescale's i.MX6q/dl respectively. The Mobile Second platform provides the driver with the vehicle's information via IVI devices, mobile devices and PCs, etc., and provides Vehicle Selective Gateway(VSG) and Vehicle Control Framework for the driver to control his/her vehicle, and also provides a web framework to enable the use of VSG's APIs for the monitoring and controlling the vehicle information in various mobile environments as well as IVI devices. Since the Mobile Second platform aims to create new variety of services for Connected Car, it includes service frameworks for Smart Care / Self diagonostics, Mood & Entertainment services, and Runtime, libraries and APIs needed for the development of related applications. The libraries given by the Mobile Second Platform provides both a native library for native application support and a Java Script-based library for web application support, minimizing the dependency on the platform and contributing the convenience of developers at the same time.

• Journal of Power Electronics
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• v.19 no.1
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• pp.68-78
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• 2019

The emergence of high voltage conversion applications has resulted in a trend of using semiconductor device series associations. Series associations allow for operation at blocking voltages, which are higher than the nominal voltage for each of the semiconductor devices. The main challenge with these topologies is finding a way to guarantee the voltage balance between devices in both blocking and switching transients. Most of the methods that have been proposed to mitigate static and dynamic voltage unbalances result in increased losses within the device. This paper introduces a new series stack topology, where the voltage unbalances are reduced. This in turn, mitigates the switching losses. The proposed topology consists of a circuit that ensures the soft switching of each device, and one auxiliary circuit that allows for switching energy recovery. The principle for the topology operation is presented and experimental tests are performed for two modules. The topology performs excellently for switching transients on each of the devices. The voltage static unbalances were limited to 10%, while the activation/deactivation delay introduced by the lower module IGBT driver takes place in the dynamic unbalances. Thus, the switching losses are reduced by 40%, when compared to hard switching configurations.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.142-148
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• 2023

In Modern days, Self-driving for modern people is an absolute necessity for transportation and many other reasons. Additionally, after the outbreak of COVID-19, driving by oneself is preferred over other means of transportation for the prevention of infection. However, due to the constant exposure to stressful situations and chronic fatigue one experiences from the work or the traffic to and from it, modern drivers often drive under drowsiness which can lead to serious accidents and fatality. To address this problem, we propose a drowsy driving prevention learning model which detects a driver's state of drowsiness. Furthermore, a method to sound a warning message after drowsiness detection is also presented. This is to use MoveNet to quickly and accurately extract the keypoints of the body of the driver and Dense Neural Network(DNN) to train on real-time driving behaviors, which then immediately warns if an abnormal drowsy posture is detected. With this method, we expect reduction in traffic accident and enhancement in overall traffic safety.

• Journal of Convergence for Information Technology
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• v.10 no.7
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• pp.223-231
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• 2020

Older drivers have an increased risk of accidents due to poor function, but they also develop self-regulation ability to check their own changes. Thus, information on whether the actual elderly driver responds to changes in driving ability and risk may provide a meaningful basis for the clinic and research of the elderly's driving ability assessment. Therefore, the purpose of this study is to provide basic data for the evaluation of elderly drivers by analyzing the driving risk self-perception characteristics in terms of driving behavior and function with Korean elderly drivers. A self-reporting assessment was conducted on 500 elderly drivers living in the community and the characteristics of driving risk perception were analyzed. As a result, it was confirmed that many elderly drivers are aware of the driving risk when their vision and hearing are impaired or when they find it difficult to adapt to changes in driving conditions. On the other hand, the characteristics of insensitive reactions to changes in medical health conditions, such as drug use or epilepsy, seizures, and loss of consciousness, were identified. The researcher hopes this study will contribute to the safety management of elderly drivers in Korea, where aging is accelerating.