• Title/Summary/Keyword: Driving Distance

Search Result 664, Processing Time 0.022 seconds

A Study on the Re-establishment of Selection Criterion on the Frequency of Foggy Area in Highway (고속도로 안개 잦은 구간 선정 기준 재정립에 관한 연구)

  • Jung, Sung-Hwa;Lee, Soo-Beom;Park, Jun-Tae;Lee, Soo-Il;Hong, Ji-Yeon
    • Journal of the Korean Society of Safety
    • /
    • v.26 no.2
    • /
    • pp.99-106
    • /
    • 2011
  • There is a high potentiality of large traffic accident due to the dense fog when road is developed along the coast or river. The establishment of national level control system against the fog is necessary because the accident due to the creation of fog has a high fatality ratio than other weather conditions. The selection method for the frequent foggy area on highway was suggested to control the fog on the highway effectively because the establishment of the countermeasure against the fog in every range in highway is difficult practically. 44 ranges where the fog control is necessary throughout the year and the 45 ranges where the control is necessary in specific months were selected from the result of application of the weighted value on each visible distance data except the fog with beyond 250 m visible distance which does not affect on the safe driving out of the surveyedjsh fog visible distances. The preferential fog control countermeasure shall be provided to prevent the traffic accident and to reduce the severeness of the accident in case of fog creation for 89 ranges which were selected for frequent foggy area in highway.

Improvement of Muzzle Localization Using Linear Microphone Array (선형마이크로폰 어레이를 이용한 총구 거리 추정 개선 방법)

  • Jung, Seong-Woo;Kim, Yang-Hann
    • The Journal of the Acoustical Society of Korea
    • /
    • v.34 no.1
    • /
    • pp.60-65
    • /
    • 2015
  • In this paper, we used the sound of gunshots recorded by multiple microphones to increase the accuracy of the calculation of the distance between sniper and the microphone array. This method is crucial for achieving military objectives. Gunshots are comprised of the explosion of driving gas from the muzzle and the supersonic shock wave from the flying bullet. The original distance calculation method compares the time difference of arrival and angle of incidence to estimate the sniper's location. The disadvantage of this method is that when the angles of incidence coincide the margin of error increases, to solve this problem we suggest a new method using the characteristic changes of the shock wave with the increase of perpendicular distance between the microphone and the trajectory of the bullet. This theory is verified by experiments.

Does the China-Korea Free Trade Area Promote the Green Total Factor Productivity of China's Manufacturing Industry?

  • Liu, Zuan-Kuo;Cao, Fei-Fei;Dennis, Bolayog
    • Journal of Korea Trade
    • /
    • v.23 no.5
    • /
    • pp.27-44
    • /
    • 2019
  • Purpose - The purpose of this paper is to analyze the net effect of the green total factor productivity (GTFP) of China's manufacturing industry from the China-Korea Free Trade Area (China-Korea FTA) quantitatively. Design/methodology - Firstly, the Global Malmquist-Luenberger (GML) index based on the SBM directional distance function is used to measure the GTFP of China's manufacturing and analyze the driving force for its growth. Secondly, the regression discontinuity quantitative analysis is used to determine the impact of the China-Korea FTA on China's manufacturing GTFP. Findings - Our main findings can be summarized as follows: the China-Korea FTA has promoted the GTFP of China's manufacturing with an effect evaluation mainly resulting from green technology progress. And there is industry heterogeneity in the policy effect on the manufacturing GTFP due to the China-Korea FTA. Namely, policy promotion from the China-Korea FTA is more effective on the GTFP of equipment manufacturing than it is on those of other industries. Originality/value - First, an evaluation and analysis of the GTFP development of China's manufacturing that employs GML index based on SBM directional distance function. Second, a quantitative estimate of China-Korea FTA's net effect on China's manufacturing industrial GTFP that uses regression discontinuity analysis, which is considered to be the closest method to natural experiments and superior to other causal inference methods. Third, an in-depth discussion of the practical steps that China's manufacturing can take to improve GTFP development and integrate China-Korea FTA construction into economic development.

BLE-based Indoor Positioning System design using Neural Network (신경망을 이용한 BLE 기반 실내 측위 시스템 설계)

  • Shin, Kwang-Seong;Lee, Heekwon;Youm, Sungkwan
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.25 no.1
    • /
    • pp.75-80
    • /
    • 2021
  • Positioning technology is performing important functions in augmented reality, smart factory, and autonomous driving. Among the positioning techniques, the positioning method using beacons has been considered a challenging task due to the deviation of the RSSI value. In this study, the position of a moving object is predicted by training a neural network that takes the RSSI value of the receiver as an input and the distance as the target value. To do this, the measured distance versus RSSI was collected. A neural network was introduced to create synthetic data from the collected actual data. Based on this neural network, the RSSI value versus distance was predicted. The real value of RSSI was obtained as a neural network for generating synthetic data, and based on this value, the coordinates of the object were estimated by learning a neural network that tracks the location of a terminal in a virtual environment.

Analysis of Low-power-based Communication Technology to Build a Mobility Connected System (모빌리티 커넥티드 시스템 구축을 위한 저전력 기반 통신 기술 분석)

  • Sung-goo Yoo;Ju-yeon Lee
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.25 no.1
    • /
    • pp.33-38
    • /
    • 2024
  • The importance of connected technology that connects products or systems is increasing. Connected technology is a concept that can communicate with surrounding objects and connect to each other through a network to operate as one system. In particular, it can be implemented using wireless communication, and various conditions are required depending on the application system, such as communication distance and speed. In this study, we analyzed trends in communication technology for the implementation of connectivity between mobility devices such as self-driving cars, drones, UAVs, and shared mobility devices. The communication distance, speed, wired and wireless status, etc. of the latest communication methods currently commercialized or under development were investigated, with a particular focus on low-power operation. We identified the element technologies needed to build a low-power long-distance communication (LPWAN) system, and initially developed a plan for constructing a connected drone. The analysis results showed that it was possible to implement a connected system using the LoRa system, and an example configuration method was presented.

A Methodology for Evaluating Vehicle Driving Safety based on the Analysis of Interactions With Roads and Adjacent Vehicles (도로 및 인접차량과의 상호작용분석을 통한 차량의 주행안전성 평가기법 개발 연구)

  • PARK, Jaehong;OH, Cheol;YUN, Dukgeun
    • Journal of Korean Society of Transportation
    • /
    • v.35 no.2
    • /
    • pp.116-128
    • /
    • 2017
  • Traffic accidents can be defined as a physical collision event of vehicles occurred instantaneously when drivers do not perceive the surrounding vehicles and roadway environments properly. Therefore, detecting the high potential events that cause traffic accidents with monitoring the interactions among the surroundings continuously by driver is the prerequisite for prevention the traffic accidents. For the analysis, basic data were collected to analyze interactions using a test vehicle which is equipped the GPS(Global Positioning System)-IMU(Inertial Measurement Unit), camera, radar and RiDAR. From the collected data, highway geometric information and the surrounding traffic situation were analyzed and then safety evaluation algorithm for driving vehicle was developed. In order to detect a dangerous event of interaction with surrounding vehicles, locations and speed data of surrounding vehicles acquired from the radar sensor were used. Using the collected data, the tangent and curve section were divided and the driving safety evaluation algorithm which is considered the highway geometric characteristic were developed. This study also proposed an algorithm that can assess the possibility of collision against surrounding vehicles considering the characteristics of geometric road structure. The methodology proposed in this study is expected to be utilized in the fields of autonomous vehicles in the future since this methodology can assess the driving safety using collectible data from vehicle's sensors.

Estimating a Range of Lane Departure Allowance based on Road Alignment in an Autonomous Driving Vehicle (자율주행 차량의 도로 평면선형 기반 차로이탈 허용 범위 산정)

  • Kim, Youngmin;Kim, Hyoungsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.15 no.4
    • /
    • pp.81-90
    • /
    • 2016
  • As an autonomous driving vehicle (AV) need to cope with external road conditions by itself, its perception performance for road environment should be better than that of a human driver. A vision sensor, one of AV sensors, performs lane detection function to percept road environment for performing safe vehicle steering, which relates to define vehicle heading and lane departure prevention. Performance standards for a vision sensor in an ADAS(Advanced Driver Assistance System) focus on the function of 'driver assistance', not on the perception of 'independent situation'. So the performance requirements for a vision sensor in AV may different from those in an ADAS. In assuming that an AV keep previous steering due to lane detection failure, this study calculated lane departure distances between the AV location following curved road alignment and the other one driving to the straight in a curved section. We analysed lane departure distance and time with respect to the allowance of lane detection malfunction of an AV vision sensor. With the results, we found that an AV would encounter a critical lane departure situation if a vision sensor loses lane detection over 1 second. Therefore, it is concluded that the performance standards for an AV should contain more severe lane departure situations than those of an ADAS.

A Study on Design and Implementation of Driver's Blind Spot Assist System Using CNN Technique (CNN 기법을 활용한 운전자 시선 사각지대 보조 시스템 설계 및 구현 연구)

  • Lim, Seung-Cheol;Go, Jae-Seung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.20 no.2
    • /
    • pp.149-155
    • /
    • 2020
  • The Korea Highway Traffic Authority provides statistics that analyze the causes of traffic accidents that occurred since 2015 using the Traffic Accident Analysis System (TAAS). it was reported Through TAAS that the driver's forward carelessness was the main cause of traffic accidents in 2018. As statistics on the cause of traffic accidents, 51.2 percent used mobile phones and watched DMB while driving, 14 percent did not secure safe distance, and 3.6 percent violated their duty to protect pedestrians, representing a total of 68.8 percent. In this paper, we propose a system that has improved the advanced driver assistance system ADAS (Advanced Driver Assistance Systems) by utilizing CNN (Convolutional Neural Network) among the algorithms of Deep Learning. The proposed system learns a model that classifies the movement of the driver's face and eyes using Conv2D techniques which are mainly used for Image processing, while recognizing and detecting objects around the vehicle with cameras attached to the front of the vehicle to recognize the driving environment. Then, using the learned visual steering model and driving environment data, the hazard is classified and detected in three stages, depending on the driver's view and driving environment to assist the driver with the forward and blind spots.

Development of a Crawler Type Vehicle to Travel in Water Paddy Rice Field for Water-Dropwort Harvest

  • Jun, Hyeon-Jong;Kang, Tae-Gyoung;Choi, Yong;Choi, Il-Su;Choi, Duck-Kyu;Lee, Choung-Keun
    • Journal of Biosystems Engineering
    • /
    • v.38 no.4
    • /
    • pp.240-247
    • /
    • 2013
  • Purpose: This study was conducted to develop a rubber-crawler type vehicle as a traveling device for harvesting water-dropwort cultivated in water contained paddy rice field in winter season. Methods: A commercial rubber-crawler type vehicle was used to investigate application of rubber crawler to the paddy rice field as preliminary test. As the result of the preliminary test, a both prototype traveling device with rubber crawlers for a water-dropwort harvest was designed with inclination of $45^{\circ}$ at the front-end and rear-end of crawler under the basic water depth of 0.6 m in the paddy rice field. The device was fabricated and attached to the experimental harvesting test devices on the front of the prototype vehicle. The size of the prototype crawler vehicle with a harvesting part is $2,800{\times}1,460{\times}1,040 $ (mm) ($L{\times}W{\times}H$) with weight of 9.21 kN (maximum). Sizes of the crawler of prototype vehicle are ground contact length of 900 mm, width of 180 mm, height of 1,070 mm and distance between center to center of crawlers of 720 mm. The side-overturn angle of the prototype was $26.4^{\circ}$. Results: Driving performance of the prototype vehicle in water contained paddy field were good at both forward and reverse (backward) directions as weights were applied. The drawbar pull and the maximum sinking depth of the prototype vehicle were 3.5 kN and 0.13 m respectively at water depth of 0.5 m, when the weight and bearing capacity of the prototype rubber crawler in the paddy field were 8.51 kN and 26.3 $kN/m^2$, respectively. Conclusions: Results of the driving test performance of the prototype crawler in paddy rice field at the water depth of 0.5 m were satisfactory. The prototype had enough drawbar pull and driving ability in the deep water contained paddy field.

Can Traditional Industry Firms Be Born Global? Case Study with a Focus on Chinese and Korean Firms

  • Kang, Qingsong;Yoon, Ki-Chang;Park, Joshua
    • Journal of Korea Trade
    • /
    • v.24 no.6
    • /
    • pp.135-156
    • /
    • 2020
  • Purpose - This study investigates whether the internationalization process of traditional industry firms can be categorized as born global, early internationalization, or gradual internationalization, and examines what factors promote internationalization in traditional industries using a case study of two firms, one each in China and Korea. Design/methodology - This study elects to use case study methodology to determine the "how" and "why" of internationalization process of traditional industry firms. Taking into consideration that factors that impact the internationalization process of firms are diverse and unclear in terms of causality, this study utilizes exploratory case study methodology. This research performs a comparative two-case study of two firms in traditional industries, one each in China and Korea, to examine similarities and differences of study subjects in order to improve the validity and suitability of research results. Findings - The findings of this research are as follows: First, traditional industries are more likely go through early and rapid internationalization rather than being born global; born globals are far more likely to appear in high tech industries. Second, the internationalization process of companies that go through early and rapid internationalization differs from what is indicated by traditional internationalization theories, and are not limited by factors like psychological distance and lack of experiential knowledge. Third, international entrepreneurship, international market orientation, and imitation and learning are important internal driving factors for early and rapid internationalization. Fourth, conditions within the domestic market, policy support from the government, and pilot effect from industry leaders are external driving factors for early and rapid internationalization. Originality/value - This study shows that the internationalization process of traditional industry firms is more likely to be early and rapid internationalization rather than being born global and suggests answers to why this may be the case. In addition, through an examination of case studies, it reveals that the internationalization process of traditional industry firms that undergo early and rapid internationalization is different from traditional internationalization theory, in that they are not limited by the lack of psychological proximity and empirical knowledge, and are driven by international entrepreneurship, international market orientation, imitation and learning, competitive pressure within the domestic market, government's policy support, and the pilot effect of industry leaders. Therefore, this study contributes to literature by expanding the scope of application of born global theory to traditional industries, making born global theory more generalizable and identifying driving factors to internationalization of traditional industry firms.