• Journal of the Korea Society of Computer and Information
• /
• v.17 no.1
• /
• pp.125-132
• /
• 2012

In this paper, We proposes FE-SM/SONN for recognizing blurred and smeared skid mark image caused by sudden braking of a vehicle. In a blurred and smeared skid marks, tread pattern image is ambiguous. To improve recognition of such image, FE-SM/SONN reads skid marks utilizing Fuzzy Logic and distinguishing tread pattern SONN(Self Organization Neural Networks) recognizer. In order to substantiate this finding, 48 tire models and 144 skid marks were compared and overall recognition ratio was 89%. This study showed 13.51% improved recognition compared to existing back propagation recognizer, and 8.78% improvement than FE-MCBP. The expected effect of this research is achieving recognition of ambiguous images by extracting distinguishing features, and the finding concludes that even when tread pattern image is in grey scale, Fuzzy Logic enables the tread pattern recognizable.

• Journal of Korean Society of Transportation
• /
• v.32 no.5
• /
• pp.522-530
• /
• 2014

Spatio-temporal congestion evolution pattern can be reproduced using the VDS(Vehicle Detection System) historic speed dataset in the TMC(Traffic Management Center)s. Such dataset provides a pool of spatio-temporally experienced traffic conditions. Traffic flow pattern is known as spatio-temporally recurred, and even non-recurrent congestion caused by incidents has patterns according to the incident conditions. These imply that the information should be useful for traffic prediction and traffic management. Traffic flow predictions are generally performed using black-box approaches such as neural network, genetic algorithm, and etc. Black-box approaches are not designed to provide an explanation of their modeling and reasoning process and not to estimate the benefits and the risks of the implementation of such a solution. TMCs are reluctant to employ the black-box approaches even though there are numerous valuable articles. This research proposes a more readily understandable and intuitively appealing data-driven approach and developes an algorithm for identifying congestion patterns for recurrent and non-recurrent congestion management and information provision.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.3
• /
• pp.225-232
• /
• 2014

In this study, a cooperative UAV and UGV platform is proposed to obtain a wide range of visual information. The UAV recognizes a pattern marker on UGV and tracks the UGV without user control. It can provide wide range of visual information for a user in the UGV. The UGV by a user is controled equipped with an aluminum board. And the UAV can take off and land on the UGV. The UAV uses two cameras; one camera is used to recognize a pattern marker and another is used to provide a wide range of visual information to the UGV's user. It is guaranteed that the proposed visual-based approach detects and tracks the target marker on the UGV, and then lands well. The experimental results show that the proposed approach can effectively construct a cooperative UAV/UGV platform for obtaining a wide range of vision information.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.15 no.4
• /
• pp.51-59
• /
• 2016

Measurements of the automobile manufacturers are available anywhere and anytime, directly based on the criterion of failure is measured. The maintenance of high-precision production activities is direct evidence of the fact that competitive manufacturing activities are very important in determining the success of companies to recall defective starting from raw material costs. The current manufacturing sites produce calipers and clearance gauge the degree of tool only specific. Therefore, judging the quality, including the number of errors, requires a lot of attention to the dimension failures in day-to-day measurements and measurement tasks and duties repeated in difficult situations. In this paper, we aim to develop a vehicle manufacturing plant site using each of the manufacturing processes while operating a measurement tool. We display it using the Image Processing PC-based S/W with all those visual facts by management and recorded as image information a more accurate and current situation to obtain information and share visual measurements. We carry out research on the design and development vision inspection algorithm applied for pattern-recognition techniques that can help manufacturing site quality control.

• Journal of Navigation and Port Research
• /
• v.45 no.6
• /
• pp.314-324
• /
• 2021

Competition between ports around the world is intensifying to attract transshipment cargo. However, recently, there have been concerns about the departure of transshipment cargo volume at Busan Port, such as the lifting of the cabotage policy in China's shipping sector and the implementation of a safe fare system. In terms of operation, terminal congestion and vehicle waiting time are seriously occurring due to imbalance in the transshipment volume of each terminal and vehicles concentrated in a specific time period. In this paper, we propose a method of inter-terminal transportation (ITT) using buffer space to solve the problem caused by inefficient ITT systems and presented a mixed integer programming (MIP) for the problem. The effect of using the buffer space was analyzed for various work volumes and capacity fluctuation ranges by applying the terminal congestion pattern and ITT vehicle in/out pattern based on the Busan New Port data.

• International Journal of Automotive Technology
• /
• v.4 no.2
• /
• pp.101-108
• /
• 2003

There are a lot of factors that influence automotive fuel economy such as average trip time per kilometer, average trip speed, the number of times of vehicle stationary, and so forth. These factors depend on road conditions and traffic environment. In this study, various driving data were measured and recorded during road tests in Seoul. The accumulated road test mileage is around 1,300 kilometers. The objective of the study is to identify the driving patterns of the Seoul metropolitan area and to analyze the fuel economy based on these driving patterns. The driving data which was acquired through road tests was analysed statistically in order to obtain the driving characteristics via modal analysis, speed analysis, and speed-acceleration analysis. Moreover, the driving data was analyzed by multivariate statistical techniques including correlation analysis, principal component analysis, and multiple linear regression analysis in order to obtain the relationships between influencing factors on fuel economy. The analyzed results show that the average speed is around 29.2 km/h, and the average fuel economy is 10.23 km/L. The vehicle speed of the Seoul metropolitan area is slower, and the stop-and-go operation is more frequent than FTP-75 test mode which is used for emission and fuel economy tests. The average trip time per kilometer is one of the most important factors in fuel consumption, and the increase of the average speed is desirable for reducing emissions and fuel consumption.

• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.838-843
• /
• 2008

Cause of struggling to escape from dependency of fossil fuels, the fuel cell and the Plug-in Hybrid Electric Vehicle (PHEV) draw attention in the all of the world. Especially, the Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems have been anticipated for next generation's energy supplying system, and we can predict the PHEV will enlarge the market share in the next few years to reduce not only the air pollution in the metropolis but the fuel-expenses of commuters. This paper presents simulation results about the strategy of smart charging system for PHEV in the residential house which has 1 kW PEMFC cogeneration system. The smart charging system has a function of recommending the best time to charge the battery of PHEV by the lowest energy cost. The simulated energy cost for charging the battery based on the electricity demand data pattern in the house. The house which floor area is $132\;m^2$ (40 pyeong.). In these conditions, the annual gasoline, electricity, and total energy cost to fuel the PHEV versus Conventional Vehicle (CV) have been simulated in terms of cars' average life span in Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.20 no.12
• /
• pp.789-794
• /
• 2008

Recently, much attention has been paid in the field of defrosting because clear windshield in vehicle without effecting the thermal comfort is realized essentially. Then in winter, defrosting performance is one of the important factors in vehicle design to make certain driver's view. In this study, the velocity profile, temperature distribution and frost melting pattern on the windshield screen have been predicted in three dimensional geometry of an automobile interior. Numerical analyses predict a detailed description of fluid flow and temperature patterns on the inside windshield screen, utilizing the flow through defroster nozzle. Numerical prediction established a good defrosting performance with the standard distance ratio and the defroster nozzle angle ranging from $30^{\circ}$ to $40^{\circ}$, which satisfy the condition of National Highway Traffic Safety Administration (NHTSA) completely.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.22 no.7
• /
• pp.16-22
• /
• 2014

Automotive NVH on brake operation is mainly caused by a coupling action of vehicle speed and inter parts friction and its frequency occurs over a broad band of 0.1 kHz~10 kHz. Especially, squeal noise, being a self-excited vibration generated by friction force between drum and lining, occurs over 1 kHz and consequently dynamic instability is induced when friction energy is applied to a brake vibration system. The squeal strongly depends on nonlinear properties influenced by the material of lining, velocity of vehicle, and the dynamic properties of a brake system. The dynamic properties are considered as a main influential design factor to squeal noise, however the analysis of the properties are rarely facilitated due to arbitrariness of shape by wearing down. In this paper, we research generating tendency of squeal noise through complex eigenvalue analysis, tracking drum brake's unstable modes in accordance with the wear shape of drum and lining such as tapered and bellmouth shape, and analyze computed unstable modes by variable shapes.

• Steel and Composite Structures
• /
• v.52 no.6
• /
• pp.609-620
• /
• 2024

The impact problem of imperfect beams is crucial in engineering fields such as water conservancy and transportation. In this paper, the low velocity impact of graphene reinforced metal foam beams with geometric defects is studied for the first time. Firstly, an improved Hertz contact theory is adopted to construct an accurate model of the contact force during the impact process, while establishing the initial conditions of the system. Subsequently, the classical theory was used to model the defective beam, and the motion equation was derived using Hamilton's principle. Then, the Galerkin method is applied to discretize the equation, and the Runge Kutta method is used for numerical analysis to obtain the dynamic response curve. Finally, convergence validation and comparison with existing literature are conducted. In addition, a detailed analysis was conducted on the sensitivity of various parameters, including graphene sheet (GPL) distribution pattern and mass fraction, porosity distribution type and coefficient, geometric dimensions of the beam, damping, prestress, and initial geometric defects of the beam. The results revealed a strong inhibitory effect of initial geometric defects on the impact response of beams.