• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.4002-4006
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• 2014

The automotive exhaust gases generated by the vehicles containing carbon monoxide, hydrocarbons and lead, is a large concern because of their harm to human health or the living environment. To reduce exhaust gas, it is important to develop a variety of techniques that are currently being used by elemental analysis to determine the optimal conditions. In this study, the anti-freeze coolant contained in the exhaust gas was examined, which can affect the emissions. The effects of the commercially available coolant from five domestic companies on the HC, NOx and $CO_2$ emissions were analyzed to determine the optimal amount of antifreeze. In addition, antifreeze products from the five companies were analyzed with respect to driving time of the cooling fan and the correlation of the NOx emission analysis. The temperature of the engine oil was matched using a manual gear of small passenger inspection standard speed $40{\pm}2Km/h$ so the vehicle could meet the specifications for inspection $90{\sim}93^{\circ}C$. The Company D fan operation time resulted in the shortest antifreeze, $CO_2$ and NOx emissions.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.53-64
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• 2013

The car-following model is one of core models in Advanced Vehicle & Highway Systems (AVHS). The car-following model has been developed in aspects such as human factor and reduction error rates. However, the consideration of safety depending on weather condition has not been completed yet. In this paper, therefore, changes of driving condition for car-following due to different road condition were dealt with, and optimal safety distance corresponding to road condition such as dry, wet and snowy were computed. The GMIT(GM Model with Instantaneous T) model was picked over for simulation of adaptive cruise control applied the suggested optimal safety distance. As the results, the 1.7 times longer safety distance was required for wet road condition than dry road condition, and the 5.6 times longer safety distance was required for snowy road condition.

• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.689-697
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• 2015

The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome.

• Journal of Korean Society of Transportation
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• v.30 no.5
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• pp.11-21
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• 2012

As a strategy to enhance traffic management, roundabouts come to the fore recently to decrease traffic accidents, streamline traffic flows, and expedite the realization of green transportation. As local governments introduced roundabouts, new road sign standards have to be established because the existing road sign regulations cannot be applied to roundabouts. Prior to trying to make suitable specification of sub-destination signs in roundabouts, regulations of other countries were examined and modified. The legend and location was calculated so that drivers could turn in time. Two specifications were determined by simulation experiments. As a result, drivers could read signs at right side better than at traffic island, and turn in time at 15cm legend size. Consequently, we proposed the minimum specifications and optimal locations of sub-destination signs.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.3
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• pp.22-30
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• 2006

In this paper, a systematic design method on an IPMC(ionic polymer-metal composite)-driven ZNMF(zero-net-mass-flux) pump is introduced for the flow control of an MAV's (micro air vehicle) wing. Since the IPMC is able to generate a large deformation under a low input voltage along with its ability to operate in air, and is easier to be manufactured in a small size, it is considered to be an ideal material of the actuating diaphragm. Through the numerical methods, an optimal shape of the IPMC　diaphragm was found for maximizing the stroke volume. Based on the optimal IPMC diaphragm, a proto-type ZNMF pump with a slot, was designed. By using the flight speed of the MAV considered in this work, the driving frequencies(~ 40 Hz) of IPMC diaphragm, and the flow velocity through the pump's slot, the calculated non-dimensional frequency and the momentum coefficient ensure the feasibility of the designed ZNMF pump as a flow control device.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.3
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• pp.79-85
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• 2014

For the successful operation of unmanned ground vehicles(UGVs), optimal path planning should be considered with trafficability analysis, threat analysis, and so on. From among these, trafficability analysis is immensely important for safeness of UGVs especially in the case of driving the off-road such as unpaved road, grassland, and open fields. Geographical information has a pivotal role in extracting data and measuring cost for specified regions of interest. In this paper, we review possibilities to apply Land Cover Map(LCM) as a new, fundamental source and propose a new generation method of trafficability analysis map for optimal path planning of UGV. The simulation results show that the proposed method significantly improve the previous method by applying LCM either alone or in combination with the other GIS.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.3
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• pp.339-349
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• 2017

This paper proposes a four-stage algorithm for detecting lanes on a driving car. In the first stage, it extracts region of interests in an image. In the second stage, it employs a median filter to remove noise. In the third stage, a binary algorithm is used to classify two classes of backgrond and foreground of an input image. Finally, an image erosion algorithm is utilized to obtain clear lanes by removing noises and edges remained after the binary process. However, the proposed lane detection algorithm requires high computational time. To address this issue, this paper presents a parallel implementation of a real-time line detection algorithm on a multi-core architecture. In addition, we implement and simulate 8 different processing element (PE) architectures to select an optimal PE architecture for the target application. Experimental results indicate that 40×40 PE architecture show the best performance, energy efficiency and area efficiency.

• Journal of Hydrogen and New Energy
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• v.25 no.5
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• pp.516-524
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• 2014

Proper discharge of nitrogen gas and water condensate is required in a conventional fuel cell system for performance, stability and durability of fuel cell stacks. Present study covers the development of integrated unit and its functioning logic for simultaneous nitrogen gas purge and water condensate drainage in a fuel cell vehicle system. Configuration of condensate drainage pipe, purge valve and level sensor is considered and optimized in physical integration. As a key factor, discharge time is considered and optimized based on the test result of constant-current operation with various operating temperature in logic development. Consequently, derived optimal values are applied and verified in actual vehicle drive mode test. Increase of system design flexibility, weight reduction and cost reduction are anticipated with this study. Additional study for physical and logical improvement is currently being implemented.

• International Journal of Railway
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• v.2 no.2
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• pp.50-59
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• 2009

Numerous train operating companies provide training by means of driving simulators. A detailed analysis in the course of the rail research project 2TRAIN has shown that the simulation technology, the purposes of training and the overall concept of simulator-based training are rather diverse (Schmitz & Maag, 2008). A joint factor however are weak assessment capabilities and the fact that the simulator training is often not embedded into the overall competence management. This fact hinders an optimal use of the simulators. Therefore, 2TRAIN aims at the development of enhanced training and assessment tools. Taking into account that several simulators are already in use, the focus lays on the extension of existing simulation technology instead of developing entirely new systems. This extension comprises (1) a common data simulation interface (CDSI), (2) a rule-based expert system (ExSys), (3) a virtual instructor (VI), and (4) an _assessment database (AssDB). The foundation of this technical development is an assessment concept (PERMA concept) that is based on performance markers. The first part of the paper presents this assessment concept and a process model for the two major steps of driver performance assessment, i.e. (1) the specification of exercise and assessment and (2) the assessment algorithm and execution of the assessment. The second part describes the rationale and the functionalities of the simulator add-on tools. Finally, recommendations for further technical improvement and appropriate usage are given. based on the results of a pilot study.

• The Journal of Korea Robotics Society
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• v.3 no.3
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• pp.186-193
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• 2008

We propose a novel real-time obstacle avoidance method for rescue robots. This method, named the ELA(Emergency Level Around), permits the detection of unknown obstacles and avoids collisions while simultaneously steering the mobile robot toward safe position. In the ELA, we consider two sensor modules, PSD(Position Sensitive Detector) infrared sensors taking charge of obstacle detection in short distance and LMS(Laser Measurement System) in long distance respectively. Hence if a robot recognizes an obstacle ahead by PSD infrared sensors first, and judges impossibility to overcome the obstacle based on driving mode decision process, the order of priority is transferred to LMS which collects data of radial distance centered on the robot to avoid the confronted obstacle. After gathering radial information, the ELA algorithm estimates emergency level around a robot and generates a polar histogram based on the emergency level to judge where the optimal free space is. Finally, steering angle is determined to guarantee rotation to randomly direction as well as robot width for safe avoidance. Simulation results from wandering in closed local area which includes various obstacles and different conditions demonstrate the power of the ELA.