• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1496-1499
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• 2004

In this paper, we deal with a novel path planning algorithm to find collision-free path for a moving robot to find an appropriate path from initial position to goal position. The robot should make progress by avoiding obstacles located at unknown position. Such problem is called the path planning. We propose so called the subgoal generation algorithm to find an effective collision-free path. The generation and selection of the subgoal are the key point of this algorithm. Several subgoals, if necessary, are generated by analyzing the map information. The subgoal is the candidate for the final path to be pass through. Then selection algorithm is executed to choose appropriate subgoal to construct a correct path. Deep and through explanations are given for the proposed algorithm. Simulation example is given to show the effectiveness of the proposed algorithm.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.376-382
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• 2015

Allergic diseases have rapidly increased in recent years. Mast cells play a critical role in IgE-mediated allergy responses and, therefore, closely associated with rhinitis, asthma, and atopic dermatitis. We studied anti-allergic effect of Penthorum chinense extract (PCE) in vitro and in vivo. PCE inhibited the degranulation of mast cells by antigen stimulation and its effect was dose-dependent and reversible in mast cells. PCE also suppressed the production of inflammatory cytokines such as TNF-${\alpha}$ and IL-4 by antigen in mast cells. Mechanistically, PCE inhibited the activation of Syk/LAT pathway which is a key signaling pathway for the activation of mast cells by antigen. Notably, PCE suppressed IgE-mediated allergic responses by antigen in mice. These results strongly suggest that PCE is a potential candidate for anti-allergic treatment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.1
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• pp.59-63
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• 2011

In small-power applications, variable-speed motors having high efficiency and controllability become more dominant than brushed DC motors. BLDC motors with permanent magnets in the rotor and SRMs directed by reluctance torque due to no permanent magnets have been strongly studied as a candidate. Compared to the BLDC motors, SRMs are more suitable for low-cost applications since the magnetic structure is simple, mechanically robust, and cheap due to no additional excitation in the rotor such as copper wire, aluminum, and permanent magnets. In addition, relatively small number of phases in single and two-phase SRMs allows more cost savings with regards to material in the motor and switching devices in the converter. In this paper, several 2 phase SRMs are compared to a 3 phase 6/4 SRM in terms of flux distribution in key parts of the motors.

• Journal of Korea Multimedia Society
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• v.8 no.1
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• pp.101-110
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• 2005

Recently software keyboard is widely used in mobile devices where restrictive hardware keyboard is available. In this paper, new software-driven keyboard input method is proposed, which use minimum number of keyboard input with small keyboard space generated after analyzing of database. In this software keyboard is generated dynamically at each input step by analyzing all possible input words. Software keyboard, only possible key buttons are displayed for minimizing keyboard space and preventing mistyping. And it also provide input word completion function when the number of the candidate words is within threshold scope.

• Journal of Positioning, Navigation, and Timing
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• v.8 no.4
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• pp.139-152
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• 2019

The design of new navigation signals is a key factor in building new satellite navigation systems and/or modernizing existing legacy systems. Navigation signal design involves selecting candidate groups and evaluating and analyzing their signal performances. This process can be easily performed through software simulation especially at the beginning of the development phase. The analytical signal performance analysis software introduced in this study is implemented based on equations between the signal design parameters of Radio Navigation Satellite Service (RNSS) and the navigation signal figures-of-merit (FoMs). Therefore, this study briefly summarizes the RNSS signal design parameters and FoMs before introducing the developed software. After that, we explain the operating sequence of the implemented software including the Graphical User Interface (GUI), and calculate the FoMs of an example scenario to verify the feasibility of the software operations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1802-1819
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• 2017

Correlation-enhanced collision attack has been proposed by Moradi et al. for several years. However, in practical operations, this method costs lots of time on trace acquisition, storage and averaging due to its bytewise collision detection. In this paper, we propose a bitwise collision attack based on second-order distance model. In this method, only 9 average traces are enough to finish a collision attack. Furthermore, two candidate models are given in this study to distinguish collisions, and the corresponding practical experiments are also performed. The experimental results indicate that the operation time of our attack is only 8% of that of correlation-enhanced collision attack, when the two success rates are both above 0.9.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1350-1352
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• 2008

Research on down conversion phosphor materials is the key for the development of solid state lighting (SSL). Especially finding alternative red phosphor for white LEDs based on blue or NUV LEDs are important research task. Under this view, we have synthesized a series of $Eu^{3+}$ substituted $La_2W_{2-x}Mo_xO_9$ (x = 0 ~ 2, insteps of 0.1) red phosphor and characterized by X-ray diffraction (XRD) and photoluminescence. XRD results reveal a phase transition from triclinic to cubic structure for $x\;{\geq}\;0$. All the compositions show broad charge transfer band due to charge transfer from oxygen to tungsten/molybdenum and red emission due to $Eu^{3+}$ ions. Select compositions show high red emission intensity compared to the commercial red phosphor under NUV/blue ray excitation. Hence, this candidate can be possible red emitting phosphors for white LEDs.

• Archives of Reconstructive Microsurgery
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• v.20 no.1
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• pp.57-59
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• 2011

Tongue reconstruction after oncologic resection with free flap is important to conserve function and shape. Vertical rectus myocutaneous free flap is usually used for total tongue reconstruction, but our patient was thin and primary closure after flap elevation seemed hard. So we used anterolateral thigh free flap to reduce donor site morbidity and to maintain bulk of the tongue as much as possible. Deepithelization of both middle side of flap and folding was done to mimic normal tongue base's shape and volume. Flap survived without complication and patient underwent concurrent chemoradiation therapy three weeks after surgery. Anterolateral thigh free flap can be good candidate for total tongue reconstruction especially in thin patient.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.144-152
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• 2017

Among the technologies for implementing autonomous vehicles, advanced driver assistance system is a key technology to support driver's safe driving. In the technology using the vision sensor having a high utility, various preprocessing methods are used prior to feature extraction for lane detection. However, in the existing methods, the unnecessary lane candidates such as cars, lawns, and road separator in the road area are false positive. In addition, there are cases where the lane candidate itself can not be extracted in the area under the overpass, the lane within the dark shadow, the center lane of yellow, and weak lane. In this paper, we propose an efficient preprocessing method using k-means clustering for image division and the HSV color model. When the proposed preprocessing method is applied, the true positive region is maximally maintained during the lane detection and many false positive regions are removed.

• Journal of Crop Science and Biotechnology
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• v.10 no.3
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• pp.123-132
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• 2007

In this review, we discuss the ways in which our understanding of the controls of nitrogen use efficiency applied to crop improvement has been increased through the development of molecular physiology studies using transgenic plants or mutants with modified capacities for nitrogen uptake, assimilation and recycling. More recently, exploiting crop genetic variability through quantitative trait loci and candidate gene detection has opened new perspectives toward the identification of key structural or regulatory elements involved in the control of nitrogen metabolism for improving crop productivity. All together these studies strongly suggest that in the near future nitrogen use efficiency can be improved both by marker-assisted selection and genetic engineering, thus having the most promise for the practical application of increasing the capacity of a wide range of economically important species to take up and utilize nitrogen more efficiently.