• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.8
• /
• pp.225-231
• /
• 2013

Medical image segmentation is an image processing technology prior to performing various medical image processing. Therefore, a variety of methods have been researched for fast and accurate medical image segmentation. Accurate judgment of segmentation region is needed to segment the interest region in which patient requested in medical image that various organs exist. However, an case that scanned a part of organs is small occurs. In this case, information to determine the segmentation region is lack. consequently, a removal of segmentation region occurs during the segmentation process. In this paper, we improved segmentation results in a small region using volume data and linear equation. In order to verify the performance of the proposed method, we segmented the lung region of chest CT images. As a result of experiments, we confirmed that image segmentation accuracy rose from 0.978 to 0.981 and standard deviation also improved from 0.281 to 0.187.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.2
• /
• pp.149-156
• /
• 2018

Now RC cars have become a culture where everyone who wants to feel precise control and rushing instinct regardless of sex, young or old can participate. In addition, RC cars have attracted a lot of people because they can feel the feeling of driving while driving a car in a small, lightweight body. In line with these trends, various development companies are focusing on functional aspects such as driving and speed improvement for each environment and their sophistication. Of course, driving performance alone can bring a tremendous ripple effect, but what you can do with a RC car is only part replacement and motor modification. Therefore, we will develop RC car based on raspberry pie, control by application, add various functions through sensor recognition, and develop RC car that can travel through video information that can be obtained using web cam. As a small RC car, we carry out research that can combine the functions that can be used as a robot that moves at various construction sites and accident sites where people can not enter, and which can attract users' interest.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.1
• /
• pp.63-69
• /
• 2017

In this paper, we propose a method to optimize the geometry and installation position of the mixer in the selective catalytic reduction (SCR) system by computational fluid dynamic(CFD). Using the commercial CFD software of CFD-ACE+, the flow dynamics of the flue gas was numerically analyzed for improving the injection uniformity of the reduction agent. Numerical analysis of the mixed gas heat flow into the upstream side of the primary SCR catalyst layer was performed when the denitrification facility was operated. The characteristics such as the flow rate, temperature, pressure loss and ammonia concentration of the mixed gas consisting of the flue gas and the ammonia reducing gas were examined at the upstream of the catalyst layer of SCR. The temperature difference on the surface of the catalyst layer is very small compared to the flow rate of the exhaust gas, and the temperature difference caused by the reducing gas hardly occurs because the flow rate of the reducing gas is very small. When the mixed gas is introduced into the SCR reactor, there is a slight tendency toward one wall. When the gas passes through the catalyst layer having a large pressure loss, the flow angle of the exhaust gas changes because the direction of the exhaust gas changes toward a smaller flow. Based on the uniformity of the flow rate of the mixed gas calculated at the SCR, it is judged that the position of the test port reflected in the design is proper.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1945-1948
• /
• 2004

This paper describes the design and construction of a micro robotic system addressing such important aspects as versatility and low cost for rapid development and test of new control algorithm. The design and structure of micro robots are presented in detail. The supervision oriented concept is designed for controlling a group of micro robots. In this concept, the vision system recognizes the environment and the host computer decides the micro robot action based on the information from the vision system. In addition, the micro robots can be implemented cheaply and small in size because the structure of supervision oriented system is simplest. The experimental results and the performance of the proposed micro robotic system are discussed.

• The Journal of Korea Robotics Society
• /
• v.12 no.3
• /
• pp.313-321
• /
• 2017

One of the most frequently performed tasks in human-robot interaction (HRI), intelligent vehicles, and security systems is face related applications such as face recognition, facial expression recognition, driver state monitoring, and gaze estimation. In these applications, accurate head pose estimation is an important issue. However, conventional methods have been lacking in accuracy, robustness or processing speed in practical use. In this paper, we propose a novel method for estimating head pose with a monocular camera. The proposed algorithm is based on a deep neural network for multi-task learning using a small grayscale image. This network jointly detects multi-view faces and estimates head pose in hard environmental conditions such as illumination change and large pose change. The proposed framework quantitatively and qualitatively outperforms the state-of-the-art method with an average head pose mean error of less than $4.5^{\circ}$ in real-time.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.816-821
• /
• 2005

The cycloid reducer has very high efficiency, high ratios, high stiffness and small size, in comparison with a conventional gear mechanism, which makes it an attractive candidate for limited space and precision application such as industrial robot. There are several publications on analysis and design of the cycloid reducer, however, it was assumed that the contact stiffness of pin rollers and cycloid disk is constant regardless of their contact geometry. Moreover, the torsional stiffness of the cycloid reducer couldn't be calculated due to the assumption. In this paper, we present a new procedure of calculating torsional stiffness of the cycloid reducer using Hertz contact theory. First, conventional force analysis of the cycloid reducer is briefly reviewed. Then, iterative numerical calculation procedure of the contact stiffness is proposed based on the Hertz contact theory where the contact stiffness depends on the contact force. In addition, total torsional stiffness of the cycloid reducer is estimated considering its rolling element bearing stiffness. The torsional stiffness of the cycloid reducer is dominated by the rolling element bearing stiffness since the contact stiffness of the cycloid disk is too large.

• Journal of Institute of Control, Robotics and Systems
• /
• v.2 no.4
• /
• pp.279-286
• /
• 1996

In this paper, variable structure control(VSC) based on reaching law method with fuzzy inference for nonlinear systems is proposed. The reaching law means the reaching condition which forces an initial state of system to reach switching surface in finite time, and specifies the dynamics of a desired switching function. Since the conventional reaching law has fixed coefficients, the chattering can be existed largely in sliding mode. In the design of a proposed fuzzy reaching law, we fuzzify RP(representative point)'s orthogonal distance to switching surface and RP's distance the origin of the 2-dimensional space whose coordinates are the error and the error rate. The coefficients of the reaching law are varied appropriately by the fuzzy inference. Hence the state of system in reaching mode reaches fastly switching surface by the large values of reaching coefficients and the chattering is reduced in sliding mode by the small values of those. And the effectiveness of the proposed fuzzy reaching law method is showen by the simulation results of the control of a two link robot manipulator.

• Journal of the Speleological Society of Korea
• /
• no.85
• /
• pp.28-34
• /
• 2008

For trying to frontal attack of new solution by fusion of technical tasks and conditions with it's solving methods of the essential tasks of marine resource development and environmental conservation in addition with elements of electronic high-technologies, the magnetic oil spill adsorbent of Mag-Sorbent* has been prepared and proposed to dispose oil spill from the marine disaster for preventing oil pollution by using them and their system with sequentially circular collection of oil spill mag-sorbent powder and fabrics on the electronic equipment like as barge robot for the scheme of sustainable development of environment-friendly technology. Because of recent marine accident occurred at Tae-An cost and earthquake in Sichuan province were very large scale accident of disaster to prevent and manage of them. So, it was verified from the experiment of electronic demonstrator that the skimmer system of oil spill mag-sorbent powder and fabrics prepared was very effective and useful technique to collect oil spill samples on the water surface specially at the closed space of underground cave. At this point, the barge-based electronic remote control was very useful system operating easily on the marine fields but also water level at the small pool to skim it with the environment-friendly system of the disposing marine disaster and preventing oil pollution using magnetic adsorbents of Mag-Sorbent*.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.8
• /
• pp.823-831
• /
• 2008

Since it needs the light computational load and small database, sound source localization method using time delay of arrival(TDOA method) is applied at many research fields such as a robot auditory system, teleconferencing and so on. Researches for time delay estimation, which is the most important thing of TDOA method, had been studied broadly. However studies about factors for time delay estimation are insufficient, especially in case of real environment application. In 1997, Brandstein and Silverman announced that performance of time delay estimation deteriorates as reverberant time of room increases. Even though reverberant time of room is same, performance of estimation is different as the specific part of signals. In order to know that reason, we studied and analyzed the factors for time delay estimation using speech signal and room impulse response. In result, we can know that performance of time delay estimation is changed by different R/D ratio and signal characteristics in spite of same reverberant time. Also, we define the performance index(PI) to show a similar tendency to R/D ratio, and propose the method to improve the performance of time delay estimation with PI.

• Proceedings of the KIEE Conference
• /
• 2001.11c
• /
• pp.311-314
• /
• 2001

The objectives of this paper include the development of an agile prototype of SFFS, the $CAFL^{VM}$(Computer Aided fabrication of Lamination for Various Material), which is suitable for the multi-item and small-quantity production and various material fabrication. This paper includes remodeling of the layer slices for the 2D cutting, supplementing information of the layer slices and developing process conditions to fabricate products of various shape. And also includes developing control hardware as well as software by enhancing BOF of the manipulator to 3 degree for the precise 2D cutting. It will generate optimal layer trajectory considering the dynamic characteristics of the laser beam. The system can be used as a competitive agile protype system in terms of various materials, fabrication speed, and accuracy by CAD modeling precise layer slicing, material development, robot path control, and optimization of the support structure.