• Journal of Institute of Control, Robotics and Systems
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• v.22 no.9
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• pp.745-752
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• 2016

We suggest an efficient Simultaneous Localization and 3D Polygon Map Building (SLAM) method with Kinect depth sensor for mobile robots in indoor environments. In this method, Kinect depth data is separated into row planes so that scan line segments are on each row plane. After grouping all scan line segments from all row planes into line groups, a set of 3D Scan polygons are fitted from each line group. A map matching algorithm then figures out pairs of scan polygons and existing map polygons in 3D, and localization is performed to record correct pose of the mobile robot. For 3D map-building, each 3D map polygon is created or updated by merging each matched 3D scan polygon, which considers scan and map edges efficiently. The validity of the proposed 3D SLAM algorithm is revealed via experiments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.3
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• pp.513-518
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• 2016

This paper presents a fast 3D mesh generation method using projection for line laser-based 3D scanners. The well-known method for 3D mesh generation utilizes convex hulls for 4D vertices that is converted from the input 3D vertices. This 3D mesh generation for a large set of vertices requires a lot of time. To overcome this problem, the proposed method takes (${\theta}-y$) 2D depth map into account. The 2D depth map is a projection version of 3D data with a form of (${\theta}$, y, z) which are intermediately acquired by line laser-based 3D scanners. Thus, our 2D-based method is a very fast 3D mesh generation method. To evaluate our method, we conduct experiments with intermediate 3D vertex data from line-laser scanners. Experimental results show that the proposed method is superior to the existing method in terms of mesh generation speed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.97-102
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• 1985

A new microwave transmission line frequency discriminator in MIC is described, which is composed of a branch-line hybrid 3dB coupler, a λ/2-short stub and a λ/4-opcn stub. It is experimentally verified that the discriminator is linear in a 400 MHz bandwidth at center frequency 4.94 GHz and has return loss more than 15dB in that range.

• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.300-309
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• 2016

This paper proposes a method for motion estimation of consecutive cameras using 3-D straight lines. The motion estimation algorithm uses two non-parallel 3-D line correspondences to quickly establish an initial guess for the relative pose of adjacent frames, which requires less correspondences than that of current approaches requiring three correspondences when using 3-D points or 3-D planes. The estimated motion is further refined by a nonlinear optimization technique with inlier correspondences for higher accuracy. Since there is no dominant line representation in 3-D space, we simulate two line representations, which can be thought as mainly adopted methods in the field, and verify one as the best choice from the simulation results. We also propose a simple but effective 3-D line fitting algorithm considering the fact that the variance arises in the projective directions thus can be reduced to 2-D fitting problem. We provide experimental results of the proposed motion estimation system comparing with state-of-the-art algorithms using an open benchmark dataset.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1536-1543
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• 2004

Garment is made by a 2D pattern and should be fitted to a human body which has 3D characteristics. Therefore, to design a pattern more effectively, the use of 3D information of a human body and the investigation of relationship between the 3D garment and 2D pattern are necessary. In this work, ruled surface method was used to reflect the 3D information of a human body for a pattern design. The images of the brassiere line on the woman's dress form were captured by phase-shifting projection moire system and the 3D information on the design line was obtained. 2D patterns on the various parts of the brassiere were developed directly from the 3D data by the ruled surface method. In addition, design line, the area and the amount of dart were quantified. And then we verify the appropriateness of the ruled surface method to the 2D pattern development by measuring the distribution of the space between women's figure and segmented clothing item. It was found that the ruled surface method is useful to transform the 3D design line to the 2D pattern, if we followed the steps suggested in this paper.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.4
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• pp.277-285
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• 2004

We present a new hybrid stereo matching technique in terms of the co-operation of area-based stereo and feature-based stereo. The core of our technique is that feature matching is carried out by the reference of the disparity evaluated by area-based stereo. Since the reference of the disparity can significantly reduce the number of feature matching combinations, feature matching error can be drastically minimized. One requirement of the disparity to be referenced is that it should be reliable to be used in feature matching. To measure the reliability of the disparity, in this paper, we employ the self-consistency of the disunity Our suggested technique is applied to the detection of 3D line segments by 2D line matching using our hybrid stereo matching, which can be efficiently utilized in the generation of the rooftop model from urban imagery. We carry out the experiments on our hybrid stereo matching scheme. We generate synthetic images by photo-realistic simulation on Avenches data set of Ascona aerial images. Experimental results indicate that the extracted 3D line segments have an average error of 0.5m and verify our proposed scheme. In order to apply our method to the generation of 3D model in urban imagery, we carry out Preliminary experiments for rooftop generation. Since occlusions are occurred around the outlines of buildings, we experimentally suggested multi-image hybrid stereo system, based on the fusion of 3D line segments. In terms of the simple domain-specific 3D grouping scheme, we notice that an accurate 3D rooftop model can be generated. In this context, we expect that an extended 3D grouping scheme using our hybrid technique can be efficiently applied to the construction of 3D models with more general types of building rooftops.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.7
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• pp.774-783
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• 2012

In this paper, a periodically corrugated transmission line is proposed. The proposed transmission line can reduce crosstalk between transmission lines. The corrugated transmission line can adjust the amount of inductive coupling and capacitive coupling equally. Thus, the crosstalk is effectively reduced because the inductive coupling and capacitive coupling cancel each other. The corrugated transmission line is fabricated on RO4003 substrate with a dielectric constant of 3.38 and a thickness of 0.508 mm. The simulated far-end crosstalks of conventional transmission line and corrugated transmission line with a period of A=1 mm have maximum values of -3.6 dB and -22 dB, respectively, up to 30 GHz. Measurement results showed that far-end crosstalks of the conventional and corrugated transmission line have maximum values of -6.3 dB and -20.5 dB, respectively, up to 30 GHz.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1731-1734
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• 2003

We propose a unmaned integrating control system based-on Windows XP version Off-Line Programming System which can simulate a Robot model in 3D Graphics space in this paper. The robot with 4 and 6 axes modeled SM5 and AM1 respectively were adopted as an objective model. Forward kinematics, inverse kinematics and robot dynamics modeling were included in the developed off-line program. The interface between users and the off-line programming system in the Windows XP's graphic user interface environment was also studied. The developing language is Microsoft Visual C++. Graphic libraries, OpenGL, by silicon Graphics, Inc. were utilized for 3D Graphics.

• Journal of Fashion Business
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• v.24 no.5
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• pp.106-124
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• 2020

The purpose of this study was to analyze the three-dimensional (3D) characteristics and reproducibility of the effective expression of North American smocking pleats in the process of making clothes using a 3D virtual clothing system (CLO) and present a method of expression according to the types of North American smocking. In this study, lattice, lozenge, and flower smocking were produced as real smocking and 3D virtual content, and actual muslin properties were measured using a Fabric Kit and reflected using an emulator. The results of this study confirmed that a dense puckered design such as North American smocking could be expressed depending upon the internal line, fold angle, and reinforcement setting for 3D smocking. To partially apply pleats to flat fabrics, it was necessary to set fold lines. The fold line setting could be expressed by designing the internal line in horizontal, vertical, and diagonal directions according to the North American smocking design, and then setting the fold angle for each internal line. By setting fold angles of 0 degrees and 360 degrees according to the folding direction of the set internal line, the fabric was clearly folded and stable pleats were created. This study will contribute to the vitalization of the 3D virtual fashion content industry by analyzing and presenting the optimal expression method of sophisticated and complex pleats generated according to the North American smocking design pattern.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2339-2344
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• 2014

of a microstrip transmission line, this transmission line can operate as the microstrip line or the coplanar line according to open or short connection between the ungrounded copper plane and grounded plane on the base plane. Two different type operation of the transmission line means that one transmission line can have two different characteristic impedances. This paper proposes and fabricates the circuit to be operated 2-ports power transmission line or 2-way power divider with the stable input matching characteristic by using this dual-impedance transmission line. The proposed circuit operates 2-ports power transmission line in case of the coplanar line or 2-way power divider line in case of the microstrip line. The fabricated circuit shows $S_{21}$ > -0.2 dB and $S_{11}$ < -15 dB above 700 MHz when the circuit operates 2-ports power transmission line. And, it is $S_{21}$ > -3.8 dB, $S_{11}$ < -10 dB and $S_{21}/S_{31}$ < ${\pm}0.3dB$ above 700 MHz when the circuit operates 2-way power divider.