Earticle

본 논문에서는 사물인터넷(IoT, Internet of Things) 사용자가 안드로이드 플랫폼 기반의 홈 허브가 유니티 3D 모델링으로 사물인터넷 센서의 3D 위치표출 방안이 제안되었다. 특별히, 3차원 공간에서 IoT 센서는 설치 공간별로 클러스링을 통해 IoT센서 속성과배터리 상태를 모니터링 방식을 설계한다. 또한, 3차원 공간상에서 신규 설치한 IoT 센서가 인접 센서들의 무선신호의 비콘신호및 도착시간 분석에 따른 센서의 위치를 추적하는 방식은 센서의 무선신호세기(RSSI, received signal strength indicator)와 방위각을 기반으로 3차원 공간상에서 수신 각도에 따른 센서의 3D 위치를 표출할 수 있다. 이때 유니티 런쳐가 탑재된 스마트 허브 플랫폼은 사물인터넷 센서의 동작상태 모니터링이 가능하며, 다양한 센서의 생애주기를 관리할 수 있도록 동영상이 3차원 텍스쳐가 동시에연동하도록 활용할 수 있다.

In this paper, the 3D positioning of IoT sensors with the Unity engine of android platform based home-hub was proposdefor IoT(Internet of Things) users. Especially, the monitoring of IoT sensor and battery status was designed with the clusteringof IoT sensor's position. The 3D positioning of RSSI(received signal strength indicator) and angle for new IoT sensoraccording to clustering method was described with the cooperation of beacon and received arrival signal time. This unityengine based smart hub platform can monitor the working situation of IoT sensors, and apply 3D video with texture forthe life-cycling of many IoT sensors simultaneously. rs was described with RSSI(received signal strength indicator) and received angle.

손끝은 최고의 촉각 센서이자 최고의 운동 기관이다. 많은 기술자들은 손끝의 감각에 의존하여 그들의 정 확하고 숙련된 솜씨로 결과물을 만들곤 한다. 컴퓨터 게임 역시 섬세한 조작을 요구하는 분야임에도 불구하 고 제작과 구현의 어려움 때문에 대부분의 게임 인터페이스들은 촉각이나 손이 나타내는 복잡한 표현들은 고려하지 않는다. 또한 VR이 빠르게 발전하고 있고 여러 종류의 가상 환경 몰입형 입력 장치들이 나타나고 있지만, 그들의 기술 수준은 게임 패드에 각종 센서가 추가된 정도에 머무르고 있다. 본 논문에서는 손가락 의 위치를 통한 3D 인터페이스를 설계하는 방법론을 소개한다. 전통적으로 손을 인식하는 입력 방식에서는 주로 몇몇 제스쳐와 간단한 표현들을 인식하는데 그쳤으며, 상대적으로 미소한 손가락 관절의 움직임이나 손 과 손 사이의 상호작용 등의 복잡한 제스쳐에 대해서는 전혀 고려하지 못하고 있다. 본 방법론은 이러한 표 현들을 어떻게 구현할 것인지 제시하며, 손가락의 위치나 각도 등 복합적인 데이터를 계산하여 의미 있는 정 보들을 도출해낼 수 있게 한다. 또한 실험을 위해 구현된 간단한 프로그램에서는 구체적으로 어떻게 작동하 는지와 무엇을 표현할 수 있는지 보여준다. 이를 통해 3D와 몰입형 가상 환경에서 손이 나타내는 복잡한 표 현들을 구현하는데 적용될 수 있을 것으로 예상된다.

Fingertip is both the best touch sensor and the finest actuator. Many technicians depend on their touch of fingertips to regenerate accurate and well-experienced actions. Although computer game is also the area that delicate control is needed, most of game interfaces have no such considerations because they can’t represent tactile impression. Furthermore, as VRs are rapidly evolving, various input interfaces for immersive 3D environments are emerging but their technical level remains on the same stage of gamepad with some sensors. This paper proposes a methodology to design 3D interface that uses positions of fingers. In traditional methods hand-tracking devices usually recognize some gestures and simple expressions. However, this kind of methods don’t consider about some complicated gestures which include comparatively minute finger joints movement and interactions between hands. Proposed methodology presents how to apply these expressions to 3D applications. To derive meaningful outputs from these small expressive controls, it contains many computations among finger position vectors, angles, etc. Following simple application using the method shows how it works and what can it express with hands. Although the quality of results and visual output is not so adorable because of some technical obstacles and artless processes, in conclusion it is expected that this method can be applied to implement complicated hands expressions in 3D and also immersive environment.

In this experiment, the error according to the measurement method was analyzed for the length, angle, radius of curvature, and diameter of the measurement system analysis using a profile projector device used in the field. One-way analysis was performed on each data tested 30 times using a statistical technique. Through the experiment, it was found that an error occurred in each data when measuring the angle according to the measurement method, and the null hypothesis that no error occurred when measuring the length, inside dia and radius was established.

FDM 3D Printer is used in maker space for mass production by the maker. Makers desire to manufacture products in a variety of colors using ABS Filaments. The purpose of this study is to identify the relation between the color of resin and each position on the bed. So, when printed using the 3D Printer, we found out the difference in the colors that it appears depending on the position of the bed. To see the difference in color, basic, blue, yellow, white, and black were selected and the bed plate was divided into three sections. Specimens were measured to obtain delta E values between each sections by the chromatic differential system. Obtained delta values were analyzed by the NBS system. As a result, the delta E value of black was found to correspond to “Appreciable”. In most cases, delta E values between the middle and the outer or the inner and the outer was greater than values between the middle and the inner. Using Infrared Thermal Camera, We found that the color difference relates 3D printing positions and temperatures. As a result, the 3D printing bed positions should be considered when 3D printing mass production.

Fused Deposition Modeling (FDM), also known as Fused Deposition Modeling (FFF), is the most widely used type of 3D printing at the consumer level. The FDM 3D printer extracts thermoplastic filaments such as ABS (Acrylonitrile Butadiene Styrene) and Polyactive Acid (PLA) through heated nozzles to dissolve the material. It works by applying layers of plastic to build platforms. Various demands for 3D printers increased, and among these demands, there was also a demand for various filament colors. ABS, one of the main filamentous materials for 3D printers, is easy to color in a variety of colors and has been studied to meet the needs of these users. Through quantitative measurements in this work, we confirm that color differences remain depending on the difference in placement on the 3D printer bad. In addition, the temperature of the specimen was measured at the start of 3D printing, during manufacturing, and at the completion of manufacturing, and the inner and central sides remained similar, but the outer sides were 5 degrees lower. These temperature differences accumulate as layers pile up, resulting in differences in weight or color, which in turn meet consumer and producer needs in the 3D printer industry.

This paper presents a 3D particle position measurement method based on the defocusing concept introduced by A.Pentland with a single camera. Different from the existing approaches, the blur circle is used to identify the blur extent for various defocused particles, and the depth-blur relation is formulated by the modified A.Pentland mathematical formula. And, an eight-step algorithm based on Circular Hough Transform and Quadrant Radius Histogram was given to calculate the 3D particle position. Experiments on real defocused particle images have demonstrated the feasibility of the proposed method for 3D particle position recovery, and the minimum Mean Absolute Error of depth is about 0.18 mm.

많은 사용자가 항상 휴대하는 스마트폰을 대상으로 실내에서의 위치 인식을 위한 기술 개발이 매우 활발하다. 특히 음향 신호를 이용한 TDOA 방식의 위치 측정 시스템도 많이 연구되고 있는데, 이 방식은 스마트폰의 스피커와 음향 신호를 수신하기 위한 위치 측정 장치에 설치된 마이크들 사이의 거리를 측정하고 관련 쌍곡선 수식을 계산하여 스마트폰의 위치를 추정하는 것이다. 그러나 스피커와 각 마이크 사이의 거리를 측정하는 것에 항상 오차가 있고, 게다 가 위치 측정 장치에 설치된 음향 센서인 마이크의 설치 위치 오차에 따라서 위치 측정 오차가 매우 크게 발생한다. 본 논문에서는 3차원 TDOA 위치 측정 시스템에서 음향 센서의 위치 오차에 따른 위치 측정 오차가 PDOP 시뮬레이 션과 실험으로 분석되었다.

Indoor positioning technology has been developed very actively for the smart phone handheld by most users. Especially, many TDOA positioning systems using acoustic signal have been studied, and it estimates the smart phone position by measuring the distance between the smart phone speaker and the microphones which is installed to receive the acoustic signal from the smart phone, and by calculating the hyperbolic equations. But there are always errors for the distance measurements, and furthermore the microphone installation error produces huge position estimation error. In this paper, the position estimation error due to the position error of acoustic sensor in the 3 dimensional TDOA positioning system, is analyzed by PDOP simulation and experiment.

호흡동조방사선치료에서 비동일 평면치료는 테이블의 회전이 있기 때문에 테이블의 회전에 따른 적외선 카메라와 마커 사이의 거리 변화로 인하여 마커 움직임의 인식을 Real-time Position Management 시스템의 two dot 마커와 six dot 마커의 움직임 반영의 정확성을 평가하고자 한다. 움직임을 평가는 two dot 마커에서 테이블 각도를 시계방향, 반시계방향으로 각 $10^{\circ}$씩 변화하여 측정하였으며, six dot 마커에서도 테이블 각도를 시계방향으로 각 $10^{\circ}$ 변화하여 기준 $0^{\circ}$에서의 기준과 비교하였을 때 기준 진폭 1.173에서 1.165, 테이블 각도 $20^{\circ}$에서는 1.132, 테이블 각도 $30^{\circ}$에서는 1.083의 진폭값으로 나타났다. 반시계방향으로 $350^{\circ}$에서는 기준 진폭 1.168에서 1.157, 테이블 각도 $340^{\circ}$에서는 1.124, 테이블 각도 $330^{\circ}$에서는 1.079 진폭값으로 나타났다. 본 연구에서는 팬톰을 이용하여 테이블 변화에 따른 진폭의 값을 정량적으로 평가한 점에 학술적 의미를 두고자 한다.

Because of non-coplanar therapy with couch rotation in respiratory gated radiation therapy, the recognition of marker movement due to the change in the distance between the infrared camera and the marker due to the rotation of the couch is called RPM (Real-time The purpose of this paper is to evaluate the accuracy of motion reflections (baseline changes) of 2D gating configuration (two dot marker block) and 3D gating configuration (six dot marker block). The motion was measured by varying the couch angle in the clockwise and counterclockwise directions by $10^{\circ}$ in the 2D gating configuration. In the 3D gating configuration, the couch angle was changed by $10^{\circ}$ in the clockwise direction and compared with the baseline at the reference $0^{\circ}$. The reference amplitude was 1.173 to 1.165, the couch angle at $20^{\circ}$ was 1.132, and the couch angle at $1.0^{\circ}$ was 1.083. At $350^{\circ}$ counterclockwise, the reference amplitude was 1.168 to 1.157, the couch angle at $340^{\circ}$ was 1.124, and the couch angle at $330^{\circ}$ was 1.079. In this study, the phantom is used to quantitatively evaluate the value of the amplitude according to couch change.

로봇을 비롯한 자동화 기계의 3차원 작업에서 스테레오 카메라는 가장 널리 사용되는 센서 장치이다. 스테레오 카메라를 사용함으로써 3차원 실세계 공간내 임의 목표점의 위치를 측정할 수 있으며, 카메라의 보정은 이를 위한 중요한 선행작업이다. 기존의 카메라 보정법은 크게 선형과 비선형의 기법으로 나눌 수 있는데, 선형의 기법은 간단하나 정확도의 면에서 문제점을 지니고, 비선형 기법은 렌즈의 왜곡을 보상하기 위한 모델링 과정과 이의 비선형 해를 구하는 비교적 복잡한 과정을 필요로 한다는 문제가 있다. 본 논문에서는 이러한 문제의 한 해결방안으로 인공신경망을 적용하는 방법을 연구하고 그 결과를 제시한다. 특히 역전파 알고리즘에 의해 학습된 다층 신경망의 함수 근사화 능력을 활용하여 선형기법의 오차 패턴을 학습함으로써 간단하고 효과적으로 계측의 정확도를 향상시킬 수 있음을 실험을 통하여 보인다.

Stereo cameras are the most widely used sensing systems for automated machines including robots to interact with their three-dimensional(3D) working environments. The position of a target point in the 3D world coordinates can be measured by the use of stereo cameras and the camera calibration is an important preliminary step for the task. Existing camera calibration techniques can be classified into two large categories - linear and nonlinear techniques. While linear techniques are simple but somewhat inaccurate, the nonlinear ones require a modeling process to compensate for the lens distortion and a rather complicated procedure to solve the nonlinear equations. In this paper, a method employing a neural network for the calibration problem is described for tackling the problems arisen when existing techniques are applied and the results are reported. Particularly, it is shown experimentally that by utilizing the function approximation capability of multi-layer neural networks trained by the back-propagation(BP) algorithm to learn the error pattern of a linear technique, the measurement accuracy can be simply and efficiently increased.

In this study, we evaluated the performance of a commercial pixelated cadmium zinc telluride (CZT) detector for spectroscopy and identified its feasibility as a Compton camera for radiation monitoring in a nuclear power plant. The detection system consisted of a $20mm{\times}20mm{\times}5mm$ CZT crystal with $8{\times}8$ pixelated anodes and a common cathode, in addition to an application specific integrated circuit. The performance of the various radioisotopes $^{57}Co$, $^{133}Ba$, $^{22}Na$, and $^{137}Cs$ was evaluated. In general, the amplitude of the induced signal in a CZT crystal depends on the interaction position and material non-uniformity. To minimize this dependency, a drift time correction was applied. The depth of each interaction was calculated by the drift time and the positional dependency of the signal amplitude was corrected based on the depth information. After the correction, the Compton regions of each spectrum were reduced, and energy resolutions of 122 keV, 356 keV, 511 keV, and 662 keV peaks were improved from 13.59%, 9.56%, 6.08%, and 5%-4.61%, 2.94%, 2.08%, and 2.2%, respectively. For the Compton imaging, simulations and experiments using one $^{137}Cs$ source with various angular positions and two $^{137}Cs$ sources were performed. Individual and multiple sources of $^{133}Ba$, $^{22}Na$, and $^{137}Cs$ were also measured. The images were successfully reconstructed by weighted list-mode maximum likelihood expectation maximization method. The angular resolutions and intrinsic efficiency of the $^{137}Cs$ experiments were approximately $7^{\circ}-9^{\circ}$ and $5{\times}10^{-4}-7{\times}10^{-4}$, respectively. The distortions of the source distribution were proportional to the offset angle.

Our goal is the development of a system that estimates the location of interested point in a room with accuracy and low cost. Non-contacting position estimating method is widely used in various areas. Among these methods, acoustic signal-based method is the cheapest and provides reasonably accurate estimation as a result of many research efforts. Most of the acoustic-signal-based three-dimensional location estimators such as 3D sonic digitizer are using the ultrasound, and are organized with two procedures; time-of-flight (TOF) estimation and localization estimation. Since the errors in estimating the TOF could be accumulated with that of localization estimate, accuracy of TOF estimate is as...

This paper introduces a novel approach that can provide the three dimensional information on the movement of a spreader by using two CCD cameras and a laser distance sensor, which enables an ALS (Automatic Landing System) to be used for yard cranes at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as corner detectors for the geometrical matching between the spreader and a container, which provides only 2D information which is not enough for an accurate and fast ALS system required presently. In addition to this deficiency in performance, the price for the system is too high to be adopted widely for the ALS. Therefore, to overcome these defects, a novel method to acquire the three dimensional information for the movement of a spreader including skew and sway angles is proposed using two CCD cameras and a laser distance sensor. To show the efficiency of proposed algorithm, real experiments are performed to show the accuracy improvement in distance measurement by fusing the sensory information of CCD camera and laser distance sensor.

This paper introduces a novel approach that can provide the three dimensional information about the movement of a spreader by using two CCD cameras and a laser distance measuring unit in order to derive ALS (Automatic Landing System) in the crane used at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as comer detectors for the geometrical matching between the spreader and a container. Such systems provide only two dimensional information which is not enough for an accurate and fast ALS. In addition to this deficiency in performance, the price of the system is too high to adapt to the ALS. Therefore, to overcome these defects, we proposed a novel method to acquire the three dimensional spreader information using two CCD cameras and a laser distance measuring unit. To show the efficiency of proposed method, real experiments are performed to show the improvement of accuracy in distance measurement by fusing the sensory information of the CCD cameras and a laser distance measuring unit.

본 논문에서는 기존의 EPS(Electric Power Steering) 시스템에 IPMSM을 적용하고 속도 및 위치를 검출하기 위하여 Magnetic Position Sensor를 사용하였다. 이�� Magnetic Position Sensor의 신호는 정현파의 출력을 갖지만 고조파의 성분으로 인하여서 파형이 왜곡되고 이러한 파형의 왜곡으로 인해 위치 검출의 오차를 갖게 된다. 본 논문에서는 이러한 오차를 줄이기 위하여 다구찌 기법과 3차원 유한요소법(3D FEM)을 사용하여 고조파를 저감시킬 수 있도록 여러 변수를 변화하여서 최적의 설계를 통하여 실제 실제 센서 출력과 비교하여 자동차 산업 전반에 기여 하고자 한다.

Ultrasonic Positioning System (UPS) is an absolute positioning system using ultrasonic waves and has better performance in low price than the other absolute positioning systems. UPS can be further used as pseudo-satellites in the place where GPS is not available. This study aims to evaluate the efficiency and effectiveness of using UPS as a 3D free-hand writing or drawing tool. The process includes the design and testing of VPS as an efficient 3D free-hand writing or drawing tool in the air. The paper will further explain the system architecture of the UPS and how to use GPS as 3D free-hand writing or drawing tool. The efficiency and effectiveness of the system was confirmed by a computer software simulation. The software will further display the result of drawing or writing from the user by graphics. As a result, it is possible to implement UPS as a 3D free-hand writing or drawing tool in the air.

This paper deals with an optimal angle error reduction method of magnetic position sensor using hall effect elements. The angle detection simulation for the magnetic position sensor is performed by 3 dimensional finite element method and Taguchi method, one of the design of experiments. The magnetic position sensor is required to generate ideal sine and cosine waveforms from its hall effect elements according to rotation angle for precise angle information. However, the output signals are easy to include harmonics due to uneven magnetic field distribution from permanent magnet in the air-gap in the vicinity of hall effect elements. For the Taguchi method, three design parameters related to position of hall effect elements and shape of back yoke are selected. The characteristics of optimal magnetic position sensor are compared with those of original one in terms of simulation as well as experiment. Finally, the performances of the motor adopting original model and optimal model are represented for the purpose of verification of motor performance due to signals from magnetic position sensor.

In this paper, we present a method to detect the position of a 3D object in scattering media by using the axially distributed sensing (ADS) method. Due to the scattering noise of the elemental images recorded by the ADS method, we apply a statistical image processing algorithm where the scattering elemental images are converted into scatter-reduced ones. With the scatter-reduced elemental images, we reconstruct the 3D images using the digital reconstruction algorithm based on ray back-projection. The reconstructed images are used for the position detection of a 3D object in the scattering medium. We perform the preliminary experiments and present experimental results.

Recently, autonomous robots which can achieve the complex tasks have been required with the advance of robotics. Advanced robot vision for recognition is necessary for the realization of such robots. In this paper, we propose a method to recognize an object in the actual environment. We assume that a 3D-object model used in our proposal method is the voxel data. Its inside is full up and its surface has color information. We also define the word "recognition" as the estimation of a target object's condition. This condition means the posture and the position of a target object in the actual environment. The proposal method consists of three steps. In Step 1, we extract features from the 3D-object model. In Step 2, we estimate the position of the target object. At last, we estimate the posture of the target object in Step 3. And we experiment in the actual environment. We also confirm the performance of our proposal method from results.

Stereoscopic 3D technology using patterned retarder and eyeglass of circular polarizer shows dependence on the user position and condition of circular polarizer eyeglass. Cause of these dependencies and its effects on the 3D display performances were analyzed.