• Journal of the Korea Computer Industry Society
• /
• v.9 no.3
• /
• pp.105-114
• /
• 2008

We present an eye tracking system using a low cost 3D CMOS imager for 3D displays that ensures a correct auto stereoscopic view of position- dependent stereoscopic 3D images. The tracker is capable of segmenting the foreground objects (viewer) from background objects using their relative distance from the camera. The tracker is a novel 3D CMOS Image Sensor based on Time of Flight (TOF) principle using innovating photon gating techniques. The basic feature incorporates real time depth imaging by capturing the shape of a light-pulse front as it is reflected from a three dimensional object. The basic architecture and main building blocks of a real time depth CMOS pixel are described. For this application, we use a stereoscopic type of display using parallax barrier elements that is described as well.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.2
• /
• pp.969-980
• /
• 2018

This paper aims to design of the neutrosophic fuzzy-PID controller and it has been compared with the conventional fuzzy-PID controller for position tracking control in terms of robustness. In the neutrosophic fuzzy-PID controller, error (e) and change of error (ce) were assessed separately on two fuzzy inference systems (FISs). In this study, the designed method is different from the conventional fuzzy logic controller design, membership degrees of antecedent variables were determined by using the T(true), I(indeterminacy), and F(false) membership functions. These membership functions are grouped on the universe of discourse with the neutrosophic set approach. These methods were tested on three-dimensional (3-D) position-tracking control application of a spherical robot manipulator in the MATLAB Simulink. In all tests, reference trajectory was defined for movements of all axes of the robot manipulator. According to the results of the study, when the moment of inertia of the rotor is changed, less overshoot ratio and less oscillation are obtained in the neutrosophic fuzzy-PID controller. Thus, our suggested method is seen to be more robust than the fuzzy-PID controllers.

• Journal of KIBIM
• /
• v.5 no.2
• /
• pp.46-54
• /
• 2015

Vision-based tracking has been proposed as a means to efficiently track a large number of construction resources operating in a congested site. In order to obtain 3D coordinates of an object, it is necessary to employ stereo-vision theories. Detecting and tracking of multiple objects require an entity matching process that finds corresponding pairs of detected entities across the two camera views. This paper proposes an efficient way of entity matching for tracking of construction workers. The proposed method basically uses epipolar geometry which represents the relationship between the two fixed cameras. Each pixel coordinate in a camera view is projected onto the other camera view as an epipolar line. The proposed method finds the matching pair of a worker entity by comparing the proximity of the all detected entities in the other view to the epipolar line. Experimental results demonstrate its suitability for automated entity matching for 3D vision-based tracking of construction workers.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.70.1-70
• /
• 2001

Recently, research of visual control is getting more essential in robotic application, and acquiring 3D informations from the 2D images is becoming more important with development of vision system. For this application, we propose the effective way of controlling stereo vision tracking system for target tracking and calculating distance between target and camera. In this paper we address improved controller using dual-loop visual servo which is more effective compared with using single-loop visual servo for stereo vision tracking system. The speed and the accuracy for realizing a real time tracking are important. However, the vision processing speed is too slow to track object in real time by using only vision feedback data. So we use another feedback data from controller parts which offer state feedback ...

• Journal of Satellite, Information and Communications
• /
• v.5 no.2
• /
• pp.82-86
• /
• 2010

In this paper, a power amplifier module for WCDMA base-station applications is designed and implemented using GaN field-effect transistors (FETs), which uses an envelope tracking bias system. The designed module consists of an high gain MMIC amplifier, a driver amplifier, a power amplifier, and bias circuits for envelope tracking applications. Especially, a FET bias sequencing circuit and two isolators are integrated for stable RF operations. All circuits are assembled within a single housing, so its dimension is just $17.8{\times}9.8{\times}2.0\;cm3$. Measured results show that the developed power amplifier module has good envelope tracking capability: the power-added efficiency of 35% at the output power range from 30dBm to 40dBm over a wide range of drain bias.

• The Journal of Korean Society for Radiation Therapy
• /
• v.30 no.1_2
• /
• pp.73-81
• /
• 2018

Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

• Proceedings of the KSME Conference
• /
• 2004.11a
• /
• pp.1574-1579
• /
• 2004

A simultaneous measurement system that can analyze the flow-structure interactions(FSI) has been constructed and analyses on the flow field and the motion field of a floating cylinder was made. The three-dimensional vector fields around the cylinder are measured by 3D-PTV technique while the motion of the cylinder forced by the flow field is measured simultaneously with a newly developed motion tracking algorithm(bidirectional tracking algorithm). The cylinder is pendant in the working fluid of a water channel and the surface of the working fluid is forced sinusoidal to make the cylinder bounced. The interaction between the flow fields and the cylinder motion is examined quantitatively.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.35 no.2
• /
• pp.128-133
• /
• 2015

This paper describes the construction of a static 3D ultrasonography image by tracking the radiation beam position during the handy operation of a 1D array probe to enable point-of-care use. The theoretical model of the transformation from the translational and rotational information of the sensor mounted on the probe to the reference Cartesian coordinate system was given. The signal amplification and serial communication interface module was made using a commercially available sensor. A test phantom was also made using silicone putty in a donut shape. During the movement of the hand-held probe, B-mode movie and sensor signals were recorded. B-mode images were periodically selected from the movie, and the gray levels of the pixels for each image were converted to the gray levels of 3D voxels. 3D and 2D images of arbitrary cross-section of the B-mode type were also constructed from the voxel data, and agreed well with the shape of the test phantom.

• Journal of information and communication convergence engineering
• /
• v.6 no.3
• /
• pp.331-336
• /
• 2008

In this paper, we propose a real-time people tracking system with multiple CCD cameras for security inside the building. To achieve this goal, we present a method for 3D walking human tracking based on the IMPRESARIO framework incorporating cascaded classifiers into hypothesis evaluation. The efficiency of adaptive selection of cascaded classifiers has been also presented. The camera is mounted from the ceiling of the laboratory so that the image data of the passing people are fully overlapped. The implemented system recognizes people movement along various directions. To track people even when their images are partially overlapped, the proposed system estimates and tracks a bounding box enclosing each person in the tracking region. The approximated convex hull of each individual in the tracking area is obtained to provide more accurate tracking information. We have shown the improvement of reliability for likelihood calculation by using cascaded classifiers. Experimental results show that the proposed method can smoothly and effectively detect and track walking humans through environments such as dense forests.

• KIPS Transactions on Software and Data Engineering
• /
• v.4 no.12
• /
• pp.585-588
• /
• 2015

The technical challenge of 3D image display using the wireless sensor were applied to variable areas and scopes. This techniques need to very accurate location and speed informations and recognitions to moving objects. The tracking challenges of the moving objects location that combined 3D location and speed sensor were applied to sports and healthcare areas. This areas seek to the accuracy and collections and tightly related to image display and analysis techniques. In this paper, We developed the 3D motion display that can be monitor moving objects on the 3D virtual space. For this works, we constructed the database that collected informations through 9-axis sensor and demonstrated the result of 3D motion display on the Window based environments.