• International Journal of Internet, Broadcasting and Communication
• /
• v.16 no.4
• /
• pp.255-264
• /
• 2024

Infrared-based scanners are utilized as a promising method for detecting objects that contact on a surface. In this system, infrared transmitters and receivers are positioned at opposite ends of the plane, facing each other. Traditionally, this system employed a one-to-one scanning method, where a single infrared transmitter emits a light signal that is detected by a corresponding receiver on the opposite side. While this method offers advantages such as fast response times and system simplicity, it is limited by its inability to detect multiple objects simultaneously. To address this limitation, recent applications have adopted the one-to-many scanning. In this scanning method, a single infrared transmitter emits a light signal that is detected by multiple receivers on the opposite side. The results are then read in real-time to determine the position and size of the object. With the recent advancements in computing power, the response speed and accuracy of one-to-many scanning have significantly improved. However, in most cases, this method has been limited to object detection on simple planes, and there is no analytical method available to support performance prediction when considering various sensor installation configurations with various form-factors. In this study, we mathematically modeled an infrared sensor array system to predict the performance of various sensor configurations installed on two-dimensional planes or curved surfaces. Additionally, we assess the critical effect of inevitable positional errors (including orientation mismatches) on the system's performance. The unique approach introduced in this paper will provide highly reliable quantitative predictions, aiding in the design of sensor network form factors tailored for various applications in the future.

• Proceedings of the Korea Association of Crystal Growth Conference
• /
• 1996.06a
• /
• pp.258-292
• /
• 1996

In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.540-546
• /
• 2008

In the near future, robots should be able to understand human's emotional states and exhibit appropriate behaviors accordingly. In Human-Human Interaction, the 93% consist of the speaker's nonverbal communicative behavior. Bodily movements provide information of the quantity of emotion. Latest personal robots can interact with human using multi-modality such as facial expression, gesture, LED, sound, sensors and so on. However, a posture needs a position and an orientation only and in facial expression or gesture, movements are involved. Verbal, vocal, musical, color expressions need time information. Because synchronization among multi-modalities is a key problem, emotion expression needs a systematic approach. On the other hand, at low intensity of surprise, the face could be expressed but the gesture could not be expressed because a gesture is not linear. It is need to decide the emotional boundaries for effective robot behavior generation and synchronization with another expressible method. If it is so, how can we define emotional boundaries? And how can multi-modality be synchronized each other?

• Korean Journal of Remote Sensing
• /
• v.36 no.5_4
• /
• pp.1221-1229
• /
• 2020

In urgent situations such as disasters and accidents, rapid data acquisition and processing is required. Therefore, in this study, a rapid geocoding method according to EOP (Exterior Orientation Parameter) correction was proposed through pattern analysis of the initial UAV image information. As a result, in the research area with a total flight length of 1.3 km and a width of 0.102 ㎢, the generation time of geocoding images took about 5 to 10 seconds per image, showing a position error of about 8.51 m. It is believed that the use of the rapid geocoding method proposed in this study will help provide basic data for on-site monitoring and decision-making in emergency situations such as disasters and accidents.

• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2005.11a
• /
• pp.55-60
• /
• 2005

Ubiquitous computing environment means the computing environment that has taken its position so closely with the ordinary living so much like air or water. In building up the U-Korea, one of the important issues is the social issue from the drastic increase of senior population. The contemporary society has its distinct trend in increase of senior household following the nuclear family orientation, increase of working parents with the advancement of women in society, unable to support seniors for long distance or short distance of business trip and other reasons that the need of senior welfare has been ever more felt. Accordingly, the Ministry of Government Affairs and Home Administration has developed the wireless paging system to make prompt response system for 119 Rescue when the single senior is encountered with emergency situation that is has been widely provided for the socially neglected people such as single senior, the disabled persons and others. Currently, the wireless paging system is operated as the sub-system for emergency rescue information system, but due to the lack of reliability of product, problems of terminal portable transmitter, receptor and others, rejection of beneficiary and lack of knowledge in use, insufficient management and supervision of managing officers, the efficiency has been declined that there is a need of development for the system. Therefore, this study proposes the context aware information structure of the subject of ubiquitous wireless paging system required for the development of the wireless paging system model of ubiquitous environment that improved the problems of currently operated wireless paging system.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.6
• /
• pp.899-905
• /
• 2013

In this paper, we focus on how to calibrate multi-cameras easily and how to efficiently detect quad-copters with small-numbered particles. Each particle is a six dimensional vector that is composed of 3D position and 3D orientation of a quad-copter in the space. Due to curse of dimensionality, that leads to explosive computational costs with a large amount of high-dimensioned particles. To detect efficiently, we need to put more particles in very promising spaces and few particles in other spaces. Though computational cost is lowered by minimizing particles, in order to track a quad-copter with multiple cameras in real-time, multiple images from the cameras should be synchronized and analyzed. Therefore, lots of the computations still need to be done. Because of this, GPGPU(General-Purpose computing on Graphics Processing Units) is implemented for parallel computing. This method has been successfully tested and gives accurate results in practical situations.

• Korean Journal of Materials Research
• /
• v.13 no.7
• /
• pp.478-483
• /
• 2003

The crystallographic characteristics of the $(Bi, La)_4$$Ti_3$$O_{12}$ thin film, which is considered as an applicable dielectrics in the ferroelectric RAM device due to a low crystallization temperature and a good fatigue property, were investigated at the atomic scale by high resolution transmission electron microscopy and the high resolution Z-contrast technique. The analysis showed that a (00c) preferred orientation and a crystallization of the film were enhanced with the diffraction intensity increase of the (006) and (008) plane as the annealing temperature increased. It indicated a change of the atomic arrangement in the (00c) plane. Stacking faults on the (00c) plane were also observed. Through the comparison of the high-resolution Z-contrast image and the $Bi_4$$Ti_3$$O_{12}$ atomic model, it was evaluated that the intensity of the Bi atom was different according to the atomic plane, and it was attributed to a substitution of La atom for Bi at the specific atom position.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.9 no.2
• /
• pp.129-135
• /
• 2015

The objective grading system for the facial palsy is needed. In this study, the facial palsy grading system was developed with combination of three dimensional image processing and Nottingham scale. The developed system is composed of 4 parts; measurement part, image processing part, computational part, facial palsy evaluation & display part. Two web cam were used to get images. The 8 marker on face were recognized at image processing part. The absolute three dimensional positions of markers were calculated at computational part. Finally, Nottingham scale was calculated and displayed at facial palsy evaluation & display part. The effects of measurement method and position of subject on Nottingham scale were tested. The markers were measured with 2-dimension and 3-dimension. The subject was look at the camera with $0^{\circ}$ and $11^{\circ}$ rotation. The change of Scale was large in the case of $11^{\circ}$ rotation with 2-dimension measurement. So, the developed system with 3-dimension measurement is robust to the orientation change of subject. The developed system showed the robustness of grading error originated from subject posture.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.49 no.4
• /
• pp.23-35
• /
• 2012

This paper presents a 3-D pose (position and orientation) estimation method for an elliptic object in 3-D space. It is difficult to resolve the problem of determining 3-D pose parameters with respect to an elliptic feature in 3-D space by interpretation of its projected feature onto an image plane. As an alternative, we propose a two points-based pose estimation algorithm to seek the 3-D information of an elliptic feature. The proposed algorithm determines a homogeneous transformation uniquely for a given correspondence set of an ellipse and two coplanar points that are defined on model and image plane, respectively. For each plane, two triangular features are extracted from an ellipse and two points based on the polarity in 2-D projection space. A planar homography is first estimated by the triangular feature correspondences, then decomposed into 3-D pose parameters. The proposed method is evaluated through a series of experiments for analyzing the errors of 3-D pose estimation and the sensitivity with respect to point locations.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.2 no.6
• /
• pp.94-101
• /
• 1994

About vibration model of Six-degrees-of-freedom(DOF), in mass load, examined results for knowing dynamic interference and response variation is as follows; In case of putting mass load upon the object, experimented results on two-degrees-of-freedom of the translation-1 direction and the rotation-1 direction at open-loop-control system, about 0.19 arcsed in input of the translation-$0.1{\mu}m$ and $0.022{\mu}m$ on input of the rotation-0.5 arcsec, the justicse of motion equation is acknowledged as confirming the appearance of the interference-$0.022{\mu}m$. In establishing calculation of transformation matrix by using analogue circuit, as simulating results that used incomplete differentiation, interference is $1.7{\times}10^{-3}$ arcsec on input of the translation-$0.1{\mu}m$ and $1.4{\times}10^{4}{\mu}m$ on input of the rotation-0.5 arcsec in open-loop-control system. Also it is $4.2{\times}10^{-4}$ arcsec on input of the translation-$0.1{\mu}m$ and $5.6{\times}10^{-5}{\mu}m$ on input of the rotation-0.5 arcesc in closed-loop-control system. As closed-loop-control system is better than open-loop-control system, equivalent accordance is confirmed on original response. Finally, fundamental validity of this theory is acknowledged.