• Title/Summary/Keyword: IR communication

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Luminescent Lanthanide Complexes for Advanced Photonics Applications

  • Eom, Yu Kyung;Ryu, Jung Ho;Kim, Hwan Kyu
    • Rapid Communication in Photoscience
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    • v.1 no.1
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    • pp.1-9
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    • 2012
  • Luminescent lanthanide complexes have been overviewed for advanced photonics applications. Lanthanide(III) ions ($Ln^{3+}$) were encapsulated by the luminescent ligands such as metalloporphyrins, naphthalenes, anthracene, push-pull diketone derivatives and boron dipyrromethene(bodipy). The energy levels of the luminescent ligands were tailored to maintain the effective energy transfer process from luminescent ligands to $Ln^{3+}$ ions for getting a higher optical amplification gain. Also, key parameters for emission enhancement and efficient energy transfer pathways for the sensitization of $Ln^{3+}$ ions by luminescent ligands were investigated. Furthermore, to enhance the optophysical properties of novel luminescent $Ln^{3+}$ complexes, aryl ether-functionalized dendrons as photon antennas have been incorporated into luminescent $Ln^{3+}$ complexes, yielding novel $Ln^{3+}$-cored dendrimer complex such as metalloporphyrins, naphthalenes, and anthracenes bearing the Fr$\acute{e}$chet aryl-ether dendrons, namely, ($Er^{3+}-[Gn-Pt-Por]_3$ (terpy), $Er^{3+}-[Gn-Naph]_3$(terpy) and $Er^{3+}-[Gn-An]_3$(terpy)). These complexs showed much stronger near-IR emission bands at 1530 nm, originated from the 4f-4f electronic transition of the first excited state ($^4I_{13/2}$) to the ground state ($^4I_{15/2}$) of the partially filled 4f shell. A significant decrease in the fluorescence of metalloporphyrins, naphthalenes and anthracene ligand were accompanied by a strong increase in the near IR emission of the $Ln^{3+}$ ions. The near IR emission intensities of $Ln^{3+}$ ions in the lanthanide(III)-encapsulated dendrimer complexes were dramatically enhanced with increasing the generation number (n) of dendrons, due to the site-isolation and the light-harvesting(LH) effects. Furthermore, it was first attempted to distinguish between the site-isolation and the light-harvesting effects in the present complexes. In this review, synthesis and photophysical studies of inert and stable luminescent $Ln^{3+}$ complexes will be dealt for the advanced photonics applications. Also, the review will include the exploratory investigation of the key parameters for emission enhancement and the effective energy transfer pathways from luminescent ligands to $Ln^{3+}$ ions with $Ln^{3+}$-chelated prototype complexes.

Improvement of Hysteresis Characteristics of Low Temperature Poly-Si TFTs (저온 Poly-Si TFT 소자의 Hysteresis 특성 개선)

  • Chung, Hoon-Ju;Cho, Bong-Rae;Kim, Byeong-Koo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.2 no.1
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    • pp.3-9
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    • 2009
  • Although Active matrix organic light emitting diode (AMOLED) display has a better image quality in terms of viewing angle, contrast ratio, and response time than liquid crystal displays (LCDs), it still has some critical issues such as lifetime, residual images, and brightness non-uniformity due to non-uniformity in electrical characteristics of driving TFTs and IR drops on supplied power line. Among them, we improved irrecoverable residual images of AMOLED displays which is mainly related to the hysteresis characteristics of driving TFTs. We consider four kinds of surface treatment conditions before gate oxide deposition for improving hysteresis characteristics. We can reduce the hysteresis level of p-channel TFT to 0.23 V, interface trap states between the poly-Si layer and gate insulator to $3.11{\times}10^{11}cm^{-2}$, and output current variation of p-channel TFT to 3.65 % through the surface treatment using ultraviolet light and H2 plasma. Therefore, the recoverable residual image problem of AMOLED displays can be improved by surface treatment using ultraviolet light and $H_2$ plasma.

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Real Time Gaze Discrimination for Computer Interface (컴퓨터 인터페이스를 위한 실시간 시선 식별)

  • Hwang, Suen-Ki;Kim, Moon-Hwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.1
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    • pp.38-46
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    • 2010
  • This paper describes a computer vision system based on active IR illumination for real-time gaze discrimination system. Unlike most of the existing gaze discrimination techniques, which often require assuming a static head to work well and require a cumbersome calibration process for each person, our gaze discrimination system can perform robust and accurate gaze estimation without calibration and under rather significant head movement. This is made possible by a new gaze calibration procedure that identifies the mapping from pupil parameters to screen coordinates using generalized regression neural networks (GRNNs). With GRNNs, the mapping does not have to be an analytical function and head movement is explicitly accounted for by the gaze mapping function. Furthermore, the mapping function can generalize to other individuals not used in the training. To further improve the gaze estimation accuracy, we employ a reclassification scheme that deals with the classes that tend to be misclassified. This leads to a 10% improvement in classification error. The angular gaze accuracy is about $5^{\circ}$horizontally and $8^{\circ}$vertically. The effectiveness of our gaze tracker is demonstrated by experiments that involve gaze-contingent interactive graphic display.

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A Trend Analysis of the Metro Sections of News Media in Korea during 1998 and 2009 (사회면 기사 분석(1998년~2009년)을 통해 본 뉴스 미디어의 현실구성)

  • Jeong, Ir-Kwon
    • Korean journal of communication and information
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    • v.50
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    • pp.143-163
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    • 2010
  • This study explores the headlines of the metro sections posted in the major domestic news media during 1998 and 2009 and examines if the media contribute to construction of the reality. The data were systematical sampled from three main evening news programs representing each broadcasting company and the seven major nationwide newspapers (n=53,765). Results suggest the selection of news items should be influenced by the property of the regime and the trend for the time. This influence led to similarity among the news media to some extent, which are partially explained by the objectivity principle guiding the whole process of news making. Meanwhile, there was clear difference among the news media in general, and between the medium (broadcasting vs. newspaper) and within a medium, more specifically. The difference can be explained by the interaction of the property of the regime and the trend for the time and other factors including journalistic paradigm and ownership of each company.

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A Development of the High-Performance Signal Processor for the Compact Millimeter Wave Radar (소형 밀리미터파 레이더를 위한 고성능 신호처리기 개발)

  • Choi, Jin-Kyu;Ryu, Han-Chun;Park, Seung-Wook;Kim, Ji-Hyun;Kwon, Jun-Beom
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.6
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    • pp.161-167
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    • 2017
  • Recently, small radar has been reduced in size and power consumption to cope with various operating environments. It also requires the development of a small millimeter wave radar with high range resolution to disable the system of target with a single strike. In this paper, we design and implement a signal processor that can be used in small millimeter wave radar. The signal processor for the small millmeter wave radar is designed with a digital IF(Intermediate Frequency) receiver and DFT(Discrete Fourier Transform) module capable of real time FFT operation for miniaturization and low power consumption. Also it was to leverage the FPGA(Field Programmable Gate Array) and DAC(Digital Analog Converter) as a means for correcting the distortion of signals that can occur in the receive path of the small millimeter wave radar to create a RF signal that is used by the system. Finally, we verified the signal processor presented through performance test

Autonomous Mobile Robot Control using the Wearable Devices Based on EMG Signal for detecting fire (EMG 신호 기반의 웨어러블 기기를 통한 화재감지 자율 주행 로봇 제어)

  • Kim, Jin-Woo;Lee, Woo-Young;Yu, Je-Hun;Sim, Kwee-Bo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.3
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    • pp.176-181
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    • 2016
  • In this paper, the autonomous mobile robot control system for detecting fire was proposed using the wearable device based on EMG(Electromyogram) signal. Myo armband is used for detecting the user's EMG signal. The gesture was classified after sending the data of EMG signal to a computer using Bluetooth communication. Then the robot named 'uBrain' was implemented to move by received data from Bluetooth communication in our experiment. 'Move front', 'Turn right', 'Turn left', and 'Stop' are controllable commands for the robot. And if the robot cannot receive the Bluetooth signal from a user or if a user wants to change manual mode to autonomous mode, the robot was implemented to be in the autonomous mode. The robot flashes the LED when IR sensor detects the fire during moving.

A Study on Real-time Data Preprocessing Technique for Small Millimeter Wave Radar (소형 밀리미터파 레이더를 위한 실시간 데이터 전처리 방법 연구)

  • Choi, Jinkyu;Shin, Youngcheol;Hong, Soonil;Park, Changhyun;Kim, Younjin;Kim, Hongrak;Kwon, Junbeom
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.6
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    • pp.79-85
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    • 2019
  • Recently, small radar require the development of small millimeter wave radar with high distance resolution to disable the target's system with a single strike. Small millimeter wave radar with high distance resolution need to process large amounts of data in real time to acquire and track target. In this paper, we summarized the real-time data preprocessing method to process the large amount of data required for small millimeter wave radar. In addition, the digital IF(Intermediate Frequency) receiver, Window processing, and, DFT(Discrete Fourier Transform) functions presented by real-time data preprocessing are implemented using FPGA(Field Programmable Gate Array). Finally the implemented real-time data preprocessing module was applied to the signal processor for small millimeter wave radar and verified by performance test related to the real-time preprocessing function.

Detection of Moving Objects using Depth Frame Data of 3D Sensor (3D센서의 Depth frame 데이터를 이용한 이동물체 감지)

  • Lee, Seong-Ho;Han, Kyong-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.5
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    • pp.243-248
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    • 2014
  • This study presents an investigation into the ways to detect the areas of object movement with Kinect's Depth Frame, which is capable of receiving 3D information regardless of external light sources. Applied to remove noises along the boundaries of objects among the depth information received from sensors were the blurring technique for the x and y coordinates of pixels and the frequency filter for the z coordinate. In addition, a clustering filter was applied according to the changing amounts of adjacent pixels to extract the areas of moving objects. It was also designed to detect fast movements above the standard according to filter settings, being applicable to mobile robots. Detected movements can be applied to security systems when being delivered to distant places via a network and can also be expanded to large-scale data through concerned information.

Active Facial Tracking for Fatigue Detection (피로 검출을 위한 능동적 얼굴 추적)

  • Kim, Tae-Woo;Kang, Yong-Seok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.2 no.3
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    • pp.53-60
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    • 2009
  • The vision-based driver fatigue detection is one of the most prospective commercial applications of facial expression recognition technology. The facial feature tracking is the primary technique issue in it. Current facial tracking technology faces three challenges: (1) detection failure of some or all of features due to a variety of lighting conditions and head motions; (2) multiple and non-rigid object tracking; and (3) features occlusion when the head is in oblique angles. In this paper, we propose a new active approach. First, the active IR sensor is used to robustly detect pupils under variable lighting conditions. The detected pupils are then used to predict the head motion. Furthermore, face movement is assumed to be locally smooth so that a facial feature can be tracked with a Kalman filter. The simultaneous use of the pupil constraint and the Kalman filtering greatly increases the prediction accuracy for each feature position. Feature detection is accomplished in the Gabor space with respect to the vicinity of predicted location. Local graphs consisting of identified features are extracted and used to capture the spatial relationship among detected features. Finally, a graph-based reliability propagation is proposed to tackle the occlusion problem and verify the tracking results. The experimental results show validity of our active approach to real-life facial tracking under variable lighting conditions, head orientations, and facial expressions.

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Unplugged Robot Coding System Based on Remote Interface (리모컨 인터페이스 기반의 언플러그드 로봇 코딩 시스템)

  • Lee, Jun;Seo, Yong-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.5
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    • pp.157-162
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    • 2019
  • Recently, the awareness of S/W education, which was confined to the profession, is changing due to the changing industrial environment based on ICT technology World main countries invest competitively in S/W education and the target age group is getting lower Among them, the unplugged coding method using the robot platform is known as one of the most effective S/W training methods targeting the elementary age by the intuitive coding method and the robot platform feedback. However, the unplugged coding method using the robot platform has a disadvantage that it can not configure various interfaces for complicated coding due to limitations of H/W. In this paper, we have proposed an unplugged coding system which can input various commands for robot control by IR remote control as an interface and minute signals using robot sensor.