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Development of 360° Omnidirectional IP Camera with High Resolution of 12Million Pixels (1200만 화소의 고해상도 360° 전방위 IP 카메라 개발)

  • Lee, Hee-Yeol;Lee, Sun-Gu;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.21 no.3
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    • pp.268-271
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    • 2017
  • In this paper, we propose the development of high resolution $360^{\circ}$ omnidirectional IP camera with 12 million pixels. The proposed 12-megapixel high-resolution $360^{\circ}$ omnidirectional IP camera consists of a lens unit with $360^{\circ}$ omnidirectional viewing angle and a 12-megapixel high-resolution IP camera unit. The lens section of $360^{\circ}$ omnidirectional viewing angle adopts the isochronous lens design method and the catadioptric facet production method to obtain the image without peripheral distortion which is inevitably generated in the fisheye lens. The 12 megapixel high-resolution IP camera unit consists of a CMOS sensor & ISP unit, a DSP unit, and an I / O unit, and converts the image input to the camera into a digital image to perform image distortion correction, image correction and image compression And then transmits it to the NVR (Network Video Recorder). In order to evaluate the performance of the proposed 12-megapixel high-resolution $360^{\circ}$ omnidirectional IP camera, 12.3 million pixel image efficiency, $360^{\circ}$ omnidirectional lens angle of view, and electromagnetic certification standard were measured.

Improvement of PWM Driving Control Characteristics for Low Power LED Security Light (저전력형 LED 보안등의 PWM형 구동제어 특성 개선)

  • Park, Hyung-Jun;Kim, Nag-Cheol;Kim, In-Su
    • Journal of IKEEE
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    • v.21 no.4
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    • pp.368-374
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    • 2017
  • In this Paper, we developed a low power type LED security light using LED lighting that substitutes a 220[V] commercial power source for a solar cell module instead of a halogen or a sodium lamp. in addition, a PWM type drive control circuit is designed to minimize the heat generation problem and the drive current of the LED drive controller. in developed system, The light efficiency measurement value is 93.6[lm/W], and a high precision temperature sensor is used inside the controller to control the heat generation of the LED lamp. In order to eliminate the high heat generated from the LED lamp, it is designed to disperse quickly into the atmosphere through the metal insertion type heat sink. The heat control range of LED lighting was $50-55[^{\circ}C]$. The luminous flux and the lighting speed of the LED security lamp were 0.5[s], and the beam diffusion angle of the LED lamp was about $110[^{\circ}C]$ by the light distribution curve based on the height of 6[m].

A study on traffic signal control at signalized intersections in VANETs (VANETs 환경에서 단일 교차로의 교통신호 제어방법에 관한 연구)

  • Chang, Hyeong-Jun;Park, Gwi-Tae
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.6
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    • pp.108-117
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    • 2011
  • Seoul metropolitan government has been operating traffic signal control system with the name of COSMOS since 2001. COSMOS uses the degrees of saturation and congestion which are calculated by installing loop detectors. At present, inductive loop detector is generally used for detecting vehicles but it is inconvenient and costly for maintenance since it is buried on the road. In addition, the estimated queue length might be influenced in case of error occurred in measuring speed, because it only uses the speed of vehicles passing by the detector. A traffic signal control algorithm which enables smooth traffic flow at intersection is proposed. The proposed algorithm assigns vehicles to the group of each lane and calculates traffic volume and congestion degree using traffic information of each group using VANETs(Vehicular Ad-hoc Networks) inter-vehicle communication. It does not demand additional devices installation such as cameras, sensors or image processing units. In this paper, the algorithm we suggest is verified for AJWT(Average Junction Waiting Time) and TQL(Total Queue Length) under single intersection model based on GLD(Green Light District) Simulator. And the result is better than Random control method and Best first control method. In case real-time control method with VANETs is generalized, this research that suggests the technology of traffic control in signalized intersections using wireless communication will be highly useful.

The study on scheme for train position detection based on GPS/DR (GPS/DR기반의 차상열차위치검지방안 연구)

  • Shin, Kyung-Ho;Joung, Eui-Jin;Lee, Jun-Ho
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.802-810
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    • 2006
  • For a thorough train control, the precise train position detection is necessarily required. The widely used current way for train position detection is the one of using track circuits. The track circuit has a simple structure, and has a high level of reliability. However trains can be detected only on track circuits, which have to be installed on all ground sections, and much amount of cost for its installation and maintenance is needed. In addition, for the track circuit, only discontinuous position detection is possible because of the features of the closed circuit loop configuration. As the recent advances in telecommunication technologies and high-tech vehicle-based control equipments, for the train position detection, the method to detect positions directly from on trains is being studied. Vehicle-based position detection method is to estimate train positions, speed, timing data continuously, and to use them as the control information. In this paper, the features of GPS navigation and DR navigation are analyzed, and the navigation filters are designed by constructing vehicle-based train position detection method by combining GPS navigation and DR navigation for their complementary cooperation, and by using kalman filter. The position estimation performance of the proposed method is also confirmed by simulations.

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Human-Computer Interface using sEMG according to the Number of Electrodes (전극 개수에 따른 근전도 기반 휴먼-컴퓨터 인터페이스의 정확도에 대한 연구)

  • Lee, Seulbi;Chee, Youngjoon
    • Journal of the HCI Society of Korea
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    • v.10 no.2
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    • pp.21-26
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    • 2015
  • NUI (Natural User Interface) system interprets the user's natural movement or the signals from human body to the machine. sEMG (surface electromyogram) can be observed when there is any effort in muscle even without actual movement, which is impossible with camera and accelerometer based NUI system. In sEMG based movement recognition system, the minimal number of electrodes is preferred to minimize the inconvenience. We analyzed the decrease in recognition accuracy as decreasing the number of electrodes. For the four kinds of movement intention without movement, extension (up), flexion (down), abduction (right), and adduction (left), the multilayer perceptron classifier was used with the features of RMS (Root Mean Square) from sEMG. The classification accuracy was 91.9% in four channels, 87.0% in three channels, and 78.9% in two channels. To increase the accuracy in two channels of sEMG, RMSs from previous time epoch (50-200 ms) were used in addition. With the RMSs from 150 ms, the accuracy was increased from 78.9% to 83.6%. The decrease in accuracy with minimal number of electrodes could be compensated partly by utilizing more features in previous RMSs.

Development of Sludge Concentration Estimation Method using Neuro-Fuzzy Algorithm (뉴로-퍼지 알고리즘을 이용한 슬러지 농도 추정 기법 개발)

  • Jang, Sang-Bok;Lee, Ho-Hyun;Lee, Dae-Jong;Kweon, Jin-Hee;Chun, Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.2
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    • pp.119-125
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    • 2015
  • A concentration meter is widely used at purification plants, sewage treatment plants and waste water treatment plants to sort and transfer high concentration sludge and to control the amount of chemical dosage. When the strange substance is contained in the sludge, however, the attenuation of ultrasonic wave could be increased or not be transmitted to the receiver. At that case, the value of concentration meter is higher than the actual density value or vibrated up and down. It has also been difficult to automate the residuals treatment process according to the problems as sludge attachment or damage of a sensor. Multi-beam ultrasonic concentration meter has been developed to solve these problems, but the failure of the ultrasonic beam of a specific concentration measurement value degrade the performance of the entire system. This paper proposes the method to improve the accuracy of sludge concentration rate by choosing reliable sensor values and learning them by proposed algorithm. The prediction algorithm is chosen as neuro-fuzzy model, which is tested by the various experiments.

Development of a New Training System for the Improvement of Equibrilium Sense (평형 감각 증진을 위한 새로운 훈련 장치의 개발)

  • Lee Jung Ok;Park Young Gun;No Pang Hwang;Hong Chul Un;Kim Nam Gyun
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.465-469
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    • 2004
  • We propose a new training system for the improvement of equilibrium sense using unstable platform. This system consists of unstable platform, computer interface and various softwares. The unstable platform was a simple structure of elliptical-type which included tilt sensor and wireless RF module. To evaluate the effort of balance training, we measured the parameters such as the moving time to the target and duration to maintain cursor in the target of screen. Balance training was carried out for two weeks and we classified the subjects into two groups by the training program. As a result, the moving time was reduced and duration time was lengthened through the repeating training of equilibrium sense using training program of sine curve trace(SCT) and Block game. Especially, there was remarkable improvement at direction which was too difficult for the subjects to balance their body. It was showed that this system had an effort on improving equilibrium sense and might be applied to clinical use as an effective balance training system.

A Study on the Energy and Time Characteristics of $BaF_2$ Scintillation Detector ($BaF_2$ 검출기의 시간과 에너지 특성연구)

  • Ju, Gwan-Sik;Park, Il-Jin;Kim, Jong-Ho;Nam, Gi-Yong;Baek, Seung-Hwa
    • Journal of Biomedical Engineering Research
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    • v.18 no.3
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    • pp.267-272
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    • 1997
  • he scintillation detector having $BaF^2$ crystal with 3.6cm dia${\times}$2.0 cm thick was provided. The energy and timing characteristics were measured and compared with NaI(Tl) scintillation detectors, which widely used in unclear medicine. In order to measure the energy spectrum, the radioactive sources used were $^{22}Na,\;^{54}Mn,\;^{57}Co,\;^{137}Cs$ and the source to detector distance was 7cm. For the timing characteristic, NaI(Tl)(1" ${\times}$ 1")-$BaF^2$ and NaI(Tl)(3" ${\times}$ 3")-$BaF^2$ timing coincidence systems were prepared and the used source was $^{22}Na$ emitting 511keV annihilation photons. For the 511keV gamma-ray emitted from $^{22}Na$, It was revealed that the timing response of the $BaF^2$ detector was faster than NaI(Tl)(1" ${\times}$ 1") and NaI(Tl)(3" ${\times}$ 3") detector used in this experimental investigation. The energy characteristics of the $BaF^2$ detector had a good values for about 500keV energy range.

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A Design and Implementation of Busbar Joint and Temperature Measurement System (부스바 접촉 상태 및 온도 감지 시스템 설계 및 구현)

  • Lee, Young-dong;Jeong, Sung-Hak
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.2
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    • pp.379-385
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    • 2017
  • In general, distribution board, panel board and motor control center can be installed over a wide area such as residence of group, building, schools, factories, ports, airports, water service and sewerage, substation and heavy industries that are used to supply converts the voltages extra high voltage into optimal voltage. There are electrical accidents due to rise of contact temperature, loose contact between busbar, deterioration of the contact resistance, over temperature of the busbars. In this paper, we designed and implemented the busbar joint and temperature measurement system, which can measure the joint resistance of busbar and loose connection between busbar using potentiometer and non-contact infrared sensor. The experimental results show that tightening the bolt and nut is fully engaged, resistance was decreased and maximum error range was 0.1mm. Also, the experimental result showed that the temperature at the contact area is increased from $27.3^{\circ}C$ to $69.3^{\circ}C$by the contact resistance.

A Study on Estimation of Gait Acceleration Signal Using Gait Video Signal in Wearable Device (걸음걸이 비디오를 활용한 웨어러블 기기 사용자 걸음걸이 가속도 신호 추정)

  • Lee, Duhyeong;Choi, Wonsuk;Lee, Dong Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.6
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    • pp.1405-1417
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    • 2017
  • Researches that apply the acceleration signal due to user's gait measured at the wearable device to the authentication technology are being introduced recently. The gait acceleration signal based authentication technologies introduced so far have assumed that an attacker can obtain a user's gait acceleration signal only by attaching accelerometer directly to user's body. And the practical attack method for gait acceleration signal based authentication technology is mimic attack and it uses a person whose physical condition is similar to the victim or identifies the gait characteristics through the video of the gait of the victim. However, mimic attack is not effective and attack success rate is also very low, so it is not considered a serious threat. In this paper, we propose Video Gait attack as a new attack method for gait acceleration signal based authentication technology. It is possible to know the position of the wearable device from the user's gait video signal and generate a signal that is very similar to the accelerometer's signal using dynamic equation. We compare the user's gait acceleration signal and the signal that is calculated from video of user's gait and dynamic equation with experiment data collected from eight subjects.