• Title/Summary/Keyword: 웨이브렛

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Feature Extraction of Molecular Images by DWT (DWT에 의한 분자영상의 특징 추출)

  • Choi, Guirack;Ahng, Byungju;Lee, Sangbock
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.12
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    • pp.21-26
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    • 2013
  • In this paper, We are suggested methods of feature extraction in molecular images. The result of image transform DWT examination by suggested method, we are obtained as follows. 1-level and 2-levels of decomposition results showed the composition of the low frequency region. But, 3-level decomposition results did not appear in the data component is almost. Observed not with the naked eye is not, but the 3-level output data values of the results were decomposed. We are printed the horizontal and vertical directions of low-frequency region of the data, the high frequency region of the horizontal and vertical data, and diagonal high frequency region of the horizontal and vertical directions data. If the output data using molecular imaging and CT, PET, MR imaging will be compared with the data.

A Study on the Bandwidth Efficiency of MC-CDMA System (MC-CDMA 시스템에서 주파수 대역 효율에 관한 연구)

  • Jee, Innho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.21 no.6
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    • pp.43-48
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    • 2021
  • We propose 2-channel filter bank method instead of FFT method to decrease sub-channel interference for using of efficient frequency resource in MC-CDMA method. Since a prototype filter of filter bank having wavelet characteristic is designed having more less side-lobe, the nearest co-channel interference and inter symbol interference are decreased efficiently. Since the spreading signal of suggesting MC-CDMA system is being demanded for less chip rate and is not being considering for autocorrelation characteristic, the Walsh code can be used as a optimal orthogonal signal set. We consider bit error rate and signal to noise ratio to estimate the performance of suggested system on condition that white noise channel and arbitrary sinusoidal jammer are existing. As a result of comparing to traditional FFT-based MC-CDMA simulation result, our suggested system has shown better performance than traditional MC-CDMA method on the side of minimizing interference effect.

Integrity evaluation of grouting in umbrella arch methods by using guided ultrasonic waves (유도초음파를 이용한 강관보강다단 그라우팅의 건전도 평가)

  • Hong, Young-Ho;Yu, Jung-Doung;Byun, Yong-Hoon;Jang, Hyun-Ick;You, Byung-Chul;Lee, Jong-Sub
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.3
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    • pp.187-199
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    • 2013
  • Umbrella arch method (UAM) used for improving the stability of the tunnel ground condition has been widely applied in the tunnel construction projects due to the advantage of obtaining both reinforcement and waterproof. The purpose of this study is to develop the evaluation technique of the integrity of bore-hole in UAM by using a non-destructive test and to evaluate the possibility of being applied to the field. In order to investigate the variations of frequency depending on grouted length, the specimens with different grouted ratios are made in the two constraint conditions (free boundary condition and embedded condition). The hammer impact reflection method in which excitation and reception occur simultaneously at the head of pipe was used. The guided waves generated by hitting a pipe with a hammer were reflected at the tip and returned to the head, and the signals were received by an acoustic emission (AE) sensor installed at the head. For the laboratory experiments, the specimens were prepared with different grouted ratios (25 %, 50 %, 75 %, 100 %). In addition, field tests were performed for the application of the evaluation technique. Fast Fourier transform and wavelet transform were applied to analyze the measured waves. The experimental studies show that grouted ratio has little effects on the velocities of guided waves. Main frequencies of reflected waves tend to decrease with an increase in the grouted length in the time-frequency domain. This study suggests that the non-destructive tests using guided ultrasonic waves be effective to evaluate the bore-hole integrity of the UAM in the field.

Implementation of Intelligent Image Surveillance System based Context (컨텍스트 기반의 지능형 영상 감시 시스템 구현에 관한 연구)

  • Moon, Sung-Ryong;Shin, Seong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.3
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    • pp.11-22
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    • 2010
  • This paper is a study on implementation of intelligent image surveillance system using context information and supplements temporal-spatial constraint, the weak point in which it is hard to process it in real time. In this paper, we propose scene analysis algorithm which can be processed in real time in various environments at low resolution video(320*240) comprised of 30 frames per second. The proposed algorithm gets rid of background and meaningless frame among continuous frames. And, this paper uses wavelet transform and edge histogram to detect shot boundary. Next, representative key-frame in shot boundary is selected by key-frame selection parameter and edge histogram, mathematical morphology are used to detect only motion region. We define each four basic contexts in accordance with angles of feature points by applying vertical and horizontal ratio for the motion region of detected object. These are standing, laying, seating and walking. Finally, we carry out scene analysis by defining simple context model composed with general context and emergency context through estimating each context's connection status and configure a system in order to check real time processing possibility. The proposed system shows the performance of 92.5% in terms of recognition rate for a video of low resolution and processing speed is 0.74 second in average per frame, so that we can check real time processing is possible.

Defect ratio evaluation of the rock bolt grouting using the reflection method of guided ultrasonic waves (유도초음파의 반사법을 이용한 록볼트 그라우팅의 결함비율 평가)

  • Yu, Jung-Doung;Bae, Myeong-Ho;Han, Shin-In;Lee, In-Mo;Lee, Jong-Sub
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.10 no.3
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    • pp.221-232
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    • 2008
  • Rock bolts have been installed into rockmass as a main support system. In order to evaluate the rock bolt integrity using non-destructive technique, the transmission method of the guided ultrasonic wave has been successfully performed. For the transmission method, however, the source for the generation o# guided ultrasonic waves should be installed at the end of the steel bar during construction of the rock bolt in the field. The purpose of this study is to suggest a reflection method that the source and the receiver are installed on the head of the steel bar. The reflection method is compared with the transmission method using non-embedded rock bolts and rock bolts embedded in concrete block. In this experiment, the piezo disc element is used as the source and the AE sensor is used as the receiver. The wavelet transform is applied to determine the energy velocity. The experimental studies show that the reflection method produces almost identical value of the transmission method, and the energy velocity increases with the defect ratio. This study suggests that the reflection method of the guided ultrasonic wave may be a suitable method fur the rock bolt integrity evaluation in the field.

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Low-Cost Remote Power-Quality-Failure Monitoring System using Android APP and MCU (안드로이드 앱과 MCU를 이용한 저가형 원격 전원품질이상 감시 시스템)

  • Lim, Ho-Kyoun;Kim, Seo-Hwi;Lee, Seung-Hyeon;Choe, Sangho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.9
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    • pp.144-155
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    • 2013
  • This paper presents a low-cost remote power-quality-failure monitoring system (RPMS) using Android App and TI MCU (micro-controller unit), which is appliable to a micro-grid. The designed RPMS testbed consists of smart nodes, a server, and Android APPs. Especially, the C2000-series MCU-based RPMS smart node that is low-cost compared to existing monitoring systems has both a signal processing function for power signal processing and a data transmission function for power-quality monitoring data transmission. The signal processing function implements both a wavelet-based power failure detection algorithm including sag, swell, and interruption, and a FFT-based power failure detection algorithm including harmonics such that reliable and real-time power quality monitoring is guaranteed. The data transmission function implements a low-complexity RPMS transmission protocol and defines a simple data format (msg_Diag) for power monitoring message transmission. We may watch the monitoring data in real time both at a server and Android phone Apps connected to the WiFi network (or WAN). We use RS-232 (or Bluetooth) as the wired (or wireless) communication media between a server and nodes. We program the RPMS power-quality-failure monitoring algorithm using C language in the CCS (Code Composer Studio) 3.3 environment.

Development of the Railway Abrasion Measurement System using Camera Model and Perspective Transformation (카메라 모델과 투시 변환에 의한 레일 마모도 측정 시스템 개발)

  • Ahn, Sung-Hyuk;Kang, Dong-Eun;Moon, Hyoung-Deuk;Park, So-Yeon;Kim, Man-Cheol
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.1069-1077
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    • 2008
  • The railway abrasion measurement system have to satisfy two conditions to increase the measurement accuracy as follows. The laser region which is projected on the rail have to be extracted without the geometrical distortion. The mapping of the acquired laser region data on the rail profile have to be processed exactly. But, the conventional railway abrasion measurement system is deeply effected by the foreign substance( dust, rainwater, and so on ) on the railway or the sensitive response characteristic of the laser to the external measurement circumstance, and then the measurement errors arise from above factors. When the laser region is projected on the rail extracts from the acquired image, the interference of the light with the same frequency as the laser system occurs the serious problems. In the process of the mapping between the railway profile and the extracted laser region, the measurement accuracy is very highly effected by the geometrical distortion and the abnormal variation. In this Paper, we propose the novel method to increase the accuracy of the railway abrasion measurement dramatically. we designed and manufactured the high precision and fast image processing board with DSP Core and FPGA to measure the railway abrasion. The image processing board has the capability that the image of 1024X1280 from camera can be processed with the speed of 480 frame/sec. And, we apply the image processing algorithm base on the wavelet to extract the laser region is projected on the rail exactly. Finally, we developed high precision railway abrasion measurement system with the error range less than +/-0.5mm by which 2D image data is covered 3D data and mapped on the rail profile using the camera model and the perspective transform.

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Implementation of a Self Controlled Mobile Robot with Intelligence to Recognize Obstacles (장애물 인식 지능을 갖춘 자율 이동로봇의 구현)

  • 류한성;최중경
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.5
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    • pp.312-321
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    • 2003
  • In this paper, we implement robot which are ability to recognize obstacles and moving automatically to destination. we present two results in this paper; hardware implementation of image processing board and software implementation of visual feedback algorithm for a self-controlled robot. In the first part, the mobile robot depends on commands from a control board which is doing image processing part. We have studied the self controlled mobile robot system equipped with a CCD camera for a long time. This robot system consists of a image processing board implemented with DSPs, a stepping motor, a CCD camera. We will propose an algorithm in which commands are delivered for the robot to move in the planned path. The distance that the robot is supposed to move is calculated on the basis of the absolute coordinate and the coordinate of the target spot. And the image signal acquired by the CCD camera mounted on the robot is captured at every sampling time in order for the robot to automatically avoid the obstacle and finally to reach the destination. The image processing board consists of DSP (TMS320VC33), ADV611, SAA7111, ADV7l76A, CPLD(EPM7256ATC144), and SRAM memories. In the second part, the visual feedback control has two types of vision algorithms: obstacle avoidance and path planning. The first algorithm is cell, part of the image divided by blob analysis. We will do image preprocessing to improve the input image. This image preprocessing consists of filtering, edge detection, NOR converting, and threshold-ing. This major image processing includes labeling, segmentation, and pixel density calculation. In the second algorithm, after an image frame went through preprocessing (edge detection, converting, thresholding), the histogram is measured vertically (the y-axis direction). Then, the binary histogram of the image shows waveforms with only black and white variations. Here we use the fact that since obstacles appear as sectional diagrams as if they were walls, there is no variation in the histogram. The intensities of the line histogram are measured as vertically at intervals of 20 pixels. So, we can find uniform and nonuniform regions of the waveforms and define the period of uniform waveforms as an obstacle region. We can see that the algorithm is very useful for the robot to move avoiding obstacles.

RGB Channel Selection Technique for Efficient Image Segmentation (효율적인 이미지 분할을 위한 RGB 채널 선택 기법)

  • 김현종;박영배
    • Journal of KIISE:Software and Applications
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    • v.31 no.10
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    • pp.1332-1344
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    • 2004
  • Upon development of information super-highway and multimedia-related technoiogies in recent years, more efficient technologies to transmit, store and retrieve the multimedia data are required. Among such technologies, firstly, it is common that the semantic-based image retrieval is annotated separately in order to give certain meanings to the image data and the low-level property information that include information about color, texture, and shape Despite the fact that the semantic-based information retrieval has been made by utilizing such vocabulary dictionary as the key words that given, however it brings about a problem that has not yet freed from the limit of the existing keyword-based text information retrieval. The second problem is that it reveals a decreased retrieval performance in the content-based image retrieval system, and is difficult to separate the object from the image that has complex background, and also is difficult to extract an area due to excessive division of those regions. Further, it is difficult to separate the objects from the image that possesses multiple objects in complex scene. To solve the problems, in this paper, I established a content-based retrieval system that can be processed in 5 different steps. The most critical process of those 5 steps is that among RGB images, the one that has the largest and the smallest background are to be extracted. Particularly. I propose the method that extracts the subject as well as the background by using an Image, which has the largest background. Also, to solve the second problem, I propose the method in which multiple objects are separated using RGB channel selection techniques having optimized the excessive division of area by utilizing Watermerge's threshold value with the object separation using the method of RGB channels separation. The tests proved that the methods proposed by me were superior to the existing methods in terms of retrieval performances insomuch as to replace those methods that developed for the purpose of retrieving those complex objects that used to be difficult to retrieve up until now.