• Title/Summary/Keyword: Edge detection

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A study on Simple and Complex Algorithm of Self Controlled Mobile Robot for the Obstacle Avoidance and Path Plan (자율 이동로봇의 장애물 회피 및 경로계획에 대한 간략화 알고리즘과 복합 알고리즘에 관한 연구)

  • 류한성;최중경;구본민;박무열;권정혁
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.1
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    • pp.115-123
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    • 2002
  • In this paper, we present two types of vision algorithm that mobile robot has CCD camera. for obstacle avoidance and path plan. One is simple algorithm that compare with grey level from input images. Also, The mobile robot depend on image processing and move command from PC host. we has been studied self controlled mobile robot system with CCD camera. This system consists of TMS320F240 digital signal processor, step motor, RF module and CCD camera. we used wireless RF module for movable command transmitting between robot and host PC. This robot go straight until 95 percent filled screen from input image. And the robot recognizes obstacle about 95 percent filled something, so it could avoid the obstacle and conclude new path plan. Another is complex algorithm that image preprocessing by edge detection, converting, thresholding and image processing by labeling, segmentation, pixel density calculation.

The development of product inspection X-ray DR image processing system using intensifying screen (형광지를 이용한 물품검사 X-선 DR 영상처리 시스템 개발)

  • Park, Mun-kyu;Moon, Ha-jung;Lee, Dong-hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.7
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    • pp.1737-1742
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    • 2015
  • In the industrial field for product inspection needs not only on the surface of the product but also the internal components defect inspection. Generally, optical inspection is mainly used for item inspection from production process. However, this is only to check defect of surface it is difficult to perform inspection of goods internal. To overcome these limitations, Instead of optical device by using the portable X- ray DR image acquisition device system developed to obtain an image in real time at the same time and determine product defects. After obtaining the X- ray image, the inspection product within error range is passed after machine image processing. Also, the results and numbers are stored by users.

New Tie-over Dressing Method Using Hooks and Rubber Bands (갈고리와 고무밴드를 이용한 새로운 봉합고정드레싱법)

  • Kim, Gook-Jin;Lee, Youn-Jung;Kim, Nam-Gyun;Kim, Jun-Sik;Lee, Kyung-Suk
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.552-554
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    • 2011
  • Purpose: Though its general usage, traditional tie-over dressing using suture has a few drawbacks such as difficulty in re-fixation after its opening especially when hematoma or seroma has occurred. It is rather difficult to maintain a stable dressing on curvy parts of body like flank, buttocks and that leads to unsatisfactory results of the surgery. Authors recommend a quick and repeatedly doable method, tie-over dressing that incorporates the usage of hooks and rubber bands. Methods: Debridement was done at a recipient site to be able to do skin graft. A right size of skin graft was prepared and placed upon the defect site with suture. Enough number of hooks were attached using Blue nylon at the normal skin of the edge of grafted area. We Applied dressing with ointment and fluffy gauze then fixed the dressing by attaching a rubber band at the hook to give a certain amount of tension. One or two days after the surgery, we opened the tie-over dressing and repeated the tie-over dressing by reusing the hooks and rubber band. Results: The skin grafts were all successfully taken and by repeating tie-over dressing using hooks and rubber, we could take the advantage of shortened the dressing time and eliminate the inconvenience of the patient and the surgeon by using bandages and fixing tapes. Conclusion: The advantage of tie over dressing using hooks and rubber bsnds are its easy re-doability early detection of probable complications, preventability of reoccurence of hematoma and seroma. Therefore, authors report this as considering the tie-over dressing using hooks and rubber bands is recommendable.

Use of $^{99m}TcO_4^-$ Salivary-Thyroid Ratio As a Test of Thyroid Function (갑상선스캔상에서 갑상선섭취율의 추정방법 : 타액선-갑상선계수율)

  • Yang, Woo-Jin;Chung, Soo-Kyo;Chun, Ki-Sung;Kim, Jong-Woo;Bahk, Yong-Whee
    • The Korean Journal of Nuclear Medicine
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    • v.21 no.2
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    • pp.151-154
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    • 1987
  • Total 114 patients were studied prospectively with radioiodine uptake (RAIU) and $^{99m}TcO_4^-$ thyroid scan to design a very simple, rapid and inexpensive method measuring the thyroid uptake on thyroid scan. After the RAIU was obtained at 24 hours after P.O. of $^{131}I$, Thyroid scan was performed at 20 minutes after LV. of $^{99m}TcO_4^-$ and the bilateral salivary glands were included in the scan field. Pinhole collimated and computer assisted gamma camera was used. Three regions of interest were set on each salivary gland and on the thyroid by automatic edge detection method. Mean counts per pixel were calculated for each ROI and the salivary-thyroid ratio (STR) was defined as; $$STR(%)=\frac{Mean\;counts\;per\;pixel\;of\;salivary\;glands\;(KC)}{Mean\;counts\;per\;pixel\;of\;thyroid\;gland\;(KC)}\times100$$ 114 cases consisted of 41 normal, 55 hyperthyroid and 18 hypothyroid patients and correlation between the STR and the RAID were evaluated in total and each group. The STR and the RAID showed reverse linear regression in 114 cases (r= -0.8, P=0) and closer correlation was shown in hyperthyroid group (r= -0_9, p=0). Mean STR in normal group was 47.6%. In predicting the RAID by STR, sensitivity and specificity were 88.3% and 64.9% in 114 cases and 95.3% and 83.3% in hyperthyroid group. It is recommended that the STR be used in place of the RAID giving same information at saving time, money and radiation exposure.

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An Image Watermarking Scheme by Image Fusion in the Wavelet Domain (웨이블릿영역에서 영상융합에 의한 영상 워터마킹 기법)

  • Kim, Dong-Hyun;Choi, In-Ha
    • Journal of Korea Multimedia Society
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    • v.11 no.4
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    • pp.443-453
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    • 2008
  • In this paper, the 1-level DWT(Discrete Wavelet Transform) coefficients of a binary logo image are used as the watermark. The watermark should be inserted in the same band which is equivalent to the host image when the watermark is inserted in the wavelet domain. This is the image fusion of the proposed watermarking method. The watermark is inserted in relatively significant coefficients after the insertion area is defined. The more significant coefficients have the important information because they are identified as the edge and major surface in images. The significant coefficients are defined when their absolute value exceeds the threshold. The standard deviation is used as the weight value of watermark insertion in order to strengthen the weight of the watermark insertion according to the value of the coefficients. The proposed watermarking method is an adaptive scheme, and the proposed two detection algorithms can be adaptively used when the watermarked image is distorted by cropping, filtering, or compression.

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Region-of-Interest Detection using the Energy from Vocal Fold Image (성대 영상에서 에너지를 이용한 관심 영역 추출)

  • Kim, Eom-Jun;Sung, Mee-Young
    • Journal of KIISE:Software and Applications
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    • v.27 no.8
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    • pp.804-814
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    • 2000
  • In this paper, we propose an effective method to detect the regions of interests in the Videostrobokymography System. Videostrobokymography system is a medical image processing system for extracting automatically the diagnosis parameters from the irregular vibratory movements of the vocal fold. We detect the regions of interests through three steps. In the first step, we remove the noise in the input image and we find the minimum energy value in each frame. In the second step, we computed the edge by everage value for the one line. In the third step, the regions of interests can be extracted by using the Merge Algorithm which uses the variance of luminance as the feature points. We experimented this method for the vocal fold images of nineteen patients. In consequence, the regions of interests are detected in most vocal fold images. The method proposed in this study is efficient enough to extract the region of interests in the vocal fold images with the frame rate of 40 frames/second and the resolution of 200${\times}$280 pixels.

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Regulation of Contraction and $Ca^{2+}$ Transient by Histidine-rich $Ca^{2+}$-binding Protein in Ventricular Myocytes (히스티딘-리치 $Ca^{2+}$ 결합 단백질에 의한 심실근세포 수축 및 $Ca^{2+}$ Transient의 조절)

  • Son, Min-Jeong;Kim, Joon-Chul;Kim, Seong-Woo;Ahn, Jong-Real;Woo, Sun-Hee
    • YAKHAK HOEJI
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    • v.56 no.6
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    • pp.377-381
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    • 2012
  • The histidine-rich $Ca^{2+}$ binding protein (HRC) is a $Ca^{2+}$ binding protein in the sarcoplasmic reticulum (SR). In this study, we examined whether the HRC is involved in the regulation of cardiac contraction and $Ca^{2+}$ signaling using HRC knock-out (KO) mouse ventricular myocytes. In field-stimulated single mouse ventricular myocytes, cell shortenings and $Ca^{2+}$ transients were measured using a video edge detection and a confocal $Ca^{2+}$ imaging, respectively. Compared with the wide-type (WT) myocytes, the magnitudes of cell shortenings were significantly larger in HRC KO cells (P<0.01, WT vs. KO). The rate of contraction and relaxation was significantly accelerated in HRC KO myocytes (P<0.05 and P<0.01, respectively, WT vs. KO). The magnitudes of $Ca^{2+}$ transients were increased by HRC KO (P<0.01, WT vs. KO). In addition, the decay of the $Ca^{2+}$ transient was faster in HRC KO cells than in wild-type cells P<0.01, WT vs. KO). These results suggest that HRC may suppress SR $Ca^{2+}$ releases and decay of $Ca^{2+}$ transients during action potentials, thereby attenuating ventricular contraction and relaxation.

Efficient Flash Memory Access Power Reduction Techniques for IoT-Driven Rare-Event Logging Application (IoT 기반 간헐적 이벤트 로깅 응용에 최적화된 효율적 플래시 메모리 전력 소모 감소기법)

  • Kwon, Jisu;Cho, Jeonghun;Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.14 no.2
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    • pp.87-96
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    • 2019
  • Low power issue is one of the most critical problems in the Internet of Things (IoT), which are powered by battery. To solve this problem, various approaches have been presented so far. In this paper, we propose a method to reduce the power consumption by reducing the numbers of accesses into the flash memory consuming a large amount of power for on-chip software execution. Our approach is based on using cooperative logging structure to distribute the sampling overhead in single sensor node to adjacent nodes in case of rare-event applications. The proposed algorithm to identify event occurrence is newly introduced with negative feedback method by observing difference between past data and recent data coming from the sensor. When an event with need of flash access is determined, the proposed approach only allows access to write the sampled data in flash memory. The proposed event detection algorithm (EDA) result in 30% reduction of power consumption compared to the conventional flash write scheme for all cases of event. The sampled data from the sensor is first traced into the random access memory (RAM), and write access to the flash memory is delayed until the page buffer of the on-chip flash memory controller in the micro controller unit (MCU) is full of the numbers of the traced data, thereby reducing the frequency of accessing flash memory. This technique additionally reduces power consumption by 40% compared to flash-write all data. By sharing the sampling information via LoRa channel, the overhead in sampling data is distributed, to reduce the sampling load on each node, so that the 66% reduction of total power consumption is achieved in several IoT edge nodes by removing the sampling operation of duplicated data.

Method for Road Vanishing Point Detection Using DNN and Hog Feature (DNN과 HoG Feature를 이용한 도로 소실점 검출 방법)

  • Yoon, Dae-Eun;Choi, Hyung-Il
    • The Journal of the Korea Contents Association
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    • v.19 no.1
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    • pp.125-131
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    • 2019
  • A vanishing point is a point on an image to which parallel lines projected from a real space gather. A vanishing point in a road space provides important spatial information. It is possible to improve the position of an extracted lane or generate a depth map image using a vanishing point in the road space. In this paper, we propose a method of detecting vanishing points on images taken from a vehicle's point of view using Deep Neural Network (DNN) and Histogram of Oriented Gradient (HoG). The proposed algorithm is divided into a HoG feature extraction step, in which the edge direction is extracted by dividing an image into blocks, a DNN learning step, and a test step. In the learning stage, learning is performed using 2,300 road images taken from a vehicle's point of views. In the test phase, the efficiency of the proposed algorithm using the Normalized Euclidean Distance (NormDist) method is measured.

Automatic Target Recognition for Camera Calibration (카메라 캘리브레이션을 위한 자동 타겟 인식)

  • Kim, Eui Myoung;Kwon, Sang Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.6
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    • pp.525-534
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    • 2018
  • Camera calibration is the process of determining the parameters such as the focal length of a camera, the position of a principal point, and lens distortions. For this purpose, images of checkerboard have been mainly used. When targets were automatically recognized in checkerboard image, the existing studies had limitations in that the user should have a good understanding of the input parameters for recognizing the target or that all checkerboard should appear in the image. In this study, a methodology for automatic target recognition was proposed. In this method, even if only a part of the checkerboard image was captured using rectangles including eight blobs, four each at the central portion and the outer portion of the checkerboard, the index of the target can be automatically assigned. In addition, there is no need for input parameters. In this study, three conditions were used to automatically extract the center point of the checkerboard target: the distortion of black and white pattern, the frequency of edge change, and the ratio of black and white pixels. Also, the direction and numbering of the checkerboard targets were made with blobs. Through experiments on two types of checkerboards, it was possible to automatically recognize checkerboard targets within a minute for 36 images.