• Title/Summary/Keyword: DoS detection

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3D Face Alignment and Normalization Based on Feature Detection Using Active Shape Models : Quantitative Analysis on Aligning Process (ASMs을 이용한 특징점 추출에 기반한 3D 얼굴데이터의 정렬 및 정규화 : 정렬 과정에 대한 정량적 분석)

  • Shin, Dong-Won;Park, Sang-Jun;Ko, Jae-Pil
    • Korean Journal of Computational Design and Engineering
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    • v.13 no.6
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    • pp.403-411
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    • 2008
  • The alignment of facial images is crucial for 2D face recognition. This is the same to facial meshes for 3D face recognition. Most of the 3D face recognition methods refer to 3D alignment but do not describe their approaches in details. In this paper, we focus on describing an automatic 3D alignment in viewpoint of quantitative analysis. This paper presents a framework of 3D face alignment and normalization based on feature points obtained by Active Shape Models (ASMs). The positions of eyes and mouth can give possibility of aligning the 3D face exactly in three-dimension space. The rotational transform on each axis is defined with respect to the reference position. In aligning process, the rotational transform converts an input 3D faces with large pose variations to the reference frontal view. The part of face is flopped from the aligned face using the sphere region centered at the nose tip of 3D face. The cropped face is shifted and brought into the frame with specified size for normalizing. Subsequently, the interpolation is carried to the face for sampling at equal interval and filling holes. The color interpolation is also carried at the same interval. The outputs are normalized 2D and 3D face which can be used for face recognition. Finally, we carry two sets of experiments to measure aligning errors and evaluate the performance of suggested process.

Development of an Performance Evaluation Method for Vehicle Detector Speed Measurement Applying Uncertainty in Measurement (측정불확도를 적용한 차량검지기 속도측정 성능평가방법 개발)

  • Lee, Hwan-Pil;Kim, Yong-Man;Kang, Dong-Yun
    • International Journal of Highway Engineering
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    • v.14 no.2
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    • pp.165-174
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    • 2012
  • In this study, a method for evaluating the performance of speed measurements was developed to assess the qualities of a vehicle detector. The evaluation method considers measurement errors that are reflected in a reference speed. For this, the concept of uncertainty in measurement was applied to the development method. Other factors such as precedent study, statistical processing techniques, and speed measurement performance method of traffic enforcement equipment and vehicle detection systems were also reviewed. Through this process, the problems of the existing evaluation methods were derived and developed for the new performance evaluation method. Vehicle detectors that are installed in the field were evaluated using the traditional assessment methods and the developed method. As a result, for traditional assessment methods, it was found that evaluation criteria are acceptable, while developed method's criteria are not acceptable. This means that traditional assessment methods do not sufficiently consider errors in measurement, so it has potential to over-estimate for performance of evaluation equipment. On the other hand, it was represented that the developed method should include variable factor such as errors in measurement and more precise compared to traditional assessment methods.

3D Building Reconstruction and Visualization by Clustering Airborne LiDAR Data and Roof Shape Analysis

  • Lee, Dong-Cheon;Jung, Hyung-Sup;Yom, Jae-Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.6_1
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    • pp.507-516
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    • 2007
  • Segmentation and organization of the LiDAR (Light Detection and Ranging) data of the Earth's surface are difficult tasks because the captured LiDAR data are composed of irregularly distributed point clouds with lack of semantic information. The reason for this difficulty in processing LiDAR data is that the data provide huge amount of the spatial coordinates without topological and/or relational information among the points. This study introduces LiDAR data segmentation technique by utilizing histograms of the LiDAR height image data and analyzing roof shape for 3D reconstruction and visualization of the buildings. One of the advantages in utilizing LiDAR height image data is no registration required because the LiDAR data are geo-referenced and ortho-projected data. In consequence, measurements on the image provide absolute reference coordinates. The LiDAR image allows measurement of the initial building boundaries to estimate locations of the side walls and to form the planar surfaces which represent approximate building footprints. LiDAR points close to each side wall were grouped together then the least-square planar surface fitting with the segmented point clouds was performed to determine precise location of each wall of an building. Finally, roof shape analysis was performed by accumulated slopes along the profiles of the roof top. However, simulated LiDAR data were used for analyzing roof shape because buildings with various shapes of the roof do not exist in the test area. The proposed approach has been tested on the heavily built-up urban residential area. 3D digital vector map produced by digitizing complied aerial photographs was used to evaluate accuracy of the results. Experimental results show efficiency of the proposed methodology for 3D building reconstruction and large scale digital mapping especially for the urban area.

The Development of Landslide Predictive System using Measurement Information based on u-IT (u-IT기반 계측정보를 이용한 급경사지붕괴 예측 시스템 개발)

  • Cheon, Dong-Jin;Park, Young-Jik;Lee, Seung-Ho;Kim, Jeong-Seop;Jung, Do-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.5115-5122
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    • 2013
  • This paper has studied about the development and application of landslide collapse prediction real-time monitoring system based on USN to detect and measure the collapse of landslide. The rainfall measuring sensor, gap water pressure sensor, indicator displacement measuring sensor, index inclination sensor, water content sensor and image analysis sensor are selected and these are applied on the test bed. Each sensor's operation and performance for reliability verification is tested by the instrument which is installed in the field. As the result, u-IT based real-time landslide monitoring system which is developed by this research for landslide collapse detection could minimize life and property damages because it makes advance evacuation with collapse risk pre-estimate through real-time monitoring on roadside cut and bedrock slopes. This system is based on the results of this study demonstrate the effect escarpment plan are spread throughout.

Arterial Embolization for the Ruptured Splenic Artery Pseudoaneurysm in a Child (소아 가성비장동맥 파열의 동맥색전술 치험 1예)

  • Han, Seok-Joo;Lee, Do-Yun;Han, Ai-Ri;Choi, Gi-Hong;Oh, Jung-Tak;Choi, Seung-Hoon;Hwang, Eui-Ho
    • Advances in pediatric surgery
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    • v.6 no.2
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    • pp.143-148
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    • 2000
  • Pseudoaneurysm of the splenic artery may arise from a vascular erosion by a surrounding inflammatory processes in acute and chronic pancreatitis. Rupture of the pseudoaneurysm may threaten the patient's life. Conservative management for massive hemorrhage may cause 100 percent mortality and even with prompt therapy there is a high mortality. Preoperative detection of bleeding source is desirable because of the difficult identification of the bleeding site at laparotomy. Angiographic identification and embolization of the hemorrhagic vessels in selected cases may obviate the risk of urgent surgery. The authors have recently managed a case of ruptured splenic artery pseudoaneurysm combined with a pancreatic pseudocyst in a 6 years old boy. A bolus enhanced CT scan and angiography confirmed the diagnosis. We managed this child successfully with the urgent transcatheter arterial embolization followed by elective surgery.

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A Study of the SPWM High-Frequency Harmonic Circulating Currents in Modular Inverters

  • Xu, Sheng;Ji, Zhendong
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2119-2128
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    • 2016
  • Due to detection and control errors, some high-frequency harmonics with voltage-source characteristics cause circulating currents in modular inverters. Moreover, the circulating currents are usually affected by the output filters (OF) of each module due to their filter and resonance properties. The interaction among the circulating currents in the modules increase the power loss and reduce system stability and control precision. Therefore, this paper reports the results of a study on the SPWM high-frequency harmonics circulating currents for a double-module VSI. In the paper, an analysis of the circulating-current circuits is briefly described. Next, a mathematic model of the single-module output voltage based on the carrier frequency of SPWM is built. On this basis, through mathematic modeling of high-frequency harmonic circulating currents, the formation mechanism and distribution characteristics of circular currents and their influences are studied in detail. Finally, the influences of the OF on the circulating currents are studied by mainly taking an LC-type filter as an example. A theoretical analysis and experimental results demonstrate some important characteristics. First, the carrier phase shifting of the SPWM for each module is the major cause of the SPWM harmonic circulating currents, and the circulating currents are in an odd distribution around n-times the carrier frequency $n{\omega}_s$, where n = 1, 2, 3, ${\ldots}$. Second, the harmonic circular currents do not flow into the parallel system. Third, the OF can effectively suppress the non-circulating part of the high-frequency harmonic currents but is ineffective for the circulation part, and actually reduces system stability.

Threat Classification Schemes for Effective Management based on W-TMS(Wireless-Threat Management System) (W-TMS(Wireless-Threat Management System)에서의 효율적 관리를 위한 위협 분류기법)

  • Seo, Jong-Won;Jo, Je-Gyeong;Lee, Hyung-Woo
    • The Journal of the Korea Contents Association
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    • v.7 no.3
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    • pp.93-100
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    • 2007
  • Internet had spread in all fields with the fast speed during the last 10 years. Lately, wireless network is also spreading rapidly. Also, number of times that succeed attack attempt and invasion for wireless network is increasing rapidly TMS system was developed to overcome these threat on wireless network. Existing TMS system supplies active confrontation mechanism on these threats. However, existent TMS has limitation that new form of attack do not filtered efficiently. Therefor this paper proposes a new method that it automatically compute the threat from the imput packets with vector space model and detect anomaly detection of wireless network. Proposed mechanism in this research analyzes similarity degree between packets, and detect something wrong symptom of wireless network and then classify these threats automatically.

A Method for Eliminating Aiming Error of Unguided Anti-Tank Rocket Using Improved Target Tracking (향상된 표적 추적 기법을 이용한 무유도 대전차 로켓의 조준 오차 제거 방법)

  • Song, Jin-Mo;Kim, Tae-Wan;Park, Tai-Sun;Do, Joo-Cheol;Bae, Jong-sue
    • Journal of the Korea Institute of Military Science and Technology
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    • v.21 no.1
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    • pp.47-60
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    • 2018
  • In this paper, we proposed a method for eliminating aiming error of unguided anti-tank rocket using improved target tracking. Since predicted fire is necessary to hit moving targets with unguided rockets, a method was proposed to estimate the position and velocity of target using fire control system. However, such a method has a problem that the hit rate may be lowered due to the aiming error of the shooter. In order to solve this problem, we used an image-based target tracking method to correct error caused by the shooter. We also proposed a robust tracking method based on TLD(Tracking Learning Detection) considering characteristics of the FCS(Fire Control System) devices. To verify the performance of our proposed algorithm, we measured the target velocity using GPS and compared it with our estimation. It is proved that our method is robust to shooter's aiming error.

Biomimetic approach object detection sensors using multiple imaging (다중 영상을 이용한 생체모방형 물체 접근 감지 센서)

  • Choi, Myoung Hoon;Kim, Min;Jeong, Jae-Hoon;Park, Won-Hyeon;Lee, Dong Heon;Byun, Gi-Sik;Kim, Gwan-Hyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.91-93
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    • 2016
  • From the 2-D image extracting three-dimensional information as the latter is in the bilateral sibeop using two camera method and when using a monocular camera as a very important step generally as "stereo vision". There in today's CCTV and automatic object tracking system used in many medium much to know the site conditions or work developed more clearly by using a stereo camera that mimics the eyes of humans to maximize the efficiency of avoidance / control start and multiple jobs can do. Object tracking system of the existing 2D image will have but can not recognize the distance to the transition could not be recognized by the observer display using a parallax of a stereo image, and the object can be more effectively controlled.

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Characterization of Asymptomatic Megalocytivirus Infection in farmed Rock Fish (Sebastes schlegeli) in Korea (양식 조피볼락 (Sebastes schlegeli)에서 megalocytivirus의 무증상적 감염과 특성 분석)

  • KWON, Woo-Ju;KIM, Young-Chul;YOON, Min-Ji;JEONG, Hyun-Do
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.4
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    • pp.1184-1193
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    • 2015
  • Monitoring for megalocytivirus infection was conducted for ten months from March to December in 2013 in 15 aquatic farms culturing, red sea bream, rock bream, rock fish and black sea bream around Tongyoung coastal area in Korea, to assess spatial and temporal variability of detection prevalence, and to explore possible links with seawater temperature. In nested-PCR targeted major capsid protein (MCP) gene, asymptomatic megalocytivirus infection was detected in the externally healthy farmed fish with a significant prevalence in range from 0 to 58.3% for ten months. Higher prevalence of megalocytivirus (46.7% - 57.1%) was observed in high water temperature season from September to November than that in other months with lower prevalence of 0.0% to 20.0%. Even though an acute infection of megalocytivirus was occurred in rock bream (positive in the first PCR) with high mortality in one of fifteen farms, there was no expansion or transmission of the disease to the rock fish and red sea bream culturing in net cage just proximal to the rock bream cage in which disease outbreaked. Nucleotide sequence analysis of the cloned MCP gene isolated asymptomatically infected rock fish revealed that the megalocytivirus in this study was clustered together with the rock bream iridovirus (RBIV) under the subgroup II of the genus megalocytivirus (Iridoviridae), which is known to be the major megalocytivirus strain in Korea. The typical histopathological signs were not found in the spleen of rock fish asymptomatically infected by megalocytivirus. Experimental infection of rock bream with the spleen homogenate of the rock fish infected asymptomatically did not induce any mortality unlike the homogenate of infected rock bream with hih mortlity. However, these results may suggest that the asymptomatic infection of megalocytivirus in other fish species can be a potential risk threatening aquaculture industries as a transmission factor of megalocytivirus to susceptible fish species, especially rock bream.