• Title/Summary/Keyword: Surveillance Test

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Post-earthquake building safety evaluation using consumer-grade surveillance cameras

  • Hsu, Ting Y.;Pham, Quang V.;Chao, Wei C.;Yang, Yuan S.
    • Smart Structures and Systems
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    • v.25 no.5
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    • pp.531-541
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    • 2020
  • This paper demonstrates the possibility of evaluating the safety of a building right after an earthquake using consumer-grade surveillance cameras installed in the building. Two cameras are used in each story to extract the time history of interstory drift during the earthquake based on camera calibration, stereo triangulation, and image template matching techniques. The interstory drift of several markers on the rigid floor are used to estimate the motion of the geometric center using the least square approach, then the horizontal interstory drift of any location on the floor can be estimated. A shaking table collapse test of a steel building was conducted to verify the proposed approach. The results indicate that the accuracy of the interstory drift measured by the cameras is high enough to estimate the damage state of the building based on the fragility curve of the interstory drift ratio. On the other hand, the interstory drift measured by an accelerometer tends to underestimate the damage state when residual interstory drift occurs because the low frequency content of the displacement signal is eliminated when high-pass filtering is employed for baseline correction.

A Sampling Strategy for Estimating Infection Rate in Vector Mosquitoes of Mosquito-borne Bovine Viral Diseases (소 모기매개 바이러스성 질병의 Vector 감염률 추정을 위한 표본추출 전략)

  • Pak, Son-Il
    • Journal of Veterinary Clinics
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    • v.29 no.1
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    • pp.63-67
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    • 2012
  • Mosquitoes are the vectors of a number of viral diseases in cattle, such as Akabane disease, bovine ephemeral fever, Ainovirus infection, Chuzan virus infection, and Ibaraki disease. These diseases are transmitted from an infected animal to a non-infected host via the blood feeding of the vector. In Korea, the National Veterinary Research and Quarantine Services, Ministry for Food, Agriculture, Forestry and Fisheries is responsible for planning, implementation, laboratory investigations and reporting the results of the national surveillance program for mosquito-borne bovine diseases (MBD). The surveillance program, which was started in 1993, focused to determine the seroprevalence of each disease in cattle herds in space and time. From the epidemiological point of view, more important component of the surveillance program is to monitor infection rates in vectors for specific pathogens because this information is essential for a more precise understanding the dynamics of these diseases in a given environment and for determining risk of transmission. The aim of this study was to describe and compare methods for estimation of vector infection rates using maximum likelihood (MLE) and minimum infection rate in pooled samples. Factors affecting MLE such as number of pools, pooling size and diagnostic test performance are also discussed, assuming some hypothetical sampling scenarios for MBD.

Intelligent Video Surveillance System using RFID Technology (RFID 기술을 이용한 지능형 영상 감시 시스템)

  • An, Tae-Ki;Hong, You-Sik;Song, Young-Jun;Lee, Won-Jae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.1
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    • pp.133-139
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    • 2011
  • lots of problems are emerged on the conventional surveillance systems at urban railway infrastructure. Many projects and research activities have been processing on those problems. Moreover, The interest in Intelligent Video Surveillance System that provides accident prevention and safe driving in urban railway service is dramatically increasing. This paper represents a drawback of existing studies and introduces a new solution using RFID TAG technology to improve the existing problems. Finally, it describes the practice test of automatic notification system based USN(Ubiquitous Sensor Network) for a dangerous situation.

Recommendation of Personalized Surveillance Interval of Colonoscopy via Survival Analysis (생존분석을 이용한 맞춤형 대장내시경 검진주기 추천)

  • Gu, Jayeon;Kim, Eun Sun;Kim, Seoung Bum
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.2
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    • pp.129-137
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    • 2016
  • A colonoscopy is important because it detects the presence of polyps in the colon that can lead to colon cancer. How often one needs to repeat a colonoscopy may depend on various factors. The main purpose of this study is to determine personalized surveillance interval of colonoscopy based on characteristics of patients including their clinical information. The clustering analysis using a partitioning around medoids algorithm was conducted on 625 patients who had a medical examination at Korea University Anam Hospital and found several subgroups of patients. For each cluster, we then performed survival analysis that provides the probability of having polyps according to the number of days until next visit. The results of survival analysis indicated that different survival distributions exist among different patients' groups. We believe that the procedure proposed in this study can provide the patients with personalized medical information about how often they need to repeat a colonoscopy.

A Study on Image Management Behavior according to Self-monitoring, Self-objectification of Profile-based SNS Users (프로필 기반 SNS 사용자의 자기모니터링, 자기대상화 성향에 따른 이미지관리행동 연구)

  • Lee, Hyun-Ok
    • Fashion & Textile Research Journal
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    • v.24 no.2
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    • pp.195-205
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    • 2022
  • This study examines the image management behavior according to self-monitoring, self-objectification of profile-based SNS users. Questionnaires were administered to 313 SNS users including both men and women in their 20s to 30s. The SPSS 25.0 package was utilized for data analysis, which included frequency analysis, factor analysis, Cronbach's ?, t-test, and regression analysis. The study analyzed self-monitoring in 2 groups (high, low), self-objectification for 2 factors (body surveillance, body shame), and image management behavior for 5 factors (fashion oriented, instrumentality, conformity, ostentation, interpersonal disposition). The results revealed: first, self-monitoring groups exhibited significant differences in self-objectification. The higher self-monitoring group was more influenced by body surveillance and body shame compared to the low self-monitoring group. Second, self-objectification had a positive influence on all the factors of image management behavior. Especially, body surveillance demonstrated a high influence on instrumentality and body shame showed a high influence on ostentation. Third, the self-monitoring groups showed significant differences in all the factors of image management behavior. The higher self-monitoring group demonstrated more influence of image management behavior compared to the low self-monitoring group. These results provide useful information in understanding the influence of social media on users' psychological attitude and consciousness toward their body and image management behavior.

Development and Performance Test of TWTA Maintenance System for the Low Altitude Surveillance Radar (저고도 탐지레이더용 진행파관증폭기 정비시스템 개발 및 성능시험 연구)

  • Yoon, In-Chul;Yun, Seok-Jin;Kwon, Jong-Won;Kim, Hie-Sik
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.47 no.6
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    • pp.43-50
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    • 2010
  • In this paper, the TWTA (Traveling Wave Tube Amplifier) maintenance system for the low altitude surveillance Radar was developed using the embedded Linux system, and its superiority was demonstrated through the performance test. Nowadays, the necessity of maintenance system and reliability testing on military equipments has been increasing steadily. In addition, nonlinear characteristics of the maintenance system for the low altitude surveillance Radar are more likely to have serious problems as well as to slow down durability. Therefore, after analyzing characteristics of RF input-output signal and TWTA, we designed interface circuits between the TWTA equipment and the embedded Linux system. The Linux kernel on the system was optimized to improve the efficiency and reliability. And our new TWTA maintenance system was evaluated in the real field. As a result, the proposed system was contented with desired specifications, and demonstrated military's fighting capabilities. Therefore, our novel system will advance military maintenance technology and will help to develop similar equipments.

Verification for the design limit margin of the power device using the HALT reliability test

  • Chang, YuShin
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.11
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    • pp.67-74
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    • 2018
  • The verification for the design limit margin of the power device for the information communication and surveillance systems using HALT(Highly Accelerated Life Test) reliability test is described. The HALT reliability test performs with a step stress method which change condition until the marginal step in a design and development phase. The HALT test methods are the low temperature(cold) step stress test, the high temperature(hot) step stress test, the thermal shock cyclic stess test, and the high temperature destruct limit(hot DL) step stress test. The power device is checked the operating performance during the test. In this paper, the HALT was performed to find out the design limit margin of the power device.

Implementation of Intelligent Moving Target Tracking and Surveillance System Using Pan/Tilt-embedded Stereo Camera System (팬/틸트 탑제형 스테레오 카메라를 이용한 지능형 이동표적 추적 및 감시 시스템의 구현)

  • 고정환;이준호;김은수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.4C
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    • pp.514-523
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    • 2004
  • In this paper, a new intelligent moving target tracking and surveillance system basing on the pan/tilt-embedded stereo camera system is suggested and implemented. In the proposed system, once the face area of a target is detected from the input stereo image by using a YCbCr color model and then, using this data as well as the geometric information of the tracking system, the distance and 3D information of the target are effectively extracted in real-time. Basing on these extracted data the pan/tilted-embedded stereo camera system is adaptively controlled and as a result, the proposed system can track the target adaptively under the various circumstance of the target. From some experiments using 80 frames of the test input stereo image, it is analyzed that standard deviation of the position displacement of the target in the horizontal and vertical directions after tracking is kept to be very low value of 1.82, 1.11, and error ratio between the measured and computed 3D coordinate values of the target is also kept to be very low value of 0.5% on average. From these good experimental results a possibility of implementing a new real-time intelligent stereo target tracking and surveillance system using the proposed scheme is finally suggested.

Background Subtraction based on GMM for Night-time Video Surveillance (야간 영상 감시를 위한 GMM기반의 배경 차분)

  • Yeo, Jung Yeon;Lee, Guee Sang
    • Smart Media Journal
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    • v.4 no.3
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    • pp.50-55
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    • 2015
  • In this paper, we present background modeling method based on Gaussian mixture model to subtract background for night-time video surveillance. In night-time video, it is hard work to distinguish the object from the background because a background pixel is similar to a object pixel. To solve this problem, we change the pixel of input frame to more advantageous value to make the Gaussian mixture model using scaled histogram stretching in preprocessing step. Using scaled pixel value of input frame, we then exploit GMM to find the ideal background pixelwisely. In case that the pixel of next frame is not included in any Gaussian, the matching test in old GMM method ignores the information of stored background by eliminating the Gaussian distribution with low weight. Therefore we consider the stacked data by applying the difference between the old mean and new pixel intensity to new mean instead of removing the Gaussian with low weight. Some experiments demonstrate that the proposed background modeling method shows the superiority of our algorithm effectively.

A Design of Mooring Line for the Buoy-Enabled Underwater Surveillance System (부이형 수중감시 시스템에서 계류라인의 구조 설계)

  • Byun, Yang-Hun;Choi, Bum-Kyu;Oh, Tae-Won
    • The Journal of Korean Institute of Information Technology
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    • v.16 no.12
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    • pp.41-47
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    • 2018
  • The buoy-enabled underwater surveillance system is a device that is installed in a particular sea area and operated for a certain period of tine and moved to another sea area after recovery. In this paper, a mooring method which is applied for a buoy-enabled underwater surveillance system was selected to maintain installation and enure stable operation. Also, the structure of the mooring line was designed. Two-point mooring method was selected considering interference with the communication cable of array-assembly. The composite structure of buoy chain, nylon rope, and anchor chain is designed as the basic component of mooring line. For the verification of design, a numerical simulation and wave tank experiment were performed. Their results were confirmed similarity in test condition. Finally, the mooring lines were designed for the environment of the sea trial location. The mooring line produced by the final design confirmed the stability above the significant wave height considered in the design on the sea trial.