• Title/Summary/Keyword: 감시 시스템

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Study about the role of the Prevention of School Safety Keeper System (학교안전지킴이의 학교폭력예방에 대한 제도적 고찰 - 전문성과 제약성을 중심으로 -)

  • Gong, Bae Wan
    • Convergence Security Journal
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    • v.13 no.2
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    • pp.3-13
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    • 2013
  • School violence that have occurred recently, showing a tendency to collectivization and diverse types of violence, as well as the quality and increase the damage levels. School violence in the home, school, and social factors, but is caused by the lack of awareness about the violence and the reporting of consciousness due to poor acts of violence indirectly assisted. The only place violence has caused the school to establish the legal and institutional arrangements in order to minimize school violence have no choice but to limit its effectiveness is negligible. The problem of school violence in connection with the problem of juvenile crime prevention and control, and punishment should be made of the complex and layered. Operation and School police system, School safety keeper system, school sheriff system since 2005, each municipality in order to minimize school violence, but have no practical help to limit the visible and symbolic effects. Nonexistent professional staff of the institution or school safety monitors emphasis on monitoring the physical state of the system in the form of 'guards' departure inherently have limitations. Also, to prevent criminal acts or violence in the state is not given special privileges and the appropriate role for the school keeper is a problem with the system. Report no other role can not be expected. Should therefore be preceded by a systematic improvement and training of experts in order to prevent school violence, and home and school, in terms of social support and measures.

Coherent Multiple Target Angle-Tracking Algorithm (코히어런트 다중 표적 방위 추적 알고리즘)

  • Kim Jin-Seok;Kim Hyun-Sik;Park Myung-Ho;Nam Ki-Gon;Hwang Soo-Bok
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.4
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    • pp.230-237
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    • 2005
  • The angle-tracking of maneuvering targets is required to the state estimation and classification of targets in underwater acoustic systems. The Problem of angle-tracking multiple closed and crossing targets has been studied by various authors. Sword et al. Proposed a multiple target an91e-tracking algorithm using angular innovations of the targets during a sampling Period are estimated in the least square sense using the most recent estimate of the sensor output covariance matrix. This algorithm has attractive features of simple structure and avoidance of data association problem. Ryu et al. recently Proposed an effective multiple target angle-tracking algorithm which can obtain the angular innovations of the targets from a signal subspace instead of the sensor output covariance matrix. Hwang et al. improved the computational performance of a multiple target angle-tracking algorithm based on the fact that the steering vector and the noise subspace are orthogonal. These algorithms. however. are ineffective when a subset of the incident sources are coherent. In this Paper, we proposed a new multiple target angle-tracking algorithm for coherent and incoherent sources. The proposed algorithm uses the relationship between source steering vectors and the signal eigenvectors which are multiplied noise covariance matrix. The computer simulation results demonstrate the improved Performance of the Proposed algorithm.

Automatic Detection Approach of Ship using RADARSAT-1 Synthetic Aperture Radar

  • Yang, Chan-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.2
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    • pp.163-168
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    • 2008
  • Ship detection from satellite remote sensing is a crucial application for global monitoring for the purpose of protecting the marine environment and ensuring marine security. It permits to monitor sea traffic including fisheries, and to associate ships with oil discharge. An automatic ship detection approach for RADARSAT Fine Synthetic Aperture Radar (SAR) image is described and assessed using in situ ship validation information collected during field experiments conducted on August 6, 2004. Ship detection algorithms developed here consist of five stages: calibration, land masking, prescreening, point positioning, and discrimination. The fine image was acquired of Ulsan Port, located in southeast Korea, and during the acquisition, wind speeds between 0 m/s and 0.4 m/s were reported. The detection approach is applied to anchoring ships in the anchorage area of the port and its results are compared with validation data based on Vessel Traffic Service (VTS) radar. Our analysis for anchoring ships, above 68 m in length (LOA), indicates a 100% ship detection rate for the RADARSAT single beam mode. It is shown that the ship detection performance of SAR for smaller ships like barge could be higher than the land-based radar. The proposed method is also applied to estimate the ship's dimensions of length and breadth from SAR radar cross section(RCS), but those values were comparatively higher than the actual sizes because of layover and shadow effects of SAR.

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Korea Coast Guard's Human Biological Materials Storage Project for Identifying Bodies Recovered from the Sea: A Model Suggestion (해양변사자 신원확인을 위한 해양경찰의 인체유래물 보관사업 모델제시)

  • Joo, Hyunjung;Choo, Minkyu;Baek, Yoongi;Kim, Namyul;Choi, A-jin;Im, Sonyoung;Lee, Jongnam;Kim, Hyungkyu;Lee, Hanseong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.2
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    • pp.171-178
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    • 2018
  • The ocean is a harsh environment and Korea Coast Guard officers often face the threat of death or going missing in the line of duty. In order to promptly identify unknown bodies during mishaps, Korea Coast Guard Research Center has established an identification system using the DNA of its officers. This collected DNA can also be entombed in National Cemeteries when the remains are not recovered. The storage, disposal and quality control of the materials are overseen by the Governing Committee according to the Enforcement Rules for the Human Biological Materials Storage Project for the Identification of Officers Killed or Gone Missing in Action. Approximately 700 bodies are found per year along the Korean coast. An alternative method should be put in place for when identification through fingerprints and teeth are not applicable due to severe decomposition or partial recovery. We believe it would greatly contribute to helping identify the unknown bodies if the storage project could expand its data to include marine industry workers, relevant researchers and those involved in marine leisure activities.

In-Vitro Thrombosis Detection of Mechanical Valve using Artificial Neural Network (인공신경망을 이용한 기계식 판막의 생체외 모의 혈전현상 검출)

  • 이혁수;이상훈
    • Journal of Biomedical Engineering Research
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    • v.18 no.4
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    • pp.429-438
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    • 1997
  • Mechanical valve is one of the most widely used implantable artificial organs of which the reliability is so important that its failure means the death of patient. Therefore early noninvasive detection is essentially required, though mechanical valve failure with thrombosis is the most common. The objective of this paper is to detect the thrombosis formation by spectral analysis and neural network. Using microphone and amplifier, we measured the sound from the mechanical valve which is attached to the pneumatic ventricular assist device. The sound was sampled by A/D converter(DaqBook 100) and the periodogram is the main algorithm for obtaining spectrum. We made the thrombosis models using pellethane and silicon and they are thrombosis model on the valvular disk, around the sewing ring and fibrous tissue growth across the orifice of valve. The performance of the measurment system was tested firstly using 1 KHz sinusoidal wave. The measurement system detected well 1KHz spectrum as expected. The spectrum of normal and 5 kinds of thrombotic valve were obtained and primary and secondary peak appeared in each spectrum waveform. We find that the secondary peak changes according to the thrombosis model. So to distinguish the secondary peak of normal and thrombotic valve quantatively, 3 layer back propagation neural network, which contains 7, 000 input node, 20 hidden layer and 1 output was employed The trained neural network can distinguish normal and valve with more than 90% probability. As a conclusion, the noninvasive monitoring of implanted mechanical valve is possible by analysing the acoustical spectrum using neural network algorithm and this method will be applied to the performance evaluation of other implantable artificial organs.

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A Fault Detection Method for Solenoid Valves in Urban Railway Braking Systems Using Temperature-Effect-Compensated Electric Signals (도시철도차량 제동장치의 솔레노이드 밸브에 대한 전류기반 고장진단기법 개발)

  • Seo, Boseong;Lee, Guesuk;Jo, Soo-Ho;Oh, Hyunseok;Youn, Byeng D.
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.40 no.9
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    • pp.835-842
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    • 2016
  • In Korea, urban railway cars are typically maintained using the strategy of predictive maintenance. In an effort to overcome the limitations of the existing strategy, there is increased interest in adopting the condition-based maintenance strategy. In this study, a novel method is proposed to detect faults in the solenoid valves of the braking system in urban railway vehicles. We determined the key component (i.e., solenoid valve) that leads to braking system faults through the analysis of failure modes, effects, and criticality. Then, an equivalent circuit model was developed with the compensation of the temperature effect on solenoid coils. Finally, we presented how to detect faults with the equivalent circuit model and current signal measurements. To demonstrate the performance of the proposed method, we conducted a case study using real solenoid valves taken from urban railway vehicles. In summary, it was shown that the proposed method can be effective to detect faults in solenoid valves. We anticipate the outcome from this study can help secure the safety and reliability of urban railway vehicles.

Human Tracking Technology using Convolutional Neural Network in Visual Surveillance (서베일런스에서 회선 신경망 기술을 이용한 사람 추적 기법)

  • Kang, Sung-Kwan;Chun, Sang-Hun
    • Journal of Digital Convergence
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    • v.15 no.2
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    • pp.173-181
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    • 2017
  • In this paper, we have studied tracking as a training stage of considering the position and the scale of a person given its previous position, scale, as well as next and forward image fraction. Unlike other learning methods, CNN is thereby learning combines both time and spatial features from the image for the two consecutive frames. We introduce multiple path ways in CNN to better fuse local and global information. A creative shift-variant CNN architecture is designed so as to alleviate the drift problem when the distracting objects are similar to the target in cluttered environment. Furthermore, we employ CNNs to estimate the scale through the accurate localization of some key points. These techniques are object-independent so that the proposed method can be applied to track other types of object. The capability of the tracker of handling complex situations is demonstrated in many testing sequences. The accuracy of the SVM classifier using the features learnt by the CNN is equivalent to the accuracy of the CNN. This fact confirms the importance of automatically optimized features. However, the computation time for the classification of a person using the convolutional neural network classifier is less than approximately 1/40 of the SVM computation time, regardless of the type of the used features.

Spider Fauna in Mt. Jumbong from Korea (점봉산의 거미상)

  • 이준호;강방훈;박홍현;남궁준;김승태
    • The Korean Journal of Soil Zoology
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    • v.5 no.1
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    • pp.21-32
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    • 2000
  • A faunistic study on the spiders (Arachnida: Araneae) from Mt. Jumbong Kangwon-do was carried out from 1996 to 1999. During the survey period, 144 species of 88 genera belonging to 27 families including 5 undetermined species were identified from 900 collecting individuals. The dominant families were Linyphiidae 21 species; 14.6% of total species), Araneidae (20 species, 13.9%), Theridiidae (16 species, 11.1%), and Salticidae 12 species, 8.3%). The composition of the species of web builders was richer than that of hunters. As for species commonness with adjacent countries, the numbers of common species between Mt. Jumbong and Japan, Mt. Jumbong and China, and Mt. Jumbong and Russia were 15 species (80.4%), 98 species (68.5%), and 48 species (33.6%), respectively. The number of common species among these four regions were 39 species (27.3%). So, the spider species composition in Mt. Jumbong seemed being much similar to those in neighbor countries. An outline of biogeographical distribution of spiders can be summarized as 1 Cosmopolitan species (0.7%), 16 Palearctic species (11.2%), 7 Holarctic species (4.9%), 25 Korean endemic species (17.4%) and no Oriental species. In the spider fauna at Mt. Jumbong, therefore, there are high level of occurrence of Korean endemic species with northern spiders as Palearctic and Holarctic species. The level and direction of man-made development may have negative effect on regional biota.

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Sensing Characteristics of $SnO_{2}$ type CO sensors for combustion exhaust gases monitoring (연소배가스 모니터링을 위한 $SnO_{2}$계 CO센서의 검지특성)

  • Kim, I.J.;Han, S.D.;Lim, H.J.;Son, Y.M.
    • Journal of Sensor Science and Technology
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    • v.6 no.5
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    • pp.369-375
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    • 1997
  • $V_{2}O_{5}/ThO_{2}/Pd$-doped $SnO_{2}$ sensor has a good selectivity and stability to CO at high sensor temperature of about $500^{\circ}C$, and shows rapid response. In particular, many kinds of interference gases, such as $NO_{x}$, $C_{3}H_{8}$, $CH_{4}$ and $SO_{2}$ have been found to give only a slight influence on the sensor selectivity to CO gas sensitivity by doped $V_{2}O_{5}$ (3.0 wt.%). For the sensor we used well-known thick film technological route with $V_{2}O_{5}$(3.0 wt.%), Pd(1.0 wt.%) and $ThO_{2}$(l.5 wt.%) as catalytic materials. In the case of mixed $NO_{x}$-CO gases, as combustion exhaust gas, only CO detection by $SnO_{2}$ type semiconductor sensor is generally very difficult because of $NO_{x}$ interference. The developed sensors can use to measure the exhausting gas of the automobile or the boiler for the Air-to-Fuel ratio control.

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The study of improving the performance of lower direction finding ability due to the interfered phase difference of circular array Antennas (원형배열안테나의 위상간섭에 의한 방향탐지 성능저하 개선연구)

  • Chung, Jae-Woo;Kim, Young-Kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.535-539
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    • 2010
  • This paper include to study DoA(Direction of Arrival) for radio collection and monitoring system. The direction finding calculated by applying the CVDF (Correlation Vector Direction Finding) algorithm for the five circular dipole antenna over V / UHF band. To improve the accuracy of direction finding by applying CVDF algorithm needs to obtain ideal phase difference each antennas. However, a circular array antenna phase difference pattern may be distorted on a specific frequency band or to particular direction. The effect of installing each array antennas circularly and the effect of the interference of center pole (located in the center of a circular array antenna mount) may make the distortion of phase pattern. If you use an active antenna instead of passive antenna to obtain good sensitivity, you would measure the more distortion. This paper propose how to change combination of antennas to measure the phase in real-time and how to use antenna beam patterns for minimizing the degradation phenomena at applying simple CVDF algorithm and increasing the direction finding capability.

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