• Title/Summary/Keyword: Detection algorithms

Search Result 1,876, Processing Time 0.026 seconds

Community Detection using Closeness Similarity based on Common Neighbor Node Clustering Entropy

  • Jiang, Wanchang;Zhang, Xiaoxi;Zhu, Weihua
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.16 no.8
    • /
    • pp.2587-2605
    • /
    • 2022
  • In order to efficiently detect community structure in complex networks, community detection algorithms can be designed from the perspective of node similarity. However, the appropriate parameters should be chosen to achieve community division, furthermore, these existing algorithms based on the similarity of common neighbors have low discrimination between node pairs. To solve the above problems, a noval community detection algorithm using closeness similarity based on common neighbor node clustering entropy is proposed, shorted as CSCDA. Firstly, to improve detection accuracy, common neighbors and clustering coefficient are combined in the form of entropy, then a new closeness similarity measure is proposed. Through the designed similarity measure, the closeness similar node set of each node can be further accurately identified. Secondly, to reduce the randomness of the community detection result, based on the closeness similar node set, the node leadership is used to determine the most closeness similar first-order neighbor node for merging to create the initial communities. Thirdly, for the difficult problem of parameter selection in existing algorithms, the merging of two levels is used to iteratively detect the final communities with the idea of modularity optimization. Finally, experiments show that the normalized mutual information values are increased by an average of 8.06% and 5.94% on two scales of synthetic networks and real-world networks with real communities, and modularity is increased by an average of 0.80% on the real-world networks without real communities.

Experimental and Analytical Study on the Water Level Detection and Early Warning System with Intelligent CCTV (지능형 CCTV를 이용한 수위감지 경보시스템에 대한 실험 및 해석적 연구)

  • Hong, Sangwan;Park, Youngjin;Lee, Hacheol
    • Journal of the Society of Disaster Information
    • /
    • v.10 no.1
    • /
    • pp.105-115
    • /
    • 2014
  • In this research, we developed video analytic algorithms to detect water-level automatically and a system for proactive alarming using intelligent CCTV cameras. We applied these algorithms and a system to test-beds and verified for practical use. We made camera-selection policies and operation plans to keep the detection accuracy high and to optimize the suitability for the ever-changing weather condition, while the environmental factors such as camera shaking and weather condition can affect to detection accuracy. The estimation result of algorithms showed 90% detection accuracy for all CCTV camera types. For water level detection, NIR camera performed great. NIR camera performed over 95% accuracy in day or night, suitable in natural weather condition such as shaking condition, fog, and low light, needs similar installment skills with common cameras, and spends only 15% high cost. As a result, we practically tested water level detection algorithms and operation system based on intelligent CCTV camera. Furthermore, we expect the positive evidences when it is applied for public use.

Performance Evaluation of the Harmonic Parameters for High Impedance Fault Detection in Distribution System (배전계통의 고 임피던스 고장 검출 고조파 변수 성능 평가)

  • Oh, Yong-Taek;Kim, C.J.
    • Proceedings of the KIEE Conference
    • /
    • 1997.07c
    • /
    • pp.883-885
    • /
    • 1997
  • High impedance fault(HIF) is random in its behavior even in a similar environment. The detection of Ire HIF has focused on the development of algorithms based on harmonic, parameters of the arc currents. However, a fact that proper selection of the harmonic parameters, rather than algorithm selection, is more important is shown in this paper by applying three different performance evaluation methods on two HIF detection algorithms using eight harmonic parameters.

  • PDF

A Mechanism for Conflict Detection and Resolution for Service Interaction : Toward IP-based Network Services (IP 기반 융합서비스를 위한 서비스 충돌 감지 및 해결에 대한 연구)

  • Oh, Joseph;Shin, Dong-Min
    • IE interfaces
    • /
    • v.23 no.1
    • /
    • pp.24-34
    • /
    • 2010
  • In the telecommunication system which is based on the existing PSTN(public switched telephone network), feature interaction has been an important research issue in order to provide seamless services to users. Recently, rapid proliferation of IP-based network and the various types of IP media supply services, the feature interaction from the perspective of application services has become a significant aspect. This paper presents conflict detection and resolution algorithms for designing and operating a variety of services that are provided through IP-based network. The algorithms use explicit service interactions to detect conflicts between a new service and registered services. They then apply various rules to reduce search space in resolving conflicts. The algorithms are applied to a wide range of realistic service provision scenarios to validate that it can detect conflicts between services and resolve in accordance with different rule sets. By applying the algorithms to various scenarios, it is observed that the proposed algorithms can be effectively used in operating an IP-based services network.

Design and Implementation of User-oriented Face Detection System for Application Developers (응용개발자를 위한 사용자 중심 얼굴검출 시스템 설계 및 구현)

  • Jang, Dae Sik
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.6 no.4
    • /
    • pp.161-170
    • /
    • 2010
  • This paper provides a novel approach for a user oriented system for face detection system for application developers. Even though there are many open source or commercial libraries to solve the problem of face detection, they are still hard to use because they require specific knowledge on detail algorithmic techniques. The purpose of this paper is to come up with a high-level system for face detection with which users can develop systems easily and even without specific knowledge on face detection theories and algorithms. Important conditions are firstly considered to categorize the large problem space of face detection. The conditions identified here are then represented as expressions so that application developers can use them to express various problems. Once the conditions are expressed by developers, the interpreter proposed take the role to interpret the conditions, find and organize the optimal algorithms to solve the represented problem with corresponding conditions. A proof-of-concept is implemented and some example problems are tested and analyzed to show the ease of use and usability.

Emergency Monitoring System Based on a Newly-Developed Fall Detection Algorithm

  • Yi, Yun Jae;Yu, Yun Seop
    • Journal of information and communication convergence engineering
    • /
    • v.11 no.3
    • /
    • pp.199-206
    • /
    • 2013
  • An emergency monitoring system for the elderly, which uses acceleration data measured with an accelerometer, angular velocity data measured with a gyroscope, and heart rate measured with an electrocardiogram, is proposed. The proposed fall detection algorithm uses multiple parameter combinations in which all parameters, calculated using tri-axial accelerations and bi-axial angular velocities, are above a certain threshold within a time period. Further, we propose an emergency detection algorithm that monitors the movements of the fallen elderly person, after a fall is detected. The results show that the proposed algorithms can distinguish various types of falls from activities of daily living with 100% sensitivity and 98.75% specificity. In addition, when falls are detected, the emergency detection rate is 100%. This suggests that the presented fall and emergency detection method provides an effective automatic fall detection and emergency alarm system. The proposed algorithms are simple enough to be implemented into an embedded system such as 8051-based microcontroller with 128 kbyte ROM.

Efficient Symbol Detection Algorithm for Space-frequency OFDM Transmit Diversity Scheme (공간-주파수 OFDM 전송 다이버시티 기법을 위한 효율적인 심볼 검출 알고리즘)

  • Jung Yun ho;Kim Jae seok
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.30 no.4C
    • /
    • pp.283-289
    • /
    • 2005
  • In this paper, we propose two efficient symbol detection algorithms for space-frequency OFDM (SF-OFDM) transmit diversity scheme. When the number of sub-carriers in SF-OFBM scheme is small, the interference between adjacent sub-carriers may be generated. The proposed algorithms eliminate this interference in a parallel or sequential manlier and achieve a considerable performance improvement over the conventional detection algorithm. The bit error rate (BER) performance of the proposed detection algorithms is evaluated by the simulation. In the case of 2 transmit and 2 receive antennas, at $BER=10^{-4}$ the proposed algorithms achieve the gain improvement of about 3 dB. The symbol detectors with the proposed algorithms are designed in a hardware description language and synthesized to gate-level circuits with the $0.18{\mu}m$ 1.8V CMOS standard cell library. With the division-free architecture, the proposed SF-OFDM-PIC and SF-OFDM-SIC symbol detectors can be implemented using 140k and 129k logic gates, respectively.

Deep Learning-Based User Emergency Event Detection Algorithms Fusing Vision, Audio, Activity and Dust Sensors (영상, 음성, 활동, 먼지 센서를 융합한 딥러닝 기반 사용자 이상 징후 탐지 알고리즘)

  • Jung, Ju-ho;Lee, Do-hyun;Kim, Seong-su;Ahn, Jun-ho
    • Journal of Internet Computing and Services
    • /
    • v.21 no.5
    • /
    • pp.109-118
    • /
    • 2020
  • Recently, people are spending a lot of time inside their homes because of various diseases. It is difficult to ask others for help in the case of a single-person household that is injured in the house or infected with a disease and needs help from others. In this study, an algorithm is proposed to detect emergency event, which are situations in which single-person households need help from others, such as injuries or disease infections, in their homes. It proposes vision pattern detection algorithms using home CCTVs, audio pattern detection algorithms using artificial intelligence speakers, activity pattern detection algorithms using acceleration sensors in smartphones, and dust pattern detection algorithms using air purifiers. However, if it is difficult to use due to security issues of home CCTVs, it proposes a fusion method combining audio, activity and dust pattern sensors. Each algorithm collected data through YouTube and experiments to measure accuracy.

Comparison of Atmospheric River Detection Algorithms in East Asia (동아시아 대기의 강 탐지 알고리즘 비교)

  • Gyuri Kim;Seung-Yoon Back;Yeeun Kwon;Seok-Woo Son
    • Atmosphere
    • /
    • v.33 no.4
    • /
    • pp.399-411
    • /
    • 2023
  • This study compares the three detection algorithms of East Asian summer atmospheric rivers (ARs). The algorithms developed by Guan and Waliser (GW15), Park et al. (P21), and Tian et al. (T23) are particularly compared in terms of the AR frequency, the number of AR events, and the AR duration for the period of 2016-2020. All three algorithms show similar spatio-temporal distributions of AR frequency, centered along the edge of the North Pacific high. The maximum AR frequency gradually shifts northward in early summer as the edge of the North Pacific High expands, and retreats in late summer. However, the detailed pattern and the maximum value differ among the algorithms. When the AR frequency is decomposed into the number of AR events and the AR duration, the AR frequencies detected by GW15 and P21 are equally explained by both factors. However, the number of AR events primarily determine the AR frequency in T23. This difference occurs as T23 utilizes the machine learning algorithm applied to moisture field while GW15 and P21 apply the threshold value to moisture transport field. When evaluating AR-related precipitation, the ARs detected by P21 show the closest relationship with total precipitation in East Asia by up to 60%. These results indicate that AR detection in the East Asian summer is sensitive to the choice of the detection algorithm and can be optimized for the target region.

Performance analysis of automatic target tracking algorithms based on analysis of sea trial data in diver detection sonar (수영자 탐지 소나에서의 해상실험 데이터 분석 기반 자동 표적 추적 알고리즘 성능 분석)

  • Lee, Hae-Ho;Kwon, Sung-Chur;Oh, Won-Tcheon;Shin, Kee-Cheol
    • The Journal of the Acoustical Society of Korea
    • /
    • v.38 no.4
    • /
    • pp.415-426
    • /
    • 2019
  • In this paper, we discussed automatic target tracking algorithms for diver detection sonar that observes penetration forces of coastal military installations and major infrastructures. First of all, we analyzed sea trial data in diver detection sonar and composed automatic target tracking algorithms based on track existence probability as track quality measure in clutter environment. In particular, these are presented track management algorithms which include track initiation, confirmation, termination, merging and target tracking algorithms which include single target tracking IPDAF (Integrated Probabilistic Data Association Filter) and multitarget tracking LMIPDAF (Linear Multi-target Integrated Probabilistic Data Association Filter). And we analyzed performances of automatic target tracking algorithms using sea trial data and monte carlo simulation data.