• Title/Summary/Keyword: connected component analysis

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A Study of Key Node Search in Reconnaissance Surveillance Sensor Networks (감시정찰 센서네트워크에서 중요노드 탐색 연구)

  • Kook, Yoon-Ju;Kang, Ji-Won;Kim, Jeom-Goo;Kim, Kiu-Nam
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.7
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    • pp.1453-1458
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    • 2009
  • Sensor network for the human approach in a difficult area and a wide range of surveillance and the boundaries for the purpose and mission is the utilization significantly. In this paper we searched important nodes from the surveillance reconnaissance sensor network based on the virtual data. we generated data within the sensor's measurement range in the data transmitted from sensor nodes, and used PCA(Principle Component Analysis) for searching key node. If the important sensor node searched, and we can have easy management and establishing security measures when security problems is happened about nodes. This is for the sensor network in terms of effectiveness and cost-effectively and is directly connected with life span.

Analysis, Design and Implementation of Flexible Interlaced Converter for Lithium Battery Active Balancing in Electric Vehicles

  • Dai, Shuailong;Wang, Jiayu;Li, Teng;Shan, Zhifei;Wei, Yewen
    • Journal of Power Electronics
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    • v.19 no.4
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    • pp.858-868
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    • 2019
  • With the widespread use of modern clean energy, lithium-ion batteries have become essential as a more reliable energy storage component in the energy Internet. However, due to the difference in monomers, some of the battery over-charge or over-discharge in battery packs restrict their use. Therefore, a novel multiphase interleaved converter for reducing the inconsistencies of the individual cells in a battery pack is proposed in this paper. Based on the multiphase converter branches connected to each lithium battery, this circuit realizes energy transferred from any cell(s) to any other cell(s) complementarily. This flexible interlaced converter is composed of an improved bi-directional Buck-Boost circuit that is presented with its own available control method. A simulation model based on the PNGV model of fundamental equalization is built with four cells in PSIM. Simulation and experimental results demonstrate that converter and its control achieve simple and fast equalization. Furthermore, a comparison of traditional methods and the HNFABC equalization is provided to show the performance of the converter and the control of lithium-based battery stacks.

Traffic Signal Detection and Recognition Using a Color Segmentation in a HSI Color Model (HSI 색상 모델에서 색상 분할을 이용한 교통 신호등 검출과 인식)

  • Jung, Min Chul
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.4
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    • pp.92-98
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    • 2022
  • This paper proposes a new method of the traffic signal detection and the recognition in an HSI color model. The proposed method firstly converts a ROI image in the RGB model to in the HSI model to segment the color of a traffic signal. Secondly, the segmented colors are dilated by the morphological processing to connect the traffic signal light and the signal light case and finally, it extracts the traffic signal light and the case by the aspect ratio using the connected component analysis. The extracted components show the detection and the recognition of the traffic signal lights. The proposed method is implemented using C language in Raspberry Pi 4 system with a camera module for a real-time image processing. The system was fixedly installed in a moving vehicle, and it recorded a video like a vehicle black box. Each frame of the recorded video was extracted, and then the proposed method was tested. The results show that the proposed method is successful for the detection and the recognition of traffic signals.

Invulnerability analysis of nuclear accidents emergency response organization network based on complex network

  • Wen Chen;Shuliang Zou;Changjun Qiu;Jianyong Dai;Meirong Zhang
    • Nuclear Engineering and Technology
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    • v.56 no.8
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    • pp.2923-2936
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    • 2024
  • Modern risk management philosophy emphasizes the invulnerability of human beings to cope with all kinds of emergencies. The Nuclear Accidents Emergency Response Organization (NAERO) of Nuclear Power Plant (NPP) is the primary body responsible for nuclear accidents emergency response. The invulnerability of the organization to disturbance or attack from internal and external sources is crucial in the completion of its response missions, reduction of severity of accidents, and assurance of public and environmental safety. This paper focused on the NAERO of a certain NPP in China, and applied the complex network theory to construct the network model of the organization. The topological characteristics of the network were analyzed. Four importance evaluation indexes of network nodes including Degree Centrality (DC), Betweeness Centrality (BC), Closeness Centrality (CC) and Eigenvector Centrality (EC), along with Pearson coefficient correlation among the indexes were calculated and analyzed. Size of the Largest Connected Component (LCC) and Network Efficiency were used as measures regarding the invulnerability of the network. Simulation experiments were conducted to assess the invulnerability of network against various attack strategies. These experiments were conducted both in the absence of node protection measures and under protection measures with different node protection rates. This study evaluated the invulnerability of the NAERO network, and provided significant decision-making basis for the enhancement of the network's invulnerability.

Expression analysis of ciliary rootlet coiled coil protein mRNA during Xenopus development

  • Rahman, Md. Mahfujur;Kim, In-Shik;Ahn, Dong-Choon;Cho, Ho-Seong;Kim, Won-Il;Kim, Bumseok;Shin, Gee-Wook;Kwon, Jungkee;Akanda, Rashedunnabi;Park, Byung-Yong
    • Korean Journal of Veterinary Research
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    • v.55 no.3
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    • pp.181-184
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    • 2015
  • Ciliary rootlet coiled coil protein (CROCC), the structural component that originates from the basal body at the proximal end of the ciliary rootlet, plays a crucial role in maintaining the cellular integrity of ciliated cells. In the current study, we cloned Xenopus CROCC and performed the expression analysis. The amino acid sequence of Xenopus laevis was related to those of Drosophila, cow, goat, horse, chicken, mouse and human. Reverse transcription polymerase chain reaction analysis revealed that CROCC mRNA encoding a coiled coil protein was present maternally, as well as throughout early development. In situ hybridization indicated that CROCC mRNA occurred in the animal pole of embryo during gastrulation and subsequently in the presumptive neuroectoderm at the end of gastrulation. At tailbud stages, CROCC mRNA expression was localized in the anterior roof plate of the developing brain, pharyngeal epithelium connected to gills, esophagus, olfactory placode, intestine and nephrostomes of the pronephric kidney. Our study suggests that CROCC may be responsible for control of the development of various ciliated organs.

Analysis of Electrical Accident for Outlet Circuit of Laboratory on ETA (ETA를 통한 연구실험실 콘센트회로의 전기재해 분석)

  • Kim, Doo-Hyun;Kim, Sung-Chul;Park, Jong-Young;Kim, Sang-Chul
    • Journal of the Korean Society of Safety
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    • v.32 no.2
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    • pp.27-33
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    • 2017
  • This study is intended to identify issues on the basis of investigating the actual state of laboratory environment and outlet circuit, and derive end states by expressing sequences from the initiating event of disaster to accident in leakage current, poor contact and overload through ETA(event tree analysis). To this end, this study investigated the actual state of electric equipment of laboratory at universities in all parts of country. And it is shown that most of them are failure in electric work and user negligence in the investigation of actual state. It is found that there is earth fault and defect in wire diameter in the failure of electric work and the problem of partial disconnection due to wire bundling and poor contact in user negligence. Outlet-related component, failure rate and initiating events are composed of a total of 41 initiating events, i.e., 30 internal initiating events and 11 external initiating events. And end states are composed of a total of 15 parts, i.e., 3 electric power parts and 12 safety parts. Earthing class 3 is the most important safety device against leakage current (initiating event). And in case of poor contact, it is necessary for manager to check thoroughly because there is no safety device. In case of overload/overcurrent, when high-capacity equipment is connected, a molded case circuit breaker, safety device, worked. However, in most cases, it is verified that this doesn't work. This study can be utilized as electric equipment safety guide for laboratory safety manager and managers.

Numerical Analysis for Evaluation of Ejection Capacity Relationship of Safety Valves in Pressure Regulating Station(I) - Flow Analysis and Mass Flow Rate Verification of Pressure Regulator - (정압기지내의 안전밸브 분출용량 관계식 검증을 위한 유동해석(I) - 정압기 유동 해석 및 질량 유량 검증 -)

  • Gwon, Hyuk-Rok;Roh, Kyung-Chul;Kim, Young-Seop;Lee, Seong-Hyuk
    • Journal of the Korean Institute of Gas
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    • v.12 no.2
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    • pp.99-104
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    • 2008
  • Gas pressure regulators in pressure regulating station reduce high-pressure gas in a process line to a lower. Gas pressure regulators are not flow control devices, they are used to control delivery pressure only. For the safety of pressure regulating station, it is essential to study flow regime and characteristics of a safety valves that is connected to a pressure regulator. For this, it is necessary to understand flow characteristics and the flow rate of upstream component part such as gas pressure regulators in regulating station. In the present study, numerical analysis of flow characteristics and the mass flow rate of a pressure regulator is conducted under the several inlet, outlet conditions and open rates. Then, the numerical result of the mass flow rate is verified with experimental equation from manufacture of pressure regulator. Consequently, the numerical result is comparatively good agreement with values from experimental equation.

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Advanced analysis of cyclic behaviour of plane steel frames with semi-rigid connections

  • Saravanan, M.;Arul Jayachandran, S.;Marimuthu, V.;Prabha, P.
    • Steel and Composite Structures
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    • v.9 no.4
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    • pp.381-395
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    • 2009
  • This paper presents the details of an advanced Finite Element (FE) analysis of a plane steel portal frame with semi-rigid beam-to-column connections subjected cyclic loading. In spite of several component models on cyclic behaviour of connections presented in the literature, works on numerical investigations on cyclic behaviour of full scale frames are rather scarce. This paper presents the evolution of an FE model which deals comprehensively with the issues related to cyclic behaviour of full scale steel frames using ABAQUS software. In the material modeling, combined kinematic/isotropic hardening model and isotropic hardening model along with Von Mises criteria are used. Connection non-linearity is also considered in the analysis. The bolt slip which happens in friction grip connection is modeled. The bolt load variation during loading, which is a pivotal issue in reality, has been taken care in the present model. This aspect, according to the knowledge of the authors, has been first time reported in the literature. The numerically predicted results using the methodology evolved in the present study, for the cyclic behaviour of a cantilever beam and a rigid frame, are validated with experimental results available in the literature. The moment-rotation and deflection responses of the evolved model, match well with experimental results. This proves that the methodology for evolving the steel frame and connection model presented in this paper is closer to real frame behaviour as evident from the good comparison and hence paves the way for further parametric studies on cyclic behaviour of flexibly connected frames.

An Analysis for the status of Environmental Education in the light of the Ecological Knowledge in Korea (생태학적 지식과 관련된 우리나라 환경교육의 실태 분석)

  • 박진희;장남기
    • Hwankyungkyoyuk
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    • v.13 no.1
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    • pp.65-74
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    • 2000
  • Environmentally literated students and adults should be able to use and apply the basic ecological concepts when considering environmental problems and issues. Because ecology forms the foundation of environmental education, a review of the literatures on the degree of students' understanding for ecological concepts can provide useful insights for environmental educators. The purposes of this study were as follows: first, to analyse the parts connected with ecological knowledge of two environmental education books, ‘environments’(middle school) and ‘environmental science’(high school), second, to investigate the level of understanding on ecological concepts by the use of new developed instrument. The 20 most important ecological concepts from Cherrett(1989) and the important ecological concepts' lists from Hungerford and Volk(1990), Ramsey, Hungerford and Volk(1992), Volk(1993) would be recognized and endorsed by most environmental educators as concepts essential to environmental literacy, We referenced these informations and sequenced ecological knowledge as four main categories(communities, populations, ecosystem, man as a component of the nature systems). We have used it as a criterion in the analysis of teaching materials and the development of a new test instrument($\alpha$=0.81). According to the analysed results, the understanding levels for scales and relationships of communities, populations, ecosystem were high but those for individual concepts and differences were low. By the analysis of Korean High School EE book, ‘environmental science’, learning for some concepts(succession, material cycling, niche etc.) has pointed out as one of problems. Environmental educators must pay a careful attention to the concepts that showed high rates of incorrect answer and this work will contribute toward consolidating the basis of EE and help the accomplishment of the ultimate goals in EE.

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Web Document Transcoding Technique for Small Display Devices (소형 화면 단말기를 위한 웹 문서 변환 기법)

  • Shin, Hee-Sook;Mah, Pyeong-Soo;Cho, Soo-Sun;Lee, Dong-Woo
    • The KIPS Transactions:PartD
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    • v.9D no.6
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    • pp.1145-1156
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    • 2002
  • We propose a web document transcoding technique that translates existing web pages designed for desktop computers into an appropriate form for hand-held devices connected to the wireless internet. By defining a content block based on a visual separation and using it as a minimum unit for analyzing and converting processes, we can get web pages converted more exactly. We also apply the reallocation of the content block and the generation of new index in order to provide convenient interface without left-right scrolling in small screen devices. These methods, compared with existing ways such as text level summary or partial extraction method, can provide efficient navigation and a full recognition of web documents. To gain those transcoding benefits, we propose the Layout-Forming Tag Analysis Algorithm that analyzes structural tags, which motivate visual separation and the Component Grouping Algorithm that extracts the content block. We also classify and rearrange the content block and generate the new index to produce an appropriate form of web pages for small display devices. We have designed and implemented our transcoding system in a proxy server and evaluated the methods and the algorithms through an analysis of transcoded results. Our transcoding system showed a good result on most of popular web pages that have complicated structures.