• 제목/요약/키워드: Topological protection

검색결과 8건 처리시간 0.027초

Retrieval of Non-rigid 3D Models Based on Approximated Topological Structure and Local Volume

  • Hong, Yiyu;Kim, Jongweon
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권8호
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    • pp.3950-3964
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    • 2017
  • With the increasing popularity of 3D technology such as 3D printing, 3D modeling, etc., there is a growing need to search for similar models on the internet. Matching non-rigid shapes has become an active research field in computer graphics. In this paper, we present an efficient and effective non-rigid model retrieval method based on topological structure and local volume. The integral geodesic distances are first calculated for each vertex on a mesh to construct the topological structure. Next, each node on the topological structure is assigned a local volume that is calculated using the shape diameter function (SDF). Finally, we utilize the Hungarian algorithm to measure similarity between two non-rigid models. Experimental results on the latest benchmark (SHREC' 15 Non-rigid 3D Shape Retrieval) demonstrate that our method works well compared to the state-of-the-art.

Effective Coupling of a Topological Corner-state Nanocavity to Various Plasmon Nanoantennas

  • Ma, Na;Jiang, Ping;Zeng, You Tao;Qiao, Xiao Zhen;Xu, Xian Feng
    • Current Optics and Photonics
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    • 제6권5호
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    • pp.497-505
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    • 2022
  • Topological photonic nanocavities are considered to possess outstanding optical performance, and provide new platforms for realizing strong interaction between light and matter, due to their robustness to impurities and defects. Here hybrid plasmonic topological photonic nanocavities are proposed, by embedding various plasmon nanoantennas such as gold nanospheres, cylinders, and rectangles in a topological photonic crystal corner-state nanocavity. The maximum quality factor Q and minimum effective mode volume Veff of these hybrid nanocavities can reach the order of 104 and 10-4 (𝜆/n)3 respectively, and the high figures of merit Q/Veff for all of these hybrid nanocavites are stable and on the order of 105 (𝜆/n)-3. The relative positions of the plasmon nanoantennas will influence the coupling strength between the plasmon structures and the topological nanocavity. The hybrid nanocavity with gold nanospheres possesses much higher Q, but relatively large Veff. The presence of a gold rectangular structure can confine more electromagnetic energy within a smaller space, since its Veff is smallest, although Q is lowest among these structures. This work provides an outstanding platform for cavity quantum electrodynamics and has a wide range of applications in topological quantum light sources, such as single-photon sources and nanolasers.

Development of a structure analytic hierarchy approach for the evaluation of the physical protection system effectiveness

  • Zou, Bowen;Wang, Wenlin;Liu, Jian;Yan, Zhenyu;Liu, Gaojun;Wang, Jun;Wei, Guanxiang
    • Nuclear Engineering and Technology
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    • 제52권8호
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    • pp.1661-1668
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    • 2020
  • A physical protection system (PPS) is used for the protection of critical facilities. This paper proposes a structure analytic hierarchy approach (SAHA) for the hierarchical evaluation of the PPS effectiveness in critical infrastructure. SAHA is based on the traditional analysis methods "estimate of adversary sequence interruption, EASI". A community algorithm is used in the building of the SAHA model. SAHA is applied to cluster the associated protection elements for the topological design of complicated PPS with graphical vertexes equivalent to protection elements.

A Novel Online Multi-section Weighed Fault Matching and Detecting Algorithm Based on Wide-area Information

  • Tong, Xiaoyang;Lian, Wenchao;Wang, Hongbin
    • Journal of Electrical Engineering and Technology
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    • 제12권6호
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    • pp.2118-2126
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    • 2017
  • The large-scale power system blackouts have indicated that conventional protection relays that based on local signals cannot fit for modern power grids with complicated setting or heavily loaded-flow transfer. In order to accurately detect various faulted lines and improve the fault-tolerance of wide-area protection, a novel multi-section weighed fault matching and detecting algorithm is proposed. The real protection vector (RPV) and expected section protection vectors (ESPVs) for five fault sections are constructed respectively. The function of multi-section weighed fault matching is established to calculate the section fault matching degrees between RPV and five ESPVs. Then the fault degree of protected line based on five section fault degrees can be obtained. Two fault detecting criterions are given to support the higher accuracy rate of detecting fault. With the enumerating method, the simulation tests illustrate the correctness and fault-tolerance of proposed algorithm. It can reach the target of 100% accuracy rate under 5 bits error of wide-area protections. The influence factors of fault-tolerance are analyzed, which include the choosing of wide-area protections, as well as the topological structures of power grid and fault threshold.

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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    • 제56권8호
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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.

구면 파라미터기법을 이용한 3차원 메쉬 모델의 워더마킹 알고리즘 (A Watermarking Algorithm of 3D Mesh Model Using Spherical Parameterization)

  • 최기철;김종원;최종욱
    • 정보보호학회논문지
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    • 제18권1호
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    • pp.149-159
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    • 2008
  • 본 논문에서는 구면 파라미터기법을 이용한 3차원 메쉬 모델의 워터마킹 알고리즘을 제안하였다. 구면 파라미터기법은 3차원 데이터 처리에서 광범위하게 응용되는 기법으로서 직교좌표계에서 판단이 불가능한 3차원 메쉬 모델의 꼭지점 좌표의 특성을 구면 파라미터기법을 적용한 후 효과적으로 분석하고 처리할 수 있다. 본 논문에서는 3차원 메쉬 모델의 질량중심을 구면좌표의 원점으로 설정하여 직교좌표계에서 구면좌표계로 변환한 후 구면 파라미터기법을 적용하였다. 3차원 모델의 기하학적 정보와 위상정보의 특성을 구면 모델에서 분석하였으며 꼭지점의 추가와 위상정보의 수정을 통하여 워터마크를 삽입하였다. 제안된 알고리즘은 이동, 스케일링, 회전 등 전형적인 기하학적인 변환에 강인하며 메쉬 순서정렬, 파일 포맷 변환에서도 강인성을 유지하였고 메쉬 세분화에서는 워터마크 정보가 $90{\sim}98%$ 가량 유지됨을 확인하였으며 특히 평활화 공격에서 좋은 성능을 보여주었다.

Characteristics of Interface States in One-dimensional Composite Photonic Structures

  • Zhang, Qingyue;Mao, Weitao;Zhao, Qiuling;Wang, Maorong;Wang, Xia;Tam, Wing Yim
    • Current Optics and Photonics
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    • 제6권3호
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    • pp.270-281
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    • 2022
  • Based on the transfer-matrix method (TMM), we report the characteristics of the interface states in one-dimensional (1D) composite structures consisting of two photonic crystals (PCs) composed of binary dielectrics A and B, with unit-cell configurations ABA (PC I) and BAB (PC II). The dependence of the interface states on the number of unit cells N and the boundary factor x are displayed. It is verified that the interface states are independent of N when the PC has inversion symmetry (x = 0.5). Besides, the composite structures support the formation of interface states independent of the PC symmetry, except that the positions of the interface states will be varied within the photonic band gaps. Moreover, the robustness of the interface states against nonuniformities is investigated by adding Gaussian noise to the layer thickness. In the case of inversion symmetry (x = 0.5) the most robust interface states are achieved, while for the other cases (x ≠ 0.5) interface states decay linearly with position inside the band gap. This work could shed light on the development of robust photonic devices.

FPGA integrated IEEE 802.15.4 ZigBee wireless sensor nodes performance for industrial plant monitoring and automation

  • Ompal, Ompal;Mishra, Vishnu Mohan;Kumar, Adesh
    • Nuclear Engineering and Technology
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    • 제54권7호
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    • pp.2444-2452
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    • 2022
  • The field-programmable gate array (FPGA) is gaining popularity in industrial automation such as nuclear power plant instrumentation and control (I&C) systems due to the benefits of having non-existence of operating system, minimum software errors, and minimum common reason failures. Separate functions can be processed individually and in parallel on the same integrated circuit using FPGAs in comparison to the conventional microprocessor-based systems used in any plant operations. The use of FPGAs offers the potential to minimize complexity and the accompanying difficulty of securing regulatory approval, as well as provide superior protection against obsolescence. Wireless sensor networks (WSNs) are a new technology for acquiring and processing plant data wirelessly in which sensor nodes are configured for real-time signal processing, data acquisition, and monitoring. ZigBee (IEEE 802.15.4) is an open worldwide standard for minimum power, low-cost machine-to-machine (M2M), and internet of things (IoT) enabled wireless network communication. It is always a challenge to follow the specific topology when different Zigbee nodes are placed in a large network such as a plant. The research article focuses on the hardware chip design of different topological structures supported by ZigBee that can be used for monitoring and controlling the different operations of the plant and evaluates the performance in Vitex-5 FPGA hardware. The research work presents a strategy for configuring FPGA with ZigBee sensor nodes when communicating in a large area such as an industrial plant for real-time monitoring.