• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제18권7호
• /
• pp.1817-1839
• /
• 2024

To solve the problem of insufficient recognition of key nodes in the existing software defect detection process, this paper proposes a key node recognition algorithm based on node expansion degree and improved K-shell position, shortened as SDD_KNR. Firstly, the calculation formula of node expansion degree is designed to improve the degree that can measure the local defect propagation capability of nodes in the software network. Secondly, the concept of improved K-shell position of node is proposed to obtain the improved K-shell position of each node. Finally, the measurement of node defect propagation capability is defined, and the key node recognition algorithm is designed to identify the key function nodes with large defect impact range in the process of software defect detection. Using real software systems such as Nano, Cflow and Tar to design three sets of experiments. The corresponding directed weighted software function invoke networks are built to simulate intentional attack and defect source infection. The proposed SDD_KNR algorithm is compared with the BC algorithm, K-shell algorithm, KNMWSG algorithm and NMNC algorithm. The changing trend of network efficiency and the strength of node propagation force are analyzed to verify the effectiveness of the proposed SDD_KNR algorithm.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
• /
• pp.234-241
• /
• 1999

In this study, an improved 8-node flat shell element is presented for the analysis of shell structure, by combining 8-node membrane element with drilling degree-of-freedom and 8-node plate bending element based on the recently presented technique. Firstly, 8-node membrane element designated as CLM8 is presented in this paper. The element has drilling degree-of.freedom in addition to transitional degree-of-freedom. Therefore the element possesses 3 degrees-of-freedom per each node which as well as the improvement of the element behavior, permits an easy connection to other element with rotational degree-of -freedom. Secondly. 8-node flat shell element was composed by adding 8-node Mindlin plate bending element to the membrane element. The behavior of the introduced plate bending element is further improved by combined use of nonconforming displacement modes, selectively reduced integration scheme and assumed shear strain fields. The element passes in the patch test, doesn't show spurious mechanism and doesn't produce shear locking phenomena. Finally, Numerical examples are presented to show the performance of flat shell element developed in the present study.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제11권8호
• /
• pp.3766-3788
• /
• 2017

A blockchain is an underlying technology and basic infrastructure of the Bitcoin system. At present, blockchains and their applications are developing rapidly. However, the basic research of blockchain technology is still in the early stages. The efficiency and reliability of blockchain communication is one of the research problems that urgently need to be studied and addressed. Existing algorithms may be less feasible for blockchain-based communication because they only consider a single communication factor (node communication capability or node trust degree) and only focus on a single communication performance parameter(communication time or communication reliability). In this paper, to shorten the validation time of blockchain transactions and improve the reliability of blockchain-based communication, we first establish a multi-link concurrent communication model based on trust degree, and then we propose a novel integrated factor communication tree algorithm (IFT). This algorithm comprehensively considers the node communication link number and the node trust degree and selects several nodes with powerful communication capacity and high trust as the communication sources to improve the concurrency and communication efficiency. Simulation results indicate that the IFT algorithm outperforms existing algorithms. A blockchain communication routing scheme based on the IFT algorithm can increase communication efficiency by ensuring communication reliability.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
• /
• pp.63-66
• /
• 2001

In this paper, We propose the new interconnection network which is designed to edge numbering labeling using postorder traversal which can reduce diameter when it has same node number with Hypercube, which can reduce total node numbers considering node degree and diameter on Fibonacci trees and its jump sequence of circulant is Fibonacci numbers. It has a simple (shortest oath)routing algorithm, diameter, node degree. It has a spaning subtree which is Fibonacci tree and it is embedded to Fibonacci tree. It is compared with Hypercube. We improve diameter compared with Hypercube.

• 인터넷정보학회논문지
• /
• 제5권5호
• /
• pp.129-138
• /
• 2004

스위치 노드(switch node)로 구성된 네트워크에서 멀티캐스팅을 위한 트리를 구성하는 것은 NP-complete로 알려진 스타이너 트리 문제(Stainer free problem)로 정형화된다. 현재의 멀티캐스트를 요구하는 서비스들은 대개 대용량의 멀티미디어 데이터를 요구하게 된다. 이러한 서비스들은 텍스트 기반의 서비스에 비해 서비스의 질(Quality of Service)이 아주 중요한 요소가 되고, QoS는 전송에 소요되는 시간에 매우 민감하게 반응한다. 단일 제약을 갖는 멀티캐스트 트리 문제에 적용되는 휴리스틱은 이미 많이 연구되었으나, 노드 연결도 제한과 평균 흡수를 고려하는 다중 제약이 있는 멀티캐스트 트리 문제에 적용되는 휴리스틱에 대한 연구는 없었다. 본 논문에서는 다중 제약을 만족하는 효율적인 멀티캐스트 트리 문제에 적용 가능한 알고리즘을 제안하고, 실험을 통하여 성능을 평가하였다.

• Journal of Electrical Engineering and information Science
• /
• 제3권2호
• /
• pp.151-157
• /
• 1998

Free-space optical interconnection networks can be classified into two types, space variant and space invariant, according to the degree of space variance. In terms of physical implementations, the degree of space variance can be interpreted as the degree of sharing beam steering optics among the nodes of a given network. This implies that all nodes in a totally space-invariant network can share a single beam steering optics to realize the given network topology, whereas, in a totally space variant network, each node requires a distinct beam steering optics. However, space invariant networks require mechanisms for distinguishing the origins of incoming signals detected at the node since several signals may arrive at the same time if the node degree of the network is greater than one. This paper presents a signal source encoding scheme for distinguishing incoming signals efficiently, in terms of the number of detectors at each node or the number of unique wavelengths. The proposed scheme is solved by developing a new parallel genetic algorithm called distributed asynchronous genetic algorithm (DAGA). Using the DAGA, we solved signal distinction schemes for various network sizes of several topologies such as hypercube, the mesh, and the de Brujin.

• 융합보안논문지
• /
• 제23권2호
• /
• pp.3-10
• /
• 2023

웹에 존재하는 악성코드 배포 네트워크에는 악성코드 배포를 위해 핵심 역할을 수행하는 중심 노드가 있다. 이노드를 찾아 차단하면 악성코드 전파를 효과적으로 차단할 수 있다. 본 연구에서는 복잡계 네트워크에서 위험 분석이 적용된 centrality 검색 방법을 제안하였고, 이 방식을 통해 악성코드 배포 네트워크 내에서 핵심노드를 찾는 방법을 소개한다. 그 외에, 정상 네트워크와 악성 네트워트는 in-degree와 out-degree 측면에서 큰 차이가 있고, 네트워크 레이아웃 측면에서도 서로 다르다. 이 특징을 통해 우리는 악성과 정상 네트워크를 분별할 수 있다.

• International journal of advanced smart convergence
• /
• 제8권4호
• /
• pp.169-178
• /
• 2019

Due to the characteristics of an ad hoc network without a control center, self-organization, and flexible topology, the trust evaluation of the nodes in the network is extremely difficult. Based on the analysis of ad hoc networks and the blockchain technology, a blockchain-based node-level trust evaluation model is proposed. The concepts of the node trust degree of the HASH list on the blockchain and the perfect reward and punishment mechanism are adopted to construct the node trust evaluation model of the ad hoc network. According to the needs of different applications the network security level can be dynamically adjusted through changes in the trust threshold. The simulation experiments demonstrate that ad-hoc on-demand distance vector(AODV) Routing protocol based on this model of multicast-AODV(MAODV) routing protocol shows a significant improvement in security compared with the traditional AODV and on-demand multipath distance vector(AOMDV) routing protocols.

• Coupled systems mechanics
• /
• 제5권1호
• /
• pp.59-86
• /
• 2016

This paper deals with the free vibration analysis of a dynamical coupled system: flexible gravity dam- compressible rectangular reservoir. The finite element method is used to compute the natural frequencies and modal shapes of the system. Firstly, the reservoir and subsequently the dam is modeled by classical 8-node elements and the natural frequencies plus modal shapes are calculated. Afterwards, a new 21-node element is introduced and the same procedure is conducted in which an efficient method is employed to carry out the integration operations. Finally, the coupled dam-reservoir system is modeled by solely one 21-node element and the free vibration of dam-reservoir interaction system is investigated. As an important result, it is clearly concluded that the one high-order element treats more precisely than the eight-node elements, since the first one utilizes fifth-degree polynomials to construct the shape functions and the second implements polynomials of degree two.

• 대한기계학회논문집
• /
• 제18권11호
• /
• pp.2922-2931
• /
• 1994

We propose a modified 6-node element, where the sampling point of Gauss quadrature moved in the thickness direction. The modified 6-node element has been applied to static problems and forced motion analyses. In this study, this method is extended to the finite element analysis of the natural frequencies of two dimensional problems. We also propose a modified 16-node element for three dimensional problems, which behaves much like a 20-node element with smaller degree of freedom. The modified 6-node and 16-node elements have been applied to the modal analyses of beams and plates, respectively. The results agree well with the results of the 8-node or 20-node element models.