Stress intensity factors and kink angle of a crack interacting with a circular inclusion under remote mechanical and thermal loadings

A problem of a circular elastic inhomogeneity interacting with a crack under uniform loadings (mechanical tension and heat flux at infinity) is solved. The singular integral equations for edge and temperature dislocation distribution functions are constructed and solved numerically, to obtain the stress intensity factors. The effects of the material property ratio on the stress intensity factor (SIF) are investigated. The computed SIFs are used to predict the kink angle of the crack when the crack grows.     

Asynchronous inter-network interference avoidance for wireless body area networks

This paper considers the internetwork interference problem in environments with multiple wireless body area networks (WBANs). We propose an asynchronous internetwork interference avoidance scheme (abbreviated as AIIA), which is based on the hybrid multiple access of carrier sense multiple access with collision avoidance (CSMA/CA) and time division multiple access (TDMA). In AIIA, the gateway device of each WBAN maintains a table, called an AIIA table, which includes the timing offset and TDMA transmission schedule information corresponding to the interfering WBANs. By referring to the table, the conflicting TDMA schedule can be checked and updated by itself, in asynchronous and distributed manners. Extensive simulations are conducted to demonstrate the feasibility and effectiveness of AIIA.     

Smart seed selection-based effective black box fuzzing for IIoT protocol

The Journal of Supercomputing - Connections of cyber-physical system (CPS) components are gradually increasing owing to the introduction of the Industrial Internet of Things (IIoT). IIoT...     

Analysis of a short interfacial crack from the corner of a rectangular inclusion

A useful method is proposed to analyze a short interfacial crack emanating from the corner of a rectangular inclusion. We first analyze the singular stress field (and the corresponding singularity intensity factor H) without the crack in an infinite medium having the rectangular inclusion. The singular stress field (and the corresponding stress intensity factor K) at the tip of the short interfacial crack lying in the interface of the rectangular inclusion is also analyzed, giving the relation between H and K. With this relation, the stress intensity factor K is easily obtained for the case of a short interfacial crack from the corner of a different rectangular inclusion with different external boundary. This method is based on the assumption that the singular K-field is embedded in another singular H-field, which is much smaller than the specimen geometry. To meet the assumption, it is found here that the eigenfunction corresponding to the next smallest eigenvalue of the singular H-field has to be considered. An example is presented to show the usefulness of the present method, where a short interfacial crack from the corner of a rectangular lead frame in epoxy compound used in electronic packaging is analyzed. It is found that the result of the present method is in good agreement with that of the well-known method.     

Application of a conservation integral to an interface crack interacting with singularities

A mutual integral, which has the conservation property is applied to the problem of an interfacial crack. The stress intensity factors K ₁, K ₂, K ₃ and T-stress for the problem in an infinite medium are easily obtained by using the mutual integral without solving the boundary value problem. In doing so the auxiliary solutions are required and they are taken from the known asymptotic solutions. This method is amenable to numerical evaluation of the stress intensity factors and T-stress if the interfacial crack in a finite medium is considered.     

ExtSFR: scalable file recovery framework based on an Ext file system

Multimedia Tools and Applications - As the technologies based on the Internet of Things, the Cloud, Big Data, and mobile technology have recently become the engine of the next-generation fusion...     

A Novel Approach to Analyzing for Detecting Malicious Network Activity Using a Cloud Computing Testbed

Recent developments have caused the expansion of various cloud computing environments and services. Cloud computing environments have led to research in the areas of data processing, virtual environments, and access control. Information security is the most important research area for these environments security. In this study, we analyzed typical example of network testbeds, which have been used for malicious activity data collection and its subsequent analysis. Further, we propose an effective malicious network application testbed, which is based on a cloud system. We also verified the performance of our new testbed by comparing real malicious activity with the cloud-based testbed results.     

Complex variable method for problems of a laminate composed of multiple isotropic layers

A new method of the analysis of a plate composed of thin layers of isotropic linear elastic material is developed. A general solution for displacement, resultant stress and resultant moment fields is obtained by using the complex function theory. It is proved that the complete solutions of the laminated plate subjected to tractions prescribed on its boundary can be obtained from the sum of solutions for uncoupled plates. Particular attention is devoted to the crack tip field and energy release rate for the laminated plate. A closed form solution for singular fields near the crack tip and the relation between the J-integral and the intensity factors are derived through the complex potential formula. Complete forms of the complex potentials for a crack in an infinite laminate as well as for the singularities such as a point force, a point moment and a dislocation are also obtained. This revised version was published online in August 2006 with corrections to the Cover Date.