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Industrial Internet of things (IIoT) deploys a large number of smart devices to obtain industrial data, which will be transmitted to cloud for analysis to improve industrial productivity. The management of large-scale devices is complicated, and it's also a challenge to choose a high-quality cloud service for data analysis as the number of service with similar functions increases. To address these issues, we propose a reliable fog-cloud service solution with blockchain-based fog-cloud architecture. In fog layer, we build a management blockchain between fog servers and design a management method for industrial devices; In cloud layer, we construct a service blockchain between cloud service providers to form an open "service market". Quality of service and reputation based matching algorithm and reputation-based consensus algorithm are designed. The simulation results show correctness and efficiency of algorithms, and validate effectiveness of our proposed solution.

The potential translation of bio-inert polymer scaffolds as bone substitutes is limited by the lack of neovascularization upon implantation and subsequently diminished ingrowth of host bone, most likely resulted from the inability to replicate appropriate endogenous crosstalk between cells. Human umbilical vein endothelial cell-derived decellularized extracellular matrix (HdECM), which contains a collection of angiocrine biomolecules, has recently been demonstrated to mediate endothelial cells(ECs) - osteoprogenitors(OPs) crosstalk. We employed the HdECM to create a PCL (polycaprolactone)/fibrin/HdECM (PFE) hybrid scaffold. We hypothesized PFE scaffold could reconstitute a bio-instructive microenvironment that reintroduces the crosstalk, resulting in vascularized bone regeneration. Following implantation in a rat femoral bone defect, the PFE scaffold demonstrated early vascular infiltration and enhanced bone regeneration by microangiography (μ-AG) and micro-computational tomography (μ-CT). Based on the immunofluorescence studies, PFE mediated the endogenous angiogenesis and osteogenesis with a substantial number of type H vessels and osteoprogenitors. In addition, superior osseointegration was observed by a direct host bone-PCL interface, which was likely attributed to the formation of type H vessels. The bio-instructive microenvironment created by our innovative PFE scaffold made possible superior osseointegration and type H vessel-related bone regeneration. It could become an alternative solution of improving the osseointegration of bone substitutes with the help of induced type H vessels, which could compensate for the inherent biological inertness of synthetic polymers.

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The decay of weakly swirling flows in a type of cross-section-varying pipes was discussed analytically. For laminar swirling flow, the feature of exponential decay was demonstrated. For turbulent swirling flow, in spite of the decay of circulation flux, a necessary condition for local circulation to amplify along downstream was obtained under the Boussinesq's hypothesis.

The dam-break problem is important in the design and management of hydraulic engineering. In order to study the spread of dam-break flow on complicated terrain, three-dimensional numerical simulations of the dam-break flow were carried out using VOF in this paper. The results are agreement with experimental data. The complex flow characteristics flood wave propagation process of three-dimensional dam-break flood are demonstrated, which provides scientific basis for the analysis and prevention of disaster caused by dam destruction.

As one solution to the gradual ossification of the existing networks, network virtualization enables multiple service providers (SPs) to coexist on a shared infrastructure, and it is considered as an integral part of next generation architecture. During the run time, SPs have exclusive rights for the allocated bandwidth resources, which may result in poor performance of bandwidth utilization. In this paper, we introduce a novel bandwidth reuse (BR) mechanism to allow SPs lease their idle bandwidth resources to other SPs as a virtual infrastructure provider (InP). In essence, the BR mechanism is a truthful auction with optimal expected revenue generation, which incentivizes SPs to open up their idle bandwidth significantly. Simulation results demonstrate that the BR mechanism could efficiently generate revenue and improve bandwidth utilization.

Network virtualization has been proposed as a powerful and flexible way to support multiple heterogeneous architectures on a shared infrastructure. A major challenge in this respect lies in the resource allocation problem that allocates the resources of Infrastructure Providers (InPs) among Service Providers (SPs) fairly and efficiently. Because of the complexity in the interaction between InPs and SPs, this problem is more complicated and needs more investigation. This paper introduces an InP-SP-End user (ISE) system model in network virtualization environment, in which we present a bandwidth allocation scheme based on VCG (Vickrey-Clarke-Groves) to maximize the total revenue of SPs by inhibiting selfish action of SPs, and design a Q-learning strategy algorithm in order to obtain optimal bidding strategies for SPs. Simulations and experimental studies demonstrate the effectiveness and the fairness of the proposed scheme, and the convergence of the proposed algorithm.

Nowadays testing plays an important role in software development process. While software testing is expensive and time-consuming, sufficient testing is hard, especially for a distributed system using web services technique in the real circumstance. The development of cloud computing provides us new ideas to solve these testing problems. To address these issues, we propose a framework which integrates cloud computing and performance testing technologies. In this paper, first we present the architecture of the cloud-based performance testing system for web services (CPTS), which is a portable, extensible and easy-to-use framework for generating and submitting test workloads to computing clouds. Then, we show the process how to use CPTS to run a performance test and present the concept of dynamic migration in CPTS. Finally, we present our experiences with CPTS in Amazon EC2. We found that the CPTS allows a user to easily set up and test a web services system on the cloud and improve test effectively.

With the construction of 3G network, value-added services will usher in a new development height for mobile operators. The IVR (Interactive Voice Response) business is one of the great market potential business forms. It becomes particularly important to create a good IVR business market. However, this depends on whether the operator could provide well-qualified quality control system and automatic dial-test mechanism for service providers. Therefore, in consideration of the dial-test difficulties caused by IVR service flow complexity in current IVR systems and based on workflow engine implementing flow operations. This paper analyzed and discussed the IVR work process design, as well as the main configuration files of Os-Workflow, then put forward a visual process-designer idea. And finally the IVR automatic dial-test System is designed

The network management architecture concept and the research issues of the network management architecture are given. Based on TMN logical layer architecture, a cube model of the network management architecture is proposed. The application of the model for ATM network based VPN service management is studied in detail.

After proposed the framework of the VPN service management, the shortage of the current management information modeling methods in the network/service management is analyzed and the advantage of the ODP/UML based modeling method is given. The applying open distributed processing/unified modeling language (ODP/UML) for the management information modeling in the VPN service management is studied in detail. The implementation of the VPN SMS using CORBA is also given.