A two-stage sequential heavy reduction (HR) method, in which the reduction amount was increased both before and after the solidification end, is presented to simultaneously improve the homogeneity and compactness of the continuous casting bloom. With bearing steel GCr15 chosen as the specific research steel, a three-dimensional thermal-mechanical finite element model was developed to simulate and analyze the thermal and mechanical behaviors of the continuous casting bloom during the HR process. In order to ensure the accuracy of the simulation, the constitutive model parameters were derived from the experimental results. The predicted temperature distribution and shell thickness were verified using a thermal infrared camera and nail shooting results, respectively. The real measured relationship between the HR pressure and amount were applied to verify the mechanical model. The explorative application results showed that the quality of the bloom center and compactness of rolled bars have both been significantly improved after the HR was applied.

Swanson's tri-core model and typology of IS innovation is used to analyze Web services as IS innovation. Reconciling theoretical and practical perspectives, we develop a three-layer nestedstage model as a road map for studying Web services innovation. Most current Web services practice is at the first stage as IS technological process innovation (Type 1b). High compatibility, high divisibility, and high customizability are the primary characteristics of Web service (Type 1b), which originate from the innovation invention layer. Perceived communicability, perceived relative advantage, perceived complexity, and financial cost are the secondary characteristics of Web services (Type 1b), which are located at the innovation adoption layer. We propose a readiness model to illustrate the key controllable factors that influence the adoption decision of Web services (Type 1b): innovation awareness readiness, innovation-needs fit readiness, technological skills readiness, and financial resources readiness.

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As the prevailing technique of Software-Defined Networking (SDN), OpenFlow introduces significant programmability, granularity and flexibility for many network applications to effectively manage and process network flows. However, OpenFlow only provides a simple "match-action" paradigm and lacks the function of stateful forwarding for SDN data plane, which limits it to support advanced network applications. Heavily relying on SDN controllers for all state maintenance incurs both scalability and performance issues. In this paper, we propose a novel Stateful Data Plane Architecture (SDPA) for SDN data plane. A co-processing unit, Forwarding Processor (FP), is designed for SDN switches to manage state information through new instructions and state tables. We design and implement an extended OpenFlow protocol to implement the communication between the controller and FP. To demonstrate the practicality and feasibility of our approach, we implement both software and hardware prototypes of SDPA switches, and develop a sample network function chain with stateful firewall, DNS reflection attack defense and NAT applications in one SDPA-based switch. Experimental results show that the SDPA architecture can effectively improve the forwarding efficiency with manageable processing overhead for those applications that need stateful forwarding in SDN-based networks.

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