VIRTUAL PROCESSING OF LASER SURFACE HARDENING ON AUTOBODY DIES

A new method of collision-free path plan integrated in virtual processing is developed to improve the efficiency of laser surface hardening on dies. The path plan is based on the premise of no collision and the optimization object is the shortest path. The optimization model of collision-free path is built from traveling salesman problem （TSP）. Collision-free path between two machining points is calculated in configuration space （C-Space）. Ant colony optimization （ACO） algorithm is applied to TSP of all the machining points to find the shortest path, which is simulated in virtual environment set up by IGRIP software. Virtual machining time, no-collision report, etc, are put out atter the simulation. An example on autobody die is processed in the virtual platform, the simulation results display that ACO has perfect optimization effect, and the method of virtual processing with integration of collision-free optimal path is practical.

Event-driven process execution model for process virtual machine

Current orchestration and choreography process engines only serve with dedicate process languages.To solve these problems,an Event-driven Process Execution Model(EPEM) was developed.Formalization and mapping principles of the model were presented to guarantee the correctness and efficiency for process transformation.As a case study,the EPEM descriptions of Web Services Business Process Execution Language(WS-BPEL) were represented and a Process Virtual Machine(PVM)-OncePVM was implemented in compliance with the EPEM.

Reliability modelling based on dependent two-stage virtual age processes

This paper proposes reliability and maintenance models for systems suffering random shocks arriving according to a non-homogeneous Poisson process.The system degradation process include two stages:from the installation of a new system to an initial point of a defect(normal stage),and then from that point to failure(defective stage),following the delay time concept.By employing the virtual age method,the impact of external shocks on the system degradation process is characterized by random virtual age increment in the two stages,resulting in the corresponding two-stage virtual age process.When operating in the defective state,the system becomes more susceptible to fatigue and suffers from a greater aging rate.Replacement is carried out either on failure or on the detection of a defective state at periodic or opportunistic inspections.This paper evaluates system reliability performance and investigates the optimal opportunistic maintenance policy.A case study on a cooling system is given to verify the obtained results.

Hidden Process Offline Forensic Based on Memory Analysis in Windows

Malicious software programs usually bypass the detection of anti-virus software by hiding themselves among apparently legitimate programs.In this work,we propose Windows Virtual Machine Introspection（WVMI）to accurately detect those hidden processes by analyzing memory data.WVMI dumps in-memory data of the target Windows operating systems from hypervisor and retrieves EPROCESS structures’address of process linked list first,and then generates Data Type Confidence Table（DTCT）.Next,it traverses the memory and identifies the similarities between the nodes in process linked list and the corresponding segments in the memory by utilizing DTCT.Finally,it locates the segments of Windows’EPROCESS and identifies the hidden processes by further comparison.Through extensive experiments,our experiment shows that the WVMI detects the hidden process with high identification rate,and it is independent of different versions of Windows operating system.