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High performance servo motor drives generally consisted of current, velocity, and position control loops. Tuning these controllers to achieve satisfactory and consistent dynamic responses is important. In this paper, a parameter identification and auto-tuning scheme for PMAC servo motor drives is presented. Motor electrical parameters such as resistance and inductances are identified first for current control loop tuning. Then, torque constant and mechanical parameters are identified for velocity and position loop tuning. The experimental results verified that the proposed scheme can estimate parameters with good accuracy. Furthermore, depending on the setting of the tuning process, the auto-tune process can be completed within 1.9 seconds. The control system tuned by the proposed scheme can achieve good dynamic performance.

In this paper, we use the Hilbert-Huang transform (HHT) analysis method to explore the time-frequency characteristics of spike waves for epilepsy symptoms. We obtained a sample of spike I wave and non-spike waves for HHT decomposition using a number of intrinsic mode functions of the Hilbert transform (HT) to determine the instantaneous spectrum, marginal spectrum, and Hilbert energy spectrum. We decomposed a number of intrinsic mode functions, the instantaneous spectrum and the Hilbert energy spectrum and compared the differences between spike and non-spike waves. The analysis results showed that the ratios of the normal wave to the referred total energy for IMF1, IMF2, and the residual function exceeded 10%. Furthermore, the ratios of the energy of the energy for IMF1, IMF2, IMF3 and the residual function of Spike I to their total energy also exceeded 10%. The ratios of the energy of IMF3 in the d band to its referred total energy for the EEG signal without spike wave, and of Spike I waves were 4.72%, and 6.75%, respectively. The ratios of the energy of IMF3 in the d band to its referred total energy for the EEG signal without spike wave is lower than that of the energy of IMF3 in the ν band to its referred total energy for the spike I wave.

Accurate servo drive tuning requires motor electrical and mechanical parameters such as torque constant, moment of inertia, and frictional torque coefficient. In this paper, an observer-based auto-tuning scheme for servo motor drives is presented. The main element in this scheme is a state estimator which generates a motor parameter-related disturbance torque. Following the disturbance estimator, two adaptive controllers are used to adjust the drive inertia and frictional torque to their correct values. The servo control loops are tuned automatically with the parameters identified. Motor torque constant is also identified and used in the disturbance estimator. The experimental results verified that the proposed scheme can accurately identify motor parameters and tune the servo control loops.

To mine popular accessed Web pages items and find out their association rule from the Web server Log database for junior users providing recommendation service. A novel GEP-based algorithm for mining multiple-layers association rules was presented. Firstly, takes generalizing technology as a way to value fitness function in GEP (Gene Expression Programming). Then, relying on the significant self-search function of GEP, the most optional species was evolved. The frequent items and association rules in the next deeper layers can be mined by using traditional support-confidence method in sub-database. The algorithm improves on the frame of traditional association rule mining and uses a new evolutionary algorithm for mining association rules. Finally, the validity and efficiency of the method are presented by the application in the paper.

In this paper, a QuickPass model is proposed to improve bank queuing system based on queuing theory. The current bank queuing system is modeled with M/M/c and analytical approach is adopted to guide optimization strategy. Through adjusted greedy algorithm, the multiple-optimization model is simulated with MATLAB. Simulation result shows that the introduction of QuickPass system considerably reduces the average waiting time of customers both in regular queue and QuickPass queue. Pros and cons are analyzed and further application is discussed in the end.

Service choreography and orchestration are two views of the service compositions. In order to select and compose services correctly, some formal methods and tools are used to model and verify those compositions. Pi calculus is a major theory of process algebra that can be used as the formal basis of service composition. According to analysis result of WS CDL and WS BPEL, PiFF - a formal verification framework based on pi calculus is proposed which can be used to check and validate service composition both from global and local point of views. PiFF constitutes of three parts: mapping, methods and tools. This framework can promise consistency between WS CDL and WS BPEL and guarantee developing of dynamic service composition correctly by concept of weak bisimulation.

A flexible intrusion detection and response system (ID&R) needs to maximize security while minimizing cost and making response automatically. CI/sup 2/D&R, the cost-based intelligent intrusion detection and response system, is proposed, which is originally developed as a facility to deal with network-based attacks and to make effective response automatically and intelligently. The networking environment deployed with the CI/sup 2/D&R consists of two major parts: guard, which runs on the specific guarded host (GH), and spy, which runs in guarded network (GN). The components of the CI/sup 2/D&R are introduced, which include intrusion detection, attack classification, damage analysis, attack path rebuilding, resources automatically safeguarding, calamity recovery, and security officer. The several kinds of data flow in CI/sup 2/D&R are discussed, too. While CI/sup 2/&R is only a prototype, some experimental results are also presented.

After the persistent practice in the 1990's, using "open system" idea to integrate large-scale computer systems has been common practice. The new mechanism based on mobile agent is focused and the core architecture called common agent request broker architecture (CARBA) is established in order to embody intelligent collaboration in the next generation open system ABCBA. Then the extension of ABCBA in nomadic environment and validation of ABCBA openness is discussed. In the end, experiment results are given out.

A real-time CORBA prototype called rtORB is presented. The key components of rtORB are mainly described. A platform dependent layer is introduced to enhance the portability of ORB. The scheduling service proposed in real-time CORBA specification is extended to support dynamic scheduling. An explicit binding model is used to establish predictable communication channel. A delayered real-time POA (portable object adapter) is designed to minimize the overhead of demultiplexing and dispatching incoming requests and to avoid priority inversion. Several methods used to optimize its performance are discussed deeply. The real-time performance experiments show that rtORB is capable of supporting real-time application.

A novel fine-grained QoS control method, which realizes by dynamic end-system resource management in response to network variation, is presented. Firstly, we presented a model called continuous media action from the global viewpoint. Then the relationships and important conclusions between QoS parameters (rate, delay and jitter) and end system parameters (priority, buffer and buffer management) are analyzed. QoS control strategies based on dynamic resource management in end systems are given. Finally, all of the above are confirmed through a series of tests.