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The order of a hidden Markov model (HMM) is an index of the complexity and is closely related to the reachable subspace in the state of the model. When the reachable subspace is not the whole space, there exists a reduced-order quasi hidden Markov model (quasi-HMM), which may not satisfy the nonnegative constraints, equivalent to the original HMM. Such an HMM will be called reachable-space reducible. In this paper, we explore a necessary and sufficient condition for the reachable-space reducible HMM. The condition indicates that if the transition matrix and the observation matrix jointly have a certain structured non-zero pattern, then the HMM is reachable-space reducible. We show that the connection graph of the HMM characterizes the condition. Subsequently, we prove that the HMM satisfying this particular structure always has a reduced-order HMM realization satisfying the nonnegative constraints. Some examples are given to demonstrate our results.

This paper presents the modeling and analysis of the longitudinal dynamic of variable-sweep aircraft. The variable-sweep aircraft have complex nonlinear and time-varying characteristics. To capture the complicated characteristics of variable-sweep aircraft, a systematic modeling method of the longitudinal dynamics is investigated. By using Digital Datcom software, aerodynamic data of the morphing aircraft is obtained; then the nonlinear dynamic models of the variable-sweep aircraft is established. To facilitate future control design, a T-S fuzzy model was constructed based on the nonlinear model. Both models are simulated and analyzed. Comparison verifies the effectiveness of the T-S fuzzy model. The characteristics of the longitudinal dynamic are analyzed based on simulation results.

This paper introduces an intelligent visual surveillance system based on TI multimedia Digital Signal Processor (DSP) TMS320DM642, including hardware platform, software platform and algorithm realization. As the core of this system, DSP communicates with host PC via PCI bus. User can set rules via GUI software. The video input from either analog camera or IP camera can be processed by DM642 in real time. If any event breaks the rules, alarm information will be sent to users. Finally, a shadow suppression algorithm based on HSV color information is introduced to reduce the impact of shadow on motion target detection in the sunshine background. Experimental results show that this system can work well outdoors and the CPU load is low enough to meet the requirements of future work such as recognition and tracking.

Conflict resolution is one of the most challenging tasks in collaborative engineering design. In our previous research, a web-based intelligent collaborative system was developed to address this challenge based on intelligent computational argumentation. However, two important issues were not resolved in that system: priority of participants and self-conflicting arguments. In this paper, we develop two methods for incorporating priorities of participants into the computational argumentation network: 1) weighted summation and 2) re-assessment of strengths of arguments based on priority of owners of the argument using fuzzy logic inference. In addition, we develop a method for detection of self-conflicting arguments. Incorporation of priority of participants and detection of self-conflicting arguments have strengthen the capability of managing intelligent argumentation network for the web-based collaborative engineering design system developed in our previous research.

Modern product design is a very complicated process which involves groups of designers, manufacturers, suppliers, and customer representatives. Conflicts are unavoidable in collaboration among multiple stakeholders, who have different objectives, requirements, and priorities. Unfortunately, current web-based collaborative engineering design systems do not support collaborative conflict resolution. In this paper, we will develop an intelligent computational argumentation model to enable management of a large scale argumentation network, and resolution of conflicts based on argumentation from many participants. A web-based intelligent argumentation tool is developed as a part of a web-based collaborative engineering design system based on the above model to resolve conflicts over the internet by enabling selection of the most favored design alternative in the design argumentation from multiple perspectives in collaborative engineering design.