Symmetry-Based Conflict Detection and Resolution Method towards Web3D-based Collaborative Design

In the process of web3D-based collaborative design, it is necessary to completely prevent operation conflicts among designers due to distributed environments and complex 3D models. Therefore, conflict detection and conflict resolution are of great significance to attain an acceptable result. In order to facilitate effective and smooth design work, a symmetry-based collaborative design framework is proposed using the X3D operation models. Combined considerations cover both models and operations, while different operation strategies are utilized for conflict resolution in web-based collaborative design. The strategy can achieve automatic operation, real-time conflict detection based on dynamically adjustable time, and conflict auto-detection and resolution with designers’ customization. A proof-of-concept system is developed for verification. The proposed resolution shows good performance, scalability and interactivity in a case study

Survey and Research on Continuing Education Curriculum Construction for Primary and Secondary School Teachers

Continuing education curriculum construction is the key work to complete the teachers’ continuing education system, it is also an important part of the teachers’ specialization. This study aims to master the main problems of the current primary and secondary school teachers’ continuing education curriculum construction and put forward the corresponding improvement countermeasures. Research in Yunnan province of China as a case, through the Questionnaire Method, Interview Method and Factors Analysis Method, this study make an thorough analysis on the prominent questions of the curriculum resources informationization level, curriculum structure, curriculum practicability, curriculum management and curriculum evaluation mechanism of the primary and secondary school teachers continuing education curriculums construction. Study found that the curriculum construction should also increase the intensity of curriculum resources informatization, develop diversified curriculum resources, complete six modules, carry out a standardized and scientific management and diversified curriculum evaluation mechanism. Research data and conclusions both enrich the theory of the con-struction of the teachers continuing education curriculum, and also provide a practical reference for the admin-istrative department of education and teacher training institutions to formulate measures

A research method to capture design state based on multi-fuzzy cognitive mapping

Designer thinking has received much attention as an innovative problem-solving approach. However, it is also a vague and unclear activity which can only be studied through the input and output results in a design process. This paper proposes that the visual design state is the external performance of design thinking, which is used to clarify vague design thinking. In this paper, a method for expressing and capturing design states based on multi-fuzzy cognitive mapping is presented. First, an agent model is built to capture the design states, and the weight values of the multi-fuzzy cognitive map matrix are calculated. The tightness of the design state route is then deduced. An example is presented to demonstrate the use of this method, which is able to support the designer with the necessary design resources and an intelligent design environment

Optimal control of power system overload considering energy storage and electrothermal characteristics of transmission lines

To solve the problems of line overload tripping and cascading faults caused by power flow transfer in power systems， an optimal control strategy for grid overload considering energy storage and electrothermal characteristics of transmission lines is proposed. Firstly， the variation of electrothermal characteristics of transmission lines is analyzed. Based on meteorological data from various observation stations covered by transmission corridors in practical power grids， a method for calculating conductor temperatures considering meteorological distribution is formulated to enhance the accuracy of estimating line overload capacity. Furthermore， to minimize the control cost， an optimized control model incorporating energy storage for power system overload is established. The simulated annealing particle swarm optimization algorithm is used to solve the model， swiftly determining the optimal control and adjustment quantities and thereby fully leveraging the energy storage regulation capability and line overload tolerance capacity to effectively prevent cascading faults in the power grid. Finally， the effectiveness of the proposed control method is validated using the improved IEEE 39-node system

Symmetry-Based Conflict Detection and Resolution Method towards Web3D-based Collaborative Design

In the process of web3D-based collaborative design, it is necessary to completely prevent operation conflicts among designers due to distributed environments and complex 3D models. Therefore, conflict detection and conflict resolution are of great significance to attain an acceptable result. In order to facilitate effective and smooth design work, a symmetry-based collaborative design framework is proposed using the X3D operation models. Combined considerations cover both models and operations, while different operation strategies are utilized for conflict resolution in web-based collaborative design. The strategy can achieve automatic operation, real-time conflict detection based on dynamically adjustable time, and conflict auto-detection and resolution with designers’ customization. A proof-of-concept system is developed for verification. The proposed resolution shows good performance, scalability and interactivity in a case study

Motion forecast of intelligent underwater sampling apparatus —— Part II: CFD simulation and experimental results

1971-1979The part II of the paper adopts the steady-state superposition algorithm proposed in Part I to simulate the vertical surfacing motion and the horizontal drift of the intelligent underwater sampling apparatus (IUSA) under sea current, in order to figure out the surfacing time and horizontal recovery range on the surface of the sea. Through dividing the surfacing process into a number of infinitesimal segments, the velocity, fluid force and displacement of the IUSA are obtained by resorting to Computational Fluid Dynamics (CFD) software, and the procedure of pre-treatment, solver and post-treatment of Fluent is presented in detail. Simulation results based on SolidWorks and FLUENT are compared which also show the proposed algorithm can meet the requirements of the motion forecast of the IUSA. Preliminary experimental results in East Lake validate that the theoretical algorithm and the computational method are effective within the allowable error range, which can guide the mission operator to recover the IUSA on the broad sea area

A research method to capture design state based on multi-fuzzy cognitive mapping

Designer thinking has received much attention as an innovative problem-solving approach. However, it is also a vague and unclear activity which can only be studied through the input and output results in a design process. This paper proposes that the visual design state is the external performance of design thinking, which is used to clarify vague design thinking. In this paper, a method for expressing and capturing design states based on multi-fuzzy cognitive mapping is presented. First, an agent model is built to capture the design states, and the weight values of the multi-fuzzy cognitive map matrix are calculated. The tightness of the design state route is then deduced. An example is presented to demonstrate the use of this method, which is able to support the designer with the necessary design resources and an intelligent design environment

Robust variable-depth path following of an under-actuated autonomous underwater vehicle with uncertainties

2543-2551This paper treats the subject of variable-depth path following control of an under-actuated autonomous underwater vehicle (AUV) with multiple uncertainties. The modeling uncertainties of the investigated AUV are composed of inaccurate hydrodynamic coefficients and unknown environmental disturbances. For this uncertain system,  a  nonlinear control law integrating line-of-sight (LOS) guidance with fuzzy sliding mode control (FSMC) algorithm is designed to guarantee global κ-exponentially convergence of path following errors. The LOS guidance in the Serret-Frenet frame is adopted to guide the under-actuated AUV to move towards the curved variable-depth path. The sliding mode control algorithm ensures the stability and the robustness of the designed control law in the presence of multiple uncertainties. The fuzzy logic algorithm is integrated to adjust sliding mode gain in order to weaken chattering. In addition, the angle of attack is considered in the design of dynamics control law to ensure that the under-actuated AUV follows the predefined path with a given resultant speed. Finally, a comparative simulation study illustrates the effectiveness of the designed FSMC algorithm for variable-depth path following of an under-actuated AUV with multiple uncertainties