A novel multi-objective tuning strategy for model predictive control in trajectory tracking

Jianqiao Chen,Guofu Tian,Yanbo Fu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.12

Accuracy and efficiency are two important performances of model predictive control in trajectory tracking and they are seriously affected by the control parameters of model predictive control. To make the model predictive control with high accuracy and efficiency simultaneous, the paper proposed a strategy to tune the control parameters for model predictive control. The proposed strategy converts the tuning problem to a multi-objective optimization problem and employs non-dominated sorting genetic algorithm (NSGA-II) to solve it. The proposed strategy is employed to tune the control parameters for a classical model predictive control in a typical trajectory tracking condition. The simulation results show that the comprehensive performances of model predictive controller tuned by the proposed method are better than other tuning methods. The proposed tuning strategy is validated and it can be applied to tune the control parameters for model predictive control in trajectory tracking.

Simulation of the Grain Size Effect in Gas-Sensitive SnO2 Thin Films Using the Oxygen Vacancy Gradient Distribution Model

Jianqiao Liu,Zhaoxia Zhai,Guohua Jin,Yuan Li,Faheema Fairuj Monica,Xuesong Liu 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.1

The model of gradient-distributed oxygen vacancies is utilized in simulatingthe grain size effects of gas-sensitive SnO2 thin films. The distribution profileof oxygen vacancies has a grain size effect and the profile gradient correlatespositively with the radius of the grains. The simulation results show that thegrain size is a fundamental factor dominating the gas-sensing properties ofthin films. The potential barrier height and resistivity have significant grainsize effects when m is between 0.1 and 0.5 nm−1. The size effects on sensorresponse to stimulant gases can be enhanced by increasing the value of m orthe absolute value of α. Two expressions are used to simulate the grain sizeeffect of the sensor response. The expressions act similarly when α < 0.2. The simplified response provides a neat function to quantitatively explain thesensor performance on gases with low partial pressure. Although the accurate response is complicated, it is applicable to theentire concentration range. A small power-law exponent n is calculated from the accurate response expression when a high gasconcentration is employed, illustrating a “saturation effect” of the response.

Optimal design of composite laminates for minimizing delamination stresses by particle swarm optimization combined with FEM

Jianqiao Chen,Wenjie Peng,Junhong Wei,Rui Ge 국제구조공학회 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.4

The present paper addresses the optimal design of composite laminates with the aim of minimizing free-edge delamination stresses. A technique involving the application of particle swarm optimization (PSO) integrated with FEM was developed for the optimization. Optimization was also conducted with the zero-order method (ZOM) included in ANSYS. The semi-analytical method, which provides an approximation of the interlaminar normal stress of laminates under in-plane load, was used to partially validate the optimization results. It was found that optimal results based on ZOM are sensitive to the starting design points, and an unsuitable initial design set will lead to a result far from global solution. By contrast, the proposed method can find the global optimal solution regardless of initial designs, and the solutions were better than those obtained by ZOM in all the cases investigated.

Numeral Description of Grain Size Effects of Tin Oxide Gas-Sensitive Elements and Evaluation of Depletion Layer Width

Jianqiao Liu,Guohua Jin,Zhaoxia Zhai,Faheema Fairuj Monica,Xuesong Liu 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.3

The grain size effects on tin oxide gas-sensitive elements are numerically described by the model of gradient-distributed oxygen vacancies, which extends the receptor function of semiconductors to the condition of inhomogeneous donor density in grains. The sensor resistance and the response to the reducing gas are formulated as functions of the grain size and the depletion layer width. The simulations show good agreement with the experimental results. The depletion layer width is estimated as 4 nm for the undoped SnO2 element, whereas the values are 2 and 7 nm for Sb-doped and Al-doped samples, respectively. The results are experimentally verified by the donor-doped SnO2 thin films, the depletion layer widths of which are evaluated on the basis of the correlation between the electrical resistance and the Sb-doping amount. The location of the Fermi level is found to be a crucial factor that dominates the evaluation results.

Fuzzy reliability analysis of laminated composites

Jianqiao Chen,Junhong Wei,Yurong Xu 국제구조공학회 2006 Structural Engineering and Mechanics, An Int'l Jou Vol.22 No.6

Modified Constraint Scores for Semi-Supervised Feature Selection

Jianqiao Wang,Yuehua Li,Kun Chen 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5

Semi-supervised constraint scores, which utilize both pairwise constraints and the local property of the unlabeled data to select features, achieve comparable performance to the supervised feature selection methods. The local property is characterized without considering the pairwise constraints and these two conditions are introduced independently. However, the pairwise constraints and the local property may contain conflicting information. In this paper, we utilize the conflicting information to improve the local property. Instead of characterizing the local property by all neighbors, samples which do not appear in the cannot-link constraints can be used. A performance indicator, called neighborhood-cannot-link (NC) coefficient, is proposed to measure the improvement of the local property. We use the improved local property and the pairwise constraints to perform semi-supervised constraint scores algorithm. Experiments on several real world data sets demonstrate the effectiveness of the methods.

Research Trend Analysis on Internationalization Policies for Chinese Higher Education

Wu Jianqiao,YoungHwan Kim APEC국제교육협력원 2018 Asia-Pacific Cybereducation Journal Vol.14 No.2

This study is aimed at analyzing the research trends on the internationalization policy of Chinese higher education. Descriptively, it would respectively research the policy change and political reasons thereof, the change of internationalization policies of Chinese university, and the change of the researches on the topic, and uncover the relation between the policies and researches by retrieving the relevant research journals from the academic sources including CNKI, China’s largest academic article database. In order to collect as many articles as possible concerning the research topic, the keyword search in the database was adopted with words expressing the meaning of the topic. In conclusion, internationalization policy of higher education has become an important issue in higher education in China. With the change of the policies, researches focusing on internationalization policy of higher education have increased a lot and have made a new research area in China. After analyzing the research trends, it could be believed that the researches in this area would continue to increase in the future and scholars from the higher education field should pay attention to it.

Fuzzy reliability analysis of laminated composites

Chen, Jianqiao,Wei, Junhong,Xu, Yurong Techno-Press 2006 Structural Engineering and Mechanics, An Int'l Jou Vol.22 No.6

The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatly influenced by the properties of constitutive materials, the laminate structures, and load conditions etc, accompanied by many uncertainty factors. So the reliability study on FRP is an important subject of research. Many achievements have been made in reliability studies based on the probability theory, but little has been done on the roles played by fuzzy variables. In this paper, a fuzzy reliability model for FRP laminates is established first, in which the loads are considered as random variables and the strengths as fuzzy variables. Then a numerical model is developed to assess the fuzzy reliability. The Monte Carlo simulation method is utilized to compute the reliability of laminas under the maximum stress criterion. In the second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of the fact that there may exist a series of states between the failure state and the function state, a fuzzy assumption for the structure state together with the probabilistic assumption for strength parameters is adopted to construct the GFRM of composite materials. By defining a generalized limit state function, the problem is converted to the conventional reliability formula that enables the first-order reliability method (FORM) applicable in calculating the reliability index. Several examples are worked out to show the validity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivity analysis shows that some of the mean values of the strength parameters have great influence on the laminated composites' reliability. The differences resulting from the application of different failure criteria and different fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, and can provide an effective and synthetic method to evaluate the reliability of a system with different types of uncertainty factors.

Optimal design of composite laminates for minimizing delamination stresses by particle swarm optimization combined with FEM

Chen, Jianqiao,Peng, Wenjie,Ge, Rui,Wei, Junhong Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.4

The present paper addresses the optimal design of composite laminates with the aim of minimizing free-edge delamination stresses. A technique involving the application of particle swarm optimization (PSO) integrated with FEM was developed for the optimization. Optimization was also conducted with the zero-order method (ZOM) included in ANSYS. The semi-analytical method, which provides an approximation of the interlaminar normal stress of laminates under in-plane load, was used to partially validate the optimization results. It was found that optimal results based on ZOM are sensitive to the starting design points, and an unsuitable initial design set will lead to a result far from global solution. By contrast, the proposed method can find the global optimal solution regardless of initial designs, and the solutions were better than those obtained by ZOM in all the cases investigated.

Construction of culture intelligence: On-site investigation and suggestion on Chinese teaching to foreigners in China

Wu Jianqiao APEC국제교육협력원 2018 Asia-Pacific Cybereducation Journal Vol.14 No.2

Culture teaching is little included in the practice of teaching Chinese to Speakers of Other Languages, which has lasted for a long time. Taking Chinese teaching in Shaanxi Normal University of China (a splendid university famous for Chinese teaching to foreigners) for example, the explanation and description of basic Chinese language uses is the most important objective in the teaching of reading, speaking, listening and writing, whereas culture teaching is very limited. This results in low motivation for students to learn Chinese, who are then unable to adapt into the local community and culture, and therefore cannot increase their Chinese standards. Based on the theory of culture intelligence firstly put forth by Peterson, one would be influenced by culture intelligence if he studies, learns, and works in a non-native language environment, and culture intelligence is closely related to culture teaching. Students with high culture intelligence could perform better than those without. This thesis is aiming at discussing the present situation of China’s Chinese teaching to foreigners and giving suggestions based on Culture Intelligence Theory. Firstly, it will discuss the concept and values of culture intelligence. After that, it will discuss the present condition of domestic Teaching Chinese as a Foreign Language and the lack of culture elements therein from the perspective of teacher, teaching and students. Finally, it will utilize Culture Intelligence Theory to make suggestions in related areas and explore students' Culture Intelligence cultivation standard as well.