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He Z.,Sichuan Vocational and Technical College | Huang Y.,Wuhan University of Technology | Verpoort F.,Wuhan University of Technology
Acta Chimica Sinica | Year: 2013

The incorporation of a trifluoromethyl (CF3) group can increase chemical and metabolic stability, lipophilicity, and membrane permeability of the molecules. As a consequence, the exploitation of efficient methods to construct chiral trifluoromethylated compounds is a highly significant task. Two strategies are often utilized to synthesize compounds bearing a CF3 group at the chiral center. The first strategy is the transfer of a CF3 group from a reagent. This strategy seems to be straightforward and practical, but direct enantioselective trifluoromethylation remains a challenge, and high enantioselectivities are rarely reached. An alternative strategy is the application of some established asymmetric catalytic reactions by using trifluoromethylated compounds as building blocks, which could provide various chiral trifluoromethylated products in high yields and enantioselectivities under mild conditions. Asymmetric Friedel-Crafts reaction has witnessed rapid development in recent years. Asymmetric Friedel-Crafts reaction using prochiral trifluoromethylated starting materials represents an important method for the access of trifluoromethylated derivatives of chiral aromatic compounds. Since Mikami's group identified that chiral BINOL-derived Ti(IV) complexs could be applied in the asymmetric Friedel-Crafts reaction with fluoral to obtain chiral trifluoromethylated compounds, considerable efforts have been dedicated to utilize other chiral organometallic catalysts (such as chiral Ti, Cu, Zn, Zr, Pd, Y, Yb, Ni, Ca complex, etc.) and chiral organo-catalysts (such as cinchona alkaloids, chiral prolinol ethers, chiral phosphoric acids, etc.) in this type of catalytic reaction. Chiral trifluoromethylated compounds with a CF3-group at a chiral carbon center with, or without any heteroatom substituents were obtained in high yields and enantioselectivities. The components (especially CF3-containing starting material of trifluoromethyl ketones, imines and olefins), conditions and mechanism of the Friedel-Crafts reactions, and the synthetic utilities of Friedel-Crafts adducts are discussed in this review. Finally, the existing problem and limitation of this Friedel-Crafts reaction are summarized, and the key prospect of the chiral CF3-containing product-driven Friedel-Crafts reaction is also described. The aim of this review is to stimulate further developments in this area. © 2013 Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences.


Wang B.,Sichuan Vocational and Technical College
Advanced Materials Research | Year: 2012

Polyhydroximic acid (PHA) with the function of heavy metal flocculant was made by compounding polyacrylamide, hydroxylamine hydrochloride and sodium hydroxide, to observe its effects on the cadmium wastewater disposal under different conditions (pH value, different organic complexing agents EDTA, triammonium citrate, glycocoll, humic acids and turbidity). The present study reaches the following results: (1) PHA has good effects on the removal of Cd2+ in wastewater; for the sample wastewater with a concentration of 25 mg·L-1, the removal rate of Cd2+ can reach 94%; (2) The removal rate of Cd2+ rises with the rise of pH values(4-8); (3) EDTA can obviously inhibit PHA's removal rate of Cd2+; (4) Triammonium citrate can improve PHA's removing ability of Cd2+. (5) Glycocoll and humic acids can obviously enhance the removing of Cd2+; (6) Turbidity-causing materials can promote the removal of Cd2+ and turbidity. © (2012) Trans Tech Publications, Switzerland.


Yin C.,Sichuan Vocational and Technical College
Proceedings - 2015 7th International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2015 | Year: 2015

DRGS is the most widely used calculation of the optimal path in-car systems, which in the process of finding the optimal path, is very convenient. However, due to the limitation of the genetic algorithm, efficiency of the optimal path in the output there are some defects. Based on the improved genetic algorithms, serial number coding model based on turning innovative ways of encoding, in the use of in the process of solving optimal path, analyses and feasibility studies, aims at creating a new genetic algorithm for optimal path planning, and demonstrate its usefulness in terms of convergence. © 2015 IEEE.


Chen Z.,Sichuan Vocational and Technical College
Proceedings - 2015 International Conference on Intelligent Transportation, Big Data and Smart City, ICITBS 2015 | Year: 2015

In coal analysis, there exists high dimensional feature information in the dataset. However, there are several irrelative or redundant features. Feature selection algorithm could select the relative attributes, but it is possible that some important features are deleted. In this paper, we propose hierarchical clustering based logistic regression algorithm. It firstly selects multiple groups of features using random selection, and builds multiple models. After model built, it clusters the models and makes the similar models into one clustering. Finally, we use the logistic regression clustering to complete the forecast work for future dataset. © 2016 IEEE.


Yin C.,Sichuan Vocational and Technical College
Proceedings - 7th International Conference on Intelligent Computation Technology and Automation, ICICTA 2014 | Year: 2015

The problem of vehicle routing optimization is researched, to improve the efficiency of vehicle scheduling. With the increasing complexity of the traffic network, the vehicle will face the interference of accident and congestion, this situation is random and cannot be predicted. The traditional vehicle routing planning model lack of analysis of the interference risk, accurate model cannot be established, the vehicle scheduling operating efficiency is bad. In order to avoid these defects, the vehicle routing optimization method is proposed based on hybrid algorithm. According to the theory of traffic information feedback method, the feedback model of road information is established. It provides basis for vehicle routing optimization. The ant colony algorithm and extreme optimization algorithm are combined, the hybrid algorithm is obtained. According to the theory of hybrid algorithm, the vehicle routing optimization model is constructed, and related vehicle data is input in the model. The vehicle routing optimization processing is realized. The experiment results show that this algorithm can improve the scheduling efficiency, so as to meet the actual demand of traffic management. © 2014 IEEE.


Zhu Y.-J.,Sichuan Vocational and Technical College | Cheng Y.-C.,Sichuan Vocational and Technical College
Dianzi Keji Daxue Xuebao/Journal of the University of Electronic Science and Technology of China | Year: 2012

In order to realize real-time voice processing, a parallel access design based on FPGA is proposed. Low memory space is implemented by distributed CLBs while the high memory space is constructed by the embedded arrays on FPGA. The mapping from logical memory to physical memory is introduced. With the help of dynamical replacement algorithm, the frequently accessed memory block is mapped into low memory space. Our experiment results show that, the dynamic replacement algorithm keeps memory access performance in a suitable range.


Wu X.,Sichuan Vocational and Technical College
Proceedings - 2014 5th International Conference on Intelligent Systems Design and Engineering Applications, ISDEA 2014 | Year: 2014

With the rapid development of economy, the person flow pressure for the station, market, subway and other big public places is very largely to current society. The counting and monitoring of person flow is very important in society management and development, it has great practical significance in the public traffic system safety monitoring, passenger flow forecast, the optimal allocation of resources etc. Traditional person flow estimation method takes the manual counting method, and the efficiency and accuracy are bad. An improved person flow counting method is proposed based on video image processing and on feature point extraction of optical flow, and the person flow monitoring system is designed based on the algorithm, the video image is processed with Harris corner detection, and the angle point information of image is obtained, according to the continuity of the optical flow, the flow counting is obtained. The system design process is presented based on the feature point optical flow. Simulation result shows that the system has good performance in person flow counting estimation and monitoring. © 2014 IEEE.


Rong Z.,Sichuan Vocational and Technical College
Proceedings - 2014 5th International Conference on Intelligent Systems Design and Engineering Applications, ISDEA 2014 | Year: 2014

The existing disaster emergency materials management systems are established based on the traditional design mode, the information processing capabilities are limited by the communication control volume of control system, and the asynchronous / synchronous communication and time delay communication are seldom considered. The information sharing and resource integration capability among cities is low. The multi agent system has the good properties such as distribution, autonomy, coordination and robustness. These properties are taken into consideration in this paper, and the emergency material characteristics and management requirements are analyzed sufficiently. Combing with the distributed collaborative model of artificial intelligence, the agent communication model of blackboard structure is designed. An active blackboard design pattern is taken, and the emergency materials management information system is constructed. The system has good knowledge sharing and asynchronous/synchronous communication mechanism. Experiments show that the system can meet the requirements of emergency materials management effectively, and the operation efficiency is improved greatly, the system structure is easy to be implemented. © 2014 IEEE.


Han W.,Sichuan Vocational and Technical College
International Journal of Multimedia and Ubiquitous Engineering | Year: 2014

The paper presents an evolution of personalized courses based on genetic algorithms (PCEGA). The genetic algorithm are successfully applied in the dynamic update process of the course during the whole learning process. Under this framework of this algorithm, the target user model updates dynamically, and the courses evolve during the process. It provides a good general purpose and scalable framework that addresses the personalized course generation in an online learning environment. © 2014 SERSC.


Wu X.,Sichuan Vocational and Technical College
Proceedings - 2015 7th International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2015 | Year: 2015

With the rapid development of multimedia and network technology, image information resource management and retrieval is increasingly important. In this paper, based on CBIR JPEG image decoding process and its coefficient of compressed domain is studied, and implement in the compressed domain color features and texture features of image retrieval, is proposed in the compressed domain combined color and texture features for image retrieval and layout to develop a practical JPEG image retrieval system. © 2015 IEEE.

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