Power quality enhancement and engineering application with high permeability distributed photovoltaic access to low-voltage distribution networks in Australia

Considering power quality problems such as overvoltage and three-phase unbalance caused by high permeability distributed photovoltaic access in low-voltage distribution networks,this paper proposes a comprehensive control scheme using a static var.generator(SVG),electric energy storage(EES),a phase switching device(PSD)and an intelligent terminal controller.The control strategies of transformer overload,bus over/under voltage,anticountercurrent,storage battery state of charge(SOC)maintenance,and three-phase unbalance are studied.The engineering application in the Greenvale low-voltage distribution networks in Australia with high permeability distributed photovoltaics is discussed.The results show that the intelligent terminal controller is able to improve the power quality of low-voltage distribution networks through coordination with EES,SVG and PSD.

Improved particle swarm optimization based on particles' explorative capability enhancement

Accelerating the convergence speed and avoiding the local optimal solution are two main goals of particle swarm optimization（PSO）. The very basic PSO model and some variants of PSO do not consider the enhancement of the explorative capability of each particle. Thus these methods have a slow convergence speed and may trap into a local optimal solution. To enhance the explorative capability of particles, a scheme called explorative capability enhancement in PSO（ECE-PSO） is proposed by introducing some virtual particles in random directions with random amplitude. The linearly decreasing method related to the maximum iteration and the nonlinearly decreasing method related to the fitness value of the globally best particle are employed to produce virtual particles. The above two methods are thoroughly compared with four representative advanced PSO variants on eight unimodal and multimodal benchmark problems. Experimental results indicate that the convergence speed and solution quality of ECE-PSO outperform the state-of-the-art PSO variants.

An Intelligent Intrusion Detection System in Smart Grid Using PRNN Classifier

Typically,smart grid systems enhance the ability of conventional power system networks as it is vulnerable to several kinds of attacks.These vulnerabil-ities might cause the attackers or intruders to collapse the entire network system thus breaching the confidentiality and integrity of smart grid systems.Thus,for this purpose,Intrusion detection system(IDS)plays a pivotal part in offering a reliable and secured range of services in the smart grid framework.Several exist-ing approaches are there to detect the intrusions in smart grid framework,however they are utilizing an old dataset to detect anomaly thus resulting in reduced rate of detection accuracy in real-time and huge data sources.So as to overcome these limitations,the proposed technique is presented which employs both real-time raw data from the smart grid network and KDD99 dataset thus detecting anoma-lies in the smart grid network.In the grid side data acquisition,the power trans-mitted to the grid is checked and enhanced in terms of power quality by eradicating distortion in transmission lines.In this approach,power quality in the smart grid network is enhanced by rectifying the fault using a FACT device termed UPQC(Unified Power Quality Controller)and thereby storing the data in cloud storage.The data from smart grid cloud storage and KDD99 are pre-pro-cessed and are optimized using Improved Aquila Swarm Optimization(IASO)to extract optimal features.The probabilistic Recurrent Neural Network(PRNN)classifier is then employed for the prediction and classification of intrusions.At last,the performance is estimated and the outcomes are projected in terms of grid voltage,grid current,Total Harmonic Distortion(THD),voltage sag/swell,accu-racy,precision,recall,F-score,false acceptance rate(FAR),and detection rate of the classifier.The analysis is compared with existing techniques to validate the proposed model efficiency.

Exploration of the Path to Improve the Innovative Quality and Ability of College and University Students

The improvement of college and university students'innovative quality and ability is necessary for colleges and universities to carry out the fundamental task of establishing moral education and cultivating innovative talents for the Party and the country.At present,there are several problems in the innovation of college and university students,including imperfect system and mechanism,incomplete integration of resources,insufficient understanding of themselves,and so on.In view of these problems,this study actively explores the path to enhance the innovative quality and ability of college and university students by improving the system and mechanism at the macro level,integrating resources to form synergy at the meso level,and motivating college and university students to engage in the process of ascending at the micro level.

Brief analysis of English teaching in vocational institutes

Nowadays, as the international exchange of China becomes increasingly more and China＇s international status has been greatly improved, cross-cultural communication presents its importance in all walks of our life. In vocational institutes, especially institutes of foreign languages, how to train talented persons who can not only speak English fluently and adapt to the market economy, but also professionals with various skills is the most important task. This paper analyzes the problems existing in English teaching in vocational institutes at present and discusses how to sort them out successfully.

Knowledge graph quality control:A survey

A knowledge graph(KG),a special form of semantic network,integrates fragmentary data into a graph to support knowledge processing and reasoning.KG quality control is important to the utility of KGs.It is essential to investigate KG quality and the parameters influencing KG quality to better understand its quality control.Although many works have been conducted to evaluate the dimensions of KG quality,quality control of the construction process,and enhancement methods for quality,a comprehensive literature review has not been presented on this topic.This paper intends to fill this research gap by presenting a comprehensive survey on the quality control of KGs.First,this paper defines six main evaluation dimensions of KG quality and investigates their correlations and differences.Second,quality control treatments during KG construction are introduced from the perspective of these dimensions of KG quality.Third,the quality enhancement of a constructed KG is described from various dimensions.This paper ultimately aims to promote the research and applications of KGs.

EV charging station with cascaded low-pass filtering scheme-based control of unified power quality conditioner

This paper proposes a cascaded low-pass filter(CLPF)scheme for the control of a unified power quality conditioner(UPQC)installed for enhancing the power quality of an electric vehicle(EV)charging station.With the incorporation of UPQC,the EV charging station draws sinusoidal currents at unity power factor and the supply voltage is maintained at the nominal value at the charger input.In the CLPF scheme,theα-βcomponents of the load current are individually processed through a cascade connection of two LPFs to determine the corresponding fundamental orthogonal components.Based on thus determined components,the instantaneous and peak value and phase angle of the fundamental positive sequence component(FPSC)of the load current are computed.Similarly,the corresponding quantities related to the load and supply voltages are also computed with the CLPF scheme.With the computations related to the load current and supply voltage,the unit voltage templates(UVTs),power factor and fundamental active component(FAC)of the load current are calculated.For the control of shunt compensation,reference currents are generated based on the FAC of the load current and UVTs.Alternately,the control of series compensation is employed with the help of UVTs and peak amplitude of the FPSC of the load voltage.The performance of CLPF scheme-based extraction is compared with that of the earlier reported schemes through simulation and experimental studies.The performance comparison reveals a faster dynamic and more accurate steady-state response with the proposed scheme.The performance analysis of the proposed CLPF scheme-based control of a UPQC deployed at the EV charging station for different operating conditions demonstrates station operation with requisite reactive power compensation and mitigation of voltage sag/swell,and prevention of propagation of harmonic and unbalanced currents into the grid.This results in increased reliability of charger operation,energy savings and increased efficiency of the distribution network.

Enhancing the Quality of Growth

The Chinese economy will continue to be the spotlight for world economic growth China’s GDP will maintain a growth rate of about 8.9 percent in 2012 said the annual economic blue book released by the

Appraisal of the Production-Oriented Approach： An Introduction

The production-oriented approach （POA） has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China （Wen, 2016）. It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team, to formulate the theory of POA and to test its effectiveness in classroom pedagogy （e.g. Wen, 2016, 2015; Yang, 2015; Zhang, 2015）. At the moment, the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community, a one-day symposium was held in Beijing Foreign Studies University on May 15, 2017. The symposium was entitled ＇The first international forum on innovative foreign language education in China： Appraisal of the POA＇. In the forum, leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium, listed in alphabetical order. The collection of articles covers three topics related to the POA： its pedagogical application, its use for teacher training, and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies, University of Toronto, Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University, Australia. He discusses POA in terms of pedagogy, teacher training and research, with both critiques and constructive suggestions. Paul Kei Matsuda is Professor of English and Director of Second Language Writing at Arizona State University, the writed states. He responds to POA from the perspective of an expert researcher and teacher of L2 writing. Charlene Polio is Professor and Associate Chair in the Department of Linguistics ＆ Germanic, Slavic, Asian ＆ African Languages atMichigan State University, the writed states. She conceptualises POA as a useful method to address some issues in pre-service teacher development. Overall, the articles in this section are insightful and reader-friendly. They are not only useful for the development of POA in particular, but may also be valuable to a broad range of researchers as they touch upon pertaining issues, as well as emerging topics, in the field of applied linguistics. We therefore find it necessary to make them accessible to a wide readership.