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Issues and mitigations of wind energy penetrated network:Australian network case study

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1141-1157页

作者： asma aziz Aman Maung Than OO Alex STOJCEVSKI Faculty of Science Engineering and Built EnvironmentSchool of Engineering Geelong Waurn Ponds CampusDeakin University Australia Faculty of Science Engineering and Technology School of Software and Electrical Engineering Swinburne University

Longest geographically connected Australian power system is undergoing an unprecedented transition,under the effect of increased integration of renewable energy systems. This change in generation mix has implications for the whole interconnected system designs, its operational strategies and the regulatory framework. Frequency control policies about real-time balancing of demand and supply is one of the prominent and priority operational challenge requiring urgent attention. This paper reviews the Australian electricity market structure in presence of wind energy and its governance. Various issues related to increased wind generation systems integration are discussed in detail. Currently applied mitigations along with prospective mitigation methods requiring new or improved policies are also discussed. It is concluded that developing prospective frequency regulation ancillary services market desires further encouraging policies from governing authority to keep pace with current grid transition and maintain its security.

关键词： Frequency regulation Inertia Rate of change of frequency Demand response Synchronous condenser

Modeling frequency distributions of tree height, diameter and crown area by six probability functions for open forests of Quercus persica in Iran

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Journal of Forestry Research 2016年第4期27卷 901-906页

作者： Mehrdad Mirzaei Jalal aziz Ali Mahdavi asma Mohammad Rad University of Guilan Sowmeh Sara City GuilanIslamic Republic of Iran Faculty of Natural Resources University of GuilanSowmeh Sara Islamic Republic of Iran Faculty of Agriculture university of Ilam IlamIslamic Republic of Iran Faculty of Natural Resources University of Tehran KarajIslamic Republic of Iran

The prediction of the distribution of quantitative variables in a forest stand is of great interest to forest managers, for the evaluation of forest resources and scheduling of future silvicultural treatments. The aim of this research was to model the distribution of quantitative variables for Quercus persica in open forests in Iran. To investigate the probability distribution of trees in natural stands, 642 trees were selected for measurement using a systematic random sampling method. Selected trees were measured and data were analyzed. Gamma, beta, normal,lognormal, exponential and Weibull probability distributions were fitted to the height distribution of trees. Variables of distribution functions were estimated using the maximum likelihood estimation method. Actual probability and probability which derived from functions was compared using Kolmogorov–Smirnov and Anderson–Darling tests. Beta, Weibull and Weibull probability distributions explained the distributions of tree height, DBH and crown area.

关键词： forests Quercus stands crown canopy Weibull Kolmogorov Darling exponential fitted

Low-voltage ride-through capability improvement of Type-3 wind turbine through active disturbance rejection feedback control-based dynamic voltage restorer

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Clean Energy 2023年第5期7卷 1091-1109页

作者： El Mahfoud Boulaoutaq asma aziz Abdelmounime El Magri Ahmed Abbou Mohamed Ajaamoum Azeddine Rachdy Ibn Zohr University Higher School of Technology Agadir School of Engineering Edith Cowan UniversityJoondalupWAaustralia Hassan II University of Casablanca National School of Technical Education Mohammed V University of Rabat Mohammadia School of Engineering

Disconnections due to voltage drops in the grid cannot be permitted if wind turbines(WTs)contribute significantly to electricity pro-duction,as this increases the risk of production loss and destabilizes the *** mitigate the negative effects of these occurrences,WTs must be able to ride through the low-voltage conditions and inject reactive current to provide dynamic voltage *** paper investigates the low-voltage ride-through(LVRT)capability enhancement of a Type-3 WT utilizing a dynamic voltage restorer(DVR).During the grid voltage drop,the DVR quickly injects a compensating voltage to keep the stator voltage *** paper proposes an active disturbance rejection control(ADRC)scheme to control the rotor-side,grid-side and DVR-side converters in a wind–DVR integrated *** performance of the Type-3 WT with DVR topology is evaluated under various test conditions using MATLAB®/Simulink®.These simulation results are also compared with the experimental results for the LVRT capability performed on a WT emulator equipped with a crowbar and direct current(DC)*** simulation results demonstrate a favourable transient and steady-state response of the Type-3 wind turbine quantities defined by the LVRT codes,as well as improved reactive power support under balanced fault *** the most severe voltage drop of 95%,the stator currents,rotor currents and DC bus voltage are 1.25 pu,1.40 pu and 1.09 UDC,respectively,conforming to the values of the LVRT *** controlled by the ADRC technique significantly increases the LVRT capabilities of a Type-3 doubly-fed induction generator-based WT under symmetrical voltage dip *** setting up ADRC controllers might be challenging,the proposed method has been shown to be extremely effective in reducing all kinds of internal and external disturbances.

关键词： active disturbance rejection controller(ADRC) dynamic voltage restorer(DVR) low-voltage ride-through(LVRT) Type-3 wind turbines(WTs) doubly-fed induction generator(DFIG)

Effects of Tualang honey in modulating nociceptive responses at the spinal cord in offspring of prenatally stressed rats

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Journal of Integrative Medicine 2019年第1期17卷 66-70页

作者： Che Badariah Abd aziz Siti Qusyasyiah Ahmad Suhaimi Hidani Hasim asma Hayati Ahmad Idris Long Rahimah Zakaria Department of Physiology School of Medical Sciences Health Campus Universiti Sains Malaysia School of Health Sciences Health Campus Universiti Sains Malaysia

Objective: This study was done to determine whether Tualang honey could prevent the altered nociceptive behaviour, with its associated changes of oxidative stress markers and morphology of the spinal cord,among the offspring of prenatally stressed ***: Pregnant rats were divided into three groups: control, stress, and stress treated with Tualang honey. The stress and stress treated with Tualang honey groups were subjected to restraint stress from day 11 of pregnancy until delivery. Ten week old male offspring(n = 9 from each group) were given formalin injection and their nociceptive behaviours were recorded. After 2 h, the rats were sacrificed, and their spinal cords were removed to assess oxidative stress activity and morphology. Nociceptive behaviour was analysed using repeated measures analysis of variance(ANOVA), while the levels of oxidative stress parameters and number of Nissl-stained neurons were analysed using a one-way ***: This study demonstrated that prenatal stress was associated with increased nociceptive behaviour, changes in the oxidative stress parameters and morphology of the spinal cord of offspring exposed to prenatal stress; administration of Tualang honey reduced the alteration of these ***: This study provides a preliminary understanding of the beneficial effects of Tualang honey against the changes in oxidative stress and neuronal damage in the spinal cord of the offspring of prenatally stressed rats.

关键词： Prenatal stress Nociceptive responses Tualang honey Spinal cord

Automatic Generation Control of Multigeneration Power System

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Journal of Power and Energy Engineering 2014年第4期2卷 312-333页

作者： asma aziz Amanullah Mto Alex Stojsevski Faculty of Science Engineering and Built Environment Deakin University Geelong Geelong Australia

Load frequency Control (LFC) is used for many years as part of Automatic Generation Control (AGC) in power system around the world. In a mixed power system, it is usual to find an area regulated by hydro generation interconnected to another area regulated by thermal generation or in combination of both. In the following study, performance of AGC for Thermal, Hydro and Thermal turbine based power system is examined, including how frequency bias setting influences AGC response and inadvertent interchange. Control performance analysis of three area interconnected systems is simulated and studied through Matlab Simulink software. Integral square error and Integral time absolute error has been used as performance criterion. It is shown that integral time absolute error (ITAE) as performance index leads to faster optimization of controller gain.

关键词： Automatic Generation Control Performance Index ISE ITAE Discrete Controller

Deep Transfer Learning-Enabled Activity Identification and Fall Detection for Disabled People

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Computers, Materials & Continua 2023年第5期75卷 3239-3255页

作者： Majdy M.Eltahir Adil Yousif Fadwa Alrowais Mohamed K.Nour Radwa Marzouk Hatim Dafaalla asma Abbas Hassan Elnour Amira Sayed A.aziz Manar Ahmed Hamza Department of Computer Science College of Science&Art at MahayilKing Khalid UniversitySaudi Arabia Faculty of Arts and Science Najran UniversitySharourahSaudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Industrial Engineering College of Engineering at AlqunfudahUmm Al-Qura UniversitySaudi Arabia Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Science College of Applied SciencesKing Khalid UniversityMuhayil63772Saudi Arabia Department of Digital Media Faculty of Computers and Information TechnologyFuture University in EgyptNew Cairo11835Egypt Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia

The human motion data collected using wearables like smartwatches can be used for activity recognition and emergency event *** is especially applicable in the case of elderly or disabled people who live self-reliantly in their *** sensors produce a huge volume of physical activity data that necessitates real-time recognition,especially during *** is one of the most important problems confronted by older people and people with movement *** previous techniques were introduced and a few used webcam to monitor the activity of elderly or disabled ***,the costs incurred upon installation and operation are high,whereas the technology is relevant only for indoor ***,commercial wearables use a wireless emergency transmitter that produces a number of false alarms and restricts a user’s *** this background,the current study develops an Improved WhaleOptimizationwithDeep Learning-Enabled Fall Detection for Disabled People(IWODL-FDDP)*** presented IWODL-FDDP model aims to identify the fall events to assist disabled *** presented IWODLFDDP model applies an image filtering approach to pre-process the ***,the EfficientNet-B0 model is utilized to generate valuable feature vector ***,the Bidirectional Long Short Term Memory(BiLSTM)model is used for the recognition and classification of fall ***,the IWO method is leveraged to fine-tune the hyperparameters related to the BiLSTM method,which shows the novelty of the *** experimental analysis outcomes established the superior performance of the proposed IWODL-FDDP method with a maximum accuracy of 97.02%.

关键词： Fall detection disabled people deep learning improved whale optimization assisted living

A Geometrical Characterization of Spatially Curved Roberstion-Walker Space and Its Retractions

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Applied Mathematics 2012年第10期3卷 1153-1160页

作者： Abd El-aziz El-Ahmady El-Bagoury asma Salem Al-Luhaybi Mathematics Department Faculty of Science Taibah University Madinah Saudi Arabia Mathematics Department Faculty of Science Tanta University Tanta Egypt

Our aim in the present article is to introduce and study new types of retractions of closed flat Robertson-Walker W4 model. Types of the deformation retract of closed flat Robertson-Walker W4 model are obtained. The relations between the retraction and the deformation retract of curves in W4 model are deduced. Types of minimal retractions of curves in W4 model are also presented. Also, the isometric and topological folding in each case and the relation between the deformation retracts after and before folding have been obtained. New types of homotopy maps are deduced. New types of conditional folding are presented. Some commutative diagrams are obtained.

关键词： Retraction Deformation Retracts Foldings Flat Robertson-Walker Model

Mycotic Infections in Diabetic Patients in Casablanca

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Journal of Diabetes Mellitus 2019年第3期9卷 146-151页

作者： Annelie Kérékou Siham El aziz Alihonou Dédjan asma Chadli Ahmed Farouqi Endocrinology Metabolism and Nutrition Department CNHU-HKM Cotonou Bénin Endocrinology Diabetology and Metabolic Diseases Department Ibn Rochd University Hospital Center of Casablanca Casablanca Morocco

Introduction: The diabetes constitutes the factor risk of mycotic infections. The pathogenic agents depend on the climate, geography and the migration. The objective of this study is to evaluate the prevalence of the mycotic infections within the hospitalized diabetic patients, to describe their localization and identify the responsible germs. Patients and methods: It is about a descriptive and retrospective study conducted from November 2015 to March 2016 in endocrinology office at CHU Ibn Roch of Casablanca. It was included all diabetic patients hospitalized with whom mycotic infection has been suspected. Results: In total 350 diabetic patients have been hospitalized during the period of research. A mycotic infection has been suspected in 138 patients corresponding to the prevalence of 39.4 percent. The means localizations of mycotic infections were feet (intertrigos: 38.4%), onychomycosis (29%), vulvovaginal (21.7%) and mouth (oral candidiasis: 13.3%). The most frequent pathogenic agents were dermatophytes (Trichophyton rubrum: 61%, Trichophyton mentagrophytes: 6.3%) and Candida albicans (23.1%). The direct test and the culture were negative in 7.3%. Conclusion: One-third of the diabetic patients showed a mycotic infection. The feet, constitute the predilection localization of mycotic infections in the diabetic. The dermatophytes and Candida albicans constitute the most frequent pathogenic agents found in our study.

关键词： Mycotic Infection Diabetes Dermatophytes

Hypoglycemia Controlled by Prednisone in an Occult Insulinoma or a Nesidioblastosis

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Open Journal of Endocrine and Metabolic Diseases 2019年第6期9卷 69-73页

作者： Annelie Kérékou Siham El aziz Alihonou Dédjan asma Chadli Ahmed Farouqi Endocrinology Metabolism and Nutrition Department CNHU-HKM Cotonou Benin Endocrinology Diabetology and Metabolic Diseases Department Ibn Rochd University Hospital Center Casablanca Morocco

Insulinoma is a pancreatic endocrine tumor lower in size than 20 mm in 80% of the cases and his treatment is chirurgical. However, in certain circumstances such as an occult location or circumstances of metastases, medical treatment is called for. Observation: A 29 years old patient with no specific pathological antecedents has presented severe hypoglycemia mainly in the morning. A patient was in a generally good condition. The fasting test revealed an inappropriate secretion of insulin at a venous glycemia of 0.35 g/l;which was corroborated by Turner index and altered glucose insulin index that we calculated. Moreover, the 8 h cortisolemia was normal at 90.13 ng/l, the TSH was normal at 1.44 μui/l, anti-insulin antibodies were negative at 6.7 U/l;the search of hypoglycemic sulfonamides was negative. Morphologically, she had three pancreatic tomodensitometry these were normal. She also had echo-endoscopy which showed a normal pancreas. The surgical exploration with preoperative echo is advised only after surgeon’s assessment when the technical conditions are not put together. The diagnosis of the occult insulinoma or of nesidioblastosis was retained. The medical treatment was retained. Due to the unavailability of diazoxide in our pharmacies and the high cost of analogs of somatostatine, she was provided with prednisone 0.5 mg/kg/24h which was 40 mg/day after common agreement. The evolution was favorable. Conclusion: It should be noticed that medical treatment can be suggested if insulinoma is not localized. This observation proves that the localization of the insulinoma can be unsuccessful. It should also be noticed that our experience is the fourth described in literature, where hypoglycemia in insulinomas is controlled by prednisone.

关键词： Hypoglycemia Insulinoma Nesidioblastosis Prednisone