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Identification of voltage sag source location using S and TT transformed disturbance power

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Journal of Central South University 2013年第1期20卷 83-97页

作者： Hussain Shareef Azah Mohamed ahmad asrul ibrahim Department of Electrical Electronics and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia

An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method proposed in the literature. Unlike in the case of the traditional method, the proposed method first transforms the recorded voltage and current during the sag event to some special features before calculating the new version of disturbance powers. The effectiveness of the proposed method has been verified through simulation and actual data from an industrial power system. The results show that the presented method can correctly detect the location of voltage sag source.

关键词： power quality voltage sag S transform TT transform signal processing

Novel quantum-inspired firefly algorithm for optimal power quality monitor placement

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Frontiers in Energy 2014年第2期8卷 254-260页

作者： Ling Ai WONG Hussain SHAREEF Azah MOHAMED ahmad asrul ibrahim Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia Bangi 43600 Malaysia

The application of a quantum-inspired firefly algorithm was introduced to obtain optimal power quality monitor placement in a power system. The conventional binary firefly algorithm was modified by using quantum principles to attain a faster convergence rate that can improve system performance and to avoid premature convergence. In the optimization process, a multi-objective function was used with the system observability constraint, which is determined via the topological monitor reach area concept. The multi-objective function comprises three functions： number of required monitors, monitor over-lapping index, and sag severity index. The effectiveness of the proposed method was verified by applying the algorithm to an IEEE 118-bus transmission system and by comparing the algorithm with others of its kind.

关键词： quantum-inspired binary firefly algorithm topological monitor reach area power quality

Coordinated Voltage Control in Distribution Network with Renewable Energy based Distributed Generation

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Engineering（科研） 2013年第1期5卷 208-214页

作者： Mohd Khairun Nizam Mohd Sarmin Worawat Nakawiro MohdZamriChe Wanik Mohd FadzilMohd Siam ZahrulFaizi Hussien ahmad asrul ibrahim ahmad Kamil Mat Hussin Green Technology Section TNB Research Malaysia Malaysia Power system research group UniversitiKebangsaan Malaysia Malaysia Smart Grid Section TNB Research Malaysia Malaysia

This paper presentsa voltage control strategy for power distribution systems with interconnected renewable energy based distributed generators (DGs). The control strategy coordinating conventional voltage control devices and reactive power from DG.A mixed-integer nonlinear programming problem was formulated and solved by particle swarm optimization (PSO). The code is written using DigSILENT programming language (DPL) and implemented inside DigSILENT power factory simulation software. All system constraints and operating limits are considered. The optimal power flow based approach can incorporate various uncertainties such as intermittent power characteristics and varying load demand. The proposed method is tested using real distribution network to demonstrate its effectiveness. The merits of the proposed method over the classical local-based control are presented in the simulation results. It is demonstrated that the proposed method is capable of keeping the system voltage within operating limit. Power losses is at the same time is minimized in comparison to the losses using conventional method.

关键词： Photovoltaic Distributed Generation Particle Swarm Optimisation DigSILENT Coordinated Control

Oil Palm Particleboard: Properties and Fungi Susceptibility

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Journal of Renewable Materials 2025年第1期13卷 163-180页

作者： Nur Azreena Idris Madihah ahmad Zairun Aisyah Humaira Alias Zawawi ibrahim Noorshamsiana Abdul Wahab Biomass Technology Unit Engineering and Processing DivisionMalaysian Palm Oil BoardNo.6Persiaran InstitusiBandar Baru BangiKajang43000Malaysia Plant Pathology&Biosecurity Unit Biology Research Division Malaysian Palm Oil BoardNo.6Persiaran InstitusiBandar Baru BangiKajang43000Malaysia

The utilization of oil palm biomass in the production of high-value products has increased *** to the presence of sugars and starches in their tissues,oil palms have an exceptionally low natural resistance to fungi,making them susceptible to *** this study,the properties of particleboard made from oil palmﬁbers,namely empty fruit bunches(EFB),oil palm trunks(OPT),and oil palm fronds(OPF)ﬁbers and its poten-tial for fungal attack were *** chemical composition,spectroscopic characterization,morphological features,and elemental analysis of oil palm biomassﬁbers were identiﬁed and thoroughly *** mechan-ical properties and dimensional stability of the boards were assessed based on Japanese Industrial Standards(JIS)and American National Standards Institute(ANSI)*** density,strength,and moisture resistance of particleboard made from OPTﬁbers may vary from those made from OPF and EFB due to inherent changes in chemical composition andﬁber *** differences have an impact on the overall performance of the *** on the ANOVA and Tukey’s test results,signiﬁcant differences in elasticity properties were observed mainly between OPT and otherﬁbers,while bending strength revealed notable differences between various pairs of *** evaluation also highlighted variations in dimensional stability and water absorption ***,bending strength properties did not demonstrate any signiﬁcant *** the fungi test,fungal activity on the boards was observed over a two-week period in a controlled *** study revealed that oil palm-based particleboard exhibited susceptibility to fungal attacks,particularly from Aspergillus sp.,Trichoderma sp.,and Paecilomyces ***ﬁndings highlight the necessity for additional treatments to control or prevent fungal growth,thereby enhancing the commercial value of the particleboards.

关键词： Particleboard medium densityﬁberboard(MDF) empty fruit bunches(EFB) oil palm trunks(OPT) and oil palm fronds(OPF)

Potable Water under Pressure: Effects of the Syrian Crisis and Recent Drought on Northwest Syria

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Journal of Water Resource and Protection 2025年第1期17卷 1-13页

作者： Omar Atik Anas Alkaddour ibrahim Mahmoud Khalid Al Hasan ahmad Nabhan Hani Jazieh Anisha Nijhawan Francesca Pianosi Shafak Organization Gaziantep Trkiye Cara Organization London UK Global Communities Organization Gaziantep Trkiye School of Civil Aerospace and Design Engineering University of Bristol Bristol UK

The study investigates the impact of the Syrian crisis and the recent drought on the potable water situation in Northwest Syria, comparing various aspects of water availability and quality before and after 2011. 380 key-informants were surveyed, including water-well owners, well-digging companies, water-trucking suppliers, agricultural pharmacies, and service offices within local councils. The surveys covered all nine districts in northwestern Syria across the Aleppo and the Idleb governorates. The survey findings reveal significant shifts in water sources, an almost halving in water availability and per capita consumption, and a notable decrease in water quality. Coping mechanisms include random well drilling and reduced hygiene practices. Water pumping stations face challenges with functionality, and there is a shift towards clean energy sources, particularly solar energy. Challenges identified by the survey respondents include drought, fuel costs, and damaged water networks. The study highlights the urgency of addressing the potable water crisis in Northwest Syria and suggests specific interventions to enhance water sustainability and governance.

关键词： Water Potable Crisis Drought Northwest Syria

More than a simple egg:Underlying mechanisms of cold tolerance in avian embryos

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Avian Research 2023年第2期14卷 267-280页

作者： ibrahim M.ahmad Dongming Li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang050024China Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuang050024China

Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low *** being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain largely *** gain a better understanding of this phenomenon and the coping mechanisms involved,we reviewed the literature on severe cold tolerance in embryos of both wild and domestic *** found that embryos of different bird orders exhibit tolerance to severe cold during their *** response to cold stress,embryos slow down their heartbeat rates and *** severe cold temperatures,embryos can suspend these processes,entering a torpid-like state of cardiac *** compensate for these developmental delays,embryos extend their regular incubation *** on their embryonic age,embryos of all bird species can tolerate acute severe cold regimes;only a few tolerate chronic severe cold *** also discussed various extrinsic and intrinsic factors that affect the tolerance of bird embryos to low temperatures before and after *** tolerance appears to be a heritable trait shared by wild and domestic embryos of all bird classes,regardless of egg size or development(altricial/precocial).Driven by environmental variability,cold tolerance in avian embryos is an optimal physiological and ecological strategy to mitigate the adverse effects of cold conditions on their development in response to fluctuating environmental temperatures.

关键词： Acute cold tolerance Avian embryo Chronic cold tolerance Embryonic development Hatching success Incubation period

Microwave-assisted solvent extraction of castor oil from castor seeds

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2516-2522页

作者： Nur Atirah ibrahim Muhammad Abbas ahmad Zaini Centre of Lipids Engineering & Applied Research (CLEAR) Ibnu-Sina Institute for Scientific & Industrial Research Universiti Teknologi Malaysia 81310 UTM Johor Bahru Johor Malaysia School of Chemical & Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia

This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) *** process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.

关键词： Castor seed Castor oil Dielectric properties Microwave-assisted solvent extraction Oxidation stability

Migration of existing software systems to mobile computing platforms:a systematic mapping study

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Frontiers of Computer Science 2021年第2期15卷 13-37页

作者： ibrahim ALSEADOON Aakash ahmad Adel ALKHALIL Khalid SULTAN College of Computer Science and Engineering University of Ha’ilHa’il2440Saudi Arabia College of Engineering and Applied Sciences American University of KuwaitSalmiya13034Kuwait

Mobile computing has fast emerged as a pervasive technology to replace the old computing paradigms with portable computation and context-aware *** software systems can be migrated(while preserving their data and logic)to mobile computing platforms that support portability,context-sensitivity,and enhanced *** recent years,some research and development efforts have focused on a systematic migration of existing software systems to mobile computing *** investigate the research state-of-the-art on the migration of existing software systems to mobile computing *** aim to analyze the progression and impacts of existing research,highlight challenges and solutions that reflect dimensions of emerging and futuristic *** followed evidence-based software engineering(EBSE)method to conduct a systematic mapping study(SMS)of the existing research that has progressed over more than a decade(25 studies published from 1996–2017).We have derived a taxonomical classification and a holistic mapping of the existing research to investigate its progress,impacts,and potential areas of futuristic research and *** SMS has identified three types of migration namely Static,Dynamic,and State-based Migration of existing software systems to mobile computing *** to mobile computing platforms enables existing software systems to achieve portability,context-sensitivity,and high ***,mobile systems may face some challenges such as resource poverty,data security,and *** emerging and futuristic research aims to support patterns and tool support to automate the migration *** results of this SMS can benefit researchers and practitioners-by highlighting challenges,solutions,and tools,etc.,-to conceptualize the state-of-the-art and futuristic trends that support migration of existing software to mobile computing.

关键词： evidence-based software engineering mapping study software evolution mobile computing

Solution approximations for a mathematical model of relativistic electrons with beta derivative

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 469-485页

作者： ibrahim Yalcinkaya Orkun Tasbozan Ali Kurt Hijaz ahmad Department of Mathematics and Computer Sciences Faculty of ScienceNecmettin Erbakan UniversityKonyaTurkey Department of Mathematics Faculty of Science and LiteratureHatay Mustafa Kemal UniversityHatayTurkey Department of Mathematics Faculty of SciencePamukkale UniversityDenizliTurkey Near East University Operational Research Center in HealthcareTRNC Mersin 10Nicosia99138Turkey Department of Mathematics Faculty of ScienceIslamic University of MadinahMadinahSaudi Arabia

The main aim of this paper is to obtain the exact and semi-analytical solutions of the nonlinear Klein-Fock-Gordon(KFG)equation which is a model of relativistic electrons arising in the laser thermonuclear fusion with beta *** this purpose,both the modified extended tanh-function(mETF)method and the homotopy analysis method(HAM)are *** applying the mETF the chain rule for beta derivative and complex wave transform are used for obtaining the exact *** advantage of this procedure is that discretization or normalization is not *** applying the mETF,the exact solutions are ***,by applying the HAM semi-analytical results for the considered equation are *** HAM?curve gives us a chance to find the suitable value of the for the convergence of the solution ***,comparative graphical representations are given to show the effectiveness,reliability of the *** results show that the m ETF and HAM are reliable and applicable tools for obtaining the solutions of non-linear fractional partial differential equations that involve beta *** study can bring a new perspective for studies on fractional differential *** the other hand,it can be said that scientists can apply the considered methods for different mathematical models arising in physics,chemistry,engineering,social sciences and *** involves fractional *** the results may cause a new insight who studies on relativistic electron modelling.

关键词： Klein-Fock-Gordon(KFG)equation beta derivative semi-analytical solution exact solution