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Clean Energy 2023年第3期7卷 509-518页

作者： Adnan Shariah Emad hasan Physics Department Jordan University of Science and TechnologyPO Box 3030IrbidJordan

Solar concentrators are used in solar photovoltaic systems to lower the cost of producing *** this situation,fewer solar cells can be used,lowering the overall cost of the *** purpose of this article is to design,construct,install and test a stationary(non-tracking)concentrating system in Irbid,*** solar cells are used in the *** concentrator designs(with the same concentration ratio)are experimentally ***-A has a parabolic shape in the lower part but flat reflecting walls,whereas Conc-B has a standard compound parabolic shape in all *** receiving solar cells are arranged in three distinct positions in each *** results reveal that the output power from both concentrators is affected by the placement of the receiving solar cells within the *** has also been found that concentrators with flat reflecting walls perform better than those with parabolic reflecting ***-A’s power collection is~198%greater than that of a non-concentrating *** Conc-B is used,the increase in power is~181%.

关键词： bifacial solar cell non-tracking system parabolic trough concentration PV concentrators

The NF-Number of a Simplicial Complex

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Algebra Colloquium 2022年第4期29卷 643-650页

作者： Takayuki Hibi hasan Mahmood Department of Pure and Applied Mathematics Graduate School of Information Science and Technology Osaka University SuitaOsaka 565-0871Japan Department of Mathematics Government College University LahorePakistan

Let△bea simplicial complex on[n].TheNF-complex of△is the simplicial complexδ_(NF)(△)on[n]for which the facet ideal of△is equal to the Stanley-Reisner ideal ofδ_(NF)(△).Furthermore,for each k=2,3,....,we introduce the kth NF-complexδ_(NF)^(k)(△),which is inductively defined asδ_(NF)(k)(△)=δ_(NF)(δ_(NF)^(k-1)(△))by settingδ_(NF)^(1)(△)=δ_(NF)(△).One canδ_(NF)^(0)(△)=△.The NF-number of△is the smallest integer k>0 for whichδ_(NF)^(k)(△)■△.In the present paper we are especilly interested in the NF-number of a finite graph,which can be regraded as a simplicial complex of dimension *** is shown that the NF-number of the finite graph K_(n)■K_(m)on[n+m],which is the disjoint union of the complete graphs K_(n)on[n]and K_(m)on[m]for n≥2 and m≥2 with(n,m)≠(2,2),is equal to n+m+*** a corollary,we find that the NF-number of the complete bipartite graph K_(n,m)on[n+m]is also equal to n+m+2.

关键词： Stanley-Reisner complex facet ideal simplicial complex vertex cover

A Generalized Accelerated Failure Time Model to Predict Restoration Time from Power Outages

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International Journal of Disaster Risk Science 2023年第6期14卷 995-1010页

作者： Tasnuba Binte Jamal Samiul hasan Department of Civil Environmentaland Construction EngineeringUniversity of Central FloridaOrlandoFL 32816USA

Major disasters such as wildfire, tornado, hurricane, tropical storm, and flooding cause disruptions in infrastructure systems such as power and water supply, wastewater management, telecommunication, and transportation facilities. Disruptions in electricity infrastructure have negative impacts on sectors throughout a region, including education, medical services,financial services, and recreation. In this study, we introduced a novel approach to investigate the factors that can be associated with longer restoration time of power service after a hurricane. Considering restoration time as the dependent variable and using a comprehensive set of county-level data, we estimated a generalized accelerated failure time(GAFT) model that accounts for spatial dependence among observations for time to event data. The model fit improved by 12% after considering the effects of spatial correlation in time to event data. Using the GAFT model and Hurricane Irma's impact on Florida as a case study, we examined:(1) differences in electric power outages and restoration rates among different types of power companies—investor-owned power companies, rural and municipal cooperatives;(2) the relationship between the duration of power outage and power system variables;and(3) the relationship between the duration of power outage and socioeconomic attributes. The findings of this study indicate that counties with a higher percentage of customers served by investor-owned electric companies and lower median household income faced power outage for a longer time. This study identified the key factors to predict restoration time of hurricane-induced power outages, allowing disaster management agencies to adopt strategies required for restoration process.

关键词： Generalized accelerated failure time model Hurricanes Investor-owned power companies Median income Power outage Restoration time

Optical wavelength meter with machine learning enhanced precision

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Photonics Research 2023年第3期11卷 420-430页

作者： GAZI MAHAMUD hasan MEHEDI hasan PENG LIU MOHAMMAD RAD ERIC BERNIER TREVOR JAMES HALL Photonic Technology Laboratory Advanced Research ComplexUniversity of OttawaK1N 6N5 OntarioCanada Huawei Technologies Canada KanataK2K 3J1 OntarioCanada

A photonic implementation of a wavelength meter typically applies an interferometer to measure the frequencydependent phase shift provided by an optical delay *** work shows that the information to be retrieved is encoded by a vector restricted to a circular cone within a 3D Cartesian object *** measured data belong to the image of the object space under a linear orthogonal *** impairments result in broken orthogonal symmetry,but the mapping remains *** circular cone is retained as the object space,which suggests that the conventional conic section fitting for the wavelength meter application is a premature reduction of the object space from R^(3)to R^(2).The inverse map,constructed by a learning algorithm,compensates impairments such as source intensity fluctuation and errors in delay time,coupler transmission,and photoreceiver sensitivity while being robust to *** simple algorithm does not require initial estimates for all parameters except for a broad bracket of the delay;further,weak nonlinearity introduced by uncertain delay can be corrected by a robust golden search *** phase-retrieval process is invariant to source power and its *** demonstrate that,to the extent that the ten parameters of the interferometer model capture all significant impairments,a precision limited only by the level of random noise is *** to measured data collected from a fabricated Si_(3)N_(4)wavelength meter,greater than an order of magnitude improvement in precision compared with the conventional method is achieved.

关键词： delay circular invariant

Efficient Wind Turbine Generation Planning for Decreasing Distribution System Company Payments in Real Applications

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 81-90页

作者： Mohammad hasan Hemmatpour Mohammad Hossein Rezaeian Koochi Electrical Engineering Department Faculty of EngineeringJahrom UniversityJahromIran Department of Electrical Engineering Shahid Bahonar University of KermanKermanIran

Wind energy has posed new challenges in both transmission and distribution systems owing to its uncertain nature. The effect of wind turbines (WTs) on the actual payments charged by upstream networks to distribution system companies (DISCOs) is one challenge. Moreover, when the grid-connected inverters of WT operate in the lead or lag modes, WTs absorb or inject reactive power from the system. This paper proposes an approach to assess the importance of operation modes of WTs to minimize the costs by DISCOs in the presence of system uncertainties. Accordingly, an optimization problem is formulated to minimize the costs to DISCO by determining the optimal locations and sizes of WTs in optimally reconfigured distribution systems. In addition, an improved vector-based swarm optimization (IVBSO) algorithm is proposed because it is highly suitable for vector-based problems. Two distribution systems are used in the simulations to evaluate the proposed algorithm. Firstly, the capabilities of the IVBSO algorithm to determine better solutions over other heuristic algorithms are confirmed using the IEEE 33-bus test system. Secondly, the BijanAbad distribution system (BDS) is used to demonstrate the effectiveness of the proposed optimization problem. Accordingly, the distribution system model, cumulative distribution function of wind speed, and load profile are all extracted from the actual data of the BijanAbad region. Finally, the optimization problem is applied to BDS in both the lead and lag modes of WTs. Results indicate that the total costs of DISCO are lower when WTs operate in the lag mode than in the lead mode.

关键词： Distribution system companies(DISCOs) improved vector-based swarm optimization(IVBSO) reconfiguration wind turbine operation mode

“蒙医秘诀方海”记载中自因疮疡类疾病的命名研究

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中国蒙医药（蒙） 2024年第1期19卷 13-19页

作者：白领兄包哈申不详

Crack Propagation in Pipelines Under Extreme Conditions of Near-Neutral PH SCC

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Computers, Materials & Continua 2022年第12期73卷 5315-5329页

作者： Abdullah Alsit Mohammad Alkhedher hasan Hamdan Mechanical Engineering Department College of EngineeringAbu Dhabi UniversityAbu Dhabi59911United Arab Emirates

Stress Corrosion Cracking(SCC)process through which cracks occur in a variety of susceptible materials is a result of a combination of residual or applied stresses and *** oil and gas field,buried pipeline steels are made of low-alloy steels with a ferritic-pearlitic structure,such as *** dilute solutions,these materials are prone to SCC *** Near-neutral simulated soil solution(NS4)solution is established to imitate SCC conditions and subsequently became the industry requirement for crack growth experiments in the majority of *** strainassisted active crack pathways are considered while modelling SCC growth as an oxide film rupture and anodic dissolution ***’s been hypothesized that increasing the strain concentration can help with dissolution at the filmfree crack *** research focuses on estimating the SCC crack growth rate under various environmental conditions in oil and gas pipelines using finite element *** simulation is carried out using the J-integral theory in the COMSOL Multiphysics *** are performed to model the crack growth rate(CGR)using slip anodic dissolution(film rupture)*** plastic strain gradient is required to compute the SCC CGR(da/dt).Because the plastic strain located at crack tip increases proportionally to the crack length as it propagates,the CGR increases as the stress intensity factor(SIF)*** crack growth rates increase when constant loads are applied and as the temperature rises,and elevating the cathodic potential has a minimal influence on the propagation rate of cracks but raises the material yield strength and imparts brittle behavior to it.

关键词： Stress corrosion cracking SCC oxide film rupture and anodic dissolution crack growth rate CGR J-integral stress intensity factor SIF

Mitochondrial complex Ⅰ as a therapeutic target for Alzheimer’s disease

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Acta Pharmaceutica Sinica B 2022年第2期12卷 483-495页

作者： Eugenia Trushina Sergey Trushin Md Fayad hasan Department of Neurology Mayo ClinicRochesterMN 55905USA Department of Molecular Pharmacology and Experimental Therapeutics Mayo ClinicRochesterMN 55905USA

Alzheimer’s disease(AD),the most prominent form of dementia in the elderly,has no *** focused on the reduction of amyloid beta or hyperphosphorylated Tau protein have largely failed in clinical *** therapeutic targets and strategies are urgently *** data suggest that in response to environmental stress,mitochondria initiate an integrated stress response(ISR)shown to be beneficial for healthy aging and ***,we review data that implicate mitochondrial electron transport complexes involved in oxidative phosphorylation as a hub for small molecule-targeted therapeutics that could induce beneficial mitochondrial ***,partial inhibition of mitochondrial complex I has been exploited as a novel strategy for multiple human conditions,including AD,with several small molecules being tested in clinical *** discuss current understanding of the molecular mechanisms involved in this counterintuitive *** this strategy has also been shown to enhance health and life span,the development of safe and efficacious complex Ⅰ inhibitors could promote healthy aging,delaying the onset of age-related neurodegenerative diseases.

关键词： Mitochondria Mitochondria signaling ComplexⅠinhibitors Alzheimer’s disease Integrated stress response Neuroprotection Mitochondria targeted therapeutics Healthy aging

Practical autoencoder based anomaly detection by using vector reconstruction error

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Cybersecurity 2023年第2期6卷 1-13页

作者： hasan Torabi Seyedeh Leili Mirtaheri Sergio Greco Department of Electrical and Computer Engineering Faculty of EngineeringKharazmi UniversityTehranIran Department of Informatics ModelingElectronics and System EngineeringUniversity of CalabriaArcavacataItaly.

Nowadays,cloud computing provides easy access to a set of variable and configurable computing resources based on user demand through the *** computing services are available through common internet protocols and network standards.n addition to the unique benefits of cloud computing,insecure communication and attacks on cloud networks cannot be *** are several techniques for dealing with network *** this end,network anomaly detection systems are widely used as an effective countermeasure against network *** anomaly-based approach generally learns normal traffic patterns in various ways and identifies patterns of *** anomaly detection systems have gained much attention in intelligently monitoring network traffic using machine learning *** paper presents an efficient model based on autoencoders for anomaly detection in cloud computing *** autoencoder learns a basic representation of the normal data and its reconstruction with minimum ***,the reconstruction error is used as an anomaly or classification *** addition,to detecting anomaly data from normal data,the classification of anomaly types has also been *** have proposed a new approach by examining an autoencoder's anomaly detection method based on data reconstruction *** the existing autoencoder-based anomaly detection techniques that consider the reconstruction error of all input features as a single value,we assume that the reconstruction error is a *** enables our model to use the reconstruction error of every input feature as an anomaly or classification *** further propose a multi-class classification structure to classify the *** use the CIDDS-001 dataset as a commonly accepted dataset in the *** evaluations show that the performance of the proposed method has improved considerably compared to the existing ones in terms of accuracy,recall,false-positive rate,and F1-score

关键词： Cloud Practical Anomaly detection Autoencoder Reconstruction error Machine learning

Nickel-titanium shape memory alloys made by selective laser melting:a review on process optimisation

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Advances in Manufacturing 2022年第1期10卷 24-58页

作者： Omar Ahmed Mohamed Syed hasan Masood Wei Xu School of Engineering Deakin UniversityGeelongVIC 3216Australia Department of Mechanical Engineering The Higher Institute of Engineering TechnologyBani WaledLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia

Selective laser melting(SLM)is a mainstream powder-bed fusion additive manufacturing(AM)process that creates a three-dimensional(3D)object using a high power laser to fuse fine particles of various metallic powders such as copper,tool steel,cobalt chrome,titanium,tungsten,aluminium and stainless *** the past decade,SLM has received significant attention due to its capability in producing dense parts with superior mechanical *** a premier shape memory alloy,the nickel-titanium(NiTi)shape memory alloy is attractive for a variety of biomedical applications due to its superior mechanical properties,superelasticity,corrosion resistance and *** paper presents a comprehensive review of the recent progress in NiTi alloys produced by the SLM process,with a particular focus on the relationship between processing parameters,resultant microstructures and *** research gaps,challenges and suggestions for future research are also addressed.

关键词： Additive manufacturing(AM) Selective laser melting(SLM) Microstructure NiTi alloy Mechanical properties