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Investigation and optimization of solar collector and geothermal pump hybrid system for cogeneration of heat and power with exergy-economic approach

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Clean Energy 2023年第3期7卷 571-581页

作者： Ghassan F.Smaisim Azher M.Abed Ali Shamel Department of Mechanical Engineering Faculty of EngineeringUniversity of KufaKufa54001Iraq Nanotechnology and Advanced Materials Research Unit(NAMRU) Faculty of EngineeringUniversity of KufaKufa54001Iraq Air Conditioning and Refrigeration Techniques Engineering Department Al-Mustaqbal University CollegeBabylon51001Iraq Department of Chemistry Ardebil BranchIslamic Azad UniversityArdebilIran

To use energy systems based on renewable sources,it is very important to consider backup and hybrid sources because renewable energies are not available all the time;therefore,in this system,a geothermal pump is used to preheat the fluid,then the heated fluid is sent to the vacuum tube collector to reach a higher temperature by absorbing solar-thermal energy,and after absorbing solar energy,it goes to the evaporator to produce superheated steam and finally the superheated fluid moves to the steam turbine to produce *** the simulation,thermodynamic analysis along with economic analysis has been *** the base state,the energy efficiency and exergy of cogeneration were 0.566 and 0.156,respectively;the energy efficiency and electrical exergy were better than 0.057 and 0.065;and the overall output and immutable work values were 50 and 671.1 kW,respectively.

关键词： exergoeconomic analysis CHP cycle organic Rankine cycle vacuum tube collector sustainable development

Second-order terminal sliding mode control based on perturbation estimation for nanopositioning stage

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IET Cyber-Systems and Robotics 2020年第4期2卷 161-167页

作者： Ali Al-Ghanimi Jinchuan Zheng Alaa Aldhalemi Jasim Khawwaf Zhihong Man Faculty of Engineering University of KufaAl-Najaf Al-AshrafKufaIraq School of Software and Electrical Engineering Swinburne University of TechnologyAustralia

This study proposes a robust second-order terminal sliding mode control with perturbation estimation(2OTSMCPE)strategy with application to trajectory tracking control of the flexure-based nanopositioning *** proposed controller advantages not only lie on its finite-time convergence but also can provide a high tracking precision with a chattering alleviation which is attend by employing a second-order sliding surface with the switching *** model of the piezo-driven nanopositioning system is presented ***,the sliding variable is designed such as proportional-integral-derivative form to enhance the dynamic response of the control ***,a non-singular terminal sliding function(NTSM)is used to achieve the finite-time convergence of the linear sliding ***,a perturbation estimation technique is integrated with the control structure for online estimation of the system uncertainties,thus the prior knowledge of the bounds of system uncertainties are not needed in the proposed control ***,the theoretical analysis of the 2OTSMCPE with stability proof is investigated ***,the system performance with the proposed controller is experimentally *** results reveal that the 2OTSMCPE has stronger robustness and also has smoother control signals in comparison with both conventional sliding mode control and the NTSM controller.

关键词： estimation perturbation system

On chaotic properties of new semidynamical systems of Lasota type in two spaces

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International Journal of Biomathematics 2018年第5期11卷 201-215页

作者： Habeeb Kareem Abdullah Amal Khalaf Haydar Yaqoob All Hussein Department of Mathematics Faculty of Education for Girls university of kufa Najaf Iraq

The present study is concerned with construct two new semidynamical systems which are generated by two partial differential equations of Lasota type. In addition, this study discusses the asymptotic properties： Strong stability, exponential stability, periodic points, the density of periodic points, transitivity and chaos in two spaces： Lp space and Lp space.

关键词： Initial value problems for linear first-order equations stability periodic solutions chaotic dynamics.

A new approach towards the sustainability of urban-rural integration:The development strategy for central villages in the Abbasiya District of Iraq using GIS techniques

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Regional Sustainability 2023年第1期4卷 28-43页

作者： Ahmed Hussein ALLAWI Haider Mohammed Jawad AL-JAZAERI College of Physical Planning University of KufaNajaf54001Iraq

The development of rural areas usually has a positive impact on the urban-rural integration. This study explores an innovative approach to stimulate rural development by proposing qualified villages as central villages that can provide basic urban services for their residents and residents of neighboring villages. This approach can contribute to overcoming the various problems that rural areas faced at the social, economic, and environmental levels. It seeks to achieve spatial sustainability of rural areas, representing a new approach by integrating urban development methods to revitalize rural villages. The study analyzed 15 villages belonging to Abbasiya District of AL kufa City in the Najaf Governorate of Iraq. Based on the GIS techniques and the analysis of urban service indicators(village population, percentage of urban building materials used in villages, distance between village and health centers, distance between village and main roads, nature of economic activity, distance between village and educational institutions, distance between village and drinking water sources, number of communication towers, and distance between village and urban administrative center), this study proposed that Abu Gharb and Albu Ghraib can served as central villages in Abbasiya District in the future. This study establishes a new rural spatial structure to achieve rural sustainable development, improves the development status of rural areas, and provides a theoretical basis for the government and relevant institutions to use urban service indicators, achieving rural sustainable development and formulating relevant development policies in Abbasiya District.

关键词： Central villages Spatial reorganization Rural sustainable development Urban-rural integration Urban service Abbasiya District Iraq

Extraction of cobalt(Ⅱ) from aqueous solution by N,N'-carbonyl difatty amides

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Chinese Chemical Letters 2011年第4期22卷 469-472页

作者： Emad A.Jaffar Al-Mulla Khalid Waleed S.Al-Janabi Department of Chemistry College of ScienceUniversity of KufaAnNajafIraq Department of Chemistry College of EducationBaghdad UniversityBaghdadIraq

The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this *** this study,solvent extraction of Co（Ⅱ） from aqueous solution using a mixture of N,N＇-carbonyl difatty amides（CDFAs） synthesised from palm oil as the extractant was carried *** effects of various parameters such as acid,contact time,extractant concentration,metal ion concentration and stripping agent and the separation of Co（Ⅱ） from other metal ions such as Fe（Ⅱ）,Ni（Ⅱ）,Zn（Ⅲ） and Cd（Ⅱ） were *** was found that the extraction of Co（Ⅱ） into the organic phase involved the formation of 1：1 ***（Ⅱ） was successfully separated from commonly associated metal ions such as Fe（Ⅱ）,Ni（Ⅱ）,Zn（Ⅲ） and Cd（Ⅱ）.Co（Ⅱ） stripping from the loaded organic phase was studied in aqueous *** results are useful to recover Co（Ⅱ） from aqueous solution utilising（CDFAs） as an extractant.

关键词： N N'-Carbonyl difatty amides Solvent extraction Co(Ⅱ)

Packing unequal circles into a square container based on the narrow action spaces

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Science China(Information Sciences) 2018年第4期61卷 229-231页

作者： Kun HE Mohammed DOSH Yan JIN Shenghao ZOU School of Computer Science and Technology Huazhong University of Science and Technology Shenzhen Research Institute of Huazhong university of Science and Technology Faculty of Education for Girls Kufa University

The single container packing problem consists of allocating a number of items inside one container in order to find the densest packing patterns without *** an important class of optimization problems,packing problems... 详细信息

关键词： PCI Packing unequal circles into a square container based on the narrow action spaces PAS

A study of the operating parameters and barrier thickness of Al_(0.08)In_(0.08)Ga_(0.84)N/Al_xIn_yGa_(1-x-y)N double quantum well laser diodes

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Science China(Technological Sciences) 2011年第1期54卷 47-51页

作者： A.J.GHAZAI S.M.THAHAB H.ABU HASSAN Z.HASSAN Nano-Optoelectronics Research and Technology Laboratory School of PhysicsUniversiti Sains Malaysia Material Engineering Department College of EngineeringUniversity of Kufa

The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using the program, Integrated System Engineering-Technical Computer Aided Design （ISE-TCAD）. Various thicknesses （6, 7, 8, 10, 12 rim） of AlxInyGa1-x-yN barriers with （3 nm） Al0.08In0.08Ga0.84N wells as an active region were studied. The lowest threshold current （lth）, and the highest output power （Pop） were 116 mA and 196 mW respectively, at barriers thickness of 6 nm, Al mole fraction of 10% and In mole fraction of 1%, at an emission wavelength of 359.6 nm.

关键词： AIInGaN quaternary UV laser diode quantum well barrier thickness

Single-Bit Comparator in Quantum-Dot Cellular Automata (QCA) Technology Using Novel QCAXNOR Gates

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Journal of Electronic Science and Technology 2021年第3期19卷 263-273页

作者： Ali Hussien Majeed Mohd Shamian Zainal Esam Alkaldy Danial Md.NorNor Department of Electrical Engineering University of KufaNajaf 54003 Department of Electrical Engineering Technology Universiti Tun Hussein Onn MalaysiaParit Raja 86400

To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology *** scaling scenario is not an option nowadays and other technologies need to be *** quantum-dot cellular automata(QCA)technology is one of the important emerging nanotechnologies that have attracted much researchers’attention in recent *** technology has many interesting features,such as high speed,low power consumption,and small *** features make it an appropriate alternative to the CMOS *** paper suggests three novel structures of XNOR gates in the QCA *** presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new *** proposed structures are used as the main building blocks for a single-bit *** resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the *** comparison results are encouraging to append the proposed structures to the library of QCA gates.

关键词： Nanotechnology quantum-dot cellular automata(QCA) QCA comparator XNOR gate XOR gate

Well-Posedness and Exponential Estimates for the Solutions to Neutral Stochastic Functional Differential Equations with Infinite Delay

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Journal of Systems Science and Information 2020年第5期11卷 434-446页

作者： Hussein K.ASKER Department of Mathematics Faculty of Computer Science and MathematicsKufa UniversityIraq Department of Mathematics College of ScienceSwansea UniversityUK

In this work,neutral stochastic functional differential equations with infinite delay(NSFDEw ID)have been *** using the Euler-Maruyama scheme and a localization argument,the existence and uniqueness of solutions to NSFDEw ID at the state space Cr under the local weak monotone condition,the weak coercivity condition and the global condition on the neutral term have been *** addition,the L2 and exponential estimates of NSFDEw ID have been studied.

关键词： neutral stochastic functional differential equations infinite delay state space C_r Euler-Maruyama scheme