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Thermal Spin Squeezing as a Signature of Thermal Global Entanglement in Heisenberg Models

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Communications in Theoretical Physics 2012年第8期58卷 198-204页

作者： Mojtaba Jafarpour Azita naji Physics Department Shahid Chamran University

We study thermal spin squeezing (TSS) and thermal global entanglement (TGE) in a general Heisenberg spin chain, in the presence of Dzyaloshinskii-Moriya interaction and an external magnetic field. We derive an inequality associating the squeezing parameter and the global concurrence, which establishes (TSS) as a signature of (TGE). The inequality reduces to equality for particular symmetric chains which also associates TSS with bipartite entanglement in such systems. We also check the results by presenting two numerical examples.

关键词： thermal spin squeezing thermafglobal entanglement Heisenberg model global concurrence

Literary placemaking and narrative immersion in extended reality virtual geographic environments

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International Journal of Digital Earth 2022年第1期15卷 853-867页

作者： Michal Rzeszewski Jeneen naji Faculty of Human Geography and Planning Adam Mickiewicz University in PoznanPoznanPoland Department of Media Studies Maynooth UniversityMaynoothIreland

Virtual geographical environments(VGEs)are being used to represent our sense of place through the application of extended-reality or cross-reality(XR)technologies with a focus on technological advancement and *** light of this,we propose that an expanded and interdisciplinary understanding of the concept of immersion is required to facilitate an understanding of spatial data to a broader *** potential of focusing on narrative immersion and literary placemaking in VGEs is discussed to evoke a stronger sense of place and a feeling of presence and belonging in *** paper seeks to highlight the unique affordances and potentialities of XR narrative style GIS digital representations through an interdisciplinary theoretically lead analysis of outputs created by the Building City dashboards project towards the goal of expanding audiences of non-specialist stakeholders in urban planning processes.

关键词： Literary placemaking immersion extended-reality(XR) virtual geographic environments(VGE) urban planning

Comprehensive evaluation and sensitivity analysis of regeneration energy for acid gas removal plant using single and activated-methyl diethanolamine solvents

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1684-1693页

作者： Ammar Ali Abd Samah Zaki naji Ahmed Barifcani Water Resources Engineering College Al-Qasim Green UniversityBabylonIraq Petroleum Engineering Department Kerbala UniversityKerbalaIraq Chemical Engineering Department Curtin University of TechnologyPerthAustralia.

The absorption of acid gas using reactive amines is among the most widely used types of capturing ***,the absorption process requires intensive energy expenditure majorly in the solvent regeneration *** study simultaneously evaluated the regeneration energy of MDEA and PZ/MDEA solvents in terms of heat of absorption,sensible heat,and vaporization *** Hysys version 8.8 simulation tool is applied to model the full acid gas removal plant for the chemical absorption *** new energy balance technique presents around the absorption and desorption columns to bring a new perspective of energy distribution in the capturing of acid gas *** analysis of regeneration energy and its three contributors is performed at several operation parameters such as absorber and stripper pressures,lean amine circulation rate,solvent concentration,reflux ratio,and CO2 and H2 S *** results show that the heat of absorption of PZ/MDEA system is higher than that for MDEA system for the same operating *** sensible heat is the main contributor in the required regeneration energy of MDEA solvent *** simulation results have been validated against data taken from real plant and *** product specifications of our simulation corroborate with real plant data in an excellent approach;additionally,the profile temperature of the absorber and the stripper columns are in good agreement with *** overall results highlight the direction of the effects of each parameter on the heat of absorption,sensible heat,and vaporization heat.

关键词： Heat of absorption Sensible heat Vaporization heat Regeneration energy Acid gases capturing Piperazine Activated-Methyl diethanolamine

Service restoration in distribution networks using combination of two heuristic methods considering load shedding

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Journal of Modern Power Systems and Clean Energy 2015年第4期3卷 556-564页

作者： Meysam GHOLAMI Jamal MOSHTAGH naji GHADERNEJAD Department of Electrical Engineering University of KurdistanKurdistanIran West Regional Electrical Company KermanshahIran

Two heuristic methods are proposed to find an effective and fast solution in modern power distribution *** solving the service restoration problem in distribution networks,switch selection indices based on an analytic approach and a practicable heuristic graph-based method are *** formulation of the problem includes four different objective functions:1)maximizing the total load restored;2)minimizing the number of switching operations;3)maximizing the top priority restored load;4)minimizing load shedding.A suitable evaluation of switch indices is used for all candidate tie switches(TSs)in the network to find the best solution and decrease the number of switching operations.A new graph-based approach is utilized for finding the best sectionalizes switch(SS)and minimizing the voltage *** accuracy and the validity of the approach are tested in two standard electrical distribution *** results of the approach are used for IEEE 69-bus and IEEE 119-bus test case.

关键词： Service restoration Modern distribution networks Smart grid Switch indices Graph-based method

Spatial Distribution and Anthropogenic Assessment of Heavy Metals in the Surface Sediments of Klang River

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湿地科学 2011年第1期9卷 8-18页

作者： Abolfazl naji Ahmad Ismail Department of Biology Faculty of science University Putra Malaysia

The study was conducted to quantify the concentration and distribution of metals (Cd, Zn, Ni, Cu, Pb, and Fe) in the surface sediments and to assess the status of metal contaminations in the Klang River, Malaysia. The concentrations of metals (μg∕g, Fe%, dry weight) were as follows: 0.57-2.19 μg∕g Cd; 31.89-272.33 μg∕g Zn; 5.96-24.47 μg∕g Ni; 10.57-52.87 μg∕g Cu; 24.23-64.11 μg∕g Pb and 1.56%-3.03% Fe. Sequential extraction technique (SET) showed that mean anthropogenic portions of metals were in the order of Zn (60.22%), Cu (56.01%), Cd (45.63%), Ni (42.08%), Pb (33.22%) and Fe (10.26%). The highest concentrations of metals ( p<0.05) were found in the stations located close to industrial parks and highly populated areas. The results of the present study showed that the effectiveness of total organic carbon (TOC) contents in controlling the distribution and enrichment of metals was a more important factor compared to grain size. The study also indicated that the control of metals pollution from direct influx of domestic wastes and insufficiently treated industrial wastes in the Klang River was an important and desirable way to minimize the detrimental effects of metals.

关键词： heavy metals spatial distribution surface sediment anthropogenic assessment

On Modules Satisfying S-Noetherian Spectrum Condition

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Communications in Mathematics and Statistics 2023年第3期11卷 649-662页

作者： MehmetÖzen Osama A.naji Ünsal Tekir Suat Koç Department of Mathematics Sakarya UniversitySakaryaTurkey Department of Mathematics Marmara UniversityIstanbulTurkey

Let R be a commutative ring having nonzero identity and M be a unital *** that S⊆R is a multiplicatively closed subset of ***,M satisﬁes S-Noetherian spectrum condition if for each submodule N of M,there exist s∈S and aﬁnitely generated submodule F⊆N such that sN⊆radM(F),where radM(F)is the prime radical of F in the sense(McCasland and Moore in Commun Algebra 19(5):1327–1341,1991).Besides giving many properties and characterizations of S-Noetherian spectrum condition,we prove an analogous result to Cohen’s theorem for modules satisfying S-Noetherian spectrum ***,we characterize modules having Noetherian spectrum in terms of modules satisfying the S-Noetherian spectrum condition.

关键词： Noetherian modules S-Noetherian modules Noetherian spectrum S-Noetherian spectrum condition

Investigation of the fluid flow in an isolated rotor-stator system with a peripheral opening

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Science China(Physics,Mechanics & Astronomy) 2013年第4期56卷 745-754页

作者： DEBUCHY Roger ABDEL NOUR Fadi naji Hassane BOIS Gérard Laboratoire Génie Civil & géo-Environnement (LGCgE- EA 4515) UArtois/FSA Béthune F-62400 Béthune France Université Lille Nord de France F-59000 Lille France Damascus University Department of Water Engineering Damascus Syria LML-PRES Lille Nord de France Arts et Métiers ParisTech Lille France

This paper deals with an experimental, theoretical and numerical study of a turbulent flow with separated boundary layers between a rotor and a stator. The system is not subjected to any superimposed radial flow. The periphery of the cavity is opened to the atmosphere so that the solid body rotation for infinite discs is not always observed. Emphasis was placed on develop- ment of an asymptotic approach and a step-by-step method to compute the radial distribution of the core swirl ratio and the static pressure on the stator side. The theory also includes the radial and axial velocities in the core region. The numerical simulation has been conducted with the commercial CFD code Fluent 6.1. The k- SST turbulence model is used, with the assumption of 2D-axisymmetric and steady flow. CFD validations have been performed by comparison of the numerical results with the corresponding theoretical results. Numerical and experimental results are in good agreement with analytical solutions.

关键词： rotor-stator cavity analytical solution numerical simulations k- SST turbulence model

Investigating the influence of gamma ray energies and steel fiber on attenuation properties of reactive powder concrete

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Nuclear Science and Techniques 2017年第10期28卷 113-120页

作者： Shatha D.Mohammed Wasan Z.Majeed Nesreen B.naji Nada Mahdi Fawzi Department of Civil College of EngineeringUniversity of BaghdadBaghdadIraq Department of Physics College of ScienceUniversity of BaghdadBaghdadIraq

The effect of gamma ray energies and volume ratio of micro steel fiber(1 and 1.5%) on attenuation properties of reactive powder concrete(70 MPa compressive strength) was investigated. Different characteristics have been considered such as linear attenuation coefficient,mass attenuation coefficient, and half-value *** iodide crystal with a gamma ray spectrometer and collimated beam of gamma ray has been implemented to perform the experimental test. Three sources(Cs-137, Co-60, and Bi-207) with energies of(0.662, 1.17 1.33, 0.569,and 1.063) MeV were adopted in the test. The results obtained indicated that mass attenuation coefficient is proportioned inversely with gamma ray energies and directly with a volume ratio of micro steel fiber. The linear attenuation coefficient and half-value thickness of the tested samples have been calculated and discussed. The obtained results showed that increasing the volume ratio of steel fiber has modified the adequacy of the reactive powder concrete as a shielding element since it increases the density and reduces the half-value thickness.

关键词：活性粉末混凝土衰减特性射线能量钢纤维性能影响线性衰减系数质量衰减系数纤维体积比

Research of the Vortex-induced Vibration and Aerodynamic Countermeasures on a Cable-stayed Bridge with Π-shaped Main Girder Section

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Research of the Vortex-induced Vibration and Aerodynamic Cou...

作者： naji HAMDI najiB AHMED 湖南大学

学位级别：硕士

由于Ⅱ型断面斜拉桥具有施工方便、建设周期短和自重较轻等特点,近年来得到广泛应用。该类桥型主跨通常在200～600m,但由于其主梁为开口截面,具有明显的钝体特性,在风荷载作用下,尾流中易产生周期性旋涡脱落,又因其质量较轻,抗扭刚度较... 详细信息

由于Ⅱ型断面斜拉桥具有施工方便、建设周期短和自重较轻等特点,近年来得到广泛应用。该类桥型主跨通常在200～600m,但由于其主梁为开口截面,具有明显的钝体特性,在风荷载作用下,尾流中易产生周期性旋涡脱落,又因其质量较轻,抗扭刚度较小,气动稳定性较差,以至于该类桥梁在低风速下容易发生涡激振动。虽然涡激振动是一种限幅振动,不会引起结构毁灭性破坏,但其发生风速较低,振幅过大可能引起结构疲劳问题和行人行车安全性及舒适性问题。因此,研究Ⅱ型断面斜拉桥涡激振动特性及气动抑制措施具有较大意义和实际工程价值。本文结合节段模型风洞试验,研究了Ⅱ型主梁断面的静气动力系数、涡激振动特性及气动控制措施,并结合数值模拟对涡激振动及控制机理进行了分析,具体包括如下几方面内容:(1)对在建的潮汕大桥进行节段模型风洞试验,测得原始主梁断面的涡激振动响应,结果表明:Ⅱ型钢-混凝土结合梁断面原设计方案在+3°攻角下,当实桥桥面高度处风速为30.0～50.0m/s时,存在明显的竖向涡激共振现象,最大振幅为0.25m,超过规范允许值,不能满足要求。(2)对潮汕大桥原始断面发生的涡激振动,采取气动控制措施对其进行抑制,并考虑附属设施对涡激振动性能的影响,结果表明:通过采取三道加高后的下稳定板、两侧竖向裙板及增大阻尼比后的组合气动控制措施后,主梁断面的涡激振动性能满足规范要求;采取气动控制措施后的主梁断面在施工状态下的涡激振动性能满足规范要求。增加附属设施后,在风攻角为α=+3°下,成桥状态主梁断面发生了大幅扭转涡振现象,振幅不能满足规范要求,而增大紊流度至Iu=3.0%后,主梁断面成桥状态未观测到明显的涡激振动现象。(3)针对采取气动控制措施的主梁断面进行了测力试验,并基于风洞试验参数,建立主梁断面CFD二维数值模型。将CFD计算所得静气动力系数与风洞试验结果进行比对,说明了数值模拟的准确性;而后计算分析了潮汕大桥Ⅱ型主梁断面静态绕流情况,并对主梁断面涡激振动及制振机理进行了分析,计算结果表明:原设计方案主梁断面上、下表面的压力差是导致涡激振动的关键因素,同时与尾流区卡门涡街形成的周期性压力差共同作用导致主梁原设计方案断面产生较大的竖向涡激力,从而引起主梁断面发生竖向涡激共振现象;设置三道下稳定板可将有效破坏Ⅱ型主梁下侧较大旋涡,Ⅱ型主梁两侧设置竖直裙板改善了其气动流线型程度,设置上中央稳定板可有效阻止主梁上侧较大旋涡的运动。(4)基于潮汕大桥主梁断面参数,设计了两类不同开口宽度的裸梁断面,并通过CFD计算得到了两类不同开口宽度裸梁断面的静气动力系数,计算结果表明:在+3°攻角下,相较于潮汕大桥主梁断面,减小开口宽度至17.5m后,阻力系数减小而升力系数及扭矩系数增大;增大开口宽度至31.5m后,阻力系数及升力系数增大而扭矩系数减小。

关键词：斜拉桥 Π型断面静气动力系数涡激振动气动控制措施风洞试验数值模拟