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Embedding-based Detection and Extraction of Research Topics from Academic Documents Using Deep Clustering

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Journal of Data and Information Science 2021年第3期6卷 99-122页

作者： Sahand Vahidnia Alireza abbasi Hussein A.Abbass University of New South Wales Canberra2612ACTAustralia

Purpose:Detection of research fields or topics and understanding the dynamics help the scientific community in their decisions regarding the establishment of scientific *** also helps in having a better collaboration with governments and *** study aims to investigate the development of research fields over time,translating it into a topic detection ***/methodology/approach:To achieve the objectives,we propose a modified deep clustering method to detect research trends from the abstracts and titles of academic *** embedding approaches are utilized to transform documents into vector-based *** proposed method is evaluated by comparing it with a combination of different embedding and clustering approaches and the classical topic modeling algorithms(***)against a benchmark dataset.A case study is also conducted exploring the evolution of Artificial Intelligence(AI)detecting the research topics or sub-fields in related AI ***:Evaluating the performance of the proposed method using clustering performance indicators reflects that our proposed method outperforms similar approaches against the benchmark *** the proposed method,we also show how the topics have evolved in the period of the recent 30 years,taking advantage of a keyword extraction method for cluster tagging and labeling,demonstrating the context of the *** limitations:We noticed that it is not possible to generalize one solution for all downstream ***,it is required to fine-tune or optimize the solutions for each task and even *** addition,interpretation of cluster labels can be subjective and vary based on the readers’*** is also very difficult to evaluate the labeling techniques,rendering the explanation of the clusters further *** implications:As demonstrated in the case study,we show that in a real-world example,how the proposed method would enable the researchers and

关键词： Dynamics of science Science mapping Document clustering Artificial intelligence Deep learning

Intelligent non-linear modelling of an industrial winding process using recurrent local linear neuro-fuzzy networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第6期13卷 403-412页

作者： Hasan abbasi NOZARI Hamed DEHGHAN BANADAKI Mohammad MOKHTARE Somayeh HEKMATI VAHED Department of Mechatronics Faculty of EngineeringIslamic Azad UniversityScience and Research BranchTehranIran

This study deals with the neuro-fuzzy (NF) modelling of a real industrial winding process in which the acquired NF model can be exploited to improve control performance and achieve a robust fault-tolerant system. A new simulator model is proposed for a winding process using non-linear identification based on a recurrent local linear neuro-fuzzy (RLLNF) network trained by local linear model tree (LOLIMOT), which is an incremental tree-based learning algorithm. The proposed NF models are compared with other known intelligent identifiers, namely multilayer perceptron (MLP) and radial basis function (RBF). Comparison of our proposed non-linear models and associated models obtained through the least square error (LSE) technique (the optimal modelling method for linear systems) confirms that the winding process is a non-linear system. Experimental results show the effectiveness of our proposed NF modelling approach.

关键词： Non-linear system identification Recurrent local linear neuro-fuzzy (RLLNF) network Local linear model tree(LOLIMOT) Neural network (NN) Industrial winding process

Cattaneo-Christov heat flux model for third-grade fluid flow towards exponentially stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2016年第6期37卷 761-768页

作者： S.A.SHEHZAD F.M.abbasi T.HAYAT B.AHMAD Department of Mathematics Comsats Institute of Information TechnologySahiwal 57000Pakistan Department of Mathematics Comsats Institute of Information TechnologyIslamabad 44000Pakistan Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan NAAM Research Group Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia

The Cattaneo-Christov heat flux in the two-dimensional （2D） flow of a third- grade fluid towards an exponentially stretching sheet is investigated. The energy equation is considered through thermal relaxation. Similarity transformations are accounted to obtain the ordinary differential systems. The converted non-dimensional equations are solved for the series solutions. The convergence analysis of the computed solutions is reported. The graphical results of the velocity and temperature profiles are plotted and elaborated in detail. The results show that the thermal relaxation enhances the temper- ature gradient while reduces the temperature profile.

关键词： steady flow third-grade fluid Cattaneo-Christov heat flux exponentiallystretching sheet

Comparison of Different Dosage of Dexamethasone as Pre-medication in NSCLC Patients with First Line Docetaxel-Platinum-Based Chemotherapy

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Comparison of Different Dosage of Dexamethasone as Pre-medic...

作者： Faisal Sarwar abbasi 大连医科大学

学位级别：硕士

背景:随着肿瘤患病率的不断增加以及肿瘤治疗伴随的强烈不良反应,如何能使肿瘤治疗变得更有效且更安全就变得非常重要。本研究的目的在于对比作为以多西他赛为基础化疗的标准剂量地塞米松及改良低剂量地塞米松预处理,研究改良后的低剂... 详细信息

背景:随着肿瘤患病率的不断增加以及肿瘤治疗伴随的强烈不良反应,如何能使肿瘤治疗变得更有效且更安全就变得非常重要。本研究的目的在于对比作为以多西他赛为基础化疗的标准剂量地塞米松及改良低剂量地塞米松预处理,研究改良后的低剂量地塞米松是否具有与标准剂量地塞米松一样的疗效。方法:本研究选取了 2014年6月至2016年6月就诊大连医科大学附属第一医院肿瘤科的38名非小细胞肺癌患者,将患者分为两组,一组接受标准剂量地塞米松预处理:地塞米松4mg,一天两次口服,连用三天。第二组接受改良后的地塞米松预处理:前一天口服地塞米松7.5mg,次日给予5或10mg地塞米松配伍100ml生理盐水静脉点滴。结果:研究结果表明,地塞米松预处理剂量变化与肿瘤反应、骨髓抑制(血小板减少、中性粒细胞减少)和消化道毒性显著相关。t检验分析结果显示,骨髓抑制(尤其血小板减少症)的发生率在第一组明显增加,此外,无进展生存期的中位平均值为4.26±0.47个月(*P<0.05),危险比为0.87。这表明,给予改良计量地塞米松预处理的患者预后更好。结论:本研究表明对于非小细胞肺癌患者进行以多西他赛为基础的化疗我们认为改良后的低剂量地塞米松预处理更为优选,因为其安全性高且不良反应少。但是,如何确保肿瘤患者的健康以及减少治疗毒性仍然需要更多的研究和学习。

关键词：地塞米松多西他赛非小细胞肺癌术前用药

Surface-Renewable AgNPs/CNT/rGO Nanocomposites as Bifunctional Impedimetric Sensors

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Nano-Micro Letters 2017年第1期9卷 65-75页

作者： Azadeh Azadbakht Amir Reza abbasi Zohreh Derikvand Ziba Karimi Mahmoud Roushani Department of Chemistry Faculty of Science Khorramabad Branch Islamic Azad University Department of Chemistry Ilam University

In this study, glassy carbon electrode modified by silver nanoparticles/carbon nanotube/reduced graphene oxide(AgNPs/CNT/rGO) composite has been utilized as a platform to immobilize cis-dioxomolybdenum(VI)–salicylaldehydehistidine(MoO_2/Sal-His). The modified electrode shows two reversible redox couples for MoO_2/Sal-His. Electrocatalytic oxidation of cysteine(CySH) and electrocatalytic reduction of iodate on the surface of the modified electrode were investigated with cyclic voltammetry and electrochemical impedance spectroscopy methods. The presence of MoO_2/SalHis on AgNPs/CNT/rGO shifted the catalytic current of iodate reduction to a more positive potential and the catalytic current of cysteine oxidation to a more negative potential. The change of interfacial charge transfer resistance(R_(ct))recorded by the modified electrode was monitored for sensitive quantitative detection of CySH and iodate. Moreover, the sensor has a good stability, and it can be renewed easily and repeatedly through a mechanical or electrochemical process.

关键词： Silver nanoparticle rGO MoO2/Sal-His Cysteine Iodate

Materials flow and phase transformation in friction stir welding of Al 6013/Mg

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Transactions of Nonferrous Metals Society of China 2013年第5期23卷 1253-1261页

作者： Pooya POURAHMAD Mehrdad abbasi Department of Materials Science and Engineering Islamic Azad University

Material flow and phase transformation were studied at the interface of dissimilar joint between Al 6013 and Mg, produced by stir friction welding （FSW） experiments. Defect-free weld was obtained when aluminum and magnesium were placed in the advancing side and retreating side respectively and the tool was placed 1 mm off the weld centerline into the aluminum side. In order to understand the material flow during FSW, steel shots were implanted as indexes into the welding path. After welding, using X-ray images, secondary positions of the steel shots were evaluated. It was revealed that steel shots implanted in advancing side were penetrated from the advancing side into the retreating side, whereas the shots implanted in the retreating side remained in the retreating side, without penetrating into the advancing side. The welded specimens were also heat treated. The effects of heat treatment on the mechanical properties of the welds and the formation of new intermetallic layers were investigated. Two intermetallic compounds, Al3Mg2 and Al12Mg17, were formed sequentially at Al6013/Mg interface.

关键词： dissimilar welding friction stir welding interface material flow intermetallic compounds mechanical properties aluminum 6013 magnesium

Damage mechanism at different transpassive potentials of solution-annealed316 and 3161 stainless steels

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 45-51页

作者： K.Morshed Behbahani M.Pakshir Z.abbasi P.Najafisayar Department of Materials Science and Engineering School of EngineeringShiraz University

Electrochemical impedance spectroscopy （EIS）, anodic polarization and scanning electron microscopy techniques were used to investigate the damage mechanism in the transpassive potential region of AISI 316 and AISI 316L solution-annealed stainless steels （SS） with different degrees of sensitization. Depending on the DC potential applied during EIS tests, the AC responses in the transpassive region included three different regions：the first one associated with anodic dissolution of the passive layer, the second one contributed to the disso-lution at the area near grain boundaries, and the last one attributed to pitting corrosion. In addition, the fitting results to experimental data showed that as the DC bias during the EIS test increases the charge transfer resistance （Rct） decreases. Moreover, the Rct values decreased as the sensitization temperature increases but the AISI 316L SS samples exhibited a higher resistance to intergranular corrosion than 316 SS samples.

关键词： stainless steel annealing intergranular corrosion damage mechanisms

CFD simulations of a semi-transverse ventilation system in a long tunnel

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Underground Space 2023年第4期11卷 153-170页

作者： Alireza Dastan Mohammad Rahiminejad Mozhgan Sabz Meisam abbasi Ali Mokhtari Sasan Sadrizadeh Omid Abouali Department of Mechanical Engineering Faculty of EngineeringUniversity of IsfahanIsfahan 81746-73441Iran School of Mechanical Engineering Shiraz UniversityShiraz 71936-16548Iran Department of Mechanical Engineering University of AlbertaEdmonton T6G 2R3Canada Department of Civil and Architectural Engineering KTH UniversityStockholm 10044Sweden

In the present work,a semi-transverse ventilation system in a long tunnel with a length of 4.9 km,as a complex case study,is numer-ically studied by performing a set of three-dimensional steady incompressible computational fluid dynamics(CFD)*** ven-tilation system consisted of a ceiling duct connected to two axial fans at the ending portals,and a series of jet fans in the main tunnel for supporting airflow in the desired *** focus on what can and cannot be achieved in commissioning tests,the ventilation system’s performance in various scenarios is numerically evaluated with two different tunnel states;empty tunnel and complete traffic congestion with 1176 stationary vehicles–which is almost impossible to evaluate during a commissioning *** considering two hypothetical loca-tions for the extraction zone from the main tunnel(in a distance of 450 and 1000 m from one portal),it is shown that the required number of jet fans in a traffic condition drops from 57 for the first extraction location to 43(25%decrease)when the ventilation system extracts from the second *** show that if only the close axial fan to the extraction zone is activated,the required number of jet fans reduces by 56%and 72%for the first and second extraction locations,*** finding can provide a cheaper and easier controlling scenario for emergency ventilation.

关键词： CFD Semi-transverse ventilation Tunnel Ceiling duct Traffic

The Impact of Parental Migration on Middle School Student’s Non-Cognitive Abilities in China Evidence-Based on China Education Panel Survey(CEPS)

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The Impact of Parental Migration on Middle School Student’s...

作者： Babar Nawaz abbasi 陕西师范大学

学位级别：硕士

在中国,大量农村人口外出务工极大地促进了经济的快速增长。当前外出务工人员数量将近1亿。农村人口外出不仅可以通过其劳动力为自己带来实质性的收益,而且会给他们的家庭和他们所在的社区带来强大的影响和变革。这些农村外出人口对家... 详细信息

在中国,大量农村人口外出务工极大地促进了经济的快速增长。当前外出务工人员数量将近1亿。农村人口外出不仅可以通过其劳动力为自己带来实质性的收益,而且会给他们的家庭和他们所在的社区带来强大的影响和变革。这些农村外出人口对家庭结构的影响,特别是对他们孩子所产生的影响非常值得研究。例如,许多案例表明,农村父母搬到城市寻求更高的收入,因而常会将他们的孩子留在家里。父母陪伴的缺乏是影响儿童非认知能力的众多因素之一,它会影响孩子的人格特征或思维模式、感情以及行为模式。儿童发展研究表明,儿童非认知能力的发展水平与他们将来的就业率、受教育水平和自我效能感之间有很强的相关性。更重要的是,对非认知能力的发展进行干预可以改进学生的表现,减少其不当的行为问题。因此,儿童非认知能力的发展关系到中国未来人力资源质量的提高、经济的高质量发展以及社会秩序的稳定。因此,在中国,父母外出是否对留守儿童的非认知能力产生不利影响有待进一步研究。为此,本研究探讨了中国父母外出对中学生非认知能力的影响。本研究通过使用中国教育追踪调查(CEPS)的数据,探索了父母外出对初中学生非认知能力的影响。CEPS是一项大规模、具有全国代表性的纵向调查,从2013/2014年开始,调查以基线队列——7年级农村学生(31个省、自治区、直辖市(不含港澳台地区))28个县级单位的112所学校为调查对象,共调查了 438个班,19487名学生。由中国人民大学国家调查研究中心(NSRC)开展的2014-2015学年调查9年级学生人数为10750。然而,考虑到这项研究的重点是留守儿童,它只关注在基线和末期的农村学生,故本研究采用以下方法:第一,利用描述性统计分析研究变量的统计特征获得变量的基本信息,突出变量之间的潜在关系。第二,采用双重差分模型(DID)来探查父母外出的不同情况对中学生在基期和末期之间的非认知能力的影响,从而了解父母外出对这两个时期是否有影响。第三,本研究采用了平衡测试和共同支持假说测试,因为对倾向得分匹配模型(PSM)的估计需要此类测试。第四,通过使用倾向得分匹配模型合并基线数据和追踪数据,研究了父母外出对中学生非认知能力的影响。最终,本研究进行了父母外出对中学生非认知能力影响的异质性分析(HEA)。双重差分模型(DID)结果显示,在评估父母外出所有不同情况对留守儿童基期和末期非认知能力的影响时,发现所有不同的父母外出情况均不会影响留守儿童的非认知能力。此外,倾向性分数匹配(PSM)的结果表明,父母在家的子女比父母一方外出或双方都外出的子女更有可能获得更高的非认知能力。由于父母外出的子女可能具有较低的非认知能力,这意味着父母一方或双方外出的子女与父母双方都在家的子女的非认知能力存在差异。此外,只有父亲或父母双方外出对子女的非认知能力有负面影响,但母亲一个人外出对子女的非认知能力有积极影响。这表明父母与孩子同住与将孩子留给亲戚、祖父母或其他人相比,对孩子非认知能力的发展会产生更好的影响。此外,异质性分析(HEA)表明,在父母外出的所有情况中,父母外出对子女非认知能力的影响是不同的,非认知能力水平较高的儿童与非认知能力水平低的儿童相比,受父母外出的负面影响较小。此外,从性别角度考虑,在父母外出的所有情况中,那些只有母亲外出的男孩所受的负面影响的要小于只有母亲外出对女孩所带来的影响。因此,父母外出对留守儿童非认知能力的影响存在性别差异。此外,就独生子女而言,最重要的是父母外出的情况,只有父亲或父母双方都外出的独生子女比只有母亲外出的独生子女更容易受到父母外出所带来的负面影响。此外,在所有父母外出的情况中,与只有父亲外出且有非良性朋友的子女相比,父母外出对只有母亲外出且至少有一个非良性朋友的子女所带来的负面影响小。因此,父母外出对留守儿童的非认知能力的影响是敏感的。综上,父母外出对子女非认知能力的影响在性别、是否是独生子女、是否有非良性朋友等方面存在异质性。本研究根据调查结果提出了一些政策建议。首先,对于基线阶段,政府已经采取了控制措施或政策以减少父母外出对子女非认知能力的影响,但在评估期研究发现,父母外出的所有情况在基期和末期之间对留守儿童的非认知能力没有影响。因此,政府应重新制定一套新的计划以尽可能减少父母双方外出对子女非认知能力的影响。其次,关于父母外出后子女在非认知能力方面的问题,政府应鼓励父母外出时带上子女,改善他们的生活环境。例如,通过提供学校、水电、道路、安全等公共服务,以及为经营小型、中型和大型企业提供其他政策性激励措施,以消除父母外出所带来的负面影响。因此,政府必须为创造和改善外出父母所处的环境奠定基础。通过提供工作、增加收入来源和宜居的环境,可以在降低外出率的同时,增加当地的收入并促进发展。再次,由于父母外出对子女非认知能力的影响在性别、是否为独生子女、子女是否有非良

关键词：父母外出非认知能力人力资本发展中国