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Chinese Chemical Letters 2009年第10期20卷 1153-1156页

作者： Khalil Faghihi Polymer Chemistry Research Laboratory Department of ChemistryFaculty of ScienceIslamic Azad UniversityArak BranchArakIran

Six new optically active poly（amide-imide）s （5a-f） were synthesized through the direct polycondensation reaction of N,N′-（4,4′- diphthaloyl）-bis-L-leucine （3） with six hydantoin derivatives （4a-f）. Tripbenyl phosphite （TPP）/pyridine in the presence of calcium chloride （CaCl2） and N-methyl-2-pyrrolidone （NMP） were successfully applied for direct polycondensation. The polycondensation reactions produce a series of new poly（amide-imide）s （5a-f） in high yields, and inherent viscosity between 0.42 and 0,55 dL/g. The resulting poly（amide-imide）s （5a-f） were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis （TGA and DTG）, solubility test and FT-IR spectroscopy.

关键词： High performance polymers Poly(amide-imide)s Direct polycondensation Hydantoin derivatives

Assessment of strength development in stabilized soil with GBR PLUS and silica sand

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第4期4卷 412-421页

作者： Seyed Esmaeil Mousavi Aliakbar Karamvand Department of Civil Engineering College of Engineering Islamic Azad University Zanjan Branch Zanjan Iran College of Civil Engineering Islamic Azad University Tehran Central Branch Tehran Iran

This paper investigates the potential use of a nano polymer stabilizer, namely CBR PLUS for stabilization of soft clay and formulation of an optimal mix design of stabilized soil with CBR PLUS and silica sand. The highway settlements induced by the soft clay are prob- lematic due to serious damages in the form of cracks and deformation. With respect to this, soil compaction and stabilization is regarded as a viable method to treat shallow soft clayey ground for supporting highway embankment. The objectives of this paper are： i） to stabilize the compacted soil with CBR PLUS and silica sand in the laboratory; and ii） to evaluate the permeability, strength and California bearing ratio （CBR） of the untreated and stabilized soil specimens. The suitability of stabilized soil was examined on the basis of standard Proctor compaction, CBR, unconfined compression, direct shear, and falling head perme- ability tests. Furthermore, the chemical composition of the materials was determined using X-ray Fluorescence （XRF） test. It was found that the optimal mix design of the sta- bilized soil is 90% clay, I% CBR PLUS, 9% silica sand. It is further revealed that, stabilization increases the CBR and unconfined compressive strength of the combinations by almost 6- fold and 1.8-fold respectively. In summary, a notable discovery is that the optimum mix design can be sustainably applied to stabilize the shallow clay without failure.

关键词： CBR PLUS Clay Silica sand Permeability Strength

Multi-trial Vector-based Whale Optimization Algorithm

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Journal of Bionic Engineering 2024年第3期21卷 1465-1495页

作者： Mohammad H.Nadimi-Shahraki Hajar Farhanginasab Shokooh Taghian Ali Safaa Sadiq Seyedali Mirjalili Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad***Iran Department of Computer Science Nottingham Trent UniversityNottinghamNG118NSUK Centre for Artificial Intelligence Research and Optimisation Torrens UniversityBrisbane4006Australia

The Whale Optimization Algorithm(WOA)is a swarm intelligence metaheuristic inspired by the bubble-net hunting tactic of humpback *** spite of its popularity due to simplicity,ease of implementation,and a limited number of parameters,WOA’s search strategy can adversely affect the convergence and equilibrium between exploration and exploitation in complex *** address this limitation,we propose a new algorithm called Multi-trial Vector-based Whale Optimization Algorithm(MTV-WOA)that incorporates a Balancing Strategy-based Trial-vector Producer(BS_TVP),a Local Strategy-based Trial-vector Producer(LS_TVP),and a Global Strategy-based Trial-vector Producer(GS_TVP)to address real-world optimization problems of varied degrees of ***-WOA has the potential to enhance exploitation and exploration,reduce the probability of being stranded in local optima,and preserve the equilibrium between exploration and *** the purpose of evaluating the proposed algorithm's performance,it is compared to eight metaheuristic algorithms utilizing CEC 2018 test ***,MTV-WOA is compared with well-stablished,recent,and WOA variant *** experimental results demonstrate that MTV-WOA surpasses comparative algorithms in terms of the accuracy of the solutions and convergence ***,we conducted the Friedman test to assess the gained results statistically and observed that MTV-WOA significantly outperforms comparative ***,we solved five engineering design problems to demonstrate the practicality of *** results indicate that the proposed MTV-WOA can efficiently address the complexities of engineering challenges and provide superior solutions that are superior to those of other algorithms.

关键词： Swarm intelligence algorithms Metaheuristic algorithms Optimization Engineering design problems Whale optimization algorithm

Mathematical method for air electrostatic discharge circuits calculation

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High Voltage 2018年第3期3卷 226-231页

作者： Liu Xinggang Wei Ming Hu Xiaofeng Institute of Electrostatic and Electromagnetic Protection Shijiazhuang Branch of Army Engineering UniversityShijiazhuangPeople's Republic of China

Here,a new analytical method,state matrix transform method,is proposed for calculating the descriptions of current waveforms generated by commercial electrostatic discharge(ESD)*** method can be used to analyse and design lumped parameter ESD circuits.A relatively simple eight elements ESD circuit model is established and used to predict the current waveform of human-metal ESD *** calibrate the ESD simulator,a mathematical expression of four exponentials curve for ESD current waveform is *** careful theoretical study of ESD current waveform calculation makes an innovative contribution to ESD generator circuit simulation and design,and it provides a new mathematical description for ESD sensitivity test.

关键词： electrostatic calculation Mathematical

Customer Activity Sequence Classification for Debt Prevention in Social Security

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Journal of Computer Science & Technology 2009年第6期24卷 1000-1009页

作者：张淮风 Yanchang Zhao 操龙兵张成奇 Hans Bohlscheid Payment Reviews branch Business Integrity Division Centrelink Canberra Australia Centre for Quantum Computation and Intelligent Systems (QCIS) University of Technology Sydney Australia

From a data mining perspective, sequence classification is to build a classifier using frequent sequential patterns. However, mining for a complete set of sequential patterns on a large dataset can be extremely time-consuming and the large number of patterns discovered also makes the pattern selection and classifier building very time-consuming. The fact is that, in sequence classification, it is much more important to discover discriminative patterns than a complete pattern set. In this paper, we propose a novel hierarchical algorithm to build sequential classifiers using discriminative sequential patterns. Firstly, we mine for the sequential patterns which axe the most strongly correlated to each target class. In this step, an aggressive strategy is employed to select a small set of sequential patterns. Secondly, pattern pruning and serial coverage test are done on the mined patterns. The patterns that pass the serial test are used to build the sub-classifier at the first level of the final classifier. And thirdly, the training samples that cannot be covered are fed back to the sequential pattern mining stage with updated parameters. This process continues until predefined interestingness measure thresholds are reached, or all samples axe covered. The patterns generated in each loop form the sub-classifier at each level of the final classifier. Within this framework, the searching space can be reduced dramatically while a good classification performance is achieved. The proposed algorithm is tested in a real-world business application for debt prevention in social security area. The novel sequence classification algorithm shows the effectiveness and efficiency for predicting debt occurrences based on customer activity sequence data.

关键词： sequential pattern mining sequence classification coverage test interestingness measure

In vitro differentiation of human umbilical cord Wharton's jelly mesenchymal stromal cells to insulin producing clusters

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World Journal of Clinical Cases 2015年第7期3卷 640-649页

作者： Seideh Masoomeh Nekoei Negar Azarpira Ladan Sadeghi Sulmaz Kamalifar Transplant Research Center Shiraz University of Medical Science Islamic Azad University Arsanjan Branch

AIM: To investigate the differentiation of human Wharton's jelly derived mesenchymal stromal cells(WJMSCs) to insulin producing clusters(IPC) this study was conducted. METHODS: The umbilical cords samples were collected from full term caesarian section mothers and the WJ-MSCS were cultured from tissue explants in High glucose-Dulbecco's Modified Eagle Medium(H-DMEM); H-DMEM supplemented with 10% fetal bovine serum(FBS) and antibiotics. The expression of CD90, CD44, CD105, CD34 and CD133 as well as osteogenic and adipogenic differentiation of cells in appropriate medium were also evaluated. The cells were differentiated toward IPC with changing the culture medium and adding the small molecules such as nicotinic acid, epidermal growth factor, and exendin-4 during 3 wk period. The gene expression of PDX1, NGN3, Glut2, insulin was monitored by reveres transcription polymerase chain reaction method. The differentiated clusters were stained with Dithizone(DTZ) which confirms the presence of insulin granules. The insulin challenge test(low and high glucose concentration in Krebs-Ringer HEPES buffer) was also used to evaluate the functional properties of differentiated ***: WJ-MSCS were positive for mesenchymal surface markers(CD90, CD44, CD105), and negative for CD34 and CD133. The accumulation of lipid vacuoles and deposition of calcium mineral in cells were considered as adipogenic and osteogenic potential of WJ-MSCS. The cells also expressed the transcriptional factors such as Nanog and OCT4. During this three step differentiation, the WJ-MSCS morphology was gradually changed from spindle shaped cells in to epithelioid cells and eventually to three dimensional clusters. The clusters expressed PDX1, NGN3, Glut2, and insulin. The cells became bright red color when stained with DTZ and the insulin secretion was also confirmed. In glucose challenge test a significant increase in insulin secretion from 0.91 ± 0.04 μIu/mL(2.8 mmol/L glucose) to to 8.34 ± 0.45 μIu

关键词： Mesenchymal stromal cells Umbilical cord Beta cell Islet

A Novel Image Categorization Strategy Based on Salp Swarm Algorithm to Enhance Efficiency of MRI Images

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Computer Modeling in Engineering & Sciences 2019年第4期119卷 185-205页

作者： Mohammad Behrouzian Nejad Mohammad Ebrahim Shiri Ahmadabadi Department of Computer Engineering Borujerd BranchIslamic Azad UniversityBorujerdIran Department of Mathematics and Computer Science AmirkabirUniversityTehranIran

The main target of this paper is presentation of an efficient method for MRI images classification so that it can be used to diagnose patients and *** classification is one of the prominent subset topics of machine learning and data mining that the most important image technique is the auto-categorization of *** images with high resolution and appropriate accuracy allow physicians to decide on the diagnosis of various diseases and treat *** auto categorization of MRI images toward diagnosing brain diseases has been being used to accurately diagnose hospitals,clinics,physicians and medical research *** this paper,an effective method is proposed for categorizing MRI images,which emphasizes the classification *** this method,images have been firstly collected and tagged,and then the discrete wavelet transform method has been implemented to extract the relevant *** the ready features in a matrix will be subsequently held,and PCA method has been applied to reduce the features ***,a new model using support vector machine classifier with radial basis function kernel ***+RBF has been *** SVM Algorithm must bimanually initialized,while,these values have been automatically entered into the SVM classifier by Salp Swarm Algorithm(SSA):Due to high performance of SSA in fast and accurate solution of nonlinear problem as compared to other optimization algorithms,it has been applied to optimally solve the designed ***,after applying the optimal parameters and SVM classification training,the test data has been utilized and *** results have transparently suggested the effectiveness of the proposed method in the Accuracy criteria with 0.9833,the Sensitivity with 1,Specificity with 0.9818 and Error with 0.0167 in best iteration as compared to the conventional SVM method.

关键词： Image classification optimization algorithm SVM RBF SSA

Effects of Polypropylene Fibers on the Physical and Mechanical Properties of Recycled Aggregate Concrete

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1327-1344页

作者： Pierre Matar Gérard-Philippe Zéhil Lebanese University Faculty of EngineeringBranch 2RoumiehLebanon Notre Dame University-Louaize Faculty of EngineeringZouk MosbehLebanon

The viability of using polypropylene fibers(PPF) in concrete was largely studied. Yet, few of the existing research studies investigated the effects of PPF on the properties of concrete containing recycled concrete aggregate(RCA). Mixes with different RCA replacement ratios and different PPF content were designed and tested. The test results showed that the addition of PPF did not change significantly the compressive strength and the density of the concrete, but slightly decreased its modulus of elasticity and Poisson’s ratio. The drop in the splitting tensile strength and the flexural strength due to RCA inclusions was to a large extent compensated by the PPF addition. The water absorption decreased and the percent voids increased with increased PPF addition. Correlations between the RCA content, the PPF content and the properties of concrete were studied. Useful regression models were proposed to predict the properties of concrete in relevant ranges of RCA and PPF content.

关键词： concrete recycled aggregate fiber reinforcement physical properties mechanical properties

A near-shore clastic-carbonate mixing mode in a continental rift basin(early Oligocene,eastern Shijiutuo Uplift,Bohai Bay Basin,China):sedimentology,reservoir characteristics and exploration practice

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Journal of Palaeogeography 2020年第4期9卷 438-455页

作者： Xiao-Feng Du Hao Liu Xiao-Bo Huang Zhang-Qiang Song Wei Xu Can Zhang China National offshore Oil Corporation Tianjin BranchTianjin 300459 School of Ocean Sciences China University of GeosciencesBeijing 100083

A comprehensive sedimentary and reservoir analysis was conducted based on seismic,well logging,core and relative test data,taking Members 1 and 2 of Shahejie Formation of the early Oligocene in the steep slope belt,eastern Shijiutuo Uplift(STU),Bohai Bay Basin(BBB)as a *** study indicates that a near-shore mixed fan deposit formed in the study area and developed characteristics and pattern of a high-quality *** mixed clastic-carbonate rocks constitute Members 1 and 2 of Shahejie Formation which developed along the steep slope belt and is named as a near-shore mixed *** mixed fan of the study area is mainly composed of microfacies of proximal channel,mixed deposited channel,mixed clastic beach,mixed bioclastic(grain)beach,with vertical multi-stage superimposition feature,and basically a similar shape as modern near-shore *** constitutes a new depositional type developing in the steep slope belt of a characteristic and complex lacustrine rift basin in the study *** mixed fan in the steep slope of eastern STU is controlled by comprehensive factors including tectonics,clastic material supply,climate,palaeogeomorphology and hydrodynamic *** reservoir quality of Members 1 and 2 of Shahejie Formation of eastern STU is,however,actually controlled by the sedimentary environment and diagenesis ***-grained mixed rocks of near-shore fans,rich in bioclastics,can form excellent reservoirs,characterized by resistance to compaction,easy to dissolution,little influenced by burial depth and high production of oil and gas,which enable them become key exploration targets of medium-deep strata of *** of high-quality reservoir,its controlling factors and the oil and gas exploration implications of the near-shore mixed fan developing in the study area give a deeper insight into discussions of the same type of mixed rocks of other lacustrine rift basins worldwide.

关键词： early Oligocene eastern Shijiutuo Uplift Bohai Bay Basin continental rift basin mixed carbonate-siliciclastic fan high-quality reservoirs

Erosion processes in karst landscapes of the Russian plain northern taiga,based on digital elevation modeling

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Journal of Mountain Science 2016年第4期13卷 569-580页

作者： Elena POLYAKOVA Mikhail GOFAROV Yuriy KUTINOV Vladimir BELJAEV Zinaida CHISTOVA Nikolay NEVEROV Vadim STARITSYN Alexandr MINEEV Sergey DURYNIN Institute of Ecological Problems of the North Ural Branch of Russian Academy of SciencesGeological Structure and Dynamics of the Lithosphere Laboratory Space Monitoring of the Arctic Centre of the Northern Arctic Federal University namedafter M.V.Lomonosov Arkhangelsk163000Russia Institute of Ecological Problems of the North Ural Branch of Russian Academy of SciencesMolecular Ecology and Biogeography LaboratoryArkhangelsk163000Russia Institute of Ecological Problems of the North Ural Branch of Russian Academy of SciencesGeological Structure and Dynamics of the Lithosphere LaboratoryArkhangelsk163000Russia

This paper considers the problems of the potential development of erosion processes in the natural landscapes of northern taiga in the Russian plain. It is considered that in forest ecosystems, erosion processes are slow and are weakly reflected in the terrain. However, the situation changes radically if the vegetation cover integrity is violated, which is inevitable with the modern methods of developing northern territories. Furthermore, global changes in average annual temperatures and the occurrence of karst processes may be the reason behind the development of erosion processes. The authors suggest a method for determining territories with a varying occurrence probability of erosional processes, based on digital elevation modelling. The territory of the Pinezhsky Nature Reserve(Arkhangelsk region) was chosen as the test plot. Direct field studies were previously used to detect exogenous geological processes in this territory. The authors were the first to suggest digital elevation modelling as a method that allows determining the potential danger of erosion in karst landscapes of the northern taiga. The geomorphometric studies resulted in the determination of areas with the greatest and lowest occurrence probability of erosion processes in the Pinezhsky Nature Reserve. It was established that the most significant erosion type was linear erosion, represented by incised river valleys and karst ravines. Sheet erosion is less significant and occurs as sinkholes, local declines, and chasms over the valleys of subterranean rivers.

关键词： Russian plain Erosion processes Karst Northern taiga Digital elevation model Geomorphometric parameters