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Estimating Network Connectedness of Financial Markets and Commodities

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Journal of Systems Science and Systems Engineering 2020年第5期29卷 572-589页

作者： ehsan Bagheri seyed Babak Ebrahimi Financial Engineering Group Faculty of Industrial EngineeringK.N.Toosi University of TechnologyTehranIran

We investigate the directional volatility and return network connectedness among stock,commodity,bond,currency and cryptocurrency *** period of study covers Feb 2006 until August *** utilize and expand Diebold and Yilmaz(20142015)connectedness measurement;accordingly,in the variance decomposition structure,we use Hierarchical Vector Autoregression(HVAR)to estimate high dimensional networks more *** empirical results show that markets are highly connected,especially during *** stock markets are the net receiver of shocks,while European and American stock markets are the net transmitter of shocks to other *** pairwise connectedness results suggest that among stock markets,DAX-CAC 40,FTSE 100-CAC 40 and S&P 500-S&P_TSX index are more integrated through connectedness than the *** other markets,WTI crude oil-Brent crude oil,30-Year bond and 10-Year bond,Dollar Index futures-EUR/USD have notable *** terms of cryptocurrencies,they contribute insignificantly to other markets and are highly integrated with each *** and cryptocurrencies seem to be good choices for investors to hedge during a crisis.

关键词： Financial markets network connectedness econometrics commodity

Droplets diameter distribution using maximum entropy formulation combined with a new energy-based sub-model

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Chinese Journal of Chemical Engineering 2016年第11期24卷 1625-1630页

作者： seyed Mostafa Hosseinalipour Hadiseh Karimaei ehsan Movahednejad Energy and Environmental Lab Dpt Mech. Eng. Iran University of Science and Technology 16846-13114 Narmak Tehran lran University of California Berkeley USA

The maximum entropy principle(MEP) is one of the first methods which have been used to predict droplet size and velocity distributions of liquid sprays. This method needs a mean droplets diameter as an input to predict the droplet size distribution. This paper presents a new sub-model based on the deterministic aspects of liquid atomization process independent of the experimental data to provide the mean droplets diameter for using in the maximum entropy formulation(MEF). For this purpose, a theoretical model based on the approach of energy conservation law entitled energy-based model(EBM) is presented. Based on this approach, atomization occurs due to the kinetic energy loss. Prediction of the combined model(MEF/EBM) is in good agreement with the available experimental data. The energy-based model can be used as a fast and reliable enough model to obtain a good estimation of the mean droplets diameter of a spray and the combined model(MEF/EBM) can be used to well predict the droplet size distribution at the primary breakup.

关键词：液滴直径分布子模型熵公式新能源能量守恒定律液滴尺寸分布最大熵原理模型预测

Three-Dimensional Numerical Investigation of the Separation Process in a Vortex Tube at Different Operating Conditions

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Journal of Marine Science and Application 2016年第2期15卷 157-165页

作者： seyed ehsan Rafiee M.M. Sadeghiazad Department of Mechanical Engineering Urmia University of Technology Urmia P.O. Box 57155-419 Iran

空气隔板提供安全、干净、适当的空气流动给引擎并且广泛地与象轮船和潜水艇那样的大引擎在车辆被使用。在这运作的研究，在清洗的一个 Ranque-Hilsch 旋涡试管内的分离进程(冷却) 系统被调查在旋涡试管性能上分析操作煤气的类型的影响... 详细信息

空气隔板提供安全、干净、适当的空气流动给引擎并且广泛地与象轮船和潜水艇那样的大引擎在车辆被使用。在这运作的研究，在清洗的一个 Ranque-Hilsch 旋涡试管内的分离进程(冷却) 系统被调查在旋涡试管性能上分析操作煤气的类型的影响；使用的操作气体是空气，氮，氧，二氧化碳和氮二氧化物。动态模型使用了的计算液体与三维的结构被装备，并且不变的条件在计算期间被使用。标准 k- 骚乱模特儿被雇用解决非线性的流动方程，和各种各样的关键参数，例如热、冷用尽热落下，并且驱动分离率，数字地被描述。结果证明氮二氧化物创造最大的分离从测试的所有气体的力量，和数字结果被对可得到的试验性的数据的好同意验证。另外，比较在二个不同边界条件， pressure-far-field 和压力插头的使用之间被做，当在空气隔板内分析复杂狂暴的流动时。结果在未来为使用介绍一个全面、实际的答案数字研究。

关键词：分离过程数值研究三维结构涡流管空气分离器流体动力学模型非线性渗流方程大型发动机

Experimental Study and 3D CFD Analysis on the Optimization of Throttle Angle for a Convergent Vortex Tube

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Journal of Marine Science and Application 2016年第4期15卷 388-404页

作者： seyed ehsan Rafiee M.M.Sadeghiazad Department of Mechanical Engineering Urmia University of Technology Urmia P. O. Box 57155- 4191-ran

会聚类型的旋涡试管(vt ) 与的七调整不同扼杀角度被使用。调整被做在 vt 内在冷、热的温度落下以及流动结构上分析如此的角度的影响。试验性的安装被设计，并且测试在从 0.45 ～ 0.65 MPa 的注射压力在不同会聚的 vt 配置上被执行。thr... 详细信息

会聚类型的旋涡试管(vt ) 与的七调整不同扼杀角度被使用。调整被做在 vt 内在冷、热的温度落下以及流动结构上分析如此的角度的影响。试验性的安装被设计，并且测试在从 0.45 ～ 0.65 MPa 的注射压力在不同会聚的 vt 配置上被执行。throttle 阀门的角度在 30 湯愠 ? 桴 ? 潮据癯污湥 ? 湩整慲瑣潩 ? 潤潮之间被安排吗？？

关键词：会聚的旋涡试管圆锥形的阀门角度注射压力槽数优化

Enucleation and evisceration: indications, complications and clinicopathological correlations

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International Journal of Ophthalmology(English edition) 2014年第4期7卷 677-680页

作者： Ali Kord Valeshabad Masood Naseripour Rajab Asghari seyed Hamid Parhizgar seyed ehsan Parhizgar Mohammad Taghvaei Shahin Miri Department of Ophthalmology and Visual Sciences University of Illinois at Chicago Department of Ophthalmology Eye Research CenterRassoul Akram Hospital Iran University of Medical Sciences School of Medicine Tehran University of Medical Sciences Department of Ophthalmology Baqiyatallah University of Medical Sciences Department of Neurosurgery Imam Khomeini HospitalTehran University of Medical Sciences

·AIM: To assess main indications, postoperative complications and clinicopathological correlation of ocular enucleation-evisceration.·METHODS: A total of 107 subjects who underwent enucleation and/or evisceration and received hydroxyapatite implants(Scleral wrap or mesh) were assessed. For each patient clinicopathological data was collected which included demographic information,clinical history, primary clinical diagnosis, main cause of ophthalmic surgery(traumatic, non-traumatic), type of surgical procedure(enucleation, evisceration) and pathological report. Patients’ postoperative clinical visits were checked for procedure-related complications during first year after surgery.·RESULTS: One hundred and seven patients(male:65.4%; mean age: 26y) underwent enucleation(n=100) or evisceration(n =7) due to traumatic(n =41) and non-traumatic(n =66) causes. Disfiguring painful blind eye was the most common indication of surgery(66.4%),followed by leukocoria(19.6%) and endophthalmitis(4.7%). The main types of injury included firecracker,traffic and work accidents, and sharp object perforating injury. In 53(80.3%) subjects in non-traumatic group the initial clinical diagnosis matched the histopathologicalresults. Malignant tumors(retinoblastoma: 47.5%,malignant melanoma: 27.3%) were the most common pathological diagnoses followed by phthisis bulbi(25.8%).The most common procedure-related complications were major eye discharge(39.6%), and implant exposure and discharge(20.8%).·CONCLUSION: Trauma and malignant tumors are the leading causes of enucleation-evisceration. Despite developing new techniques and materials, enucleation is still associated with considerable postoperative complications.

关键词： enucleation evisceration retinoblastoma malignant melanoma ocular injury

Phylogeography,genetic variability and structure of Acanthamoeba metapopulations in Iran inferred by 18S ribosomal RNA sequences:A systematic review and meta-analysis

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Asian Pacific Journal of Tropical Medicine 2017年第9期10卷 855-863页

作者： Adel Spotin Hamid Reza Moslemzadeh Mahmoud Mahami-Oskouei ehsan Ahmadpour Maryam Niyyati seyed Hossein Hejazi Fatemeh Memari Jafar Noori Immunology Research Center Tabriz University of Medical SciencesTabrizIran Department of Parasitology and Mycology Faculty of MedicineTabriz University of Medical SciencesTabrizIran Department of Medical Parasitology and Mycology School of MedicineShahid Beheshti University of Medical SciencesTehranIran Department of Parasitology and Mycology School of MedicineIsfahan University of Medical SciencesIsfahanIran

Objective: To verify phylogeography and genetic structure of Acanthamoeba populations among the Iranian clinical isolates and natural/artificial environments distributed in various regions of the ***: We searched electronic databases including Medline, Pub Med, Science Direct, Scopus and Google Scholar from 2005 to 2016. To explore the genetic variability of Acanthamoeba sp, 205 sequences were retrieved from keratitis patients, immunosuppressed cases and environmental sources as of various geographies of ***: T4 genotype was the predominant strain in Iran, and the rare genotypes belonged to T2, T3, T5(Acanthamoeba lenticulata), T6, T9, T11, T13 and T15(Acanthamoeba jacobsi).A total of 47 unique haplotypes of T4 were identified. A parsimonious network of the sequence haplotypes demonstrated star-like feature containing haplogroups IR6(34.1%) and IR7(31.2%) as the most common haplotypes. In accordance with the analysis of molecular variance, the high value of haplotype diversity(0.612–0.848) of Acanthamoeba T4 represented genetic variability within populations. Neutrality indices of the 18 S ribosomal RNA demonstrated negative values in all populations which represented a considerable divergence from neutrality. The majority of genetic diversity belonged to the infected contact lens and dust samples in immunodeficiency and ophthalmology wards, which indicated potential routes for exposure to a pathogenic Acanthamoeba sp. in at-risk individuals. A pairwise fixation index(FST) was from low to high values(0.024 33–0.418 92). The statistically FST points out that T4 is genetically differentiated between north-west, north-south and centralsouth metapopulations, but not differentiated between west-central, west-south, centralsouth, and north-central ***: An occurrence of IR6 and IR7 displays that possibly a gene flow of Acanthamoeba T4 occurred after the founder effect or bottleneck experience through ecological changes or host mobility

关键词： Acanthamoeba metapopulations 基因可变性基因流动分子的发展史伊朗

Zero-Inflated Negative Binomial Regression Model with Right Censoring Count Data

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材料科学与工程（中英文B版） 2011年第4期1卷 551-554页

作者： seyed ehsan Saffari Robiah Adnan Department of Mathematics Faculty of Science Universiti Teknologi Malaysia Malaysia

A Poisson model is typically assumed for count data, but when there are so many zeros in the response variable, because of overdispersion, a negative binomial regression is suggested as a count regression instead of Poisson regression. In this paper, a zero-inflated negative binomial regression model with right censoring count data is developed. In this model, we consider a response variable and one or more than one explanatory variables. The estimation of regression parameters using the maximum likelihood method is discussed and the goodness-of-fit for the regression model is examined. We study the effects of censoring in terms of parameters estimation and their standard errors via simulation.

关键词：回归模型计数资料二项式零膨胀估计标准误差泊松模型最大似然法模型开发

Improvement of Mining Fuzzy Multiple-Level Association Rules from Quantitative Data

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Journal of Software Engineering and Applications 2012年第3期5卷 190-199页

作者： Alireza Mirzaei Nejad Kousari seyed Javad Mirabedini ehsan Ghasemkhani Department of Computer Science Central Tehran Branch Islamic Azad University Tehran Iran Department of Computer Science East Tehran (Ghiamdasht) Branch Islamic Azad University Tehran Iran

Data-mining techniques have been developed to turn data into useful task-oriented knowledge. Most algorithms for mining association rules identify relationships among transactions using binary values and find rules at a single-concept level. Extracting multilevel association rules in transaction databases is most commonly used in data mining. This paper proposes a multilevel fuzzy association rule mining model for extraction of implicit knowledge which stored as quantitative values in transactions. For this reason it uses different support value at each level as well as different membership function for each item. By integrating fuzzy-set concepts, data-mining technologies and multiple-level taxonomy, our method finds fuzzy association rules from transaction data sets. This approach adopts a top-down progressively deepening approach to derive large itemsets and also incorporates fuzzy boundaries instead of sharp boundary intervals. Comparing our method with previous ones in simulation shows that the proposed method maintains higher precision, the mined rules are closer to reality, and it gives ability to mine association rules at different levels based on the user’s tendency as well.

关键词： Association Rule Data Mining Fuzzy Set Quantitative Value Taxonomy

克罗恩病的神经系统表现:疾病诊治的有益补充

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Gastroenterology Report 2019年第4期7卷 291-297,I0002页

作者： Reza Nemati Somayeh Mehdizadeh Hooman Salimipour ehsan Yaghoubi Zeinab Alipour seyed Masoud Tabib Majid Assadi Department of Neurology Bushehr University of Medical SciencesBushehrIran The Persian Gulf Tropical Medicine Research Center Bushehr University of Medical SciencesBushehrIran Department of Pathology Rasul-e Akram HospitalIran University of Medical SciencesTehranIran Department of Neurology Yasuj University of Medical SciencesYasujIran Department of Gastroenterology and Hepatology Bushehr University of Medical SciencesBushehrIran The Persian Gulf Nuclear Medicine Research Center Bushehr University of Medical SciencesBushehrIran

The neurological manifestations of Crohn’s disease and its prevalence are not well ***,we report five patients of confirmed Crohn’s disease with different neurological *** neurological presentations include anterior ischemic optic neuropathy,myelopathy,posterior reversible encephalopathy syndrome,chronic inflammatory demyelinating polyneuropathy,and chronic axonal sensory and motor *** manifestations should be kept in mind in the assessment of Crohn’s disease.

关键词： Crohn’s disease idiopathic inflammatory bowel disease neurological manifestation