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Optical coherence tomography angiography in diabetic retinopathy: a review of current applications

中国运筹学会第九届学术交流会

作者： Elise del Rosario 11 eastwood ave Eastwood City Cyberpark LibisQuezon City 1110Philippines

The International Federation of Operational Research Societies(IFORS) celebrates 50 years of service to the OR *** up to develop operations research as a unified science and to advance it in all the nations of the world,the organization sponsors international meetings,facilitates exchange of information on operational research,encourages

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Eye and Vision 2019年第1期6卷 312-321页

作者： Kai Yuan Tey Kelvin Teo Anna C.S.Tan Kavya Devarajan Bingyao Tan Jacqueline Tan Leopold Schmetterer Marcus Ang Hobart Clinical School Level 343 Collins StreetHobartTAS 7000Australia Singapore National Eye Centre 11 Third Hospital AveSingapore 168751Singapore Singapore Eye Research Institute 20 College Road Discovery TowerLevel 6 The AcademiaSingapore 169856Singapore Singapore National Eye Centre 11 Third Hospital AveSingapore 168751Duke-NUS Medical School8 College RdSingapore 169857Singapore

Background:Diabetic retinopathy(DR)is a leading cause of vision loss in ***,the standard imaging technique to monitor and prognosticate DR and diabetic maculopathy is dye-based *** the introduction of optical coherence tomography angiography(OCTA),it may serve as a potential rapid,non-invasive imaging modality as an *** text:Recent studies on the role of OCTA in DR include the use of vascular parameters e.g.,vessel density,intercapillary spacing,vessel diameter index,length of vessels based on skeletonised OCTA,the total length of vessels,vascular architecture and area of the foveal avascular *** quantitative measures may be able to detect changes with the severity and progress of DR for clinical *** may also serve as a non-invasive imaging method to detect diabetic macula ischemia,which may help predict visual ***,there are many limitations of OCTA in DR,such as difficulty in segmentation between superficial and deep capillary plexus;and its use in diabetic macula edema where the presence of cystic spaces may affect image *** applications of OCTA in the anterior segment include detection of anterior segment ischemia and iris neovascularisation associated with proliferative DR and risk of neovascular ***:OCTA may potentially serve as a useful non-invasive imaging tool in the diagnosis and monitoring of diabetic retinopathy and maculopathy in the *** studies may demonstrate how quantitative OCTA measures may have a role in detecting early retinal changes in patients with diabetes.

关键词： Optical coherence tomography angiography Fluorescein angiography Diabetic retinopathy Screening Monitoring

The Study of the Graft Hemodynamics with Different Instant Patency in Coronary Artery Bypassing Grafting

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Computer Modeling in Engineering & Sciences 2018年第8期116卷 229-245页

作者： Zhou Zhao Boyan Mao Youjun Liu Haisheng Yang Yu Chen Cardiac Surgery Department Peking University People’s Hospital.11th.Ave.XizhimenBeijingChina. College of Life Science and Bio-engineering Beijing University of Technology.No.100 PingleyuanChaoyang DistrictBeijingChina.

In coronary artery bypass grafting(CABG),graft’s poor instant patency may lead to an abnormal hemodynamic environment in anastomosis,which could further cause graft failure after the *** paper investigates the graft hemodynamics with different instant patency,and explores its effect on graft postoperative *** CABG 0D/3D coupling multi-scale models which used left internal mammary artery(LIMA)and saphenous vein(SVG)as grafts were *** types of grafts were examined in the models,including normal grafts,grafts with competitive flow and grafts with anastomotic *** results indicated that comparing with SVG grafts,there was a greater difference between normal LIMA graft and non-patent LIMA ***,the backflow occurred even in LIMA systolic *** wall shear stress(WSS)in the graft of the competitive flow LIMA model had an appreciable decrease comparing with the normal *** addition,the WSS in the stenosis region of the anastomotic stenosis LIMA model was much higher than its adjacent *** contrast,the WSS distributions in the SVG models were much smoother than in the LIMA *** oscillatory shear index(OSI),there was little difference between normal LIMA and *** when the graft had competitive flow or anastomotic stenosis,much higher OSI occurred in some regions in LIMA than *** are significant differences in hemodynamics between normal grafts and non-patent grafts both in LIMA and *** hemodynamic environment in a normal LIMA is better than that in a normal ***,in the situation of the two types of non-patent grafts,the hemodynamics of SVG is better than LIMA.

关键词： Coronary artery bypass grafting instant patency graft flow hemodynamics multi-scale model

Sm–Co high-temperature permanent magnet materials

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Chinese Physics B 2019年第1期28卷 5-24页

作者： Shiqiang Liu 240 Jackson ave. Braselton GA 30517 USA

Permanent magnets capable of reliably operating at high temperatures up to ~450?C are required in advanced power systems for future aircrafts, vehicles, and ships. Those operating temperatures are far beyond the capability of Nd–Fe–B magnets. Possessing high Curie temperature, Sm–Co based magnets are still very important because of their hightemperature capability, excellent thermal stability, and better corrosion resistance. The extensive research performed around the year 2000 resulted in a new class of Sm_2(Co, Fe, Cu, Zr)_(17)-type magnets capable of operating at high temperatures up to 550?C. This paper gives a systematic review of the development of Sm–Co permanent magnets, from the crystal structures and phase diagrams to the intrinsic magnetic properties. An emphasis is placed on Sm_2(Co, Fe, Cu, Zr)_(17)-type magnets for operation at temperatures from 300?C to 550?C. The thermal stability issues, including instantaneous temperature coefficients of magnetic properties, are discussed in detail. The significance of nanograin structure, nanocrystalline, and nanocomposite Sm–Co magnet materials, and prospects of future rare-earth permanent magnets are also given.

关键词： Sm–Co Sm2(Co,Fe,Cu,Zr)17 high-temperature magnets nanocomposite

Microstructure and mechanical properties of novel Al-Y-Sc alloys with high thermal stability and electrical conductivity

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Journal of Materials Science & Technology 2020年第1期36卷 1-6页

作者： A.V.Pozdniakov R.Yu.Barkov NUST"MISiS" Leninskiy ave.4119049MoscowRussia

The microstructure and mechanical properties of novel Al-Y-Sc alloys with high thermal stability and electrical conductivity were *** Al3 Y-phase particles of size 100-200 nm were detected in the as-cast microstructure of the ***3 Y-phase particles provided a higher hardness to as cast alloys than homogenized alloys in the temperature range of 370-440℃.L12 precipitates of the Al3(ScxYy) phase were nucleated homogenously within the aluminium matrix and heterogeneously on the dislocations during annealing at 400℃.The average size of the L12 precipitates was 11±2 nm after annealing for 1 h,and 25-30 nm after annealing for 5 h,which led to a decrease in the hardness of the Al-0.2 Y-0.2 Sc alloy to15 *** recrystallization temperature exceeded 350℃and 450℃for the Al-0.2 Y-0.05 Sc and Al-0.2 Y-0.2 Sc alloys,*** investigated alloys demonstrated good thermal stability of the hardness and tensile properties after annealing the rolled alloys at 200 and 300℃,due to fixing of the dislocations and grain boundaries by L12 precipitates and eutectic Al3 Y-phase *** good combination of strength,plasticity,and electrical conductivity of the investigated Al-0.2 Y-0.2 Sc alloys make it a promising candidate for electrical *** alloys exhibited a yield stress of 177-183 MPa,ultimate tensile stress of 199-202 MPa,elongation of 15.2-15.8%,and electrical conductivity of 60.8%-61.5% IACS.

关键词： Aluminium alloys Scandium Yttrium Recrystallization Mechanical properties Electrical conductivity

TransPolymer: a Transformer-based language model for polymer property predictions

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npj Computational Materials 2023年第1期9卷 1703-1716页

作者： Changwen Xu Yuyang Wang Amir Barati Farimani Department of Materials Science and Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Department of Mechanical Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Machine Learning Department Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA Department of Chemical Engineering Carnegie Mellon University5000 Forbes AvePittsburgh 15213 PAUSA

Accurate and efficient prediction of polymer properties is of great significance in polymer ***,expensive and time-consuming experiments or simulations are required to evaluate polymer ***,Transformer models,equipped with self-attention mechanisms,have exhibited superior performance in natural language ***,such methods have not been investigated in polymer ***,we report TransPolymer,a Transformer-based language model for polymer property *** proposed polymer tokenizer with chemical awareness enables learning representations from polymer *** experiments on ten polymer property prediction benchmarks demonstrate the superior performance of ***,we show that TransPolymer benefits from pretraining on large unlabeled dataset via Masked Language *** results further manifest the important role of self-attention in modeling polymer *** highlight this model as a promising computational tool for promoting rational polymer design and understanding structure-property relationships from a data science view.

关键词： property polymer rational

Analysis of shock wave reflection from fixed and moving boundaries using a stabilized particle method

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Particuology 2009年第5期7卷 373-383页

作者： Hassan Ostad Soheil Mohammadi School of Civil Engineering University of TehranEnghelab Ave.TehranIran

In the present paper, the efficiency of an enhanced formulation of the stabilized corrective smoothed particle method （CSPM） for simulation of shock wave propagation and reflection from fixed and moving solid boundaries in compressible fluids is investigated. The Lagrangian nature and its accuracy for imposing the boundary conditions are the two main reasons for adoption of CSPM. The governing equations are further modified for imposition of moving solid boundary conditions. In addition to the traditional artificial viscosity, which can remove numerically induced abnormal jumps in the field values, a velocity field smoothing technique is introduced as an efficient method for stabilizing the solution. The method has been implemented for one- and two-dimensional shock wave propagation and reflection from fixed and moving boundaries and the results have been compared with other available solutions. The method has also been adopted for simulation of shock wave propagation and reflection from infinite and finite solid boundaries.

关键词： CSPM Meshfree particle method Shock wave propagation and reflection Moving boundaries Compressible fluids Velocity field smoothing stabilization

Exact Solutions of the Dirac Equation for an Electron in a Magnetic Field with Shape Invariant Method

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Chinese Physics Letters 2008年第11期25卷 3848-3851页

作者： M. R. Setare O. Hatami Department of Science University of Kurdistan Pasdaran Ave. Sanandaj Iran

Based on the shape invariance property we obtain exact solutions oI the Dirac equation for an electron moving in the presence of a certain varying magnetic field, then we also show its non-relativistic limit.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Enduring effect of permeability texture for enhancing accuracy and reducing uncertainty of reservoir fluid flow through porous media

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Petroleum Science 2020年第1期17卷 118-135页

作者： Arash Azamifard Fariborz Rashidi Mohammadreza Pourfard Mohammad Ahmadi Bahram Dabir Department of Petroleum Engineering Amirkabir University of Technology424 Hafez AveTehranIran Department of Chemical Engineering Amirkabir University of Technology424 Hafez AveTehranIran Department of Electrical Engineering Amirkabir University of Technology424 Hafez AveTehranIran

Modeling reservoir permeability is one of the crucial tasks in reservoir simulation ***,it is done by kriging-based *** rigorous modeling of the permeability results in more reliable outputs of the reservoir ***,a new category of geostatistical methods has been used for this purpose,namely multiple point statistics(MPS).By this new category of permeability modeling methods,one is able to predict the heterogeneity of the reservoir permeability as a continuous *** methods consider the direction of property variation in addition to the distances of known locations of the *** this study,the reservoir performance of a modified version of the SPE 10 solution project as a pioneer case is used for investigating the efficiency of these methods and paralleling them with the kriging-based *** this way,the permeability texture concept is introduced by applying some MPS *** study is accomplished in the conditions of real reservoir dimensions and velocities for the whole reservoir life.A continuous training image is used as the input of calculation for the permeability *** results show that the detailed permeability of the reservoir as a continuous variable makes the reservoir simulation show the same fluid front movement and flooding behavior of the reservoir similar to the reference case with the same permeability *** MPS methods enable the reservoir simulation to reproduce the fluid flow complexities such as bypassing and oil trapping during water flooding similar to the reference ***,total oil production is predicted with higher accuracy and lower *** studied cases are identical except for the permeability *** histograms and variograms of permeabilities for the studied reservoir are quite similar,but the performance of the reservoir shows that kriging-based method results have slightly less accuracy than some MPS ***,it results in lower

关键词： Multiple point statistics Permeability modeling Fluid flow in porous media Permeability texture