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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： d.V.dUNG d.T.dONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. Theoretical formulations are derived by the third-order shear deformation theory （TSdT） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. The explicit expressions for determining the critical buckling load.a.d the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. Two iterative algorithms are presented. The effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sandwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation

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国外若干铁矿勘探概况

地质与勘探 1976年第2期 76-86页

作者：邵登仁 d.a.汉森

北欧三国瑞典全部可开采的铁矿,均位于芬诺斯堪第安前寒武系地盾的两个铁矿区中(图1).在伯格斯拉根老矿区,平均含铁33%的含石英条带的矿石是最广泛的,其次是磷灰石矿石(57%Fe)和夕卡岩或灰岩矿石(33%Fe).在拉普兰铁矿区,基鲁纳型的磷灰... 详细信息

北欧三国瑞典全部可开采的铁矿,均位于芬诺斯堪第安前寒武系地盾的两个铁矿区中(图1).在伯格斯拉根老矿区,平均含铁33%的含石英条带的矿石是最广泛的,其次是磷灰石矿石(57%Fe)和夕卡岩或灰岩矿石(33%Fe).在拉普兰铁矿区,基鲁纳型的磷灰石矿石最多(60%Fe),许多夕卡岩矿石(40%Fe)和少量沉积矿石(34%Fe)也有所发现,但尚未开采.挪威和芬兰的铁矿床较少,图1标出了正在开采的矿山位置.丹麦仅有些极小的沼铁矿床.

关键词：铁矿床假象赤铁矿水赤铁矿黑色金属矿床矿石含铁石英岩碧玉铁质岩

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内镜下机器人辅助二尖瓣手术

世界核心医学期刊文摘（心脏病学分册） 2007年第2期3卷 61-62页

作者： Murphy d.a. Miller J.S. Langford d.a. Snyder A.B. 罗亮 department of Cardiothoracic Surgery Saint Joseph's Hospital of Atlanta Atlanta Ga United States.Dr.

目的:确定利用机器人设备经右胸行内镜下二尖瓣手术的安全性和有效性。方法:对2002年12月至2005年11月间接受内镜下机器人辅助二尖瓣手术的127例患者进行回顾性调查。患者年龄为54±13岁,其中58%为男性。121例患者的二尖瓣反流为4+,4例... 详细信息

目的:确定利用机器人设备经右胸行内镜下二尖瓣手术的安全性和有效性。方法:对2002年12月至2005年11月间接受内镜下机器人辅助二尖瓣手术的127例患者进行回顾性调查。患者年龄为54±13岁,其中58%为男性。121例患者的二尖瓣反流为4+,4例为3+,2例为2+。19例(15%)患者的左心室射血分数≤50%。

关键词：二尖瓣手术机器人系统二尖瓣反流左心室射血分数二尖瓣修复术二尖瓣置换术晚期死亡超声心动图

雷德卡烧结厂及其矿石中和场的设想、设计和实际应用

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烧结球团 1981年第3期 53-70页

作者： d.a.坎贝尔 ,d.里斯特 ,刘韬

英国钢铁公司关于铁矿石选矿和钢铁生产的经营方针是在沿海有限的某些能建深水矿石码头的地方建设诸如蒂兹赛德新厂。新增加的设备使炼铁能力增加到500万吨/年,进一步发展可使设计能力最大达1000万吨/年。高效率的高炉和炼钢实践的先决... 详细信息

英国钢铁公司关于铁矿石选矿和钢铁生产的经营方针是在沿海有限的某些能建深水矿石码头的地方建设诸如蒂兹赛德新厂。新增加的设备使炼铁能力增加到500万吨/年,进一步发展可使设计能力最大达1000万吨/年。高效率的高炉和炼钢实践的先决条件是必须提供高质量的稳定炉料,所以这项发展的主要部分是建设拥有中和矿石和混合设施的新的大型烧结厂。对于炉料化学成分的高度控制已通过矿石中和场和混合设施达到,这些设施辅以计算机控制并直接与物料的重量和试样的化学分析相联系。实践表明:这座烧结厂能较长期地连续生产,保证满足高炉的需要而很少出现悬料。在康塞特和克利夫兰厂,能够连续生产质最均匀的铁水,降低焦比,提高产量。工厂的设计要求业已超过,特别是在进行烧结生产和提高烧结矿质量时,降低了热能的需要。

关键词：烧结矿冷强度碱度人造富矿钢铁企业烧结厂混合料仓矿石

Pattern synthesis optimization of 3-d OdAR based on improved GA using LSFE method

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Journal of Harbin Institute of Technology(New Series) 2011年第1期18卷 96-100页

作者：龙伟军贲德 BAKHSHI ASIM d 张弓 College of Information Science and Technology Nanjing University of Aeronautics & Astronautics Computer Engineering University of Engineering and Technology

Pattern synthesis in 3-d opportunistic digital array radar(OdAR) becomes complex when a multitude of antennas are considered to be randomly distributed in a three dimensional *** order to obtain an optimal pattern,several freedoms must be constrained.a.new pattern synthesis approach based on the improved genetic algorithm(GA) using the least square fitness estimation(LSFE) method is *** optimized by this method include antenna locations,stimulus states and phase *** new algorithm demonstrates that the fitness variation tendency of GA can be effectively predicted.a.ter several "eras" by the LSFE *** is shown that by comparing the variation of LSFE curve slope,the GA operator can be adaptively modified to avoid premature convergence of the *** validity of the algorithm is verified using computer implementation.

关键词： antenna rad.a.ion patterns genetic algorithm(GA) opportunistic digital array radar(OdAR) pattern synthesis the least square fitness estimation(LSFE)

α-1抗胰蛋白酶缺失:遗传性肝脏疾病导致肝细胞癌的一种新范例

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世界核心医学期刊文摘（胃肠病学分册） 2006年第1期2卷 39-40页

作者： Rudnick d.a. Perlmutter d.H. 李翔 University of Pittsburgh School of Medicine Children’ s Hospital of Pittsburgh Department of Pediatrics 3705 Fifth Avenue Pittsburgh PA 15213 United States Dr.

Liver disease in alpha-1-antitrypsin (α 1AT) deficiency is caused by a gain-of-toxic function mechanism engendered by the accumulation of a mutant glycoprotein in the endoplasmic reticulum (ER). The extraordinary degree of variation in phenotypical expression of this liver disease is believed to be determined by genetic modifiers and/or environmental factors that influence the intracellular disposal of the mutant glycoprotein or the signal transduction pathways that are activated. Recent investigations suggest that a specific repertoire of signaling pathways are involved, including the autophagic response, mitochondrial-and ER-caspase activation, and nuclear factor kappa B (NFκ B) activation. Whether activation of these signaling pathways, presumably to protect the cell, inadvertently contributes to liver injury or perhaps protects the cell from one injury and, in so doing, predisposes it to another type of injury, such as hepatocarcinogenesis, is not yet known. Recent studies also suggest that hepatocytes with marked.a.cumulation of α 1ATZ, globule-containing hepatocytes, engender a cancer-prone state by surviving with intrinsic damage and by chronically stimulating in‘ trans’ ad.a.ent relatively undamaged hepatocytes that have a selective proliferative ad.a.tage. Further, this paradigm may apply to other genetic and infectious liver diseases that are predisposed to hepatocellular carcinoma.

关键词：肝脏疾病抗胰蛋白酶肝细胞癌肝脏损伤信号转导途径基因表型酶激活球状体变异程度遗传修饰

Kinematic error modeling and error compensation of desktop 3d printer

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Nanotechnology and Precision Engineering 2018年第3期1卷 180-186页

作者： Shane Keaveney Pat Connolly Eoin d.O'Cearbhaill School of Mechanical and Materials Engineering UCD Engineering and Materials Science CentreDublin 4Ireland

desktop 3d printers have revolutionized how designers and makers prototype and manufacture certain *** popular fuse deposition modeling(FdM)desktop printers have enabled.a.shift to low-cost consumer goods markets,through reduced capital equipment investment and consumable material ***,with this drive to reduce costs,the computer numerical control(CNC)systems implemented in FdM printers are often compromised by poor accuracy and contouring *** condition is most critical as users begin to use 3d-printed components in load-bearing applications or to perform mechanical *** methods of low-cost 3d printer calibration are needed before their open-design potential can be realized in applications,including 3d-printed orthotics and *** paper applies methodologies associated with high-precision CNC machining systems,namely,kinematic error modeling and compensation coupled with standardized test methods from ISO230-4,such as the ballbar for kinematic and dynamic error measurements,to examine the influence and feasibility for use on low-cost CNC/3d printing ***,the *** and drug Administration's"Technical considerations for additive manufactured medical devices"highlighted the need to develop standards specific to additive manufacturing in regulated manufacturing *** paper shows the benefits of the methods described within ISO230-4 for error assessment,alongside applying kinematic error modeling and compensation to the popular kinematic configuration of an Ultimaker 3d printer.A Renishaw ballbar QC10 is used to quantify the Ultimaker's errors and thereby populate the error *** method quantifies machine errors and populates these in a mathematical model of the CNC ***,a post-processor can be used to compensate the printing ***,the ballbar is used to demonstrate the d.a.atic impact of the error compensation model on the accuracy and contouring of the Ultimaker pr

关键词： 3d printing accuracy Kinematic error modeling Kinematic error compensation Ballbar FdM3d printing ISO230-4

接受胰岛素治疗的2型糖尿病患者非黑色素瘤皮肤癌的发生率下降:一项初步研究

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世界核心医学期刊文摘（皮肤病学分册） 2005年第12期1卷 43-44页

作者： Lewis d.a. Spandau d.F. 刘艳 dr. department of dermatology Indiana University Medical Center 975 West Walnut Street Indianapolis IN 46202- 5121 United States

Background: In order to prevent the propagation of genetic mutations, human keratinocytes irrad.a.ed with ultraviolet (UV) B light in vitro undergo premature stress- induced senescence or apoptosis. This response to UVB irrad.a.ion is dependent on the functional activation of the insulin- like growth factor- 1 receptor (IGF- 1R). Based on this in vitro functional data, we hypothesized that the increased serum levels of insulin in patients with type 2 d.a.etes may activate the IGF- 1R in skin and lead to a decreased frequency of skin cancer in these patients. Objectives: To determine whether the use of insulin by patients with type 2 d.a.etes correlated with a change in the incidence in nonmelanoma skin cancer (NMSC). Methods: A historical cohort study identifying the incidence of NMSC following the use of two different pharmacological therapies. The patient population was restricted to caucasians who were at least 50 years old when they began the indicated pharmacological therapy. The first group consisted of 1440 patients who used insulin therapy to treat type 2 d.a.etes and the second group comprised 4135 patients who used cimetidine to treat their gastrointestinal ailments. An additional group of 6131 patients with d.a.etes who used noninsulin antid.a.etics was added to examine the effect of noninsulin therapies. All patients had regular follow- up visits at the Regenstrief Clinics during the study period between 1980 and 1999. The Regenstrief Clinics is an outpatient facility which serves the general population in Metro- Ind.a.apolis, Ind.a.a, U.S.A. Results: The incidence of NMSC in patients using insulin was significantly lower than in patients using cimetidine (1.25% vs. 2.35% , P decrease in NMSC in patients with type 2 d.a.etes correlated specifically with the use of insulin (NMSC incidence insulin- only patients with d.a.etes: 1- 40% vs. those with d.a.etes using noninsulin therapies: 2- 35% , P=0.11). Conclusions: Patients using exogenous insu

关键词：角质形成细胞应激诱导基因突变队列研究患者群胃肠道疾病功能活性抗糖尿病药物功能数据高加索人

pde2path – A Matlab Package for Continuation and Bifurcation in 2d Elliptic Systems

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Numerical Mathematics(Theory,Methods and.a.plications) 2014年第1期7卷 58-106页

作者： Hannes Uecker daniel Wetzel Jens d.M.Rademacher Institut für Mathematik Universität Oldenburg26111 OldenburgGermany Universität Bremen Fachbereich MathematikPostfach 33044028359 BremenGermany

pde2path is a free and easy to use Matlab continuation/bifurcation package for elliptic systems of PdEs with arbitrary many components,on general two dimensional domains,and with rather general boundary *** package is based on the FEM of the Matlab pdetoolbox,and is explained by a number of examples,including Bratu’s problem,the Schnakenberg model,Rayleigh-Bénard convection,and von Karman plate *** serve as templates to study new problems,for which the user has to provide,via Matlab function files,a description of the geometry,the boundary conditions,the coefficients of the PdE,and.a.rough initial guess of a *** basic algorithm is a one parameter arclength-continuation with optional bifurcation detection and *** calculations,error control and mesh-handling,and some elementary timeintegration for the associated parabolic problem are also *** continuation,branch-switching,plotting etc are performed via Matlab command-line function calls guided by the AUTO *** software can be downloaded from ***/*** ker/pde2path,where also an online documentation of the software is provided such that in this paper we focus more on the mathematics and the example systems.

关键词： Elliptic systems continuation and bifurcation finite element method

Application and validation of a 3-d calcium,chloride,and sulfate model in Lake Okeechobee

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Ecological Processes 2014年第1期3卷 1-19页

作者： Kang-Ren Jin Mark d Shafer Zhen-Gang Ji Lead Scientist South Florida Water Management DistrictP.O.Box 24680West Palm BeachFL 33416-4680USA Senior Environmental Engineer US Army Corps Engineers701 San Marco BlvdJacksonvilleFL 32207-8175USA Adjunct Professor Department of Civil EngineeringCatholic University of AmericaPangborn HallRoom G12WashingtonDC 20064USA

Introduction: The calibration, verification, and validation of calcium (Ca), chloride (Cl), and sulfate (SO_(4)) module ofthe Lake Okeechobee Environment Model (LOEM) was completed. The integrated model could simulate Ca, Cl, andSO_(4) concentrations and transport due to wind driven currents and waves from 1 Oct 1999 to 30 Sept 2009 in LakeOkeechobee. The enhanced model was also used to estimate lake water quality effects resulting from differentmanagement scenarios that include discharges from planned.a.uifer storage and recovery (ASR) ***: The fate and transport processes of Ca, Cl, and SO_(4) are controlled by their reactivity and their hydrodynamictransport. Reactivity includes chemical, biological, and bio-uptake processes (IJRSA 33:2233-2260, 2012). Hydrodynamictransport includes advection of water current, diffusion, and turbulent mixing within the water column. The depositionand resuspension on the water-sediment bed interface is also included. The mathematical equations for describing Ca,Cl, and SO_(4) substances, including heavy metal and total organic carbon (TOC), are ***: Both the statistical results and the time series comparisons indicate that the simulation of Ca, Cl, and SO_(4) aregenerally simulated well by the LOEM. The root mean square error over the variance rage is Cl dSO_(4) d SO_(4) concentrations in the lake were largely controlled by water temperature and lakeevaporation. Inflows to the lake can also have localized effects on chloride variations. Shallow water depth and highevaporation contribute to high Cl/Ca/ SO_(4) concentration in the lake.

关键词： Ca Cl SO_(4)modeling Lake Okeechobee Long-term simulation Environmental modeling