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解弹性柱体声散射问题的有限元素法

声学技术 1981年第1期 53-68页

作者： John T.Hunt Max R.Knittel charles s.nichols Don Barach 蒋廷华海军水下中心

本文给出一种近似方法,解弹性体被浸在无限流体介质中的声散射运动方程,此处发表的数字模型是用有限元素法来计算弹性体的振动响应及靠近弹性体周围的有限体积介质的声压场。使用解析方法来获得这种数字模型的边界条件,对于平面声波垂... 详细信息

本文给出一种近似方法,解弹性体被浸在无限流体介质中的声散射运动方程,此处发表的数字模型是用有限元素法来计算弹性体的振动响应及靠近弹性体周围的有限体积介质的声压场。使用解析方法来获得这种数字模型的边界条件,对于平面声波垂直入射到铝园盘上的情况发表了总的声散射截面,轴向声压,散射指向性图等结果.

关键词：方程式项数方程圆盘结构函数有限元素法矩阵数学分析声散射结构模型结构范式粒子模型声压

Optimizing neoadjuvant radiotherapy for resectable and borderline resectable pancreatic cancer using protons

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World Journal of Gastrointestinal surgery 2019年第7期11卷 303-307页

作者： Romaine Charles.nichols Michael Rutenberg Department of Radiation Oncology University of Florida College of Medicine

Approximately 25%of patients diagnosed with pancreatic cancer present with non-metastatic resectable or borderline resectable ***,the cure rate for these“curable”patients is only in the range of 20%.Local-regional failure rates may exceed 50%after margin-negative,node-negative pancreatectomy,but up to 80%of resections are associated with regional lymph node or margin *** systemic drug therapy and chemotherapy may prevent or delay the appearance of distant metastases,it is unlikely to have a significant impact on local-regional disease *** radiotherapy would represent a rational intervention to improve local-regional *** barrier to preoperative radiotherapy is the concern that it could potentially complicate what is already a long and complicated *** the radiotherapy is delivered with X-rays(photons),the entire cylinder of the abdomen is irradiated;therefore,an operating surgeon may be reluctant to accept the associated risk of increased *** preoperative radiotherapy is delivered with protons,however,significant bowel and gastric tissue-sparing is achieved and clinical outcomes indicate that proton therapy does not increase the risk of operative complications nor extend the length of the procedure.

关键词： Radiation oncology Pancreatic cancer Proton therapy

Application of a water quality model for determining instream aeration station location and operational rules:A case study

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Water science and Engineering 2018年第1期11卷 8-16页

作者： charles s.Melching Melching Water solutions LLC GreenfieldWI 53221USA

Instream aeration has been used as a supplement to secondary treatment or a substitute for tertiary treatment for meeting dissolved oxygen （DO） standards in rivers. Many studies have used water quality models to determine the number, location, and capacity of instream aeration stations （IAss） needed to meet DO standards in combination with other pollution control measures. DO concentrations have been improved in the North shore Channel and North Branch Chicago River by the Devon Avenue IAs for more than 35 years. A study was initiated to determine whether it was better to rehabilitate or relocate this station and to determine appropriate operational guidance for the IAs at the selected location. A water quality model capable of simulating DO concentrations during unsteady flow was used to evaluate the proper location for an IAs and operational guidance for this IAs. Three test years, a dry year, a wet year, and an extreme year, were considered in the evaluation. The study found that the Devon Avenue IAs should be rehabilitated as this location performed as well as or better than any of 10 alternative locations. According to the new operational guidance for this IAs, the amount of time with blowers operating could be substantially reduced compared to traditional operations while at the same time the attainment of the DO standards could be increased. This study shows that a carefully designed modeling study is key to effective selection, location, and operation of IAss such that attainment of DO standards can be maximized while operation hours of blowers can be minimized.

关键词： Instream aeration Dissolved oxygen Water quality modeling Water quality management Computer simulation

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Numerical modelling of reinforced concrete flexural members strengthened using textile reinforced mortars

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Frontiers of structural and Civil Engineering 2023年第4期17卷 649-668页

作者： Naveen Revanna charles K.s.Moy Department of Civil Engineering Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China

Externally bonded(EB)and near-surface mounted(NsM)bonding are two widely adopted and researched strengthening methods for reinforced-concrete *** composite substrates are easy to reach and repair using appropriate surface treatments,whereas NsM techniques can be easily applied to the soffit and concrete member *** EB bonded fiber-reinforced polymer(FRP)technique has a significant drawback:combustibility,which calls for external protective agents,and textile reinforced mortar(TRM),a class of EB composites that is noncombustible and provides a similar functionality to any EB FRP-strengthened *** study employs a finite element analysis technique to investigate the failing failure of carbon textile reinforced mortar(CTRM)-strengthened reinforced concrete *** principal objective of this numerical study was to develop a finite element model and validate a set of experimental data in existing literature.A set of seven beams was modelled and calibrated to obtain concrete damage plasticity(CDP)*** predicted results,which were in the form of load versus deflection,load versus rebar strain,tensile damage,and compressive damage patterns,were in good agreement with the experimental ***,a parametric study was conducted to verify the applicability of the numerical model and study various influencing factors such as the concrete strength,internal reinforcement,textile roving spacing,and externally-applied load *** ultimate load and deflection of the predicted finite element results had a coefficient of variation(COV)of 6.02%and 5.7%,respectively.A strain-based numerical comparison with known methods was then conducted to investigate the debonding *** developed finite element model can be applied and tailored further to explore similar TRM-strengthened beams undergoing debonding,and the preventive measures can be sought to avoid premature debonding.

关键词： fiber reinforced polymer textile reinforced mortar finite element analysis concrete damage plasticity calibration and validation parametric study

Uniform Asymptotic Expansion of the Voltage Potential in the Presence of Thin Inhomogeneities with Arbitrary Conductivity

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Chinese Annals of Mathematics,series B 2017年第1期38卷 293-344页

作者： charles DAPOGNY Michael s.VOGELIUs Laboratoire Jean Kuntzmann CNRSUniversité Grenoble-Alpes Department of Mathematics Rutgers University

Asymptotic expansions of the voltage potential in terms of the "radius" of a diametrically small(or several diametrically small) material inhomogeneity(ies) are by now quite well-known. such asymptotic expansions for diametrically small inhomogeneities are uniform with respect to the conductivity of the *** contrast, thin inhomogeneities, whose limit set is a smooth, codimension 1 manifold,σ, are examples of inhomogeneities for which the convergence to the background potential,or the standard expansion cannot be valid uniformly with respect to the conductivity, a, of the inhomogeneity. Indeed, by taking a close to 0 or to infinity, one obtains either a nearly homogeneous Neumann condition or nearly constant Dirichlet condition at the boundary of the inhomogeneity, and this difference in boundary condition is retained in the *** purpose of this paper is to find a "simple" replacement for the background potential, with the following properties:(1) This replacement may be(simply) calculated from the limiting domain Ω\σ, the boundary data on the boundary of Ω, and the right-hand side.(2) This replacement depends on the thickness of the inhomogeneity and the conductivity,a, through its boundary conditions on σ.(3) The difference between this replacement and the true voltage potential converges to 0 uniformly in a, as the inhomogeneity thickness tends to 0.

关键词： Uniform asymptotic expansions Conductivity problem Thin inhomogeneities

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David Jones and charles Olson in Time and space

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Journal of Foreign Languages and Cultures 2020年第2期4卷 104-113页

作者： charles Alexander Chax Press/University of Houston-Victoria

David Jones and charles Olson concern themselves with large issues of space and time,and how humans are entwined with *** essay seeks to show that Olson's project of space and Jones's with time are very much of the same mettle,that both poems offer a kind of transcendence of one-dimensionality,that time expands to become space,and that,in space,one is confronted with the presence of all time as a *** essay addresses Jones's The Anathemata and a few of his maps and paintings,as well as Olson's Maximus Poems,particularly its visual/spatial poetics.

关键词： time space history map geography

Experimental evaluation of the effect of storm movement on peak discharge

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International Journal of sediment Research 2015年第2期30卷 167-177页

作者： Jin Liang charles s.Melching Department of Civil Construction and Environmental EngineeringMarquette University

The hypothesis that downstream moving storms with storm length less than watershed length（L;/L< 1.0） magnify the peak discharges as indicated by kinematic-wave models in previous studies was evaluated in an analysis... 详细信息

The hypothesis that downstream moving storms with storm length less than watershed length（L;/Lscharges as indicated by kinematic-wave models in previous studies was evaluated in an analysis of the dimensionless peak discharge and dimensionless storm *** unpublished experimental data collected for a V-shaped watershed in the Watershed Experimentation system（WEs） at the University of Illinois at Urbana-Champaign,were used in comparison with the simulation results of a kinematic-wave *** is found that downstream moving storms with L;/L se the peak discharges to a limited extent compared to stationary storms,and the kinematic-wave model overstates the increase in the peak flows resulting from downstream moving storms with L;/L s in the experimental watershed,the accuracy of kinematic-wave and dynamic-wave models for the simulation of surface runoff resulting from upstream and downstream moving storms was evaluated utilizing the same experimental *** kinematic-wave model simulates the upstream moving storms pretty well,***-sutcliffe coefficient of model fit efficiency equal to 0.948 and 0.831 for storms lengths equal to and not equal to the watershed length,***,the kinematic wave model substantially overestimates the peak discharge of downstream moving storms,and yields generally poorer fits than for upstream moving storm,*** equal to 0.867 and 0.674 for storms with lengths equal to and not equal to the watershed length,*** dynamic-wave model simulates the downstream moving storms pretty well,*** equal to 0.843 and 0.879 for storms with lengths equal to and not equal to the watershed length,respectively,indicating backwater significantly affects runoff for even this simple experimental *** that storm movement did not substantially magnify peak discharge,the assumption of stationary storms made

关键词： Moving storms Kinematic-wave Dynamic-wave Experimental data Dimensional analysis

Afforestation,restoration and regeneration——Not all trees are created equal

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Journal of Forestry Research 2014年第1期25卷 3-20页

作者： shaneka s.Lawson charles H.Michler UsDA Forest service Northern Research StationHardwood Tree Improvement and Regeneration Center (HTIRC)Purdue UniversityDepartment of Forestry and Natural Resources

Undulations in weather patterns have caused climate shifts of increased frequency and duration around the world. The need for additional research and model data on this pressing problem has resulted in a plethora of research groups examining a particular tree species or biome for negative effects of climate change. This review aims to （1） collect and merge recent research data on regeneration within old- and new-growth forests, （2） highlight and expand upon selected topics for additional discussion, and （3） report how shade tolerance, drought toler- ance, and inherent plasticity affect tree growth and development. Al- though shade and drought tolerance have been well studied by a number of research groups, this review reveals that in-depth analysis of a single or a few species in a given area will not generate the data required to implement a successful regeneration plan. studies using historical accounts of previous species composition, information regarding site sea- sonality, species competition, and individual responses to drought and shade are needed to （1） develop best management plans and （2） ensure future modeling experiments are focused on a greater variety of species using more innovative methods to evaluate climate change effects.

关键词： Climate change shade tolerance drought tolerance canopy gaps invasive species

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Less common neoplasms of the pancreas

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World Journal of Gastroenterology 2006年第20期12卷 3180-3185页

作者： Abby L Mulkeen Peter s Yoo charles Cha Department of surgery Yale University school of Medicine New HavenCT and the VACT Healthcare SystemWest HavenCT330 Cedar StreetLH 118PO Box 208062New HavenCT06520-8062United States

Recently, there has been an increased recognition of neoplasms of the pancreas other than ductal adenocarcinorna. Although not as well studied or characterized as pancreatic adenocarcinorna there are many distinct lesions which exhibit diverse biological behaviors and varying degrees of malignancy. These lesions include： endocrine neoplasms, cystic tumors, solid pseudopapillary tumors, acinar cell carcinoma, squamous cell carcinoma, primary lymphoma of the pancreas, and metastatic lesions to the pancreas. These less common neoplasms are being diagnosed more frequently as the number and sensitivity of diagnostic imaging studies increase. This review article discusses the clinical course, diagnosis, and treatment of these less common, but quite relevant, neoplasms of the pancreas.

关键词： Pancreas Neoplasms Ductal adenocarcinoma