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Iowa State University

2010

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Opinion Formation On Adaptive Networks With Intensive Average Degree, Beate Schmittmann, Abhishek Mukhopadhyay Dec 2010

Opinion Formation On Adaptive Networks With Intensive Average Degree, Beate Schmittmann, Abhishek Mukhopadhyay

Beate Schmittmann

We study the evolution of binary opinions on a simple adaptive network of N nodes. At each time step, a randomly selected node updates its state (“opinion”) according to the majority opinion of the nodes that it is linked to; subsequently, all links are reassigned with probability p̃ (q̃ ) if they connect nodes with equal (opposite) opinions. In contrast to earlier work, we ensure that the average connectivity (“degree”) of each node is independent of the system size (“intensive”), by choosing p̃ and q̃ to be of O(1/N). Using simulations and analytic arguments, we determine the final steady states …

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Utilization Of Diets Containing Graded Levels Of Ethanol Production Co-Products By Nile Tilapia, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan Dec 2010

Utilization Of Diets Containing Graded Levels Of Ethanol Production Co-Products By Nile Tilapia, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan

Kurt A. Rosentrater

A feeding trial was performed to investigate inclusion levels of distillers dried grains with solubles (DDGS) as a fishmeal replacement for juvenile Nile tilapia (Oreochromis niloticus). On a dry matter basis, five isocaloric [19.3 ± 0.4 kJ/g (mean ± SE)], isonitrogenous (39.1 ± 0.5% crude protein) diets were formulated to contain 17.5%, 20%, 22.5%, 25%, and 27.5% DDGS and compared against a 0% DDGS, reference diet (gross energy = 14.5 kJ/g; crude protein = 39.8%). The reference diet resulted in significantly higher body weight gain (BWG), food conversion ratio (FCR), and protein efficiency ratio (PER) than experimental diets except that …

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Molecular Dynamics Simulation Of Fractal Aggregate Diffusion, Gaurav Pranami, Monica H. Lamm, R. Dennis Vigil Nov 2010

Molecular Dynamics Simulation Of Fractal Aggregate Diffusion, Gaurav Pranami, Monica H. Lamm, R. Dennis Vigil

R. Dennis Vigil

The diffusion of fractal aggregates constructed with the method by Thouy and Jullien [J. Phys. A 27, 2953 (1994)] comprised of Np spherical primary particles was studied as a function of the aggregate mass and fractal dimension using molecular dynamics simulations. It is shown that finite-size effects have a strong impact on the apparent value of the diffusion coefficient (D), but these can be corrected by carrying out simulations using different simulation box sizes. Specifically, the diffusion coefficient is inversely proportional to the length of a cubic simulation box, and the constant of proportionality appears to be independent of …

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Attribution Of Spatial And Temporal Variations In Terrestrial Methane Flux Over North America, X. F. Xu, Hanqin Tian, C. Zhang, M. L. Liu, Wei Ren, G. S. Chen, Chaoqun (Crystal) Lu, L. Bruhwiler Nov 2010

Attribution Of Spatial And Temporal Variations In Terrestrial Methane Flux Over North America, X. F. Xu, Hanqin Tian, C. Zhang, M. L. Liu, Wei Ren, G. S. Chen, Chaoqun (Crystal) Lu, L. Bruhwiler

Chaoqun (Crystal) Lu

The attribution of spatial and temporal variations in terrestrial methane (CH4) flux is essential for assessing and mitigating CH4 emission from terrestrial ecosystems. In this study, we used a process-based model, the Dynamic Land Ecosystem Model (DLEM), in conjunction with spatial data of six major environmental factors to attribute the spatial and temporal variations in the terrestrial methane (CH4) flux over North America from 1979 to 2008 to six individual driving factors and their interaction. Over the past three decades, our simulations indicate that global change factors accumulatively contributed 23.51 ± 9.61 T g CH4-C (1 Tg = 1012 g) …

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Dryland Soil Carbon And Nitrogen Influenced By Sheep Grazing In The Wheat–Fallow System, Upendra M. Sainju, Andrew W. Lenssen, Hayes B. Goosey, Erin Snyder, Patrick G. Hatfield Nov 2010

Dryland Soil Carbon And Nitrogen Influenced By Sheep Grazing In The Wheat–Fallow System, Upendra M. Sainju, Andrew W. Lenssen, Hayes B. Goosey, Erin Snyder, Patrick G. Hatfield

Andrew W. Lenssen

Sheep (Ovis aries) grazing during fallow for weed control in wheat (Triticum aestivum L.)–fallow systems may influence soil C and N levels and grain yields by returning part of consumed crop residue to the soil through feces and urine. We evaluated the effects of fallow management (sheep grazing [grazing], herbicide application [chemical], and tillage [mechanical]) for weed control and soil water conservation and cropping sequence (continuous spring wheat [CSW], spring wheat–fallow [SW-F], and winter wheat–fallow [WW-F]) on soil organic carbon (SOC), inorganic carbon (SIC), total nitrogen (STN), NH4–N, and NO3–N levels at the 0- to 120-cm depth and wheat yield. …

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Granular Packing Influences Bulk Density Of Ddgs, Christine Keierleber, Kurt A. Rosentrater Nov 2010

Granular Packing Influences Bulk Density Of Ddgs, Christine Keierleber, Kurt A. Rosentrater

Kurt A. Rosentrater

As the quantity of ethanol produced continues to increase, the amount of distillers dried grains with solubles (DDGS), the primary coproduct of ethanol manufacturing, has become more widely available. Currently, the main consumer of DDGS is the livestock industry, but new value-added uses are garnering interest. With the increase in the availability of, and demand for DDGS, transportation has become an important issue because DDGS must be shipped increasingly long distances using railways. Rail transportation is expensive, especially considering the quantities of DDGS that can be loaded onto unit trains. DDGS often has low bulk density and poor flowability characteristics. …

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Do Surfaces With Mixed Hydrophilic And Hydrophobic Areas Enhance Pool Boiling?, Amy Rachel Betz, Jie Xu, Huihe Qiu, Daniel Attinger Oct 2010

Do Surfaces With Mixed Hydrophilic And Hydrophobic Areas Enhance Pool Boiling?, Amy Rachel Betz, Jie Xu, Huihe Qiu, Daniel Attinger

Daniel Attinger

We demonstrate that smooth and flat surfaces combining hydrophilic and hydrophobicpatterns improve pool boiling performance. Compared to a hydrophilicsurface with 7° wetting angle, the measured critical heat flux and heat transfer coefficients of the enhanced surfaces are, up to respectively, 65% and 100% higher. Different networks combining hydrophilic and hydrophobic regions are characterized. While all tested networks enhance the heat transfer coefficient, large enhancements of critical heat flux are typically found for hydrophilic networks featuring hydrophobic islands. Hydrophilic networks indeed are shown to prevent the formation of an insulating vapor layer.

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Regional Assemblages Of Lygus (Heteroptera: Miridae) In Montana Canola Fields, Sue Blodgett, R. A. Ritter, A. W. Lenssen, M. L. Taper Oct 2010

Regional Assemblages Of Lygus (Heteroptera: Miridae) In Montana Canola Fields, Sue Blodgett, R. A. Ritter, A. W. Lenssen, M. L. Taper

Sue Blodgett

Sweep net sampling of canola (Brassica napus L.) was conducted in 2002 and 2003 to determine Lygus (Heteroptera: Miridae) species composition and parasitism levels in four regions of Montana. Regardless of region or seasonal change, Lygus elisus (Van Duzee) was the dominant species in all canola fields sampled, averaging 60–99% of the total adult populations. Lygus borealis (Kelton), Lygus keltoni (Schwartz) and Lygus lineolaris (Palisot) were detected at much lower levels. Total lygus population density was greatest in the southwest and central regions. The northeast and southwest regions had the greatest lygus species diversity. The proportion of L. elisus increased …

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Immunocontraception In Wild Horses (Equus Caballus) Extends Reproductive Cycling Beyond The Normal Breeding Season, Cassandra M.V. Nuñez, James S. Adelman, Daniel I. Rubenstein Oct 2010

Immunocontraception In Wild Horses (Equus Caballus) Extends Reproductive Cycling Beyond The Normal Breeding Season, Cassandra M.V. Nuñez, James S. Adelman, Daniel I. Rubenstein

Cassandra M.V. Nuñez

Although the physiological effects of immunocontraceptive treatment with porcine zona pellucida (PZP) have been well studied, little is known about PZP's effects on the scheduling of reproductive cycling. Recent behavioral research has suggested that recipients of PZP extend the receptive breeding period into what is normally the non-breeding season. To determine if this is the case, we compiled foaling data from wild horses (Equus caballus) living on Shackleford Banks, North Carolina for 4 years pre- and 8 years post-contraception management with PZP (pre-contraception, n = 65 births from 45 mares; post-contraception, n = 97 births from 46 mares). Gestation lasts …

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Self-Organizing Inputs For Adaptive Neurocontrol Of Large-Scale Systems, Simon Laflamme, Jerome J. Connor Oct 2010

Self-Organizing Inputs For Adaptive Neurocontrol Of Large-Scale Systems, Simon Laflamme, Jerome J. Connor

Simon Laflamme

Black-box modeling for system identification and control can be constrained by the geometric scale of a plant. Those constrains arise from a technical or economical issue in obtaining input-output data sets for training purposes. A solution is sequential adaptation, which must be achieved in real time in the case of control systems, because a prescribed level of performance is required while external excitations are occurring. A major challenge is the proper selection of inputs that would lead to a quick and optimal adaptation. This paper proposes a new method for selection of inputs in black-box modeling. The method, termed the …

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The Rhetoric Of Architecture And Memory Of The Holy Sepulchre In Byzantium, Jelena Bogdanović Oct 2010

The Rhetoric Of Architecture And Memory Of The Holy Sepulchre In Byzantium, Jelena Bogdanović

Jelena Bogdanović

The actual physical appearance of the Anastasis‐Golgotha complex in Jerusalem during Byzantine times is not documented archaeologically. The extent and significance of the Byzantine interventions between the seventh and eleventh centuries, after the destructions by the Persians, from earthquakes, and devastating fire set by the Caliph al‐Hākim in 1009, remain understudied. Presumably, after each destruction the first structure restored for veneration was the major locus sanctus, the Holy Sepulchre. Because it is doubtful that the Byzantines kept records on the architectural design of the Holy Sepulchre, their reconstructions were not based on a definite pictorial scheme, but rather on the …

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Use Of A Porous Membrane For Gas Bubble Removal In Microfluidic Channels: Physical Mechanisms And Design Criteria, Jie Xu, Regis Vaillant, Daniel Attinger Oct 2010

Use Of A Porous Membrane For Gas Bubble Removal In Microfluidic Channels: Physical Mechanisms And Design Criteria, Jie Xu, Regis Vaillant, Daniel Attinger

Daniel Attinger

We demonstrate and explain a simple and efficient way to remove gas bubbles from liquid-filled microchannels, by integrating a hydrophobic porous membrane on top of the microchannel. A prototype chip is manufactured in hard, transparent polymer with the ability to completely filter gas plugs out of a segmented flow at rates up to 7.4 μl/s/mm2 of membrane area. The device involves a bubble generation section and a gas removal section. In the bubble generation section, a T-junction is used to generate a train of gas plugs into a water stream. These gas plugs are then transported toward the gas removal …

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Artificial Neural Network Modeling Of Ddgs Flowability With Varying Process And Storage Parameters, Rumela Bhadra, K. Muthukumarappan, Kurt A. Rosentrater Oct 2010

Artificial Neural Network Modeling Of Ddgs Flowability With Varying Process And Storage Parameters, Rumela Bhadra, K. Muthukumarappan, Kurt A. Rosentrater

Kurt A. Rosentrater

Neural Network (NN) modeling techniques were used to predict flowability behavior in distillers dried grains with solubles (DDGS) prepared with varying CDS (10, 15, and 20%, wb), drying temperature (100, 200, and 300°C), cooling temperature (-12, 0, and 35°C) and cooling time (0 and 1 month) levels. Response variables were selected based on our previous research results, and included aerated bulk density, Hausner Ratio, Angle of Repose, Total Flowability Index, and Jenike Flow Function. Various neural network models were developed using multiple input variables in order to predict single response variables or multiple response variables simultaneously. The NN models were …

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Tilapia: Profile And Economic Importance, Kamal Mjoun, Kurt A. Rosentrater, Michael L. Brown Oct 2010

Tilapia: Profile And Economic Importance, Kamal Mjoun, Kurt A. Rosentrater, Michael L. Brown

Kurt A. Rosentrater

Tilapia is the common name broadly applied to a group of cichlid fishes native to Africa, the Mediterranean, and the Middle East. Tilapia are some of the oldest cultured fishes, as depicted in line drawings found in Egyptian tombs that date back to 2000 BC. This group consists of three economically important genera, which are taxonomically distinguished according to their reproductive behaviors: Tilapia, Oreochromis, and Sarotherodon, all are commonly known as “tilapia.” Tilapia are biparental caring-substrate spawners; Oreochromis are generally maternal mouth brooders; and Sarotherodon are generally paternal or biparental mouth brooders. Currently, Nile tilapia (Oreochromis niloticus; fig. 1) and …

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Tilapia: Environmental Biology And Nutritional Requirements, Kamal Mjoun, Kurt A. Rosentrater, Michael L. Brown Oct 2010

Tilapia: Environmental Biology And Nutritional Requirements, Kamal Mjoun, Kurt A. Rosentrater, Michael L. Brown

Kurt A. Rosentrater

Tilapia is one of the most widely cultured fish in the world. Currently, farmed tilapia represents more than 75% of world tilapia production (FAO, 2009), and this contribution has been exponentially growing in recent years. Several factors have contributed to the rapid global growth of tilapia. Tilapia are easily cultured and highly adaptable to a wide range of environmental conditions. Tilapia feed on a wide variety of dietary sources, including phytoplankton, periphyton, zooplanktons, larval fish, and detritus. Adult tilapia are principally herbivorous but readily adapt to complete commercial diets based on plant and animal protein sources. In the United States, …

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Can Segmented Flow Enhance Heat Transfer In Microchannel Heat Sinks?, Amy Rachel Betz, Daniel Attinger Sep 2010

Can Segmented Flow Enhance Heat Transfer In Microchannel Heat Sinks?, Amy Rachel Betz, Daniel Attinger

Daniel Attinger

Liquid cooling is an efficient way to remove heat fluxes with magnitudes up to 10,000 W/cm2. One limitation of current single-phase microchannel heat sinks is the relatively low Nusselt number, due to laminar flow. In this work, we experimentally investigate how to enhance the Nusselt number with the introduction of segmented flow. The segmented flow pattern was created by the periodic injection of air bubbles through a T-junction into water-filled channels. We designed a polycarbonate heat sink consisting of an array of seven parallel microchannels each with a square cross-section 500 μm wide. We show that segmented flow increases the …

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Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe Sep 2010

Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe

Kevin J. Roe

The winged mapleleaf, Quadrula fragosa, historically occurred in the Mississippi, Tennessee, Ohio, and Cumberland river drainages, but has suffered severe population and range reductions. At the time that the species was federally listed as endangered, its range was thought to have been reduced to a stretch of the St. Croix River between northwestern Wisconsin and east-central Minnesota. Recently, morphologically “Q. fragosa-like” specimens were discovered at sites in Arkansas (Ouachita River and Saline River), Missouri (Bourbeuse River), and Oklahoma (Little River). Subsequently, a plan was proposed to re-introduce Q. fragosa into portions of its historic range where its been extirpated from …

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Spatial And Temporal Patterns Of Ch4 And N2o Fluxes In Terrestrial Ecosystems Of North America During 1979–2008: Application Of A Global Biogeochemistry Model, Hanqin Tian, X. Xu, M. Liu, Wei Ren, C. Zhang, G. Chen, Chaoqun (Crystal) Lu Sep 2010

Spatial And Temporal Patterns Of Ch4 And N2o Fluxes In Terrestrial Ecosystems Of North America During 1979–2008: Application Of A Global Biogeochemistry Model, Hanqin Tian, X. Xu, M. Liu, Wei Ren, C. Zhang, G. Chen, Chaoqun (Crystal) Lu

Chaoqun (Crystal) Lu

Continental-scale estimations of terrestrial methane (CH4) and nitrous oxide (N2O) fluxes over a long time period are crucial to accurately assess the global balance of greenhouse gases and enhance our understanding and prediction of global climate change and terrestrial ecosystem feedbacks. Using a process-based global biogeochemical model, the Dynamic Land Ecosystem Model (DLEM), we quantified simultaneously CH4 and N2O fluxes in North America's terrestrial ecosystems from 1979 to 2008. During the past 30 years, approximately 14.69 ± 1.64 T g C a−1 (1 T g = 1012 g) of CH4, and 1.94 ± 0.1 T g N a−1 of N2O …

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Mechanistically Driven Development Of Iridium Catalysts For Asymmetric Allylic Substitution, John F. Hartwig, Levi M. Stanley Sep 2010

Mechanistically Driven Development Of Iridium Catalysts For Asymmetric Allylic Substitution, John F. Hartwig, Levi M. Stanley

Levi M. Stanley

Enantioselective allylic substitution reactions comprise some of the most versatile methods for preparing enantiomerically enriched materials. These reactions form products that contain multiple functionalities by creating carbon−nitrogen, carbon−oxygen, carbon−carbon, and carbon−sulfur bonds. For many years, the development of catalysts for allylic substitution focused on palladium complexes. However, studies of complexes of other metals have revealed selectivities that often complement those of palladium systems. Most striking is the observation that reactions with unsymmetrical allylic electrophiles that typically occur with palladium catalysts at the less hindered site of an allylic electrophile occur at the more hindered site with catalysts based on other …

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Bipolar Electrodes: A Useful Tool For Concentration, Separation, And Detection Of Analytes In Microelectrochemical Systems, François Mavré, Robbyn K. Anand, Derek R. Laws, Kwok-Fan Show, Byoung-Yong Chang, John A. Crooks, Richard M. Crooks Sep 2010

Bipolar Electrodes: A Useful Tool For Concentration, Separation, And Detection Of Analytes In Microelectrochemical Systems, François Mavré, Robbyn K. Anand, Derek R. Laws, Kwok-Fan Show, Byoung-Yong Chang, John A. Crooks, Richard M. Crooks

Robbyn Anand

Over the past decade, bipolar electrochemistry has emerged from relative obscurity to provide a promising new means for integrating electrochemistry into lab-on-a-chip systems. This article describes the fundamental operating principles of bipolar electrodes, as well as several interesting applications. The graphic, by François Mavré, shows the principle of operation of a bipolar electrode within a microfluidic channel overlaid on a background image of electrogenerated chemiluminescence from an array of 1000 bipolar electrodes.

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Hybrid Rationale For Shared Understanding, David Mott, Cheryl Giammanco, Michael C. Dorneich, Dave Braines Sep 2010

Hybrid Rationale For Shared Understanding, David Mott, Cheryl Giammanco, Michael C. Dorneich, Dave Braines

Michael C. Dorneich

Understanding the reasoning of others is a key aspect to achieving a shared understanding when collaboratively solving a problem, such as the generation of a plan, and recent observations of military planners suggest that it plays a key role in the planning process. An example of rationale is described where a misunderstanding is only resolved by the joint exploration and cross-challenging of the rationale. A prototype tool is described that permits the creation and visualization of the basic rationale via the use of Controlled English (CE). Using the example, the paper explores mechanisms that could potentially make more effective use …

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Making Plans Alive, Jitu Pater, Michael C. Dorneich, David Mott, Ali Bahrami, Cheryl Giammanco Sep 2010

Making Plans Alive, Jitu Pater, Michael C. Dorneich, David Mott, Ali Bahrami, Cheryl Giammanco

Michael C. Dorneich

Over the years, researchers have expended considerable effort in attempts to improve military planning, most notably via the provision of automated planning support tools. While there have been some successes (e.g. the DART system which was used for movement planning during Gulf war), planning still remains a very human‐orientated activity with little technical support. Why? A possible reason for this predicament is that researchers have not fully conceptualized the problem that planners face. For instance, a common approach has been to consider planning as a single process or a homogenous set of problems to be solved. Unfortunately, military planning is …

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A Conceptual Framework To Support A Multi-Level Planning Capability, Jitu Patel, Michael C. Dorneich, David Mott, Ali Bahrami, Cheryl Giammanco Sep 2010

A Conceptual Framework To Support A Multi-Level Planning Capability, Jitu Patel, Michael C. Dorneich, David Mott, Ali Bahrami, Cheryl Giammanco

Michael C. Dorneich

Over the years, military planning has attracted a lot of attention by researchers with the aim of providing automated planning support tools. There have been some successes (e.g., DART system which was used for movement during Gulf war) however, to-date, planning still remains a very human activity with little or no automated support tools. Why? A possible reason for this predicament is that researchers have not fully conceptualized the problem. For instance, a common approach has been to consider planning as a single process or a homogenous set of problems to be solved. Unfortunately, military planning is not a single …

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Interfacial Temperature Measurements, High-Speed Visualization And Finite-Element Simulations Of Droplet Impact And Evaporation On A Solid Surface, Rajneesh Bhardwaj, Jon P. Longtin, Daniel Attinger Sep 2010

Interfacial Temperature Measurements, High-Speed Visualization And Finite-Element Simulations Of Droplet Impact And Evaporation On A Solid Surface, Rajneesh Bhardwaj, Jon P. Longtin, Daniel Attinger

Daniel Attinger

The objective of this work is to investigate the coupling of fluid dynamics, heat transfer and mass transfer during the impact and evaporation of droplets on a heated solid substrate. A laser-based thermoreflectance method is used to measure the temperature at the solid–liquid interface, with a time and space resolution of 100 μs and 20 μm, respectively. Isopropanol droplets with micro- and nanoliter volumes are considered. A finite-element model is used to simulate the transient fluid dynamics and heat transfer during the droplet deposition process, considering the dynamics of wetting as well as Laplace and Marangoni stresses on the liquid–gas …

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Tbioptions Postcard, Debra M. Sellers Sep 2010

Tbioptions Postcard, Debra M. Sellers

Debra M. Sellers

TBIoptions helps people with traumatic brain injury (TBI), their families and caregivers. It links people to services and resources in their local communities to promote successful living.

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Tbioptions Brochure, Debra M. Sellers Sep 2010

Tbioptions Brochure, Debra M. Sellers

Debra M. Sellers

TBIoptions helps survivors of traumatic brain injury and their families contact organizations in Kansas to promote successful living. Examples include therapy, personal care attendants, housing, transportation, legal, mental health, and vocational services.

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Physical And Chemical Characterization Of Fuel Ethanol Coproducts Relevant To Value-Added Uses, Rumela Bhadra, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan Sep 2010

Physical And Chemical Characterization Of Fuel Ethanol Coproducts Relevant To Value-Added Uses, Rumela Bhadra, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan

Kurt A. Rosentrater

One of the fastest growing industries in the United States is the fuel ethanol industry. In terms of ethanol production capability, the industry has grown by more than 600% since the year 2000. The major coproducts from corn-based ethanol include distillers dried grains with solubles (DDGS) and carbon dioxide. DDGS is used as a livestock feed because it contains high quantities of protein, fiber, amino acids, and other nutrients. The goal of this study was to quantify various chemical and physical properties of DDGS, distillers wet grains (DWG), and distillers dried grain (DDG) from several plants in South Dakota. Chemical …

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A Generalized Finite Element Formulation For Arbitrary Basis Functions: From Isogeometric Analysis To Xfem, D. J. Benson, Y. Bazilevs, E. Deluycker, Ming-Chen Hsu, M. Scott, T. J. R. Hughes, T. Belytschko Aug 2010

A Generalized Finite Element Formulation For Arbitrary Basis Functions: From Isogeometric Analysis To Xfem, D. J. Benson, Y. Bazilevs, E. Deluycker, Ming-Chen Hsu, M. Scott, T. J. R. Hughes, T. Belytschko

Ming-Chen Hsu

Many of the formulations of current research interest, including iosogeometric methods and the extended finite element method, use nontraditional basis functions. Some, such as subdivision surfaces, may not have convenient analytical representations. The concept of an element, if appropriate at all, no longer coincides with the traditional definition. Developing a new software for each new class of basis functions is a large research burden, especially, if the problems involve large deformations, non-linear materials, and contact. The objective of this paper is to present a method that separates as much as possible the generation and evaluation of the basis functions from …

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Computational Vascular Fluid–Structure Interaction: Methodology And Application To Cerebral Aneurysms, Y. Bazilevs, Ming-Chen Hsu, Y. Zhang, Z. Wang, T. Kvamsdal, S. Hentschel, J. G. Isaksen Aug 2010

Computational Vascular Fluid–Structure Interaction: Methodology And Application To Cerebral Aneurysms, Y. Bazilevs, Ming-Chen Hsu, Y. Zhang, Z. Wang, T. Kvamsdal, S. Hentschel, J. G. Isaksen

Ming-Chen Hsu

A computational vascular fluid–structure interaction framework for the simulation of patient-specific cerebral aneurysm configurations is presented. A new approach for the computation of the blood vessel tissue prestress is also described. Simulations of four patient-specific models are carried out, and quantities of hemodynamic interest such as wall shear stress and wall tension are studied to examine the relevance of fluid–structure interaction modeling when compared to the rigid arterial wall assumption. We demonstrate that flexible wall modeling plays an important role in accurate prediction of patient-specific hemodynamics. Discussion of the clinical relevance of our methods and results is provided.

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全球变化与陆地系统综合集成模拟 ——新一代陆地生态系统动态模型 (Dlem), 汉勤 田, 明亮 刘, 弛 张, 巍 任, 小锋 徐, 广生 陈, 超群 吕, 波 陶 Aug 2010

全球变化与陆地系统综合集成模拟 ——新一代陆地生态系统动态模型 (Dlem), 汉勤 田, 明亮 刘, 弛 张, 巍 任, 小锋 徐, 广生 陈, 超群 吕, 波 陶

Chaoqun (Crystal) Lu

人类社会从陆地生态系统获取生产和生活资料的同时也作为一种干扰形式改变着地气之间的动态平衡。这三个既独立又相互耦合的子系统共同组成了一个复杂的陆地系统。如何深入理解这一系统的过程和机制是人类应对气候变化挑战的前提条件。陆地生态系统模型作为一种集成工具，已广泛应用于全球变化研究的各个领域，但从输入数据到模型结构和过程等诸多方面仍存在很大的不确定性。近年来，随着大气和地面生态观测网络的不断完善以及遥感等空间技术的不断强大，使陆地生态系统模型进一步发展和突破成为可能。新一代多因子驱动的陆地生态系统动态模型(Dynamic Land Ecosystem Model, DLEM) 正是在这一背景下 应运而生的。本文旨在介绍DLEM的主体框架、输入输出变量、关键过程、主要功能和特点。

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