The impact of MRI steady-state sequences as an additional assessment modality in vestibular schwannoma patients after LINAC stereotactic radiotherapy or radiosurgery

The present work focuses on the in-silico investigation of the steady-state blood flow in straight microtubes, incorporating advanced constitutive modeling for human blood and blood plasma. The blood constitutive model accounts for the interplay between thixotropy and elasto-visco-plasticity via a scalar variable that describes the level of the local blood structure at any instance. The constitutive model is enhanced by the non-Newtonian modeling of the plasma phase, which features bulk viscoelasticity. Incorporating microcirculation phenomena such as the cell-free layer (CFL) formation or the Fåhraeus and the Fåhraeus-Lindqvist effects is an indispensable part of the blood flow investigation. The coupling between them and the momentum balance is achieved through correlations based on experimental observations. Notably, we propose a new simplified form for the dependence of the apparent viscosity on the hematocrit that predicts the CFL thickness correctly. Our investigation focuses on the impact of the microtube diameter and the pressure-gradient on velocity profiles, normal and shear viscoelastic stresses, and thixotropic properties. We demonstrate the microstructural configuration of blood in steady-state conditions, revealing that blood is highly aggregated in narrow tubes, promoting a flat velocity profile. Additionally, the proper accounting of the CFL thickness shows that for narrow microtubes, the reduction of discharged hematocrit is significant, which in some cases is up to 70%. At high pressure-gradients, the plasmatic proteins in both regions are extended in the flow direction, developing large axial normal stresses, which are more significant in the core region. We also provide normal stress predictions at both the blood/plasma interface (INS) and the tube wall (WNS), which are difficult to measure experimentally. Both decrease with the tube radius; however, they exhibit significant differences in magnitude and type of variation. INS varies linearly from 4.5 to 2 Pa, while WNS exhibits an exponential decrease taking values from 50 mPa to zero.

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Malignancy in vestibular schwannoma after stereotactic radiotherapy: A case report and review of the literature

The Laryngoscope ◽

10.1002/lary.21448 ◽

2011 ◽

Vol 121 (5) ◽

pp. 923-928 ◽

Cited By ~ 40

Author(s):

Sami Tanbouzi Husseini ◽

Enrico Piccirillo ◽

Abdelkader Taibah ◽

Carlo T. Paties ◽

Roberto Rizzoli ◽

...

Keyword(s):

Case Report ◽

Vestibular Schwannoma ◽

Stereotactic Radiotherapy ◽

Review Of The Literature

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Does footwear type impact the number of steps required to reach gait steady state?: An innovative look at the impact of foot orthoses on gait initiation

Gait & Posture ◽

10.1016/j.gaitpost.2010.02.016 ◽

2010 ◽

Vol 32 (1) ◽

pp. 29-33 ◽

Cited By ~ 34

Author(s):

Bijan Najafi ◽

Daniel Miller ◽

Beth D. Jarrett ◽

James S. Wrobel

Keyword(s):

Steady State ◽

Gait Initiation ◽

Foot Orthoses ◽

The Impact

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Research on Cooperative Innovation Behavior of Industrial Cluster Based on Subject Adaptability

Discrete Dynamics in Nature and Society ◽

10.1155/2016/3069065 ◽

2016 ◽

Vol 2016 ◽

pp. 1-19 ◽

Cited By ~ 2

Author(s):

Xiaohui Jia ◽

Minghui Jiang ◽

Lei Shi

Keyword(s):

Steady State ◽

Evolutionary Game ◽

Industrial Cluster ◽

Industrial Clusters ◽

Government Support ◽

Correlated Equilibrium ◽

Game Model ◽

Cooperative Innovation ◽

The Cost ◽

The Impact

From the perspective of the interactive cooperation among subjects, this paper portrays the process of cooperative innovation in industrial cluster, in order to capture the correlated equilibrium relationship among them. Through the utilization of two key tools, evolutionary stable strategy and replicator dynamics equations, this paper considers the cost and gains of cooperative innovation and the amount of government support as well as other factors to build and analyze a classic evolutionary game model. On this basis, the subject’s own adaptability is introduced, which is regarded as the system noise in the stochastic evolutionary game model so as to analyze the impact of adaptability on the game strategy selection. The results show that, in the first place, without considering subjects’ adaptability, their cooperation in industrial clusters depends on the cost and gains of innovative cooperation, the amount of government support, and some conditions that can promote cooperation, namely, game steady state. In the second place after the introduction of subjects’ adaptability, it will affect both game theory selection process and time, which means that the process becomes more complex, presents the nonlinear characteristics, and helps them to make faster decisions in their favor, but the final steady state remains unchanged.

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Life Prediction of Power Turbine Components for High Exhaust Back Pressure Applications: Part I — Disks

Volume 7A: Structures and Dynamics ◽

10.1115/gt2015-43333 ◽

2015 ◽

Author(s):

Dipankar Dua ◽

Brahmaji Vasantharao

Keyword(s):

Steady State ◽

Secondary Flow ◽

Gas Turbines ◽

Life Prediction ◽

Creep Damage ◽

Back Pressure ◽

System Level ◽

Cyclic Life ◽

Power Turbine ◽

The Impact

Industrial and aeroderivative gas turbines when used in CHP and CCPP applications typically experience an increased exhaust back pressure due to pressure losses from the downstream balance-of-plant systems. This increased back pressure on the power turbine results not only in decreased thermodynamic performance but also changes power turbine secondary flow characteristics thus impacting lives of rotating and stationary components of the power turbine. This Paper discusses the Impact to Fatigue and Creep life of free power turbine disks subjected to high back pressure applications using Siemens Energy approach. Steady State and Transient stress fields have been calculated using finite element method. New Lifing Correlation [1] Criteria has been used to estimate Predicted Safe Cyclic Life (PSCL) of the disks. Walker Strain Initiation model [1] is utilized to predict cycles to crack initiation and a fracture mechanics based approach is used to estimate propagation life. Hyperbolic Tangent Model [2] has been used to estimate creep damage of the disks. Steady state and transient temperature fields in the disks are highly dependent on the secondary air flows and cavity dynamics thus directly impacting the Predicted Safe Cyclic Life and Overall Creep Damage. A System-level power turbine secondary flow analyses was carried out with and without high back pressure. In addition, numerical simulations were performed to understand the cavity flow dynamics. These results have been used to perform a sensitivity study on disk temperature distribution and understand the impact of various back pressure levels on turbine disk lives. The Steady Sate and Transient Thermal predictions were validated using full-scale engine test and have been found to correlate well with the test results. The Life Prediction Study shows that the impact on PSCL and Overall Creep damage for high back pressure applications meets the product design standards.

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Driving forces and structural changes of China as a market provider for Korea

Journal of Korea Trade ◽

10.1108/jkt-03-2018-0014 ◽

2018 ◽

Vol 22 (3) ◽

pp. 194-211 ◽

Cited By ~ 1

Author(s):

Yongqi Feng ◽

Tianshu Zhang

Keyword(s):

Steady State ◽

Driving Force ◽

Design Methodology ◽

Structural Changes ◽

Driving Forces ◽

Consumption Expenditure ◽

Input Output ◽

Content Type ◽

Fixed Capital Formation ◽

The Impact

Purpose The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.

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EGR cylinder deactivation strategy to accelerate the warm-up and restart processes in a Diesel engine operating at cold conditions

International Journal of Engine Research ◽

10.1177/14680874211039587 ◽

2021 ◽

pp. 146808742110395

Author(s):

José Galindo ◽

Vicente Dolz ◽

Javier Monsalve-Serrano ◽

Miguel Angel Bernal Maldonado ◽

Laurent Odillard

Keyword(s):

Steady State ◽

Diesel Engine ◽

Internal Combustion Engines ◽

Cold Start ◽

Pollutant Emissions ◽

Oxidation Catalyst ◽

Maximum Efficiency ◽

Warm Up ◽

Cylinder Deactivation ◽

The Impact

The aftertreatment systems used in internal combustion engines need high temperatures for reaching its maximum efficiency. By this reason, during the engine cold start period or engine restart operation, excessive pollutant emissions levels are emitted to the atmosphere. This paper evaluates the impact of using a new cylinder deactivation strategy on a Euro 6 turbocharged diesel engine running under cold conditions (−7°C) with the aim of improving the engine warm-up process. This strategy is evaluated in two parts. First, an experimental study is performed at 20°C to analyze the effect of the cylinder deactivation strategy at steady-state and during an engine cold start at 1500 rpm and constant load. In particular, the pumping losses, pollutant emissions levels and engine thermal efficiency are analyzed. In the second part, the engine behavior is analyzed at steady-state and transient conditions under very low ambient temperatures (−7°C). In these conditions, the results show an increase of the exhaust temperatures of around 100°C, which allows to reduce the diesel oxidation catalyst light-off by 250 s besides of reducing the engine warm-up process in approximately 120 s. This allows to reduce the CO and HC emissions by 70% and 50%, respectively, at the end of the test.

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The influx rate of long-period comets in the Earth's neighborhood and their debris contribution to the interplanetary medium

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314005006 ◽

2012 ◽

Vol 10 (H16) ◽

pp. 140-140

Author(s):

Julio Angel Fernández

Keyword(s):

Steady State ◽

Interplanetary Medium ◽

Interplanetary Dust ◽

Large Contribution ◽

Influx Rate ◽

Long Period ◽

Impact Rate ◽

Total Magnitude ◽

Dust Complex ◽

The Impact

AbstractWe analyze the flux of new and evolved long-period comets (LPCs) reaching the Earth's neighborhood (perihelion distances q < 1.3 AU), their physical lifetimes, and their implications as regards to the amount of meteoritic matter that is being deposited in the near-Earth region. The flux of LPCs with q < 1.3 au is found to be of about 340 ± 40, brighter than absolute total magnitude 8.6 (radius R ~ 0.6 km) (Fernández and Sosa 2012). Bearing in mind that most of these comets disintegrate into meteoritic matter, this represents a large contribution to the interplanetary dust complex which requires an amount of matter of about 10 tons s−1 to keep it in steady state. These aspects, as well as the impact rate with Earth of meteoroids of LPC origin, will be discussed in this presentation.

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