Numerically simulated model of meteor body fragments distribution after destruction

A Ku-band wideband conformal array antenna with13×19elements is presented in the paper. The array has a spherical structure, and its element is a proximity-coupled stacked patches antenna with a cavity-backed ground plane. The stacked patches and the cavity produce multiple coupled resonances, which enhance the bandwidth of the element extremely. A simulated model with the reasonable dimensions is framed with the coupling analyses, and the effective simulated results and good computing efficiency are obtained simultaneously. The measured results of the center embedded element in the whole array show a bandwidth exceeding 40%VSWR<2, which is close to the simulated matching performance.

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Comparing an Approximate Queuing Approach with Simulation for the Solution of a Cross-Docking Problem

Journal of Applied Mathematics ◽

10.1155/2017/4987127 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Roberta Briesemeister ◽

Antônio G. N. Novaes

Keyword(s):

Queue Length ◽

Computational Analysis ◽

Queuing Model ◽

Simulated Model ◽

Final Destination ◽

Cross Docking ◽

Efficiency Performance ◽

Management Concept ◽

Intermediate Facilities ◽

To Receive

Cross-docking is a logistics management concept in which products are temporarily unloaded at intermediate facilities and loaded onto output trucks to be sent to their final destination. In this paper, we propose an approximate nonstationary queuing model to size the number of docks to receive the trucks, so that their unloading will be as short as possible at the receiving dock, thus making the cross-docking process more efficient. It is observed that the stochastic queuing process may not reach the steady equilibrium state. A type of modeling that does not depend on the stationary characteristics of the process developed is applied. In order to measure the efficiency, performance, and possible adjustments of the parameters of the algorithm, an alternative simulation model is proposed using the Arena® software. The simulation uses analytic tools to make the problem more detailed, which is not allowed in the theoretical model. The computational analysis compares the results of the simulated model with the ones obtained with the theoretical algorithm, considering the queue length and the average waiting time of the trucks. Based on the results obtained, the simulation represented very well the proposed problem and possible changes can be easily detected with small adjustments in the simulated model.

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The Effect of Catheter to Vein Ratio on Blood Flow Rates in a Simulated Model of Peripherally Inserted Central Venous Catheters

CHEST Journal ◽

10.1378/chest.10-2637 ◽

2011 ◽

Vol 140 (1) ◽

pp. 48-53 ◽

Cited By ~ 117

Author(s):

Thomas P. Nifong ◽

Timothy J. McDevitt

Keyword(s):

Blood Flow ◽

Central Venous Catheters ◽

Central Venous ◽

Flow Rates ◽

Simulated Model

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407 Oblique View versus Short Axis View in Ultrasonography-Guided Central Venous Catheterization: Incidence of Posterior Vessel Wall Puncture in a Simulated Model

Annals of Emergency Medicine ◽

10.1016/j.annemergmed.2012.06.439 ◽

2012 ◽

Vol 60 (4) ◽

pp. S143

Author(s):

K. Berona ◽

J. Wilson ◽

R. Wang

Keyword(s):

Vessel Wall ◽

Central Venous Catheterization ◽

Short Axis ◽

Short Axis View ◽

Central Venous ◽

Oblique View ◽

Simulated Model ◽

Venous Catheterization ◽

Axis View

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Effect of Ballistic Electrons on the Optical Response of Hyperbolic Metamaterials

Advanced Electromagnetics ◽

10.7716/aem.v8i5.1314 ◽

2019 ◽

Vol 8 (5) ◽

pp. 23-28

Author(s):

G. M. Marega ◽

E. Marega ◽

B.-H. V. Borges ◽

A. F. Da Mota

Keyword(s):

Experimental Study ◽

Optical Transmission ◽

Ballistic Transport ◽

Optical Response ◽

Analytic Approximation ◽

Metal Insulator ◽

Hyperbolic Metamaterials ◽

Hyperbolic Metamaterial ◽

Simulated Model ◽

Metal Insulator Metal

This paper presents a theoretical and experimental study of the effect of ballistic electrons on the optical response of MIM (Metal-Insulator-Metal) like hyperbolic metamaterial structures. The simulated model using standard parameters and the experimental optical transmission show a 20% peak difference due to the presence of ballistic transport in the metal. A semi-analytic approximation based on the Drude's model is used for accurately predicting the optical response of the hyperbolic substrate and plasmon damping in the fabricated metasurfaces.

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AGENT-BASED CROWD SIMULATION CONSIDERING EMOTION CONTAGION FOR EMERGENCY EVACUATION PROBLEM

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-1-w5-193-2015 ◽

2015 ◽

Vol XL-1-W5 ◽

pp. 193-196 ◽

Cited By ~ 16

Author(s):

H. Faroqi ◽

M.-S. Mesgari

Keyword(s):

Emergency Situation ◽

Emergency Evacuation ◽

Multi Agent Systems ◽

Agent Based ◽

Emergency Evacuations ◽

R Language ◽

Simulated Model ◽

Agent Simulation ◽

Adults And Children ◽

Multi Agent

During emergencies, emotions greatly affect human behaviour. For more realistic multi-agent systems in simulations of emergency evacuations, it is important to incorporate emotions and their effects on the agents. In few words, emotional contagion is a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes. In this study, we simulate an emergency situation in an open square area with three exits considering Adults and Children agents with different behavior. Also, Security agents are considered in order to guide Adults and Children for finding the exits and be calm. Six levels of emotion levels are considered for each agent in different scenarios and situations. The agent-based simulated model initialize with the random scattering of agent populations and then when an alarm occurs, each agent react to the situation based on its and neighbors current circumstances. The main goal of each agent is firstly to find the exit, and then help other agents to find their ways. Numbers of exited agents along with their emotion levels and damaged agents are compared in different scenarios with different initialization in order to evaluate the achieved results of the simulated model. NetLogo 5.2 is used as the multi-agent simulation framework with R language as the developing language.

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Simulated model of obesity and immediate metabolic disorders after gastric shunting with anastomosis in small laboratory animals

Klinicheskaia khirurgiia ◽

10.26779/2522-1396.2020.9-10.84 ◽

2020 ◽

Vol 87 (9-10) ◽

pp. 84-88

Author(s):

R. I. Vynogradov ◽

O. S. Tyvonchuk ◽

K. O. Nadiein ◽

V. V. Moskalenko

Keyword(s):

Small Intestine ◽

Mass Loss ◽

Body Mass ◽

Metabolic Disorders ◽

Metabolic Changes ◽

Experimental Simulation ◽

Body Mass Loss ◽

Simulated Model ◽

Group I ◽

Group Ii

Objective. To study metabolic changes and peculiarities of mineral balance depending on the common loop length while constructing of the simulated model of gastric shunting with one anastomosis during 60 days. Materials and methods. Experimental simulation of gastric minishunting with one anastomosis of various length of bilio-pancreatic loop was constructed on the rats. In 10 rats the anastomosis was formatted on level of half of total length of small intestine (Group I), and also in 10 - a third part of general length of small intestine (Group II). Control Group consisted of 5 rats. The indices of the extra body mass loss and metabolic changes were compared. Results. In the rats of Group I the index of the body mass loss have constituted 16.6% (41.7 gm), and of the Group II -20.6% (53.2 gm). Lowering of indices of mineral and prion metabolism, comparing preoperative values, was observed in both Groups. Dystrophic changes in osseous tissue of vertebral bodies of lumbar vertebral column were noted in animals of both Groups, more pronounced - in Group II. Conclusion. The protein and mineral metabolism disorders may be observed not only in large resection volume, but in exclusion of half and more segment of small bowel from general transit, using gastric shunting, what lacks significant advantages in the extra body mass loss, but leads to more profound metabolic disorders.

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EXPERIMENTAL AND CFD- SIMULATION OF POLLUTANT TRANSPORT IN POROUS MEDIA

Journal of Engineering and Sustainable Development ◽

10.31272/jeasd.25.4.3 ◽

2021 ◽

Vol 25 (4) ◽

pp. 23-39

Author(s):

Nebras Q. Hussein ◽

◽

Sadiq S. Muhsun ◽

Zainab T. Al-Sharify ◽

Huda T. Hamed ◽

...

Keyword(s):

Porous Media ◽

Physical Model ◽

Initial Velocity ◽

Cfd Simulation ◽

Pollutant Transport ◽

Pollutant Concentration ◽

Initial Porosity ◽

Noticeable Effect ◽

Inlet Velocity ◽

Simulated Model

Efforts were made in this search to design a physical and computer model using the CFD techniques to simulate the problem of transporting pollutants through a porous media in unsteady state case. A physical model was built to measure the transmission of a copper nitrate pollutant at an initial concentration of 25 mg/l in a medium consists of (sand + gravel) and study the movement of the pollutant through. Then the results of the pollutant transport through used in the physical model were entered as entry data to the CFD simulated model using COMSOL 5.4. Software. The results of the CFD simulated model showed that the change in the inlet velocity to more than 20% of the initial velocity increases the pollutant concentration and reduces the time wanted to reach the highest value of the pollutant, while reducing the inlet velocity to less than 20% of the initial velocity, cause to decrease the concentration and increase the time to reach the highest pollutant value. When changing the porosity by (30%, -15%) of the initial porosity, it was noticed that increasing the porosity value reduces the pollutant concentration and increases the time required to reach the highest value of the pollutant. while when the porosity decreases to 15% of the initial porosity, the concentration increases the time decreases to reach the highest value of the pollutant at all control points. The adsorption factor has a noticeable effect on the emergence of the pollutant, while the temperature change was almost imperceptible for all degrees. However, the results of laboratory work were compared with the results of the CFD simulated model, which showed a good match between them.

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