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The ranking of fuzzy numbers has an important position in fuzzy application models and systems. In this paper, a two-dimensional approach is proposed by the Monte Carlo simulation technique, and the simulation formula of the possibility degree is established. The algorithms for ranking interval numbers, triangular fuzzy numbers and trapezoidal fuzzy numbers are elaborated on. Moreover, the axiomatic properties of the possibility degree formulae are investigated. It is found that the simulation formula of the possibility degree is reasonable for the satisfaction of the considered axiomatic properties. Finally, by considering a set of fuzzy numbers and the effect of a viewpoint, some comparisons are reported by carrying out numerical examples. The observations reveal that the proposed simulation method is effective to reflect the uncertainty of fuzzy numbers and coherent with the human intuition.

BackgroundThe utility of T wave alternans (TWA) in identifying arrhythmia risk has been demonstrated. During myocardial ischemia (MI), TWA could be induced by cellular alternans. However, the relationship between cellular alternans patterns and TWA patterns in MI has not been investigated thoroughly. MethodsWe set MI conditions to simulate alternans. Either prolonging Ca2+ release or increasing spark-induced sparks (secondary sparks) can give rise to different patterns of APD alternans and TWA. In addition, different ischemic zones and reduced conduction velocity are also considered in one dimensional simulation. ResultsDelay of Ca2+ release can produce discordant Ca2+-driven alternans in single cell simulation. Increasing secondary sparks leads to concordant alternans. Correspondingly, morphology and magnitude of TWA vary in two different cellular alternans. Epi ischemia results in alternans concentrating in the first half of T wave. Endo and transmural ischemia lead to fluctuations in the second half of T wave. In addition, slowing conduction velocity has no effect on TWA magnitude. ConclusionSpecific ionic channel dysfunction and ischemic zones affect TWA patterns.

Oscillons are long-lived, localized, oscillating nonlinear excitations of a real scalar field which can be abundantly produced during preheating after inflation. We give the first $(3+1)$-dimensional simulation for the oscillon formation during preheating with noncanonical kinetic terms, e.g. the Dirac-Born-Infeld form, and find that the formation of oscillons is significantly influenced by the noncanonical effect., Comment: 5 pages, 4 figures; more results added, version accepted for publication in PLB

Equipment performance improvement in a wide range of working conditions is one of the major goals of aerodynamics. This goal can be achieved by the deformation of the object being examined or by using flow control techniques in active or inactive modes. In different researches, how to change the development ratio on the semi-confined space with input jet system is surveyed. In this study, two-dimensional simulation of the flow has been investigated in three-jet laminar flow in a semi-confined space. To determine the effective and optimal mixing in a laminar flow, critical Reynolds numbers were determined to distinguish when the flow in the channel from a steady-state symmetric flowformed downstream recirculation and ultimately transient flow. To better understand the flow characteristics, the simulations were changed at a fixed jet spacing (input jets distance to height of space ratio). Also, in this paper, for comparison, four jets were considered. Based on the results, it was observed that in all cases, mixing occurred in the space between three jets. Placing the jet along the walls of the semi-confined space allows the best combination, and increase in the distance between the first and third jets and reduction of the particle coefficient caused to reach the critical Reynolds number faster and, as a result, mixing in a laminar flow with geometric changes of the semi-confined space.

This study is to investigate the possibility of using activated carbon prepared from Iraqi date-pits (ADP) which are produced from palm trees (Phoenix dactylifera L.) as low-cost reactive material in the permeable reactive barrier (PRB) for treating lead (Pb+2) from the contaminated groundwater, and then compare the results experimentally with other common reactive materials such as commercial activated carbon (CAC), zeolite pellets (ZP). Factors influencing sorption such as contact time, initial pH of the solution, sorbent dosage, agitation speed, and initial lead concentration has been studied. Two isotherm models were used for the description of sorption data (Langmuir and Freundlich). The maximum lead sorption capacities were measured for ADP, CAC, and ZP and were found to be 24.5, 12.125, and 4.45 mg/g, respectively. The kinetic data were analyzed using various kinetic models particularly pseudo-first-order, pseudo-second-order, and intraparticle diffusion. COMSOL Multiphysics 3.5a depend on finite element procedure was applied to formulate transmit of lead (Pb+2) in the two-dimensional numerical (2D) model under an equilibrium condition. The numerical solution shows that the contaminant plume is hindered by PRB.

Background Performing laparoscopic liver resection for giant hemangiomas is challenging, and careful preoperative planning is essential. Controlling intraoperative bleeding and handling surgical instruments within a limited workspace is necessary. Case presentation In the present case, the patient was a 38-year-old woman diagnosed with a 16-cm giant liver hemangioma in segment 5/6, with extrahepatic growth. Preoperative three-dimensional simulations for port placement and the laparoscopic view from the left upper abdomen were performed to complete the pure laparoscopic liver resection. The laparoscopic resection was then safely performed on the same way. Conclusions Pure laparoscopic resection could be applied to giant hemangiomas with extrahepatic growth, and the preoperative three-dimensional simulation of port placement and the laparoscopic view might be helpful when the intraabdominal workplace is restricted. Electronic supplementary material The online version of this article (10.1186/s40792-019-0607-8) contains supplementary material, which is available to authorized users.

Roll waves are frequently observed in the spillway chutes of hydropower stations, flood discharge channels, and diversion canals. In order to understand the physical characteristics of roll...

Communication of goals and realistic expectations between the surgeon and patient is a crucial step of aesthetic rhinoplasty. Three-dimensional (3D) imaging technology allows for sharing of simulated outcomes in the office setting, thereby facilitating this process. This article highlights the use of 3D rhinoplasty simulation in preoperative assessment and the senior author’s preferred surgical technique in open rhinoplasty.

It is important to be able to predict the yield and monitor the growth conditions of crops in the field to increase productivity. One way to assess field-based geospatial crop productivity is by integrating a crop model with a remote-controlled aerial system (RAS). The objective of this study was to simulate spatiotemporal barley growth and yield based on the development of a crop-modeling system integrated with RAS-based remote sensing images. We performed field experiments to obtain ground truth data and RAS images of crop growth conditions and yields at Chonnam National University (CNU), Gwangju, South Korea in 2018, and at Gyeongsang National University (GNU), Jinju, South Gyeongsang, South Korea in 2018 and 2019. In model calibration, there was no significant difference (p = 0.12) between the simulated barley yields and measured yields, based on a two-sample t-test at CNU in 2018. In model validation, there was no significant difference between simulated yields and measured yields at p = 0.98 and 0.76, according to two-sample t-tests at GNU in 2018 and 2019, respectively. The remote sensing-integrated crop model accurately reproduced geospatial variations in barley yield and growth variables. The results demonstrate that the crop modeling approach is useful for monitoring at-field barley conditions.

Background: The relationship between the lateral femoral anatomic structures and femoral tunnel outlet according to changes in knee flexion and transverse drill angle during femoral tunnel creation in anterior cruciate ligament (ACL) reconstruction remains unclear. Purpose: To investigate the relationships between the lateral femoral anatomic structures and femoral tunnel outlet according to various knee flexion and transverse drill angles and to determine appropriate angles at which to minimize possible damage to the lateral femoral anatomic structures. Study Design: Controlled laboratory study. Methods: Simulation of ACL reconstruction was conducted using a 3-dimensional reconstructed knee model from the knees of 30 patients. Femoral tunnels were created using combinations of 4 knee flexion and 3 transverse drill angles. Distances between the femoral tunnel outlet and lateral femoral anatomic structures (minimum safe distance, 12 mm), tunnel length, and tunnel wall breakage were assessed. Results: Knee flexion and transverse drill angles independently affected distances between the femoral tunnel outlet and lateral femoral anatomic structures. As knee flexion angle increased, the distance to the lateral collateral ligament, lateral epicondyle, and popliteal tendon decreased, whereas the distance to the lateral head of the gastrocnemius increased ( P < .001). As the transverse drill angle decreased, distances to all lateral femoral anatomic structures increased ( P < .001). Considering safe distance, 120°, 130°, or 140° of knee flexion and maximum transverse drill angle (MTA) could damage the lateral collateral ligament; 130° or 140° of knee flexion and MTA could damage the lateral epicondyle; and 110° or 120° of knee flexion and MTA could damage the lateral head of the gastrocnemius. Tunnel wall breakage occurred under the conditions of MTA – 10° or MTA – 20° with 110° of knee flexion and MTA – 20° with 120° of knee flexion. Conclusion: Approximately 120° of knee flexion with MTA – 10° and 130° or 140° of knee flexion with MTA – 20° or MTA – 10° could be recommended to prevent damage to the lateral femoral anatomic structures, secure adequate tunnel length, and avoid tunnel wall breakage. Clinical Relevance: Knee flexion angle and transverse drill angle may affect femoral tunnel creation, but thorough studies are lacking. Our findings may help surgeons obtain a stable femoral tunnel while preventing damage to the lateral femoral anatomic structures.

Despite preceding studies of transients in non-Newtonian fluids that use two-dimensional (2D) models to predict the velocity gradient required to estimate unsteady losses, this study propos...

The advent of stricter emission standards has increased the importance of aftertreatment devices and the role of numerical simulations in the evolution of better catalytic converters in order to satisfy these emission regulations. In this paper, a 2-D numerical simulation of a single channel of the monolith catalytic converter is presented by using detailed surface reaction kinetics aiming to investigate the chemical behaviour inside the converter. The model has been developed to study the conversion of carbon monoxide (CO) in the presence of propene (C3H6) for low-temperature combustion (LTC) engine application. The inhibition effect of C3H6 over a wide range of CO inlet concentrations is investigated. Considering both low and high levels of CO concentration at the inlet, the 2-D model predicted better results than their corresponding 1-D counterparts when compared with the experimental data from literature. It was also observed that C3H6 inhibition at high temperatures was significant, particularly for high concentrations of CO compared to low concentrations of CO at the inlet.

Simulations of near-longitudinally pumped dye laser amplifiers are demonstrated in this paper. We developed a two-dimensional model that considers the amplified spontaneous emission (ASE). The influence of the angle between the input beam and pump beam on the extraction efficiency, ASE, and heating process of the amplifiers is investigated. It was found that for the main amplifiers with high pump and input powers, both the extraction efficiency and the ASE are insensitive to variations in the pump angle. However, for preamplifiers with a low input power, the increase in the angle causes a more significant loss in efficiency and a higher ASE generation. For the heating caused by light, the influence of the pump angle is insignificant. The results suggest that near-longitudinal pumping is appropriate for main amplifiers but not for preamplifiers.

A 2D TFET with two symmetrical source pocket doping is presented in this paper. The structure of TFET proposed here is symmetric having double gate along with two heavily doped pocket regions at the source that enhances the source tunnelling which in turn increases the ON current and provides negligible ambipolar conduction, which is the ramification of conventional TFET structures along with its suitability for low power applications. The gate length is varied to 24nm, 14nm and 7nm and these three structures are compared. Nevertheless, in all the three cases, Silvaco Atlasbased simulation is performed where the channel length is considered 24nm. The proposed structure(s) is suitably validated with simulated outcomes. All the simulations in this work are accomplished with Silvaco, Atlas.

This article provides an original method for simulating the spread of hazardous emissions in the atmospheric surface layer in the event of emergencies The modeling process implies the development o...

The results of time-dependent one-dimensional modelling of a dielectric barrier discharge (DBD) in a nitrogen–oxygen–water vapor mixture at atmospheric pressure are presented. The voltage–current characteristics curves and the production of active species are studied. The discharge is driven by a sinusoidal alternating high voltage–power supply at 30 kV with frequency of 27 kHz. The electrodes and the dielectric are assumed to be copper and quartz, respectively. The current discharge consists of an electrical breakdown that occurs in each half-period. A detailed description of the electron attachment and detachment processes, surface charge accumulation, charged species recombination, conversion of negative and positive ions, ion production and losses, excitations and dissociations of molecules are taken into account. Time-dependent one-dimensional electron density, electric field, electric potential, electron temperature, densities of reactive oxygen species (ROS) and reactive nitrogen species (RNS) such as: O, O−, O+, O2-documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ { ext{O}}_{2}^{ - } $$end{document}, O2+documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ { ext{O}}_{2}^{ + } $$end{document}, O3, N,N2+documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ { ext{N}}, { ext{N}}_{2}^{ + } $$end{document}, N2s and N2-documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ { ext{N}}_{2}^{ - } $$end{document} are simulated versus time across the gas gap. The results of this work could be used in plasma-based pollutant degradation devices.

In the spark-ignition engine development and optimization process, the cyclic variability of combustion is an essential and current issue. Cycle-to-cycle variations are extensively investigated by ...

We present a narrated video simulation (Video 1) using 3-dimensional anatomic software demonstrating the proper landmarks and relevant neuroanatomy for successful bedside external ventricular drain placement. External ventricular drains are commonly inserted at the bedside for emergent intracranial pressure monitoring and/or treatment of elevated intracranial pressure by cerebrospinal fluid drainage.1 Often, neurosurgical trainees perform this procedure early in their residency years.2,3 The relationship of the ventricle to the external skull landmarks may be a difficult concept to grasp for junior trainees who have had limited procedural experience. Multiple catheter passes in attempt to cannulate the ventricle are associated with increased procedural risk to the patient.2,4 Two common catheter misplacement locations leading to multiple catheter passes are lateral to the ventricle and anterior to the ventricle. In this video we highlight the relationship of the borders of the lateral ventricle to the insertion point at the skull during catheter placement. By using this resource for resident education, patient safety factors and resident procedural competence may be enhanced.

The design procedure of regulators recommends the installation of weirs to help in dissipating kinetic energy of water and controlling the hydraulic jump downstream. With the construction of new regulators, the weir downstream the old one is no longer needed and obstruct the water way. These problems appeared downstream Rosetta and Damietta Barrages, for example. The objective of this paper is to study the behavior of weirs downstream of a hydraulic regulator with opened multiple sluice vertical gates. The one Dimensional Simulation Model SOBEK will be used in this study. The regulator considered for this analysis is Tesaa Regulator which was built in 1832 and is located across Bahr Moues at km 36.0. The first scenario suggested changing the dimensions of the existing weir with the existing bed levels. The second one considered dredging the canal to the design levels and keeping the dimensions of the existing weir as is. The second scenario is considered to be more expensive than the first one. It was, however, recommended to adopt the second scenario as it preserves the old regulator which is considered an Islamic archeological structure.

Purpose – The purpose of this paper is to carry out a finite element simulation of a physically non-linear phase change problem in a two-dimensional space without adaptive remeshing or moving-mesh algorithms. The extended finite element method (XFEM) and the level set method (LSM) were used to capture the transient solution and motion of phase boundaries. It was crucial to consider the effects of unequal densities of the solid and liquid phases and the flow in the liquid region. Design/methodology/approach – The XFEM and the LSM are applied to solve non-linear transient problems with a phase change in a two-dimensional space. The model assumes thermo-dependent properties of the material and unequal densities of the phases; it also allows for convection in the liquid phase. A non-linear system of equations is derived and a numerical solution is proposed. The Newton-Raphson method is used to solve the problem and the LSM is applied to track the interface. Findings – The robustness and utility of the method are demonstrated on several two-dimensional benchmark problems. Originality/value – The novel procedure based on the XFEM and the LSM was developed to solve physically non-linear phase change problems with unequal densities of phases in a two-dimensional space.

In this research work, a two-dimensional model for randomly dispersed single-walled carbon nanotubes (SWCNT) in polymer hosts was used to predict the electrical percolation threshold (EPT) of the resulted composites in different concentrations of CNT. This was performed under a fixed DC voltage for different polymer matrices, such as high-density polyethylene, polymethyl methacrylate, polystyrene, polycarbonate, and polyethylene terephthalate via finite element method (FEM). The predicted EPT values in different composites were validated by experimental results published by other scientists. Results show that the electrical conductivity of the composites was strongly dependent on CNT weight percentages. Also, adding CNTs to the polymer matrix caused a decrease in the tunneling distance for various polymers in composites. Our results show that FEM could capture more details in the prediction of EPT in the nanocomposites.