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Topology optimization (TO) has become a new paradigm to provide a quantitative design methodology for modern devices. In the two categories, the discrete-variable-based one and the continuous-variable-based one, of the existing TO methodologies, the on/off method – a typical method of the former – outperforms the latter in terms of an intuitive representation of the optimized results. Moreover, the existing TO techniques or procedures are generally 2-D. To address the aforementioned issues of existing methodologies, a new 3-D TO method based on the min-cut theorem is proposed. Three types of element connectivity are defined and used to transform a 3-D mesh grid to a 2-D network, providing equivalent quantities to perform the 3-D TO under the same implementation as in 2-D with no additional cost. Furthermore, the mechanism of the parameter selection is explored to provide rules for parameter tuning in engineering applications. As demonstrated by the reported numerical results, the proposed methodology is characterized by straightforward policy of parameter tuning and can find the optimized checkerboard-free topology with significant performance improvements.

In this article, we are reporting about the effect of energy and number density of hot primary electrons on plasma parameters in a new experimental configuration of a double plasma device. Here, we have controlled the plasma parameters in two plasma regions by a single discharge circuit. The discharge voltage is applied between hot filaments and a mesh grid. The energy of the hot primary electrons is increased by increasing the discharge voltage, and their number density is increased by increasing the filament heating voltage. It has been observed that the variations in plasma parameters are significant when the number density of primary electrons is increased.

In this paper, the flow problem of constant velocity of a square cavity whose lid is solved and obtained a numerical solution on 2 grid levels, having 32x32 and 64x64 cells. Reynolds number of 1x102 , 1x103 was selected for laminar flow and 8x103 was selected for turbulent flow. The problem is identified in NavierStokes equations. The finite volume discretization is based on the numerical model. The simulated results are in valid agreement with those that are available in the given report. The numerical solution of these works are accurately obtained for this problem.

The projector augmented wave (PAW) method is a powerful numerical algorithm that serves as a backend, enabling efficient density functional theory (DFT) calculations through the smoothing of valence electronic descriptions. Although it is mainly used in conjunction with plane-wave basis for solid-state systems, its generality permits the combination with other types of basis functions. In the previous study, we proposed a scheme to incorporate the PAW method into the conventional quantum chemical DFT implementation based on Gauss-type function (GTF) basis (Xiong et al.

This article starts with the basic concept of virtual reality technology, expounds the relationship between virtual reality technology and interior decoration design, and analyzes the feasibility of applying this technology to interior design, and proposes the application strategy of this technology in interior decoration design. It uses the Mesh grid generation algorithm to convert complex parameters into Mesh grid data that virtual reality technology is good at, and optimizes the parts; edge detection of materials, distance determination, and collision detection to improve the quality of soft decoration design. Experimental results show that this technology can improve the performance of soft decoration design, reduce design costs, and also save a lot of time and improve design effectiveness.

Hydrodynamic models proposed for simulating flow hydraulic in rivers assume the flow in one direction and simulate the hydraulic parameters based on the one-dimensional Saint-Venant equations. In this research, a two-dimensional HEC-RAS model was used to simulate the flow in the Karun River, between Mollasani and Farsiat stations. Geographic information system (GIS) and river cross sections were used to prepare the altitude map using the satellite image of the study area. Modeling results in river bends showed that the maximum velocity occurred in the outer bend, which coincided with the flow mechanism in the bends. Based on the results, grid type and density have little effect on flow depth modeling. However, the characteristics of the mesh used had a great influence on the velocity distribution, so that the regular high-density mesh had the best accuracy in simulating the flow velocity. Statistical analysis showed that the RMSE for the flow discharge and flow depth were 17.95 m3/s and 0.05 m, respectively. In addition, the Nash–Sutcliffe efficiency index was calculated to be above 0.9 for the discharge and flow depth, which could be considered as a desirable value.

We report on a co-planar light-actuated digital microfluidics device that features a metal mesh grid integrated on the device surface to allow droplets to be exposed from above. We discuss a theoretical circuit model for our co-planar optoelectrowetting (OEW) design that allows for the optimization of droplet actuation while maintaining reliable droplet movement. Basic droplet manipulations such as merging and parallel actuation of droplets are achieved at speeds of up to 4.5 cm / s. The co-planar OEW device design benefits from having an open top design that allows for a wider range of system integration configurations than previous generations of OEW devices. A droplet-on-demand dispensing system from above is integrated with the co-planar OEW device to demonstrate the versatility of this optofluidic platform. The ability to inject, collect, and position individual droplets to form large-scale droplet arrays of up to 20 × 20 is achieved.

Differential models for the simulation of the muscle mechanics are based on iteratively updating a mesh grid and deducing its new state through a finite element model. Models usually assume that the mesh grid is almost regular, and this makes a degradation of the simulation accuracy in long simulation sequences, since the mesh tends to be less regular when the number of iterations increases. We present a model that has the aim of reducing this accuracy degradation. It is based on recomputing the mesh grid returned by the model in each iteration through the concept of graph matching. The new model is currently in use to analyse the dynamics of the human heart when some pressure is applied to it. The final goal of the project (which is not shown in this paper) is to deduce the optimal position and strength pressure applied to the heart that increases the chance of reviving it with the minimum tissue damage. Experimental validation shows that our model returns a higher accuracy of the muscle position through some iterations than classical differential models with an insignificant increase of runtime. Thus, it is worth recomputing the mesh grid since the simulation accuracy drastically increases at the expense of a low runtime increase.

A numerical simulation based on a regularized phase field model is developed to describe faceted dendrite growth morphology. The effects of mesh grid, anisotropy, supersaturation and fold symmetry on dendrite growth morphology were investigated, respectively. These results indicate that the nucleus grows into a hexagonal symmetry faceted dendrite. When the mesh grid is above 640×640, the size has no much effect on the shape. With the increase in the anisotropy value, the tip velocities of faceted dendrite increase and reach a balance value, and then decrease gradually. With the increase in the supersaturation value, crystal evolves from circle to the developed faceted dendrite morphology. Based on the Wulff theory and faceted symmetry morphology diagram, the proposed model was proved to be effective, and it can be generalized to arbitrary crystal symmetries.

Many maritime transportation applications in operations research and analytics require computation of the shortest distance (or time) between two arbitrary positions on the ocean. In this paper, we show how “object meshing” used in engineering applications can be applied to provide a network over the ocean that enables such computation. We present a short description of potential applications in shipping modeling as well as a comparison of computational accuracy with an established port-to-port marine distance table. The numerical results suggest that a shortest-path algorithm applied to our network approximation of the ocean surface performs well for longer distances but relatively poorly for short voyages.

This paper presents an active FSS superstrate antenna operating at 5.25 GHz for beam steering applications. The superstrate antenna consists of metallic patches on its one side and metallic grids on its other side. The variation in the reflection phase is created by gradating the mesh grid array, which results in the phase delay of the radiated fields. The tilted radiation beam is produced due to the phase delay of the radiated fields. The proposed structure also helps in making the antenna more directive which enhances the gain while maintaining the cavity height of λ/4.

In this paper, we compute ABC index, Randic connectivity index, Sum connectivity index and GA index of grid, extended grid, torus and cylinder.

Non-thermal atmospheric pressure plasma sources are already known as an attractive devices for therapeutic applications including wound healing. The purpose of this investigation was to construct a portable device for skin wound healing. A planar atmospheric pressure Dielectric Barrier Discharge (DBD) plasma device was constructed. The effect of using mesh grid with DBD device was investigated for uniformity treatment of skin wounds. Reactive Nitrogen and Oxygen species were observed in the optical emission spectrum. The experiments were performed in two phases, using the DBD plasma device with/without mesh grid. In each phase, the comparison was performed between the naturally healed wounds and stimulated wounds treated daily (5 days) for 30 s. The reduction of wound area, morphological changes in wounds and tissue histological parameters were analysed. The wounds treated with DBD device with mesh grid were healed faster than the control wounds and the wounds treated with DBD device without mesh grid became more inflamed and they burned as well as the wound area were increased until 8th day of wounding. It is concluded that the DBD device with mesh grid has the ability of wound healing uniformly and without grid, the electrical shock imposed to the mice body prevents natural healing.

A numerical scheme for two-phase flow in gas liquid cylindrical cyclone is developed and its performance is investigated. A three-dimensional cyclone is simulated with computational fluid dynamic methods. After choosing a suitable mesh grid for the cyclone and checking grid independency, the effect of changing geometry parameters on the gas liquid cylindrical cyclone performance such as gas carry under and liquid carry over is investigated and finally the geometry is optimized to minimize both gas carry under and liquid carry over. Geometrical parameters have great effect on optimizing cyclone separators performance. Reynold’s stress model is used for turbulence simulation of the flow and two-phase flow is simulated using Eulerian–Eulerian approach. Optimized parameters are inlet nozzle width, inlet angle, inlet altitude relative to the bottom of the cyclone, cyclone main diameter, and liquid outlet diameter. Results show that gas carry under decreases with decreasing liquid outlet diameter of the cyclone, increasing main diameter of the cyclone, increasing inlet nozzle’s width, and decreasing nozzle’s inlet angle. The optimum point for gas carry under was given with changing inlet altitude relative to the bottom of the cyclone. The optimum point for liquid carry over was obtained with changing liquid outlet diameter, main diameter of the cyclone, inlet altitude, and inlet nozzle width and increasing inlet angle causes an increase in liquid carry over.

Spatial discretization is the cornerstone of all spatially-distributed numerical simulations including watershed hydrology. Traditional square grid spatial discretization has several limitations including inability to represent adjacency uniformly. In this study, we developed a watershed delineation model (HexWatershed) based on the hexagon grid spatial discretization. We applied this model to two different types of watershed in the US and we evaluated its performance against the traditional method. The comparisons show that the hexagon grid spatial discretization exhibits many advantages over the tradition method. We propose that spatially distributed hydrologic simulations should consider using a hexagon grid spatial discretization.

We report a formvar assisted transfer method to make graphene TEM grids having single layer graphene. Our method uses formvar instead of PMMA as the polymer support and produces clean graphene. Formvar was easily removed by dissolving in chloroform and did not leave residues after removal because of the lower the molecular weight. Our transfer method achieved the higher average coverage (about 55%) than direct transfer method (about 5%). Since mesh grids were not exposed to a metal etchant solution during our transfer process, the mesh grid material for graphene transfer was not limited. Our graphene transfer method produces high quality and single layer graphene for a graphene TEM grid. Consequently, the formvar assisted graphene transfer method solves disadvantages of polymer support method and direct transfer.

We propose a video stabilization algorithm, which extracts a guaranteed number of reliable feature trajectories for robust mesh grid warping. We first estimate feature trajectories through a video sequence and transform the feature positions into rolling-free smoothed positions. When the number of the estimated trajectories is insufficient, we generate virtual trajectories by augmenting incomplete trajectories using a low-rank matrix completion scheme. Next, we detect feature points on a large moving object and exclude them so as to stabilize camera movements, rather than object movements. With the selected feature points, we set a mesh grid on each frame and warp each grid cell by moving the original feature positions to the smoothed ones. For robust warping, we formulate a cost function based on the reliability weights of each feature point and each grid cell. The cost function consists of a data term, a structure-preserving term, and a regularization term. By minimizing the cost function, we determine the robust mesh grid warping and achieve the stabilization. Experimental results demonstrate that the proposed algorithm reconstructs videos more stably than the conventional algorithms.

Using a combination of close-range photogrammetry and three-dimensional (3-D) limit equilibrium theory, a determination method for the shear strength parameters of rock-soil mixture is presented. A close-range photogrammetry method is used for measurement of the 3-D terrain of the experimental target. AutoCAD Lisp and EXCEL VBA are used to perform 3-D limit equilibrium analysis of the stability of sliding mass and perform back-analysis of shear strength parameters. The presented method was used to determine the shear strength parameters of rock-soil mixtures at the Liyuan Hydropower Station. The 3-D terrain of sliding surface could be measured notably well using of close-range photogrammetry. The computed results reveal that the cohesion and friction angle of rock-soil mixtures were 3.15 kPa and 29.88o for test A, respectively, and 4.43 kPa and 28.30o for test B, respectively, within the range of shear strength parameters, as determined by field and laboratory tests. The computation of shear strength parameters is influenced by the mesh grid number, especially the cohesion of the rock-soil mixture. The application of close-range photogrammetry can reduce the site works and improve the computational efficiency and accuracy.

In this paper, the analysis results of the imitative grounding systems consisting of 4 mesh grid with rods are presented by using the Finite Element Method (FEM) and field test. This combined grid with multiple rods configuration was installed by previous researchers [4] and the resistance value is obtained under steady state. The FEM simulations were conducted and the resistance value and electric field profile are obtained. Comparison study in terms of its resistance value is performed between FEM and at steady state, and further analysis of the grounding systems using FEM is presented and discussed in this paper.

Local error estimates for the SUPG method applied to evolutionary convection---reaction---diffusion equations are considered. The steady case is reviewed and local error bounds are obtained for general order finite element methods. For the evolutionary problem, local bounds are obtained when the SUPG method is combined with the backward Euler scheme. The arguments used in the proof lead to estimates for the stabilization parameter that depend on the length on the time step. The numerical experiments show that local bounds seem to hold true both with a stabilization parameter depending only on the spatial mesh grid and with other time integrators.

This article deals with the description of IQRF technology with the aim of creation of extensive measurement and monitoring systems. These systems can be deployed autonomously at desired location, where they form a MESH grid, and provide automated measurements and sending information to the dispatching center. The paper gives a description of IQRF technology following the measurement of electrical and physico-mechanical quantities. There is also description of the development of a pilot system which will serve for monitoring of the effects of thermal processes within old mining dumps.

Size is an important factor for the Atlantic blue crab, Callinectes sapidus (Rathbun), with large male crabs often having an advantage over small crabs in mating, molting, and locomoting. The ability of larger crabs to resist fatigue may be another benefit of being big. We describe a novel pull force test that measures the force crabs use to hold onto a mesh grid, mimicking the way a male holds a female during mate guarding. In this study, we used this pull force test to determine whether larger male crabs have an advantage over smaller crabs by being able to sustain a greater pull force even after fatigue from sustained walking. Fatigue was induced by a 6-h exercise trial that entailed continuous sideways hexapedal walking on an underwater treadmill. Larger crabs maintained an advantage over smaller crabs even after fatigue. In crabs, including the Atlantic blue crab, increased size seems to have advantages. These include reproduction

Background: Self-expandable esophageal stents are increasingly used for palliation or as an adjunct to chemoradiation for esophageal neoplasia. The optimal esophageal stent design and material to minimize dose perturbation with external beam radiation are unknown. We sought to quantify the deviation from intended radiation dose as a function of stent material and mesh density design. Methods: A laboratory dosimetric film model was used to quantify perturbation of intended radiation dose among 16 different esophageal stents with varying material and stent mesh density design. Results: Radiation dose enhancement due to stent backscatter ranged from 0 % to 7.3 %, collectively representing a standard difference from the intended mean radiation dose of 1.9 (95 % confidence interval [CI] 1.5 – 2.2). This enhancement was negligible for polymer-based stents and approached 0 % for the biodegradable stents. In contrast, all metal alloy stents had significant radiation backscatter; this was largely determined by the density of mesh design and not by the type of alloy used. Conclusions: Stent characteristics should be considered when selecting the optimal stent for treatment and palliation of malignant esophageal strictures, especially when adjuvant or neo-adjuvant radiotherapy is planned.

In this study the total activity of 137 Cs deposited per unit area over the Spanish peninsular territory was analysed using a 150 × 150 km 2 mesh grid, with samples taken from 29 points. The deposited activities ranged between 251 and 6074 Bq/m 2 . A linear relationship was obtained between these values and the mean annual rainfall at each sampling point which allowed a map to be drawn, using GIS software, which shows the distribution of total deposited 137 Cs activity across the Spanish mainland. At twelve of these sampling points the vertical migration profile of 137 Cs was obtained. These profiles are separated into two groups with different behaviour, one of which includes clay and loam soils and the other containing sandy soils. For both groups of profiles the parameters of the convective–diffusive model, which describes the vertical migration of 137 Cs in the soil, v (apparent convection velocity) and D (apparent diffusion coefficient) were calculated.

Free-standing, ultralong (up to several millimeters) nanobelts of gold, silver, and copper were fabricated by a template approach. Firstly, a metal nanofin array was prepared on a substrate via metal nanocoating of the template surface and selective removal of the metal top layer and template. Electroless plating and sputtering were employed for the metal nanocoating. In this approach, the minimum width and thickness of the Au nanobelt were 95 and 30 nm, respectively. Systematic control of the nanobelt width (from 95 to 350 nm) was successfully achieved by adjusting the template height. Free-standing nanobelts of several millimeters in length were fabricated and maintained their unique structure and alignment, even on a mesh grid.

The newly designed and constructed electrostatic quadrupole doublet (EQD) at the University of North Texas (UNT) has achieved mass independent focusing of MeV particles to a spot size of 3.3 × 3.5 μm. The EQD is compared to the Louisiana magnetic doublet which is also in use at UNT. Characteristics such as demagnification and sensitivity to aberrations are simulated by the matrix raytracing software, propagation of rays and aberrations by matrices and compared for each focusing system. Particle induced x-ray emission (PIXE) maps of a 2000 mesh Cu grid are compared and show that both doublets produce suitable spot sizes for microprobe analysis. A coarser, 200 mesh grid and incident beams of 2 MeV H+ and O+ show the EQD to be stigmatic given common aperture sizes and lens potentials.

A numerical simulation based on a new regularized phase-field model is developed to describe the silicon solidification in a forced flow. The effect of forced flow, anisotropy, and mesh grid on dendritic growth shape is investigated. These results indicate that crystals grow into an equiaxial facet dendritic without flow and into an asymmetrical facet dendritic with flow, that is, upstream arm growth is promoted, and downstream inhibited, however, there is no such effect on perpendicular arms. It is also found that the asymmetrical growth feature becomes noticeable with increase in the flow velocity. With the increase in the anisotropy value, the tip velocities of upstream and downstream decrease gradually.

Standard crystalline solar cells are generally fabricated with the front grid pattern of silver paste contact. We have reported a detailed theoretical analysis of the proposed segmented cross grid line pattern in this paper. This work was carried out for the optimization of spacing and width of grid finger, main busbar and sub-busbar. The overall electrical and optical losses due to front contact were brought down to or even less as compared to the usual loss of or more in the conventional screen printed silver paste technology by choosing proper grid pattern and optimizing the grid parameters. The total normalized power loss for segmented mesh grid with plated metal contact was also observed and the total power loss could be brought down to unlike in the case of continuous grid and plated contact. This paper is able to outline the limitations of conventional screen printed contact.

Measuring ground resistance is a typical way of performance evaluation of a grounding electrode. Among various ground resistance measurement methods, FOP (Fall-Of-Potential) method has been widely used, especially in case of a relatively large grounding electrode such as a substation grounding mesh grid Since FOP measurement line has to be increased as the size of grounding electrode increases, however, it is often that securing long enough FOP-line is practically impossible. In this paper, a sophisticated interpretation method of FOP measurement ma which is applicable to large grounding electrode networks, is presented.

Nesting locations of gray-faced buzzard eagles were studied in two areas of about 348 in Tochigi prefecture. Their food items were also monitored. From the nesting data, a multiple regression model was constructed to predict the number of nesting locations within a 2x2 mesh grid from several environmental factors such as vegetation and human population size. The resulted model could explain about 70% of the variation in the number of nests (r2×0.71). Factors used in the model were length of forest edge facing paddy fields in a mesh grid and in surrounding eight meshes grids (positive factor), and population (negative factor). In the study area gray-faced buzzard eagles were feeding mainly on frogs, and the birds were observed to perch on the tree top in the forest-paddy field edge waiting for frogs to appear. The preference on forest-paddy field edge shown by the model might reflect the importance of such habitat as the species' hunting area. In our study area, the gray-faced buzzard eagles were especially abundant in continuous 'Yatsu' area, a landscape in which a low tableland is eroded by rivers to create a fractal shaped network of valleys. Our results, along with other published data, indicate that the Yatsu landscape is an important breeding habitat for this species.