Evaluation of the auto surfacing methods to create a surface body of the mandible model

Designing an anatomical structure for a surgical procedure is not a simple task. It is especially true of the craniofacial area, which consists of bone tissues with very complex geometry. CAD modelers need appropriate knowledge and skills in medicine and technical sciences to fully use the currently available tools in related processes with the reconstruction of the craniofacial areas. The presented preliminary studies are based on four patients treated at the Department of Maxillofacial Surgery. The segmentation process of the mandible model was performed in the ITK SNAP software. The process of generating surface body models was performed in the Auto Surfacing module in Geomagic software using two different methods: organic and mechanical. Then compare both methods for the accuracy of generating a CAD model of the mandible based on a triangle mesh structure in the Focus Inspection and the GOM Inspect software.

Coalescent angiogenesis—evidence for a novel concept of vascular network maturation

Angiogenesis describes the formation of new blood vessels from pre-existing vascular structures. While the most studied mode of angiogenesis is vascular sprouting, specific conditions or organs favor intussusception, i.e., the division or splitting of an existing vessel, as preferential mode of new vessel formation. In the present study, sustained (33-h) intravital microscopy of the vasculature in the chick chorioallantoic membrane (CAM) led to the hypothesis of a novel non-sprouting mode for vessel generation, which we termed “coalescent angiogenesis.” In this process, preferential flow pathways evolve from isotropic capillary meshes enclosing tissue islands. These preferential flow pathways progressively enlarge by coalescence of capillaries and elimination of internal tissue pillars, in a process that is the reverse of intussusception. Concomitantly, less perfused segments regress. In this way, an initially mesh-like capillary network is remodeled into a tree structure, while conserving vascular wall components and maintaining blood flow. Coalescent angiogenesis, thus, describes the remodeling of an initial, hemodynamically inefficient mesh structure, into a hierarchical tree structure that provides efficient convective transport, allowing for the rapid expansion of the vasculature with maintained blood supply and function during development.

Island and Field

<p>We build transport infrastructure to move about the city efficiently. However, in New Zealand, it is often one-dimensional and disconnected from the urban fabric. This is the case in Hataitai, where State Highway 1 imposes a boundary between the nearby village and the Town Belt that could be bridged when new work on the Mt Victoria Tunnel takes place. What could be the nature of a pedestrian bridge that connects these disparate urban territories? I explored this question with two distinct methods. The first used ‘fast and loose’ hand drawing and physical modelling to explore a ubiquitous mesh structure, replacing the ground plane of the site. This Field accommodated a variety of programmed elements and crossings. The second experiment replaced the mesh with an autonomous loop between the park, village and tunnel. This Island required more precise digital modelling tools and a more measured design process. The two methods offer vastly different approaches to urban design. The ubiquitous mesh replaces the existing ground by extending it. The Loop structure is an autonomous figure over the existing and messy ground of the urban junction below. The research demonstrates the tensions between these two approaches to urban intervention and how they can offer alluring moments in the everyday life of the city.</p>

Island and Field

<p>We build transport infrastructure to move about the city efficiently. However, in New Zealand, it is often one-dimensional and disconnected from the urban fabric. This is the case in Hataitai, where State Highway 1 imposes a boundary between the nearby village and the Town Belt that could be bridged when new work on the Mt Victoria Tunnel takes place. What could be the nature of a pedestrian bridge that connects these disparate urban territories? I explored this question with two distinct methods. The first used ‘fast and loose’ hand drawing and physical modelling to explore a ubiquitous mesh structure, replacing the ground plane of the site. This Field accommodated a variety of programmed elements and crossings. The second experiment replaced the mesh with an autonomous loop between the park, village and tunnel. This Island required more precise digital modelling tools and a more measured design process. The two methods offer vastly different approaches to urban design. The ubiquitous mesh replaces the existing ground by extending it. The Loop structure is an autonomous figure over the existing and messy ground of the urban junction below. The research demonstrates the tensions between these two approaches to urban intervention and how they can offer alluring moments in the everyday life of the city.</p>

Doors in the sky: Detection, localization and classification of aerial vehicles using laser mesh

Stealth technology and Unmanned Aerial Vehicles (UAVs) are expected to dominate current and future aerial warfare. The radar systems at their maximum operating ranges, however, are not always able to detect stealth and small UAVs mainly due to their small radar cross sections and/or low altitudes. In this paper, a novel technique as an alternative to radar technology is proposed. The proposed approach is based on creating a mesh structure of laser beams initiated from aerial platforms towards the ground. The laser mesh acts as a virtual net in the sky. Any aerial vehicle disrupting the path of the laser beams are detected and subsequently localized and tracked. As an additional feature, steering of the beams can be used for increased coverage and improved localization and classification performance. A database of different types of aerial vehicles is created artificially based on Gaussian distributions. The database is used to develop several Machine Learning (ML) models using different algorithms to classify a target. Overall, we demonstrated through simulations that our proposed model achieves simultaneous detection, classification, localization, and tracking of a target.

CFD MODELLING OF VOLTACAR ELECTRIC VEHICLE BODY FOR THE MOST EFFICIENT DRIVING CONDITIONS

In recent years, fossil fuels prices, greenhouse gas emissions, and need for sustainable energy sources have been increasing day by day. Thus, electric vehicles are seen as a promising candidate in the market due to their low-costs and cleaner fuel options such as electricity, hydrogen etc. Moreover, aerodynamics is one of the most important criteria to consider while designing an automobile for the most efficient driving conditions. For this reason, vehicle developers are studying to reduce drag resistance of the body to improve driving efficiency. On the other hand, Computational Fluid Dynamics (CFD) is one of the main tools for the automotive industry to obtain low-cost results before prototyping of any product. In this study, the aerodynamic characteristics of VoltaCAR electric vehicle is numerically investigated to obtain the best driving velocity. This car participates the TUBITAK-Electromobile car competition every year to achieve low fuel consumption for one hour driving. Thus, it is aimed that to minimize the resistance of the air hitting from the front, side, and roof of the vehicle. In the numerical model, polyhedral mesh structure is preferred to obtain faster convergence with fewer iterations, and shorter computation time is obtained compared to the tetrahedral mesh method. The aerodynamic drag coefficient (Cd) of the car model was calculated as approximately 0.17 at 22.22 and 27.78 m/s. The optimum velocity values were selected as 22.22 and 27.78 m/s by means of their lower Cd.

Skull Thickness Calculation Using Thermal Analysis and Finite Elements

In this study, the skull bone thicknesses of 150 patients ranging in age from 0 to 72 years were calculated using a novel approach (thermal analysis), and thickness changes were analyzed. Unlike conventional thickness calculation approaches (Beam Propagation, Hildebrand), a novel heat transfer-based approach was developed. Firstly, solid 3D objects with different thicknesses were modeled, and thermal analyses were performed on these models. To better understand the heat transfer of 3D object models, finite element models (FEM) of the human head have been reported in the literature. The FEM can more accurately model the complex geometry of a 3D human head model. Then, thermal analysis was performed on human skulls using the same methods. Thus, the skull bone thicknesses at different ages and in different genders from region to region were determined. The skull model was transferred to ANSYS, and it was meshed using different mapping parameters. The heat transfer results were determined by applying different heat values to the inner and outer surfaces of the skull mesh structure. Thus, the average thicknesses of skull regions belonging to a certain age group were obtained. With this developed method, it was observed that the temperature value applied to the skull was proportional to the thickness value. The average thickness of skull bones for men (frontal: 7.8 mm; parietal: 9.6 mm; occipital: 10.1 mm; temporal: 6 mm) and women (frontal: 8.6 mm; parietal: 10.1 mm; occipital: 10 mm; temporal: 6 mm) are given. The difference (10%) between men and women appears to be statistically significant only for frontal bone thickness. Thanks to the developed method, bone thickness information at any desired point on the skull can be obtained numerically. Therefore, the proposed method can be used to help pre-operative planning of surgical procedures.

New design of large fully-steerable radio telescope reflector based on homogenized mesh structure

The self-weight of a large fully-steerable radio telescope is one of the important factors affecting its performance. In the existing reflector system scheme, the problem of surface accuracy caused by its large and heavy structure has seriously restricted the application and implementation of large radio telescopes. Therefore, a new mesh structure scheme for a large fully-steerable radio telescope reflector is proposed in this paper. This scheme is based on a homogenized mesh back-up structure in the form of a quasi-geodesic grid and regular quasi-tri-prism or tetrahedron, which can significantly reduce the structural complexity and self-weight of the reflector under the condition that the reflector can meet the desired performance requirements. Finally, the feasibility and rationality of the scheme are evaluated by numerical simulation analysis, which has significant advantages and provides a new design for the reflector of a large fully-steerable radio telescope.

Mesh filtration problems with a two-flow structure of phase velocities

This paper deals with the problem of filtration of a two-phase incompressible fluid within the Buckley-Leverett model. From a general point of view, a two-flow structure of conservation laws is investigated. In addition, since the solution in the Buckley-Leverett model is discontinuous, conservation laws are presented in the generalized integral form. A good illustration of the approach presented is the problem of gravitational segregation of oil and water in a porous medium. For this problem, a two-flow mesh structure of conservation laws is described.

Analysis of Electromagnetic Reflection Loss for Mesh Structure with A16061 MMC for Aerospace Applications

One of the major problems facing by the aircraft was a lightning strike. To overcome this problem, fiber-reinforced materials have been used. The fiber-reinforced materials have less conductivity. These fiber-reinforced materials can’t eliminate the lightning strike effect. For that purpose, the metal matrix composite materials significantly impacted the aircraft’s internal circuits and physical components from the lightning strike effect. To meet industries dynamic and ever-increasing demands, Al6061 metal matrix composite reinforced with fly ash must be utilized to build the aircraft to offer HIRF. The material thickness should be kept low as possible then it can be used to cover the plane’s surface. To prevent lightning strikes, it might be used to protect electronic components from a concentrated high-intensity radiated field, primarily in Aeroplan configuration. The electromagnetic characteristics of composites are measured using the X-band for normal incidence. The electromagnetic reflection properties of AL6061 reinforced with fly ash are studied in this study for mesh structure. Mat lab Software was used to calculate the maximum reflection loss of 33.88dB for 15% fly ash and 85 percent AL6061 at X-band.