Evaluation of metal objects surface parameters informativity using 2D­ and 3D­data For classification of fractures

This article describes evaluation the information content of metal objects surfaces for classification of fractures using 2D and 3D data. As parameters, the textural characteristics of Haralick, local binary patterns of pixels for 2D images, macrogeometric descriptors of metal objects digitized by a 3D scanner are considered. The analysis carried out on basis of information content estimation to select the features that are most suitable for solving the problem of metals fractures classification. The results will be used for development of methods for complex forensic examination of complex polygonal surfaces of solid objects for automated system for analyzing digital images.

PERPINDAHAN PANAS HYBRID PHOTOVOLTAIC DAN THERMOELEKTRIC GENERATOR DENGAN HOT MIRROR

Heat transfer is the transfer of energy from one area to another due to the temperature difference between these areas. Wasted heat energy can be converted into electricity using (TEG) between the hot and cold sides. If the temperature difference is more significant, the efficiency may increase along with the operating temperature of the TEG-type material. So in this study, the author will calculate the heat transfer that occurs in Photovoltaic (PV), Thermoelectric Generator (TEG), and Hot Mirrors by utilizing thermal energy light produced from Muxindo LED bulbs with 10 Watt, 15 Watt, and 20 Watt power. The results of this study indicate that by using 10, 15, and 20 Watt LED bulbs for free convection heat transfer, the power generated from each point increases because it passes through several obstacles from objects that experience a decrease in temperature to PV and TEG, with the characteristics of the displacement. The movement of molecules from the medium importance follows convection heat at every point of transfer in the intermediate substance. The most significant power generated from radiant heat transfer is about 0.1873 Watt. It occurs on the surface of the fresnel lens using a 20 Watt LED bulb with the characteristic that the radiation propagates in a straight line and does not require an intermediate medium to transfer heat from one substance to another. The most significant conduction heat transfer power, 0.2453 Watt, occurs in Fresnel Lens using a 20 Watt LED bulb with heat transfer characteristics in solid objects.

Robotic Spatial Printing For Designers

<p>This research developed a fully-integrated robotic printing system, using new methods of additive manufacture (AM) that enables users to explore spatially printed structures with increased freedom of geometric complexity. Current AM technologies, such as Fusion Deposition Modelling (FDM), can rapidly translate design ideations into solid forms by precisely depositing consecutive layers of material in coordination with the movements of a robotic platform. Using this method, solid objects are digitally deconstructed into linear toolpaths and physically reconstituted with thermoplastic extrusion equipment; the toolpath becomes the form. Spatial printing, using methods such as those demonstrated in this research, offers a new way of building 3D forms. By harnessing the potential of FDM equipment and materials for generating self-supporting structures, the user can create complex free-standing structures unshackled from the layered constraints of typical additive manufacturing processes. Here, the user acts as an informed negotiator between digital form and physical manifestation where movement realises form. A complete spatial printing system was built that harnesses the complexity of robotic movements and responds to the needs of printing materials through a feedback loop that draws from the results of experimentation. Bespoke printing equipment and computational processes strive to improve the craft qualities and printability of input materials with a specific focus on compatibility with co-extrusion biopolymer filaments developed by Scion. This thesis illustrates the development of a versatile spatial printing system and subsequent investigations into the craft qualities and freedom of complexity that this system offers to designers and architects.</p>

Robotic Spatial Printing For Designers

<p>This research developed a fully-integrated robotic printing system, using new methods of additive manufacture (AM) that enables users to explore spatially printed structures with increased freedom of geometric complexity. Current AM technologies, such as Fusion Deposition Modelling (FDM), can rapidly translate design ideations into solid forms by precisely depositing consecutive layers of material in coordination with the movements of a robotic platform. Using this method, solid objects are digitally deconstructed into linear toolpaths and physically reconstituted with thermoplastic extrusion equipment; the toolpath becomes the form. Spatial printing, using methods such as those demonstrated in this research, offers a new way of building 3D forms. By harnessing the potential of FDM equipment and materials for generating self-supporting structures, the user can create complex free-standing structures unshackled from the layered constraints of typical additive manufacturing processes. Here, the user acts as an informed negotiator between digital form and physical manifestation where movement realises form. A complete spatial printing system was built that harnesses the complexity of robotic movements and responds to the needs of printing materials through a feedback loop that draws from the results of experimentation. Bespoke printing equipment and computational processes strive to improve the craft qualities and printability of input materials with a specific focus on compatibility with co-extrusion biopolymer filaments developed by Scion. This thesis illustrates the development of a versatile spatial printing system and subsequent investigations into the craft qualities and freedom of complexity that this system offers to designers and architects.</p>

Mathematical modeling of monochromatic acoustic wave diffraction on a system of bodies and on flat screens

Some problems of diffraction of a monochromatic acoustic wave on surfaces of complex shapes are considered. To solve such problems, an approach is applied, in which the problem is reduced to a boundary hypersingular integral equation, where the integral is understood in the sense of a finite value according to Hadamard. Such approach allows solving diffraction problems both on solid objects and on thin screens. To solve the integral equation, the method of piecewise constant approximations and collocations, developed in the previous works of the author, is used. In the present study, examples of modeling the diffraction of an acoustic wave by bodies with partial filling are given. It is shown how the filling of bodies influences the acoustic pressure field, and the field direction patterns are given. An example of applying this approach to solving the problem of sound propagation in an urban area is also given: the diffraction of an acoustic wave from a point source on a system of buildings is considered. The presented results demonstrate that this method allows constructing reflected fields and analyze their characteristics on surfaces of complex shapes.

Systematic Compounding of Ceramic Pastes in Stereolithographic Additive Manufacturing

In this paper, stereolithographic additive manufacturing of ceramic dental crowns is discussed and reviewed. The accuracy of parts in ceramic processing were optimized through smart computer-aided design, manufacturing, and evaluation. Then, viscous acrylic resin, including alumina particles, were successfully compounded. The closed packing of alumina particles in acrylic pastes was virtually simulated using the distinct element method. Multimodal distributions of particle diameters were systematically optimized at an 80% volume fraction, and an ultraviolet laser beam was scanned sterically. Fine spots were continuously joined by photochemical polymerization. The optical intensity distributions from focal spots were spatially simulated using the ray tracing method. Consequently, the lithographic conditions of the curing depths and dimensional tolerances were experimentally measured and effectively improved, where solid objects were freely processed by layer stacking and interlayer bonding. The composite precursors were dewaxed and sintered along effective heat treatment patterns. The results show that linear shrinkages were reduced as the particle volume fractions were increased. Anisotropic deformations in the horizontal and vertical directions were recursively resolved along numerical feedback for graphical design. Accordingly, dense microstructures without microcracks or pores were obtained. The mechanical properties were measured as practical levels for dental applications.

Processing Point Clouds Using Simulated Physical Processes as Replacements of Conventional Mathematically Based Procedures: A Theoretical Virtual Measurement for Stem Volume

Conventional mathematically based procedures in forest data processing have some problems, such as deviations between the natural tree and the tree described using mathematical expressions, and manual selection of equations and parameters. These problems are rooted at the algorithmic level. Our solution for these problems was to process raw data using simulated physical processes as replacements of conventional mathematically based procedures. In this mechanism, we treated the data points as solid objects and formed virtual trees. Afterward, the tree parameters were obtained by the external physical detection, i.e., computational virtual measurement (CVM). CVM simulated the physical behavior of measurement instruments in reality to measure virtual trees. Namely, the CVM process was a pure (simulated) physical process. In order to verify our assumption of CVM, we developed the virtual water displacement (VWD) application. VWD could extract stem volume from an artificial stem (consisted of 2000 points) by simulating the physical scenario of a water displacement method. Compared to conventional mathematically based methods, VWD removed the need to predefine the shape of the stem and minimized human interference. That was because VWD utilized the natural contours of the stem through the interaction between the point cloud and the virtual water molecules. The results showed that the stem volume measured using VWD was 29,636 cm3 (overestimation at 6.0%), where the true volume was 27,946 cm3. The overall feasibility of CVM was proven by the successful development of VWD. Meanwhile, technical experiences, current limitations, and potential solutions were discussed. We considered CVM as a generic method that focuses the objectivity at the algorithmic level, which will become a noteworthy development direction in the field of forest data processing in the future.

Mechanical Properties of Concrete with Recycled Plastic Waste

Plastics are a vast group of synthetic or semi-synthetic materials that are often made of polymers. Because of their plasticity, plastics can be molded, extruded, and pressed into solid objects of different sizes. Its extensive use is due to its flexibility, as well as a number of other properties such as light weight, durability, and low manufacturing costs. The high use of plastics has resulted in an increase in solid waste, with domestic waste accounting for a significant portion of it. Since this waste is not biodegradable and takes up a lot of space, it is considered a serious environmental problem. To overcome these adverse effects, recycling plastic waste and using it in concrete can be an effective way to protect the environment. In this study, an attempt was made to experimentally evaluate the mechanical properties of concrete with recycled PET plastic wastes. The effect of this type of plastic waste was investigated by adding it in three different lengths: 22 mm, 45 mm, and a combination of both lengths 22 + 45 mm. For each length of fiber, it was added in three percentages to concrete 0.1, 0.3 and 0.5 % of cement weight. Several experiments were carried out on concrete mixtures such as slump test, compressive test, splitting tensile test, flexural test, and ultrasound pulse velocity test. The findings showed that PET waste in the form of fibers could be incorporated into concrete and achieve adequate compressive strength. When the ultrasound test results were compared to the results of previous tests, it was discovered that normal concrete containing plastic waste in the form of fibers performed exceptionally well.

3D printed patient-specific bone models for anatomy education from medical imaging

Evolution of 3D printing from medical image datasets are escalating and has widespread in healthcare applications such as anatomical models, surgical guides, and customized implants. In 3D printing, solid objects are fabricated by the frequently added the thin layers of material as per the digital model. This paper demonstrates the fabrication of 3D printed patient-specific bone models of leg and ankle foot from Digital Imaging and Communications in Medicine (DICOM) files. Processing of DICOM file is prepared by D2P (DICOM to PRINT) software and physical models are produced by Stratasys uPrint 3D printer. This 3D printed anatomical model eliminates the requirement of actual human bones, significance of preservation and mistakes in assembly of bones. The results of the study not only encourage education, surgical planning and validating medical devices but stimulate exciting innovations.