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Data Preprocessing
Published in Hongxing Li, C.L. Philip Chen, Han-Pang Huang, Fuzzy Neural Intelligent Systems, 2018
Hongxing Li, C.L. Philip Chen, Han-Pang Huang
A pattern is an entity to represent an abstract concept or a physical object. It may contain several attributes (features) to characterize an object. Data preprocessing is to remove the irrelevant information and extract key features of the data to simplify a pattern recognition problem without throwing away any important information. It is crucial to the success of fuzzy modeling and neural network processing and when the quantity of available data is a limiting factor. In fact, data preprocessing converts raw data and signals into data representation suitable for application through a sequence of operations. It can simplify the relationship inferred by a model. Though preprocessing is an important role, the development of an effective preprocessing algorithm usually involves a combination of problem-specific knowledge and iterative experiments. In particular, the process is very time consuming and the quality of the preprocessing may vary from case to case.
Biomodels reconstruction based on 2D medical images
Published in João Manuel, R. S. Tavares, R. M. Natal Jorge, Computational Modelling of Objects Represented in Images, 2018
P. Lopes, P. Flores, E. Seabra
Outputs from the data processing step are slice contours or 3D triangle mesh models, which are normally stored, respectively, in the form of IGES (Initial Graphics Exchange Specification) and STL (Sterolithography Text Language) format. The slice format shows cross-sections of the patient, with areas of similar brightness representing specific tissue types or regions of similar material. In order to generate the reconstructed virtual model, the patient image data must be processed to identify and extract the relevant materials corresponding to the regions of interest. The contours for each slice are interpolated and joined together to form a completed 3D object representation. In a similar way as the patient data, the models may also be processed using 3D CAD to incorporate other objects, like fixation devices and implants. The 3D CAD may also be used to produce patterns in order to make fixtures or templates. Once the virtual model has been completed, the data are translated into a triangular surface tessellated, STL, file (Popat et al. 1998. Winder & Bibb 2005).
Metals I: Metals Preparation and Manufacturing
Published in Ronald Scott, of Industrial Hygiene, 2018
Casting may be done in permanent molds, which are repeatedly reused. This is particularly true for lower melting metals. However, casting is most often done in molds of shaped sand, which is high-melting silica (quartz). This is very common for casting iron, but is also used for bronze, aluminum, and other metals. Sand is placed in a holder called the flask and an exactly shaped depression is made in the sand using a pattern. Patterns are the products of skilled workers, may be made of wood, metal (iron or bronze), or plastic, and are reused many times. If the object to be formed is hollow, a core is suspended in the sand hollow formed by the pattern. The sand of a core shape must adhere more strongly than sand in flasks, so this form is usually prepared differently. Often the mold has two flasks that each have a depression in the sand and are bolted together to provide the complete shape of the final product (Figure 18.2). In this case the top flask is called the cope and the bottom is called the drag. A hole to allow the metal to enter the mold, a sprue, must either be part of the pattern or be cut into the sand. The molten metal in this channel replaces metal volume shrinkage during cooling in the mold, keeping the mold full. Gas vent holes and risers, channels through which molten metal rises to show that the mold is full, are sometimes added.
A computer software developed for designing woven patterns and generating machine readable files for sampling looms
Published in The Journal of The Textile Institute, 2023
Woven fabrics are textile structures produced on a loom by interlacing at least two sets of yarns (warp and weft) at right angles to one another. The distribution of interlacement is called as weave design or pattern. Graphical representations of the weaves can be shown by a grid in which columns represent warp and rows represent weft. Each square represents the intersection of a warp yarn and a weft yarn. A mark in a square indicates that end goes over pick while a blank square indicates that the pick is over the end. In the case of color effect presentation, the squares are painted with the color of warp or weft yarns depending on the interlacement of yarns. Conventionally designers draw out the pattern on a squared paper. However, while drawing patterns on paper especially with different color effects, plenty of time is wasted even for a pattern that outlooks for only a piece of fabric. Therefore, Computer Aided Design (CAD) tool has become an essential part of the development and sampling process of the woven fabric design. CAD systems allow designers to display and modify patterns very quickly before weaving the fabric (Cristian & Piroi, 2016; Hu, 2004; Behera et al., 2012; Mathur & Seyam, 2011).
From architects’ terms to computable descriptions of spatial qualities
Published in Spatial Cognition & Computation, 2021
Christopher Alexander’s A Pattern Language is a collection of architectural patterns like a dictionary of patterns. A pattern is a description of a design situation that occurs over and over again within a context. Each pattern is a problem-solution set which consists of a problem statement, a verbal description, suggested principles and solution statement, and diagrams. Patterns range from the scale of a city to construction and single objects. For example, the pattern A Place to wait (150) addresses bus stops in the same way as waiting rooms in a surgery. The pattern proposes that there needs to be a mixture of activities – e.g., pool tables, newspaper, and coffee – in a waiting room as well as quiet waiting areas for positive silence. His language, a set of patterns, is the result of over ten years of observation on how people use the built environment. The patterns were created in collaboration with teams of professionals and students; they were tested, surveyed, and verified in a way or the other. Here the purpose, as stated in the second goal of the analysis, is to see if the major terms can be broken down to quantifiable functions.
4D printing of polyurethane paint-based composites
Published in International Journal of Smart and Nano Materials, 2019
Jheng-Wun Su, Wenxin Gao, Khoinguyen Trinh, Stuart M. Kenderes, Ezgi Tekin Pulatsu, Cheng Zhang, Alan Whittington, Mengshi Lin, Jian Lin
The 3D printer (Prusa i3) that was used for printing was modified by replacing the original extrusion nozzle with a digital air syringe dispenser (Loctite 883,976). Depending on the CMC concentration, the pump pressure was varied from 3 to 50 psi. The preparation of the printing material started from mixing CMC (Whatman CMC pre-swollen microgranular cation exchanger CM52) or SiO2 polyurethane paint (RUST-OLEUM triple thick polyurethane clear matte). After being vigorously stirred for 5 min the PU composites became viscoelastic paste. These PU composites were then loaded into a syringe with a nozzle of 600 µm in diameter. The patterns were designed by CAD software (SOLIDWORKS).