articles+ search results

Open source software, Public software -- Analysis, and Rapid prototyping -- Analysis

Keywords: Dynamic optimization; Dynamic simulation; Pyomo; Process control; Williams-Otto process Abstract With ongoing digitalization, fast simulation of process dynamics offers new opportunities for model-based control schemes. This is eased by the availability of high-level, open-access, easy-to-use software able to simulate and optimize chemical processes, making rapid prototyping possible also for the chemical engineer. In this study, the capabilities of the Python-based open-source software package Pyomo towards industrial application is illustrated in modeling and comparing different control schemes for a simple Williams-Otto process. It is shown how to simulate the process dynamics and how to compute optimal control trajectories for minimizing waste and maximizing yield. Two approaches to setpoint tracking are compared: one based on proportional-integral feedback control and one based on optimal open-loop control. Byline: Julia Riese, Jochen Schmid, Katrin Teichert, Moncef Chioua, Thorsten Schindler, Michael Bortz

Rapid prototyping and Autografts

Keywords: digital dentistry; endodontics; laboratory technology; oral surgery; pain Abstract Objective To describe a method to fabricate donor tooth replica to assist surgeons in preparation of recipient socket during tooth autotransplantation. Materials and Methods A total of 28 compromised molars in 27 patients were transplanted with third molars using computer-aided rapid prototyping (CARP) technique. Surgery time and extra-alveolar time were documented. Postoperatively, the distance between cervix of transplanted tooth and the alveolar wall was measured. The degree of postoperative pain experienced was assessed with visual analog scale at day 1, 3, and 7. Results From 28 clinical cases, the average extra-alveolar time and surgery time were 2.5 minutes ([+ or -]1.3) and 44minutes ([+ or -]6.8), respectively. Postoperatively, the average distance between cervix of transplanted tooth and the alveolar wall was 0.87mm ([+ or -]0.15) at the mesial-cervix, 0.95mm ([+ or -]0.17) at the distal-cervix, 0.88mm ([+ or -]0.18) at the buccal-cervix, and 0.95mm ([+ or -]0.13) at the lingual-cervix. The value of visual analog scale score significantly decreased from day 1 to day 3. Conclusions CARP is a reliable technique for fabrication of tooth like surgical replicas in conventional autotransplantation. Clinical Significance CARP technique minimized extra-oral time, reduced iatrogenic damage, and consequently increased the survival rate of tooth autotransplantation. Byline: Jia-jia Xia, Zi-yu Ge, Xiao-hui Fu, Yan-zhen Zhang

Keywords: curatorial interventions; public frictions; smart city; urban laboratory; urban prototyping Abstract The use of prototypes as testing instruments has become a common strategy in the innovation of services and products and increasingly in the implementation of 'smart' urban policies through living labs or pilots. As a technique for validating hypotheses about the future performance of products or policies, prototyping is based on the idea of generating original knowledge through the failures produced during the testing process. Through the study of an experimentation and prototyping project developed in Santiago de Chile called 'Shared Streets for a Low-Carbon District,' I analyse the technique of prototyping as a political device that can make visible (or invisible) certain entities and issues, determining what the experimental entities can do and say. I will show how the technique of prototyping defines modes of participation, what is visible and thinkable, what can be spoken and what is unspeakable. In this sense, I examine two ambivalent capacities of prototyping: as a mechanism of management and enrolment that seeks to prescribe normativities (problem-validating prototype) and as an event that can make frictions tangible, articulating matters of concern and ways to open up alternative scenarios (problem-making prototype). Byline: Martin Tironi

Market trend/market analysis, 3D printing -- Innovations, 3D printing -- Forecasts and trends, Prototypes, Engineering -- Design and construction, Prototypes, Engineering -- Forecasts and trends, Thermoforming -- Forecasts and trends, and Engineering firms -- Innovations

The use of 3D-printed tooling for thermoformed parts is an emerging development in additive manufacturing that is paying significant dividends in terms of reduced tooling cost and time for prototype [...]

Computer-aided design -- Analysis, Implants, Artificial -- Analysis, Prosthesis -- Analysis, and Rapid prototyping -- Analysis

Abstract Statement of problem Although closed hollow obturator prostheses provide the benefit of minimized weight, they also pose challenges. They are complex to fabricate, and contaminated water can easily enter the hollow section through the joined part, making them unsanitary and leading to malodor and increased weight. Purpose The purpose of this in vitro study was to investigate the hermeticity and durability of a hollow obturator model fabricated by using computer-aided design (CAD) and rapid prototyping (RP) techniques and to evaluate the possibility of its clinical use. Material and methods Leak testing was used to evaluate the hermeticity and durability of hollow spherical obturator specimens with an outer diameter of 30 mm and 2 different wall thicknesses (1.5 and 2.0 mm). Six specimens were fabricated for each of the wall thicknesses by using CAD and RP techniques. The accumulation of fluids in the hollow obturator specimens was evaluated every day by using megascopic observation with photoirradiation from the base of the specimens. The amount of water absorption and the rate of increase in the weight of the 2 specimens were calculated and compared. Statistical analysis was performed by using the Mann-Whitney U test ([alpha]=.05). Results The application of CAD and RP techniques made it possible to fabricate a hollow obturator model specimen with completely unified parts. The 1.5-mm specimen showed an absorption rate (2.61%) that significantly exceeded that of the 2.0-mm specimen (2.53%) on day 130 (P=.006). By the end of the observation period, the 1.5-mm specimen exhibited large amounts of water absorption and destruction. The 1.5-mm-thick wall had reduced hermeticity than the 2.0-mm-thick wall. Conclusions A fully unified hollow obturator model with 2.0-mm-thick walls was fabricated by using CAD and RP techniques. The absence of any joints prevented fluid accumulation, making this method suitable for the fabrication of hollow prostheses. Author Affiliation: (a) Associate Professor, Maxillofacial Prosthetics Clinic, Tohoku University Hospital, Sendai, Japan (b) Assistant Professor, Maxillofacial Prosthetics Clinic, Tohoku University Hospital, Sendai, Japan (c) Assistant Professor, Maxillofacial Prosthetics Clinic, Tohoku University Hospital, Sendai, Japan (d) Assistant Professor, Maxillofacial Prosthetics Clinic, Tohoku University Hospital, Sendai, Japan (e) Professor, Division of Advanced Prosthodontics, Graduate School of Dentistry, Tohoku University, Sendai, Japan * Corresponding author: Dr Shigeto Koyama, Tohoku University Hospital, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, JAPAN Byline: Shigeto Koyama, DDS, PhD [koyama@dent.tohoku.ac.jp] (a,*), Naoko Sato, DDS, PhD (b), Takehiko Mito, DDS, PhD (c), Kuniyuki Izumita, DDS, PhD (d), Keiichi Sasaki, DDS, PhD (e)

Rapid prototyping

***** No abstract is available for this article. Article Note: Article impact statement: Web-application development frameworks enable the creation of decision-support tool prototypes for actionable conservation science. CAPTION(S): Table 1. List of web-application development frameworks that might be useful for conservation scientists. Byline: Denis Valle, Kok Ben Toh, Justin Millar

Neural network, Electrical engineering, Neural networks -- Analysis, and Electrical engineering -- Analysis

Keywords Convolutional neural network; Hardware acceleration; Rapid system prototyping; Binarization; FPGA Abstract The huge model size and high computational complexity make emerging convolutional neural network (CNN) models unsuitable to deploy on current embedded or edge computing devices. Recently the binary neural network (BNN) is explored to help reduce network model size and avoid complex multiplication. In this paper, a binary network acceleration framework for rapid system prototyping is proposed to promote the deployment of CNNs on embedded devices. Firstly trainable scaling factors are adopted in binary network training to improve network accuracy performance. The hardware/software co-design framework supports various compact network structures such as residual block, 1 x 1 squeeze convolution layer, and depthwise separable convolution. With flexible network binarization and efficient hardware architecture optimization, the acceleration system is able to achieve over 2 TOPS throughput performance comparable to modern desktop GPU with much higher power efficiency. Author Affiliation: Department of Electrical Engineering, City University of Hong Kong, Hong Kong, China * Corresponding author. Article History: Received 2 December 2019; Revised 19 February 2020; Accepted 8 March 2020 Byline: Zhe Xu [zhexu22-c@my.cityu.edu.hk], Ray C.C. Cheung [r.cheung@cityu.edu.hk] (*)

Rapid prototyping, Proteins, Genetic research, Mail-order industry, Fluorescence, Protein biosynthesis, Genes, Escherichia coli, and DNA synthesis

Byline: Jared Lynn Dopp, Samuel Michael Rothstein, Thomas Joseph Mansell,Nigel Forest Reuel Keywords: cell-free protein synthesis; linear template; rolling circle amplification Abstract In this study, we present a minimal template design and accompanying methods to produce assayable quantities of custom sequence proteins within 24hr from receipt of inexpensive gene fragments from a DNA synthesis vendor. This is done without the conventional steps of plasmid cloning or cell-based amplification and expression. Instead the linear template is PCR amplified, circularized, and isothermally amplified using a rolling circle polymerase. The resulting template can be used directly with cost-optimized, scalably-manufactured Escherichia coli extract and minimal supplement reagents to perform cell-free protein synthesis (CFPS) of the template protein. We demonstrate the utility of this template design and 24hr process with seven fluorescent proteins (sfGFP, mVenus, mCherry, and four GFP variants), three enzymes (chloramphenicol acetyltransferase, a chitinase catalytic domain, and native subtilisin), a capture protein (anti-GFP nanobody), and 2 antimicrobial peptides (BP100 and CA(1-7)M(2-9)). We detected each of these directly from the CFPS reaction using colorimetric, fluorogenic, and growth assays. Of especial note, the GFP variant sequences were found from genomic screening data and had not been expressed or characterized before, thus demonstrating the utility of this approach for phenotype characterization of sequenced libraries. We also demonstrate that the rolling circle amplified version of the linear template exhibits expression similar to that of a complete plasmid when expressing sfGFP in the CFPS reaction. We evaluate the cost of this approach to be $61/mg sfGFP for a 4hr reaction. We also detail limitations of this approach and strategies to overcome these, namely proteins with posttranslational modifications. CAPTION(S): Supplementary information

3D printing -- Methods

1. Introduction Microfabrication techniques have revolutionized the way biologists and medical scientists conduct studies in the last few decades [1]. The well-developed semiconductor workflow enables not only the creation of [...]
C[O.sub.2] laser manufacturing has served as an enabling and reliable tool for rapid and cost-effective microfabrication over the past few decades. While a wide range of industrial and biological applications have been studied, the choice of materials fabricated across various laser parameters and systems is often confounded by their complex combinations. We herein presented a unified procedure performed using percussion C[O.sub.2] laser drilling with a range of laser parameters, substrate materials and various generated microstructures, enabling a variety of downstream tissue/cellular-based applications. Emphasis is placed on delineating the laser drilling effect on different biocompatible materials and proof-of-concept utilities. First, a polydimethylsiloxane (PDMS) microneedle (MN) array mold is fabricated to generate dissolvable polyvinylpyrrolidone/polyvinyl alcohol (PVP/PVA) MNs for transdermal drug delivery. Second, polystyrene (PS) microwells are optimized in a compact array for the formation of size-controlled multicellular tumor spheroids (MCTSs). Third, coverglass is perforated to form a microaperture that can be used to trap/position cells/spheroids. Fourth, the creation of through-holes in PS is validated as an accessible method to create channels that facilitate medium exchange in hanging drop arrays and as a conducive tool for the growth and drug screenings of MCTSs. Keywords: C[O.sub.2] laser; rapid prototyping; microneedle; multicellular tumor spheroids; microwells; hanging drops