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Keywords: ab initio; electronic structure; FANCI; method development; Python Abstract Fanpy is a free and open-source Python library for developing and testing multideterminant wavefunctions and related ab initio methods in electronic structure theory. The main use of Fanpy is to quickly prototype new methods by making it easier to convert the mathematical formulation of a new wavefunction ansätze to a working implementation. Fanpy is designed based on our recently introduced Flexible Ansatz for N-electron Configuration Interaction (FANCI) framework, where multideterminant wavefunctions are represented by their overlaps with Slater determinants of orthonormal spin-orbitals. In the simplest case, a new wavefunction ansatz can be implemented by simply writing a function for evaluating its overlap with an arbitrary Slater determinant. Fanpy is modular in both implementation and theory: the wavefunction model, the system's Hamiltonian, and the choice of objective function are all independent modules. This modular structure makes it easy for users to mix and match different methods and for developers to quickly explore new ideas. Fanpy is written purely in Python with standard dependencies, making it accessible for various operating systems. In addition, it adheres to principles of modern software development, including comprehensive documentation, extensive testing, quality assurance, and continuous integration and delivery protocols. This article is considered to be the official release notes for the Fanpy library. Article Note: Funding information Canada Research Chairs; Natural Sciences and Engineering Research Council of Canada; CANARIE; Compute Canada; Research Board of Ghent University; University of Florida Byline: Taewon D. Kim, M. Richer, Gabriela Sánchez-Díaz, Ramón Alain Miranda-Quintana, Toon Verstraelen, Farnaz Heidar-Zadeh, Paul W. Ayers

Algorithm, Sensors -- Analysis, Wireless sensor networks -- Analysis, and Algorithms -- Analysis

Keywords Tissue P System; Wireless Sensor Network; Multi-Objective problem; Task Assignment; Decision Support System; Parallel computing; Sustainable computing Abstract The contemporary wireless sensor applications employ a Heterogeneous Wireless Sensor Network (HeWSN) to achieve its multi-objective missions. Modern wireless nodes constituting the HeWSN are more versatile in terms of its capabilities, functionalities, and applications. Assigning tasks in a dynamic HeWSN environment are challenging due to its inherent heterogeneous properties and capabilities. The investigation of existing task assignment algorithms reveals (i) the majority of the existing task assignment algorithms were designed for the homogeneous environment, (ii) most of the nature-inspired algorithms were built for centralized architecture. Scheduling tasks by existing task assignment algorithms lead to underutilization of resources as well as to the rapid depletion of network resources. To this end, a novel, distributed, heterogeneous task assignment algorithm adhering the modern sensors capabilities, functionalities and sensor application to attain sustainable computing is required. Based on the investigation, Tissue P-System inspired task assignment algorithm for the distributed heterogeneous WSN has been modelled. The experimental analyses of the proposed method have been self-evaluated as well as compared with the corresponding recent benchmark algorithms under various conditions and its performance metrics are analysed. Author Affiliation: Karunya Institute of Technology & Sciences, Coimbatore, Tamil Nadu 641 114, India * Corresponding author. Article History: Received 18 November 2019; Revised 11 June 2020; Accepted 21 June 2020 (footnote) Peer review under responsibility of King Saud University. Byline: Titus Issac [titusissac@gmail.com] (*), Salaja Silas, Elijah Blessing Rajsingh

Implant dentures -- Methods, Implant dentures -- Usage, Rapid prototyping -- Methods, and Rapid prototyping -- Usage

To purchase or authenticate to the full-text of this article, please visit this link: http://onlinelibrary.wiley.com/doi/10.1002/rcs.1895/abstract Byline: Mohamed Farid Shehab, Nabila Mohammed Abdel Hamid, Nevien Abdullatif Askar, Ahmed Mokhtar Elmardenly Keywords: CAD-CAM, electron beam melting; immediate mandibular reconstruction; patient-specific titanium mesh; rapid prototyping Abstract Background Immediate mandibular reconstruction was performed using a patient-specific titanium mesh tray fabricated by electron beam melting (EBM) /rapid prototyping techniques. Methods Patient-specific titanium trays were virtually designed and fabricated using EBM technology/rapid prototyping for patients requiring mandibular resection and immediate reconstruction using an iliac crest bone graft. Dental implants were placed in the grafted sites and the patients received prosthetic rehabilitation with a follow-up of one year. Clinical data, postoperative bone formation and complications were evaluated. Results A symmetric appearance of facial contours was achieved. The titanium tray incorporated the particulate iliac crest bone graft that provided significant bone formation (mean 18.97 [+ or -] 1.45 mm) and predictable results. Stability of the dental implants was achieved. Conclusion The patient-specific titanium meshes and immediate particulate autogenous bone graft showed satisfactory clinical and surgical results in improving patients' quality of life and decreasing the overall treatment time with adequate functional rehabilitation.

3D printing -- Usage -- Models, Computer-aided design -- Models -- Usage, Mechanical engineering -- Usage, and Vibration -- Models -- Usage

Keywords vibrations; additive manufactoring; computer modeling; rapid prototyping Abstract The emerging concept of mechanical meta-materials has gained increasing attention in recent years, partly due to advances in additive manufacturing techniques (additive manufacturing, 3D printing) that have allowed the fabrication of materials with arbitrarily complex micro / nanostructures. The designed geometry of these structures gives rise to unprecedented or rare mechanical properties that can used to create advanced elements with new, unprecedented functions. This paper presents the method of prototyping a vibro-isolator made of a material that has the properties of storing and disposing of mechanical vibration energy and that can freely be shaped by modern manufacturing techniques. An example of a vibration isolator of the proprietary concept analyzed, using the concept of stepped and adding elements. The method is based on the use of two main tools. Mechanical properties verified by analyzing the frequency and mode of free vibrations of the prototype using the finite element method. The same CAD model of the vibro-isolator prototype produced by 3D printing. The paper presents one of the production techniques, which is 3D printing in SLS (Selective Laser Sintering) technology, and the SolidWorks and Comsol Multhiphysics software used in the CAD / CAE prototyping method. Author Affiliation: (a) Faculty of Mechanical Engineering,Koszalin University of Technology, Koszalin 75-453, Poland Byline: Remigiusz Knitter (a), Andrzej Blazejewski (a), Tomasz Królikowski [tomasz.krolikowski@tu.koszalin.pl] (a)

Algorithms -- Analysis and Algorithm

Teaching -- Usage, Teaching -- Methods, and Teaching -- Study and teaching

Given the ubiquity of interfaces on computing devices, it is essential for future Information Systems (IS) professionals to understand the ramifications of good user interface (UI) design. This article provides instructions on how to efficiently and effectively teach IS students about "fit," a Human-Computer Interaction (HCI) concept, through a paper prototyping activity. Although easy to explain, the concept of "fit" can be difficult to understand without repeated practice. Practically, designing "fit" into UIs can be cost-prohibitive because working prototypes are often beyond students' technical skillset. Accordingly, based on principles of active learning, we show how to use paper prototyping to demonstrate "fit" in a hands-on class exercise. We provide detailed stepby-step instructions to plan, setup, and present the exercise to guide students through the process of "fit" in UI design. As a result of this activity, students are better able to employ both theoretical and practical applications of "fit" in UI design and implementation. This exercise is applicable in any course that includes UI design, such as principles of HCI, systems analysis and design, software engineering, and project management. Keywords: Human-computer interaction (HCI), Paper prototyping, Active learning, Constructionism, Teaching tip
1. INTRODUCTION With computing devices peppering nearly every aspect of our lives, how people interact with these technologies is critically important to all computing fields. In fact, failure to properly [...]

Drilling and boring -- Models, Control systems -- Models, Vibration -- Models, and Oil well drilling rigs -- Models

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at mature drilling rig retrofitting. The rotary drive is equipped with an active damping speed control system featuring a proportional-integral speed controller readily available within modern controlled electrical drives, extended with drill-string back-spinning prevention scheme for the case of stuck tool. The draw-works hoist system features a tool normal force (Weight-on-Bit) controller with tool longitudinal speed (Rate-of-Penetration) limiting functionality. The design of proposed control systems has been based on suitable control-oriented process models and damping optimum criterion which guarantees a desired level of closed-loop system damping. The proposed drilling control systems have been verified on a downscaled laboratory experimental setup, which represents a necessary pre-requirement before these systems are tested in the field. Keywords: active damping; draw-work; laboratory setup; petroleum drilling; proportional-integral controller; retrofitting; top-drive; torsional vibrations
1 INTRODUCTION Diminishing petroleum reserves and related increase in its prices [1] generally stimulate the discovery of new reserves [2], and implementation of advanced drilling technologies [3], especially those aimed [...]

Algorithm, Electric filters -- Usage, Electric filters -- Analysis, Electric filters -- Models, Algorithms -- Analysis, and Algorithms -- Models

Sensors

Keywords Raspberry Pi; BeagleBone; Sharks Cove; Waspmote Abstract Arduino, an open-source electronics platform, has become the go-to option for anyone working on interactive hardware and software projects. An Arduino board (such as the Uno) connected to a breadboard with plugins such as inputs, sensors, lights, and displays can be controlled by a code written in the Arduino development environment. How to achieve this is by prototyping with Arduino. Prototyping with Arduino has grown in popularity with the increased use of the Arduino platform. Prototyping with Arduino, however, is not an easy task for nonprogrammers with interest in the field. With increased public interest in the field will come a need for accessible information. This paper presents a methodical literature review intended to intensively analyze and compare existing primary studies on prototyping with Arduino. We found about 130 of such studies, all peer-reviewed and published within the last 15 years, including these years (2015--2020). These studies were tediously and carefully chosen through a three-step process. In this paper, a cautious analysis of selected studies was followed by a clear description of the methods applied. The methods were categorized according to the success rate of the studied prototypes. Results obtained can be used in researches on the best technique to adopt while prototyping with Arduino. They can also be used in electronics researches and by individuals who wish to obtain a guide on prototyping with Arduino despite lacking grounded knowledge of the subject matter. Author Affiliation: (a) School of Computer Science & Engineering, VIT-AP University, Beside AP Secretariat, Near Vijayawada, Andhra Pradesh, India (b) School of Electronics Engineering, VIT-AP University, Beside AP Secretariat, Near Vijayawada, Andhra Pradesh, India * Corresponding author. Article History: Received 22 September 2020; Accepted 13 January 2021 Byline: Hari Kishan Kondaveeti [kishan.kondaveeti@vitap.ac.in] (a,*), Nandeesh Kumar Kumaravelu (b), Sunny Dayal Vanambathina (b), Sudha Ellison Mathe (b), Suseela Vappangi (b)

Satellite communications, Antennas (Electronics) -- Design and construction, Waveguides -- Design and construction, Sintering, 3D printing, Satellite communications, and Computer-aided design

Keywords: additive manufacturing; fused filament fabrication; phase shifter; reconfigurable; selective laser sintering; waveguide Abstract This work presents the design and manufacturing of a K-band reconfigurable phase shifter completely implemented in waveguide technology for reduced insertion loss, good matching, and large phase shifting range. The device is based on the combination of a short slot coupler and two tunable reactive loads implemented as a section of short-circuited waveguide where an adjustable metallic post is inserted. Three prototypes of this design have been manufactured using different techniques (conventional computer numerical control machining, a low-cost fused filament fabrication technique and direct metal laser sintering) in order to assess its performance for different applications. The prototypes have been characterized experimentally and the achieved results are evaluated and compared. The proposed phase shifter, since it is fully developed in waveguide technology, eliminates the need of adding transitions to planar structures in order to integrate lumped components like pin diodes or varactors. Therefore, this device has a great potential in high-power beam steering phased arrays. Biographical information: Lucas Polo-Lopez received the BSc and MSc degrees in Telecommunication Engineering from the Universidad Autonoma de Madrid, Madrid, Spain in 2014 and 2016, respectively. Since 2015 he has been with the Radiofrequency Circuits, Antennas and Systems (RFCAS) group of this same university, where he works toward the PhD degree. His current research interests include the computer-aided design of horn antennas and passive waveguide devices, as well as the application of additive manufacturing techniques to the construction of waveguide devices. Jose L. Masa-Campos received the Master degree in 1999 and the PhD Degree in 2006, from the Universidad Politecnica de Madrid, Spain. From 1999 to 2003 he developed his professional activity in the R&D department of the company RYMSA with the design of base station antennas for mobile communications and satellite antennas. From 2002 to 2003 he directed the R&D department of RYMSA. From 2003 to 2007, he worked as Researcher for Universidad Politecnica de Madrid, and in 2005 he joined to Universidad Autonoma de Madrid as Associate Professor in the Radiofrequency Circuits, Antennas and Systems (RFCAS) group. His main current research interests are in active and passive planar array antennas. Jorge A. Ruiz-Cruz received the Ingeniero de Telecomunicacion degree and the PhD degree from the Universidad Politecnica de Madrid, Madrid, Spain, in 1999 and 2005, respectively. Since 2006, he has been with the Universidad Autonoma de Madrid, Madrid, where he became an Associate Professor in 2009. His current research interests include the computer-aided design of microwave passive devices and circuits (filters, multiplexers, and orthomodes). Byline: Lucas Polo-Lopez,Jose L. Masa-Campos,Jorge A. Ruiz-Cruz