Universal quantum computing based on magnetic domain wall qubits

Quantum computers allow to solve efficiently certain problems that are intractable for classical computers. For the realization of a quantum computer, a qubit design as the basic building block is a nontrivial starting point. We propose the utilization of nanoscale magnetic domain walls, which are stabilized by achiral energy, as the building blocks for a universal quantum computer made of ferromagnetic racetracks. In contrast to the domain walls stabilized by conventional Dzyaloshinskii-Moriya interactions, these achiral domain walls are bistable and show two degenerate chirality forms. When the domain wall is extremely small, it can be viewed as a quantum mechanical object and the two degenerate chiralities of the domain walls can be used to encode the qubit states $\lvert 0 \rangle$ and $\lvert 1 \rangle$. We show that the single-qubit quantum gates are regulated by magnetic and electric fields, while the Ising exchange coupling facilitates the two-qubit gates. The integration of these quantum gates allows for a universal quantum computation. Our findings demonstrate a promising approach for achieving quantum computing through spin textures that exist in ferromagnetic materials.Comment: Submitted on August 7t

Design of Reinforcement in Concrete Shells: a unified Approach

The problem of design/verification of reinforcement in concrete shells is reviewed. Methods of analysis are classified, and the elastic-plastic approach is described in detail in the general case of shells subjected to both bending and membrane action. The procedure is then reduced to membrane shells (applicable also to concrete walls) and to pure bending, as in the case of plates. The procedure, which is based on previous research,generally requires the use of a desk-top computer

ROLE OF 3D PRINTED GREEN WALLS IN HEALING ARCHITECTURE

Three-dimensional (3D) printing has become a fundamental issue in modern global technology, touching practically every element of modern human life.Three-dimensional (3D) printing (also known as additive manufacturing) is an advanced manufacturing technology that can autonomously manufacture complicated shape geometries from a 3D computer-aided design model without the use of equipment or fixtures.However, there is a friction between traditional designs and the rise of 3D printed technology when it comes to architectural healing approaches, and this adaptability is hurting human healing tactics that are dependent on the relationship between space and environment.Due to its capacity to create products in a wide range of materials rapidly and at a lower cost, additive manufacturing is having a significant impact on production in a variety of areas. Even though it encompasses a wide range of techniques and applications, additive manufacturing (AM) may be described as a system for converting solid model data from a computer-based model into a physical prototype by the incremental addition of material via layer superposition. Therefore, this research aims to examine the 3d printed green walls as new proposed design elements that can upgrade the natural healing architecture. To achieve this goal, the study begins with a literature review that includes scientific methodology based on principles that assist architects dealing with advanced tools in transforming their intentions from digital to analogue means as part of a controlled system intended to innovate design and construction principles of the use of 3D printed green walls. It will also assist in the quest for a concept design that confronts the regeneration of a new spatial delineation ideology

Computer simulation of temperature distribution during cooling of the thermally insulated room

This paper is devoted to modelling of temperature distribution and its time evolution in rooms with specific thermal insulation and heat transfer for different external conditions. The simulation results should help to design the room architecture and wall materials to reduce energy losses due to heating or cooling, and to increase the inside thermal comfort. For this purpose, a methodological procedure using real data processing in the COMSOL Multiphysics modelling environment and spatial visualization of temperature evolution is proposed. This paper describes a mathematical model for simulation of the temperature evolution inside a space with thermally insulated walls under selected outside conditions. Computer simulations are then used to assess the temperature distribution inside the room and the heat flow through the room walls. Results of the simulations are used for subsequent determination of the time needed for the desired decrease of air temperature inside the tested room during its cooling due to the low ambient temperature, which is related to the thermal stability of the building, specific heat capacity, and thickness of the thermal insulation. Under the studied conditions, the time to reach the temperature drops by 20 percent in a room with windows was from 1.4 to 1.8 times lower than that in the room without windows. The proposed methodology shows the flexibility of computer modelling in the design of insulated building systems. The mesh density testing was performed by comparing the air temperature evolution in the model of the selected mesh density and the model with its maximum value enabled by the size of computer memory. The maximum temperature deviation calculated for the mesh of the presented model was 0.57%. © 2018 by the authors.European Regional Development Fund under the project CEBIA-Tech Instrumentation [CZ.1.05/2.1.00/19.0376]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)

A mathematical model, with cost implications, for predicting temperatures in seed stores (ODNRI Bulletin No. 16)

Mathematical relationships are derived between climatic and design factors in seed stores using heat balance equations modified for tropical seed storage. A computer program has been written for the Hewlett Packard 9645 to make calculation easy; this incorporates data banks of the required parameters for common store building materials and for typical tropical climates. This program has been partially verified for grain in Sri Lanka using field data. Results from program case studies highlight the relative importance of different elements of warehouse design. For seed stores, the program employs viability equations to provide least-cost combinations of warehouse cladding and seed drying regimes under varying conditions of climate and building design. In a typical 1,000-tonne seed store use of aluminium roofing and concrete block walls instead of corrugated steel cladding can save over £12,000 a year, if both drying costs and annualized building costs are taken into account

Investigation of Modeling Strategies for Slender Lightly Reinforced Concrete Shear Walls

A large number of pre-1980’s non-ductile reinforced concrete (RC) structures in California utilizing RC shear walls to resist seismic lateral forces have been identified as deficient by industry practitioners. These non-ductile wall systems are typically lightly reinforced and lack adequate boundary element detailing. Analytical studies suggest these walls are susceptible to brittle, compression-controlled failure modes due to damage from concrete crushing and bar buckling. Furthermore, poor behavior of lightly reinforced concrete walls was observed in many recent earthquakes, for example in Chile (1985), New Zealand (2010/2011) and Mexico (2017). This has generated concern among engineers in high seismic regions around the globe. This research report provides a comprehensive analysis of academic and industry standards for analyzing lightly reinforced concrete shear walls with low axial loads and no boundary elements. First, a comparison of two recent experimental testing programs of non-ductile concrete shear walls by de Sevilla et. al. and Lu et. al. is provided. Next, simplified pushover analyses by Priestley and ASCE 41-17 are compared to the experimental testing results of the abovementioned test programs. After creating a basis for quick, simple predictions, the authors pursued defining the necessary modeling and analysis parameters to create a sophisticated computer simulated model in PERFORM-3D. A parametric study was utilized to create final calibrations on static pushover analyses and cyclic load analyses of each test wall. PERFORM-3D modeling recommendations are provided to give industry practitioners a starting point for modeling nonductile concrete walls. Finally, the report ends on small academic and industry studies that will support future design-build-test preparations for large-scale testing at Cal Poly San Luis Obispo