Three-dimensional electron diffraction (3D ED)/microcrystal electron diffraction (MicroED) techniques are gaining in popularity. However, the data processing often does not fit existing graphical user interface softwa...
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Three-dimensional electron diffraction (3D ED)/microcrystal electron diffraction (MicroED) techniques are gaining in popularity. However, the data processing often does not fit existing graphical user interface software, instead requiring the use of the terminal or scripting. Scipion-ED, described in this article, provides a graphical user interface and extendable framework for processing of 3D ED/MicroED data. An illustrative project is described, in which multiple 3D ED/MicroED data sets collected on tetragonal lysozyme were processed with DIALS through the Scipion-ED interface. The ability to resolve unmodelled features in the electrostatic potential map was compared between three strategies for merging data sets.
To meet the challenges in resolving the complex morphologies of emergent nanoparticles, a program with a user-friendly graphical user interface has been developed for calculating small-angle scattering curves from cus...
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To meet the challenges in resolving the complex morphologies of emergent nanoparticles, a program with a user-friendly graphical user interface has been developed for calculating small-angle scattering curves from custom shapes. The software allows STL-format 3D models, models defined by mathematical functions or combinations of the two as initial input. As a transitional stage, lattice models are generated and the orientation-averaged small-angle scattering data can be calculated using typical spherical harmonics expansion. The validity of the protocol is verified by demonstration models with Protein Data Bank structures and known scattering functions. The software is applied to successfully calculate the scattering curves of a porous spherical shell model where traditional mathematical derivation fails.
Intellectual property offices are having difficulty drawing the line between patentable and unpatentable subject-matter, especially when it comes to computer-related inventions. The difficulty lies in the balance betw...
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Intellectual property offices are having difficulty drawing the line between patentable and unpatentable subject-matter, especially when it comes to computer-related inventions. The difficulty lies in the balance between determining whether an "invention" is merely an abstract idea and/or a mathematical algorithm or has "something extra" which makes it worthy of patent protection. To incentivize innovation, an appropriate test for patentable subject-matter must be clearly laid out. This paper sets out to examine how the test for patentable subject-matter has evolved in the US and Canada. We focus our discussion on a recent decision that promises to be a significant development for patentable subject-matter in Canada and provide our preliminary thoughts on the decision.
The design of mechanical systems is a complex process that is often associated with significant time and budget overruns. Model-Based Systems Engineering (MBSE) has emerged as a way to mitigate these issues. However, ...
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ISBN:
(数字)9781624107047
ISBN:
(纸本)9781624107047
The design of mechanical systems is a complex process that is often associated with significant time and budget overruns. Model-Based Systems Engineering (MBSE) has emerged as a way to mitigate these issues. However, MBSE alone lacks the ability to simulate, analyze and design mechanical systems. Multidisciplinary Design Optimization (MDO) treats the parameters of the mechanical system as design variables and uses numerical optimization methods to find the parameters that optimize performance metrics while meeting constraints. However, it lacks the systematic traceability that MBSE offers. This paper proposes a methodology that builds on the Requirements Engineering, Functional Design, Logical Design, and Physical Design (RFLP) approach to integrate MBSE and MDO and overcome each other's limitations. The recently proposed Process RFLP is used to aid in the development, enumeration, and selection of design activities involving simulation and MDO. Guidelines for the implementation of RFLP are formulated and presented. The approach is demonstrated through a test case involving the design of a single-aisle transport category aircraft. Compliance with aircraft requirements is verified, and a change in requirements case is presented. The long-term goal is to automate the methodology to enable MBSE to drive the formulation and execution of MDO.
This paper describes both the low and high fidelity methods used in implementation of machine learning based optimization techniques for aerodynamic shape optimization of hydrogen powered commercial aircraft. Using vo...
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ISBN:
(数字)9781624107047
ISBN:
(纸本)9781624107047
This paper describes both the low and high fidelity methods used in implementation of machine learning based optimization techniques for aerodynamic shape optimization of hydrogen powered commercial aircraft. Using vortex lattice method based aerodynamic performance estimations in conjunction with empirical solvers used to estimate an arbitrarily generated aircraft's overall structural weight and drag, a Bayesian optimization algorithm is applied to optimize the wing to maximize the aircraft's overall range. This method was applied to a test case of the Boeing 737-800 where it was seen to predict the planform shape of the real world wing with a high degree of accuracy. This methodology is then applied to the design of transonic supercritical airfoils in which the airfoil is parameterized and optimized to reduce drag at a specified lift coefficient. The resultant airfoils are seen to closely resemble modern supercritical airfoils and reduce the drag significantly. Lastly a method of airfoil surrogate modelling using convolutional neural networks to predict aerodynamic performance of airfoils at a fraction of the computational cost is examined. This method is seen to provide highly accurate estimates for the drag coefficient of airfoils, however is seen to fall short of being able to fully optimize the airfoils. Ultimately the previously described methodologies are all used in conjunction to create a computer program which is able to fully optimize the geometry and airfoil distribution of a wing with high degree of accuracy at the maximum possible computational efficiency.
In this study, a new approach is developed to solve the mistuned bladed disk partial differential equation (PDE) with arbitrary spatial nonuniformities, and obtain natural frequencies, mode shapes, and steady-state re...
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In this study, a new approach is developed to solve the mistuned bladed disk partial differential equation (PDE) with arbitrary spatial nonuniformities, and obtain natural frequencies, mode shapes, and steady-state response. The method is based on the novel approach developed by the author to compute natural frequencies and mode shapes of a one-dimensional continuous structure with arbitrary nonuniformities and discontinuities. This method is based on the state transition matrix and has also been applied to a circular membrane with radial non-uniformities, and resulting mode shapes are used to develop a reduced-order model for a circular membrane with both radial and circumferential nonuniformities.
作者：
Knyazkov, DmitriRAS
Ishlinsky Inst Problems Mech Lab Control Mech Syst Prospekt Vernadskogo 101-1 Moscow 119526 Russia
The paper considers simulation of microwave remote sensing of the ocean. The direct and inverse problems of diffraction of a plane electromagnetic wave on a periodic inhomogeneous layer of finite thickness are conside...
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The paper considers simulation of microwave remote sensing of the ocean. The direct and inverse problems of diffraction of a plane electromagnetic wave on a periodic inhomogeneous layer of finite thickness are considered. The computer program is developed, that allows to model the process of active and passive radiometry of the free surface or of the near-surface layer of the ocean. The program is validated by comparison with the analytical result for the case of a periodically repeating planar layered structure. High accuracy of calculations is shown. The results of a number of calculations for the needs of passive and active radiometry of the surface and of the medium consisting of layers with sinusoidal boundaries are presented. Copyright (C) 2022 The Authors.
Neutron diffraction is a crucial non-destructive technique for obtaining statistical information on the bulk properties of engineering materials. The program 3DStrainOrientationCalculator ( 3DSOC ) is an innovative an...
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Neutron diffraction is a crucial non-destructive technique for obtaining statistical information on the bulk properties of engineering materials. The program 3DStrainOrientationCalculator ( 3DSOC ) is an innovative analytical tool designed to extract substructure information, including lattice strain and subgrain orientation, from single crystals (SCs) using monochromatic neutron diffractometer data. By separating subgrain diffraction via rocking curve analysis and employing 2D curve fitting on original diffraction data, 3DSOC accurately determines the diffraction intensity of individual subgrains while minimizing the impact of scanning step size on the final fitting results. It reduces the standard deviation of the fitting result's statistical error from the order of 10 −3 to around 10 −5 . Additionally, 3DSOC extends its capabilities to the analysis of dual-phase SCs, where the lattice parameters of both phases are maintained with an accuracy of 10 −4 nm, comparable to conventional methods. This study applies 3DSOC to SiC SCs and Ni-based SC superalloys, measured using two different diffractometers, and discusses the resulting improvements.
Studying the relationship between sequences and their corresponding three-dimensional structure assists structural biologists in solving the protein-folding problem. Despite several experimental and in-silico approach...
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Studying the relationship between sequences and their corresponding three-dimensional structure assists structural biologists in solving the protein-folding problem. Despite several experimental and in-silico approaches, still understanding or decoding the three-dimensional structures from the sequence remains a mystery. In such cases, the accuracy of the structure prediction plays an indispensable role. To address this issue, an updated web server (CSSP-2.0) has been created to improve the accuracy of our previous version of CSSP by deploying the existing algorithms. It uses input as probabilities and predicts the consensus for the secondary structure as a highly accurate three-state Q3 (helix, strand, and coil). This prediction is achieved using six recent top-performing methods: MUFOLD-SS, RaptorX, PSSpred v4, PSIPRED, JPred v4, and Porter 5.0. CSSP-2.0 validation includes datasets involving various protein classes from the PDB, CullPDB, and AlphaFold databases. Our results indicate a significant improvement in the accuracy of the consensus Q3 prediction. Using CSSP2.0, crystallographers can sort out the stable regular secondary structures from the entire complex structure, which would aid in inferring the functional annotation of hypothetical proteins. The web server is freely available at https://***/cgi-bin/cssp-2/
A model of thermodynamics of a reacting mixture of rarefied gases and a suspension of condensed species is developed by using statistical physics methods. An NVT ensemble is considered for determining the detailed equ...
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A model of thermodynamics of a reacting mixture of rarefied gases and a suspension of condensed species is developed by using statistical physics methods. An NVT ensemble is considered for determining the detailed equilibrium chemical composition, and the minimum of the free energy of the mixture of possible species is found numerically. Tabular data for the species are used for determining the enthalpy and free energy of chemical compounds. An algorithm that allows the Chapman-Jouguet detonation parameters to be determined for a wide range of combustible mixtures is developed. The model is tested through comparisons of the predicted and experimental detonation velocities. Good agreement for mixtures with oxygen excess is demonstrated. For compositions with the formation of a significant amount of condensed carbon, the predicted and experimental detonation velocities agree reasonably well.
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