Successes and Predictions of A Pseudopotential Approach in Anion-Mixed Nitrides

2001 ◽  
Vol 692 ◽  
Author(s):  
L. Bellaiche ◽  
A. Al-Yacoub ◽  
N. A. Modine ◽  
E. D. Jones

AbstractThe construction and the parameters of a new-strain dependent empirical pseudopotentials method are described and provided, respectively. This method is shown to reproduce with a very high accuracy some observed unusual properties in various complex anion-mixed nitride alloys. This method is also used to predict and understand anomalous effects that remain to be experimentally discovered in Ga1−yInyAs1−xNx quaternaries and GaAs0.5−xP0.5−xN2x solid solutions.

1996 ◽  
Vol 176 ◽  
pp. 53-60 ◽  
Author(s):  
J.-F. Donati

In this paper, I will review the capabilities of magnetic imaging (also called Zeeman-Doppler imaging) to reconstruct spot distributions of surface fields from sets of rotationnally modulated Zeeman signatures in circularly polarised spectral lines. I will then outline a new method to measure small amplitude magnetic signals (typically 0.1% for cool active stars) with very high accuracy. Finally, I will present and comment new magnetic images reconstructed from data collected in 1993 December at the Anglo-Australian Telescope (AAT).


2014 ◽  
Vol 984-985 ◽  
pp. 67-72 ◽  
Author(s):  
R. Clifford Benjamin Raj ◽  
B. Anand Ronald ◽  
A. Velayudham ◽  
Prasmit Kumar Nayak

Deep-hole drilling is a process in which the hole length will be very high when compared to diameter of the drill hole (i.e. length to diameter ratio will be greater than 5). Drilling a deep hole with very high accuracy is difficult process. The current project is about the production of deep hole with the aim to produce a chip which is not a continuous chip and also not a powdery chip. These conditions can be attained by varying the spindle speed and the tool feed rate.


2001 ◽  
Vol 35 (4) ◽  
pp. 33-45 ◽  
Author(s):  
Peter Hogarth

Between 23rd and 25th July 2001 GeoSwath, a high specification shallow water wide swath bathymetry system, was used to survey the entire Portsmouth NH Harbor area. This paper deals with the results of this survey, illustrating the potential for significant reductions in the high costs, which have prevented widespread proliferation of Swath Bathymetry systems to date. Data, including a complete DTM gridded to 1 m resolution, will be presented and discussed in detail. These results show that the system is very easy to set up and use, requires greatly reduced boat and processing time, whilst offering high accuracy and very high coverage and resolution when used in a real-world survey of a dynamic harbor environment.


2008 ◽  
Vol 134 (4) ◽  
pp. A-362
Author(s):  
Emilia Sugai ◽  
María Laura Moreno ◽  
Hui Jer Hwang ◽  
Adriana Crivelli ◽  
Fabio Nachman ◽  
...  

1975 ◽  
Vol 39 (2) ◽  
pp. 327-330
Author(s):  
C. R. Wyss

By implementing analog computer techniques using digital circuits, an instantaneous rate meter was built with approximately 100 times the accuracy of commercially available rate meters. The circuit is accurate to within +/- 0.2 events/min over a range of rates of 0.2–900 epm. Modifications can be made to provide a digital display of rate. The circuit design techniques used in developing the rate meter may be used to generate a wide variety of functions of time with very high accuracy.


Author(s):  
Tadeusz Sobczyk ◽  
Michał Radzik ◽  
Natalia Radwan-Pragłowska

Purpose To identify the properties of novel discrete differential operators of the first- and the second-order for periodic and two-periodic time functions. Design/methodology/approach The development of relations between the values of first and second derivatives of periodic and two-periodic functions, as well as the values of the functions themselves for a set of time instants. Numerical tests of discrete operators for selected periodic and two-periodic functions. Findings Novel discrete differential operators for periodic and two-periodic time functions determining their first and the second derivatives at very high accuracy basing on relatively low number of points per highest harmonic. Research limitations/implications Reduce the complexity of creation difference equations for ordinary non-linear differential equations used to find periodic or two-periodic solutions, when they exist. Practical implications Application to steady-state analysis of non-linear dynamic systems for solutions predicted as periodic or two-periodic in time. Originality/value Identify novel discrete differential operators for periodic and two-periodic time functions engaging a large set of time instants that determine the first and second derivatives with very high accuracy.


1999 ◽  
Author(s):  
L. P. Li ◽  
M. D. Buschmann ◽  
A. Shirazi-Adl

Abstract Articular cartilage is a highly nonhomogeneous, anisotropic and multiphase biomaterial consisting of mainly collagen fibrils, proteoglycans and water. Noncalcified cartilage is morphologically divided into three zones along the depth, i.e. superficial, transitional and radial zones. The thickness, density and alignment of collagen fibrils vary from the superficial zone, where fibrils are oriented parallel to the articular surface, to the radial zone where fibrils are perpendicular to the boundary between bone, and cartilage. The concentration of proteoglycans increases with the depth from the cartilage surface. These regional differences have significant implications to the mechanical function of joints, which is to be explored theoretically in the present work by considering inhomogeneity along the cartilage depth. A nonlinear fibril reinforced poroelastic model is employed as per Li et al. (1999) in which the collagen fibrils were modeled as a distinct constituent whose tensile stiffness was taken to be very high and be strain dependent but whose compressive stiffness was neglected.


Author(s):  
Shuichi Fukuda ◽  
Daisuke Suzuki

Abstract We developed a new CAD tool with special attention paid to rapid prototyping. Most of the present 3-D CAD systems treat geometry with very high accuracy but it is not easy to define or modify geometry as we do in the earlier stages of design. The present CAD systems, we believe, are more oritented toward the detailed design and manufacturing of the final product. As rapid prototyping itself is intended for the earlier stages of design, such a CAD system that permitts more easy or rough definition and modification of geometry is really desired. Most of the rapid prototyping systems generate 3-D geometry by piling up the 2-D sections layer by layer. So, if we develop such a layer-based CAD system, then we could more easily tranfer CAD data to the prototyping system. Such an idea was very old, but the traditional ones cannot manipulate geometry with much ease. What we aimed here is to develop a system that a designer can manipuate geometry as freely as he or she wishes. Thus, our system serves as a preprocessor to the present 3-D CAD systems. We are developing another system which permits to generate 3-D geometry as freely as if we are drawing it using a pen, based on the technology of 3-D measurement device. Couled with this system, the system we are proposing here is expected to tranfer such a 3-D geometry data very rapidly and easily to the prototyping equipment and also can interactively modify thus defined geometry data.


Author(s):  
Fang Chu ◽  
Lipo Wang

Accurate diagnosis of cancers is of great importance for doctors to choose a proper treatment. Furthermore, it also plays a key role in the searching for the pathology of cancers and drug discovery. Recently, this problem attracts great attention in the context of microarray technology. Here, we apply radial basis function (RBF) neural networks to this pattern recognition problem. Our experimental results in some well-known microarray data sets indicate that our method can obtain very high accuracy with a small number of genes.


2019 ◽  
Vol 13 (3) ◽  
pp. 180-183
Author(s):  
Anđelko Crnoja ◽  
Željko Kos ◽  
Oleg Popov

During the last two decades, technological development has led to an extreme increase in transport and connected industries. This has significantly increased the production of automobile tires, which have their life span after which they go to waste. It is therefore necessary to extricate new products from recycled raw materials. For a product to be created, it is necessary, especially in civil engineering, to examine and determine all the properties of this material (pressure, traction, stress resistance, etc.). The results obtained by the research in this paper are mathematically processed by applying a logarithmic model. The aim of this process is to predict stress deformation in terms of tensile force. The model obtained is significant with accuracy of 87.21% and has a very high accuracy of the deformation estimation in relation to the applied stress. Independent variables were granulometric composition, binder (glue) and specific mass.


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