scholarly journals Method of nonlinear code multiplexing of a multiphase group sequence.

2021 ◽  
Author(s):  
O.Yu. Berdyshev ◽  
Keyword(s):  
Complex Space ◽  
Communication Channels ◽  
Phase Information ◽  
Constant Power ◽  
Definite Integrals ◽  
Phase Group ◽  
Binary Group ◽  
Analytical Expressions ◽  
Orthogonal Sequences

This paper presents the generalization of the method of nonlinear code multiplexing of a binary group sequence is considered for the r – phase group sequences. A transition to a complex space, as well as using definite integrals, and conversion of the Cartesian chart while turning at a set angle are used to form the r – phase group sequence with a constant power from the multiphase summary group sequence, which consist of the sum of the r – phase information orthogonal sequences. As a result, the multiphase summary group sequences are mapped to the r-phase group sequences with constant power, which contain the information orthogonal r-phase sequences which are a part of these summary group sequences. Analytical expressions of the r – phase group sequences with constant power are obtained for even values of r. If the r is 4 the final formulas of group sequences with the constant power at the odd quantity of the information orthogonal sequences in the summary group sequences is obtained. The method of nonlinear code multiplexing of a multiphase group sequence considered in this paper, can be applied to increase capacity of communication channels with nonlinear code multiplexing.

Resistive Heating of a Shape Memory Composite: Analytical, Numerical and Experimental Study

2021 ◽  
Author(s):  
Clara Andrea Pereira Sánchez ◽  
Maxime Houbben ◽  
Jean-François Fagnard ◽  
Philippe Laurent ◽  
Christine Jerome ◽  
...  
Keyword(s):  
Steady State ◽  
Shape Memory ◽  
Temperature Dependence ◽  
Electric Current ◽  
Multiwall Carbon Nanotubes ◽  
Resistive Heating ◽  
Constant Power ◽  
Thermo Electric ◽  
Steady State Temperature ◽  
Analytical Expressions

Abstract This work investigates in detail the Joule resistive heating phenomenon of electroactive Shape Memory Composites (SMC) when an electric current is injected at constant power. The SMC is a covalent poly(ε-caprolactone) network filled with 3 wt% of multiwall carbon nanotubes. The resistive heating of the SMC is studied by means of surface temperature measurements, analytical formulas and a coupled 3D thermo-electric numerical model. Analytical expressions are derived for the 2D temperature distribution within a parallelepipedic SMC, either with constant or linearly-dependent electrical resistivity. These analytical expressions can be used to investigate the influence of geometrical and material parameters in the steady-state temperature and its distribution across the sample. The results also allow one to identify the parameters that are crucial for predicting the temperature rise due to resistive heating: the temperature dependence of the resistivity has little effect on the steady-state temperature, whereas the thermal conductivity plays a significant role. The time-dependent temperature is shown to be related to the particular temperature dependence of heat capacity. Furthermore, the presence of external objects (clamps or grips) used during the shape memory cycle must be taken into consideration for a certain temperature to be reached since they result in a lower steady-state temperature and a slower resistive heating phenomenon. With the findings presented in this work, accurate resistive heating can be predicted for a SMC upon the injection of an electric current at constant power.

Two-dimensional β-phase group-VA binary compounds for versatile electronic and optical properties

2018 ◽  
Vol 6 (43) ◽  
pp. 11694-11700 ◽  
Author(s):  
Hui Zhang ◽  
Mingyang Chen
Keyword(s):  
Optical Properties ◽  
Carrier Mobility ◽  
Two Dimensional ◽  
Electronic And Optical Properties ◽  
Β Phase ◽  
Phase Group ◽  
Binary Group ◽  
Binary Compounds

Six 2D β-phase binary group-VA monolayers were explored with a maximum carrier mobility of 589.87 cm−2 V−1 s−1.

Electron holography of catalysts

1995 ◽  
Vol 53 ◽  
pp. 416-417
Author(s):  
A. K. Datye ◽  
D. S. Kalakkad ◽  
L. F. Allard ◽  
E. Völkl
Keyword(s):  
Heterogeneous Catalysts ◽  
High Surface ◽  
High Surface Area ◽  
Atomic Scale ◽  
Nano Particles ◽  
Phase Image ◽  
Electron Holography ◽  
Specimen Thickness ◽  
Phase Information ◽  
Particle Structure

The active phase in heterogeneous catalysts consists of nanometer-sized metal or oxide particles dispersed within the tortuous pore structure of a high surface area matrix. Such catalysts are extensively used for controlling emissions from automobile exhausts or in industrial processes such as the refining of crude oil to produce gasoline. The morphology of these nano-particles is of great interest to catalytic chemists since it affects the activity and selectivity for a class of reactions known as structure-sensitive reactions. In this paper, we describe some of the challenges in the study of heterogeneous catalysts, and provide examples of how electron holography can help in extracting details of particle structure and morphology on an atomic scale.Conventional high-resolution TEM imaging methods permit the image intensity to be recorded, but the phase information in the complex image wave is lost. However, it is the phase information which is sensitive at the atomic scale to changes in specimen thickness and composition, and thus analysis of the phase image can yield important information on morphological details at the nanometer level.

Layered and ion implantation specimens as possible reference materials for the electron-probe microanalysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1652-1653
Author(s):  
G. Remond ◽  
R.H. Packwood ◽  
C. Gilles ◽  
S. Chryssoulis
Keyword(s):  
Ion Implantation ◽  
Reference Materials ◽  
Analytical Techniques ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
X Ray ◽  
Spatially Resolved ◽  
Analytical Expressions ◽  
Original Approach ◽  
Depth Concentration

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

A Simple Real-Space Channelling Theory for Electron Diffraction and HREM

1990 ◽  
Vol 48 (1) ◽  
pp. 64-65
Author(s):  
D. Van Dyck
Keyword(s):  
High Resolution ◽  
Electron Diffraction ◽  
Direct Method ◽  
Real Space ◽  
Zone Axis ◽  
Phase Object ◽  
High Resolution Images ◽  
The Many ◽  
Analytical Expressions ◽  
Electron Wavefunction

The computation of the many beam dynamical electron diffraction amplitudes or high resolution images can only be done numerically by using rather sophisticated computer programs so that the physical insight in the diffraction progress is often lost. Furthermore, it is not likely that in this way the inverse problem can be solved exactly, i.e. to reconstruct the structure of the object from the knowledge of the wavefunction at its exit face, as is needed for a direct method [1]. For this purpose, analytical expressions for the electron wavefunction in real or reciprocal space are much more useful. However, the analytical expressions available at present are relatively poor approximations of the dynamical scattering which are only valid either for thin objects ((weak) phase object approximation, thick phase object approximation, kinematical theory) or when the number of beams is very limited (2 or 3). Both requirements are usually invalid for HREM of crystals. There is a need for an analytical expression of the dynamical electron wavefunction which applies for many beam diffraction in thicker crystals. It is well known that, when a crystal is viewed along a zone axis, i.e. parallel to the atom columns, the high resolution images often show a one-to-one correspondence with the configuration of columns provided the distance between the columns is large enough and the resolution of the instrument is sufficient. This is for instance the case in ordered alloys with a column structure [2,3]. From this, it can be suggested that, for a crystal viewed along a zone axis with sufficient separation between the columns, the wave function at the exit face does mainly depend on the projected structure, i.e. on the type of atom columns. Hence, the classical picture of electrons traversing the crystal as plane-like waves in the directions of the Bragg beams which historically stems from the X-ray diffraction picture, is in fact misleading.

Abstract #1103: Comprehensive Diabetes Care Through Continuous Communication Channels to Patients with Diabetes

2017 ◽  
Vol 23 ◽  
pp. 290
Author(s):  
Vamsi Kolukula ◽  
Jayashree Gopal ◽  
Shantharam Duvuru ◽  
Kalpana Dash ◽  
Sanjiv Shah ◽  
...  
Keyword(s):  
Diabetes Care ◽  
Communication Channels ◽  
Patients With Diabetes

Study and design of dual stator permanent magnet machine with spoke-type configurations using phase-group concentrated-coil windings

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1381-1389
Author(s):  
Dezhi Chen ◽  
Chengwu Diao ◽  
Zhiyu Feng ◽  
Shichong Zhang ◽  
Wenliang Zhao
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Low Cost ◽  
Dynamic Performance ◽  
Torque Ripple ◽  
Permanent Magnet Machine ◽  
Torque Density ◽  
Phase Group ◽  
High Torque ◽  
Simulation Results

In this paper, a novel dual-stator permanent magnet machine (DsPmSynM) with low cost and high torque density is designed. The winding part of the DsPmSynM adopts phase-group concentrated-coil windings, and the permanent magnets are arranged by spoke-type. Firstly, the winding structure reduces the amount of copper at the end of the winding. Secondly, the electromagnetic torque ripple of DsPmSynM is suppressed by reducing the cogging torque. Furthermore, the dynamic performance of DsPmSynM is studied. Finally, the experimental results are compared with the simulation results.

No ‘Help to the Imagination’: Kate O'Brien and the Emergency

2018 ◽  
Vol 48 (1) ◽  
pp. 97-112
Author(s):  
Anna Teekell
Keyword(s):  
Complex Space ◽  
Coercive Power ◽  
Cultural Conservatism ◽  
Kate O'brien ◽  
The Individual ◽  
Love Triangle

Kate O'Brien's 1943 The Last of Summer has been read as the novelist's riposte to an insular island that stifled both her publishing (through censorship) and her imagination (through cultural conservatism). Set on the eve of the neutral ‘Emergency’, O'Brien's sixth novel actually depicts Ireland as a complex space of negotiation, simultaneously desirable and condemnable, that challenges, rather than stifles, the individual imagination. The Last of Summer is a love triangle and a battle of wits, pitching a stage actress, the French ingénue Angèle, against an accomplished domestic performer, her potential mother-in-law, Hannah Kernahan. In the end, it is Hannah who wields ‘neutrality’ – both Ireland's in the war and her pretended neutrality in family matters – as a form of coercive power.

KINEMATIC FEATURES OF THE LAPPING PROCESS AND DETERMINATION OF ITS BASIC PARAMETERS

2020 ◽  
Vol 7 (3) ◽  
pp. 23-28
Author(s):  
EZIZ SARVAN SHIRVAN ◽  
Keyword(s):  
Dynamic Properties ◽  
Cutting Speed ◽  
Equilibrium System ◽  
Technological Parameters ◽  
Kinematic Characteristics ◽  
Angular Velocities ◽  
Basic Parameters ◽  
Grinding Tool ◽  
Mathematical Relationships ◽  
Analytical Expressions

This paper discusses the kinematic characteristics of lapping process and the main parameters of the process. It was determined that the influencing degree of technological parameters to the forming surface and processes. It was projected the construction of the lapping head for processing of internal cylindrical surfaces, scheme of the lapping operation and graphic description of the forces influencing. The relationships between the axial, radial and tangential cutting forces and the effect of the combined force thereof are determined in order to ensure the necessary surface pressure. During the analysis geometric and mathematical relationships were obtained. The extracted analytical expressions can be realized by further experimental researches and can be used in engineering calculations of technological parameters of processing by lapping. Angular velocity, friction force, linear velocity, also the length of the tactile curve and the radius of the part can be considered the main kinematic and dynamic parameters of the process that the formation of the surface, also the course of the process depends on these parameters. Depending on the kinematic parameters, the wear nature of the tool changes and this changes the linear and angular velocities, which have a significant impact on the accuracy, quality and productivity of processing. When examining the technological capabilities of the process, the nature of the movement between the part and the grinding tool, also changes in cutting speed are often considered as a main factor. Analytical expressions were obtained to determine the main parameters of the process, taking into account the kinematic characteristics of the friction process. These expressions can be used in engineering calculations and allow to determine the optimal values of the processing mode. In order to obtain the required micrometric surface cleanliness and measurement accuracy, correlation relationships were established between the main parameters of the process, equations of the equilibrium system of shear forces were compiled and analytical expressions were obtained based on the analysis of kinematic and dynamic properties of the system.

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