Pit Bistable optical devices: physical processes and practical applications

Abstract The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.

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Spatiotemporal functional modeling of postseismic deformations after the 2011 Tohoku-Oki earthquake

Earth Planets and Space ◽

10.1186/s40623-021-01568-0 ◽

2022 ◽

Vol 74 (1) ◽

Author(s):

Satoshi Fujiwara ◽

Mikio Tobita ◽

Shinzaburo Ozawa

Keyword(s):

Standard Deviation ◽

Statistical Data ◽

Functional Model ◽

Satellite System ◽

Physical Processes ◽

Linear Deformation ◽

Practical Applications ◽

Long Period ◽

Global Navigation Satellite ◽

Physical Phenomena

AbstractPostseismic deformations continue to occur for a long period after major earthquakes. Temporal changes in postseismic deformations can be approximated using simple functions. Since the 2011 Tohoku-Oki earthquake, operating global navigation satellite system stations have been continuously accumulating a remarkable amount of relevant data. To verify the functional model, we performed statistical data processing on postseismic deformations due to this earthquake and obtained their spatiotemporal distribution. Moreover, we approximated the postseismic deformations over a relatively wide area with a standard deviation of residuals of 1 cm for approximately 10 years using a combined functional model of two logarithmic and one exponential functions; however, the residuals from the functional model exhibited a marked deviation since 2015. Although the pattern of postseismic deformations remained unaltered after the earthquake, a change in the linear deformation occurred from 2015 to date. We reduced the overall standard deviation of the residuals of > 200 stations distributed over > 1000 km to < 0.4 cm in the horizontal component by enhancing the functional model to incorporate this linear deformation. Notably, time constants of the functions were similarly applicable for all stations and components. Furthermore, the spatial distribution of the coefficients of each time constant were nonrandom, and the distribution was spatially smooth, with minute changes in the short wavelengths in space. Thus, it is possible to obtain a gridded model in terms of a spatial function. The spatial distributions of short- and long-period components of the functional model and afterslip and viscoelastic relaxation calculated using the physical model were similar to each other, respectively. Each time function revealed a connotation regarding the physical processes, which provided an understanding of the physical phenomena involved in seismogenesis. The functional model can be used to practical applications, such as discerning small variations and modeling for precise positioning. Graphical Abstract

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Probabilistic Dynamics for Integrated Analysis of Accident Sequences considering Uncertain Events

Science and Technology of Nuclear Installations ◽

10.1155/2015/892502 ◽

2015 ◽

Vol 2015 ◽

pp. 1-18 ◽

Cited By ~ 2

Author(s):

Robertas Alzbutas

Keyword(s):

Uncertainty Analysis ◽

Probabilistic Methods ◽

Severe Accident ◽

Integrated Analysis ◽

Test Case ◽

Physical Processes ◽

Dynamic Reliability ◽

Practical Applications ◽

Deterministic Modelling ◽

Accident Sequences

The analytical/deterministic modelling and simulation/probabilistic methods are used separately as a rule in order to analyse the physical processes and random or uncertain events. However, in the currently used probabilistic safety assessment this is an issue. The lack of treatment of dynamic interactions between the physical processes on one hand and random events on the other hand causes the limited assessment. In general, there are a lot of mathematical modelling theories, which can be used separately or integrated in order to extend possibilities of modelling and analysis. The Theory of Probabilistic Dynamics (TPD) and its augmented version based on the concept of stimulus and delay are introduced for the dynamic reliability modelling and the simulation of accidents in hybrid (continuous-discrete) systems considering uncertain events. An approach of non-Markovian simulation and uncertainty analysis is discussed in order to adapt the Stimulus-Driven TPD for practical applications. The developed approach and related methods are used as a basis for a test case simulation in view of various methods applications for severe accident scenario simulation and uncertainty analysis. For this and for wider analysis of accident sequences the initial test case specification is then extended and discussed. Finally, it is concluded that enhancing the modelling of stimulated dynamics with uncertainty and sensitivity analysis allows the detailed simulation of complex system characteristics and representation of their uncertainty. The developed approach of accident modelling and analysis can be efficiently used to estimate the reliability of hybrid systems and at the same time to analyze and possibly decrease the uncertainty of this estimate.

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Coupled Superhydrophilic PMMA Film with Inverted Pyramid Microstructures for Antireflection and Antifogging Properties

Coatings ◽

10.3390/coatings11091107 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1107

Author(s):

Xiaoming Feng ◽

Guizhong Tian ◽

Shichao Niu ◽

Honggen Zhou

Keyword(s):

Sio2 Nanoparticles ◽

Optical Devices ◽

Silica Sol ◽

Pmma Film ◽

Transfer Printing ◽

Pmma Substrate ◽

Practical Applications ◽

Performance Loss ◽

Inverted Pyramid ◽

Pmma Surface

Transparent substrates with antifogging and antireflection ability are of extreme significance for optical devices, because they alleviate performance loss and maintenance costs. Here, we reported that a multifunctional film, with excellent mechanical properties, can be fabricated on the PMMA surface via the micro-transfer printing method. In particular, the synergistic effect of the inverted pyramid microstructure and SiO2 nanoparticles gives the film excellent antireflective, superhydrophilic and antifogging properties, and the silica sol firmly adheres to the PMMA substrate via the silane coupling agent, which exhibits an encouraging prospect of practical applications from lenses for personal and sports eyewear to transparent displays and sensors, etc.

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Downscaling, parameterization, decomposition, compression: a perspective from the multiresolution analysis

Advances in Geosciences ◽

10.5194/adgeo-23-65-2010 ◽

2010 ◽

Vol 23 ◽

pp. 65-71 ◽

Cited By ~ 3

Author(s):

J.-I. Yano

Keyword(s):

Multiresolution Analysis ◽

Convective Heating ◽

Subgrid Scale ◽

Atmospheric Models ◽

Physical Processes ◽

Model Simulations ◽

Practical Applications ◽

Fundamental Limitations ◽

New Type ◽

Representation Scheme

Abstract. Geophysical models in general, and atmospheric models more specifically, are always limited in spatial resolutions. Due to this limitation, we face with two different needs. The first is a need for knowing (or "downscaling") more spatial details (e.g., precipitation distribution) than having model simulations for practical applications, such as hydrological modelling. The second is a need for "parameterizing" the subgrid-scale physical processes in order to represent the feedbacks of these processes on to the resolved scales (e.g., the convective heating rate). The present article begins by remarking that it is essential to consider the downscaling and parametrization as an "inverse" of each other: downscaling seeks a detail of the subgrid-scale processes, then the parameterization seeks an integrated effect of the former into the resolved scales. A consideration on why those two closely-related operations are traditionally treated separately, gives insights of the fundamental limitations of the current downscalings and parameterizations. The multiresolution analysis (such as those based on wavelet) provides an important conceptual framework for developing a unified formulation for the downscaling and parameterization. In the vocabulary of multiresolution analysis, these two operations may be considered as types of decompression and compression. A new type of a subgrid-scale representation scheme, NAM-SCA (nonhydrostatic anelastic model with segmentally-constant approximation), is introduced under this framework.

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Models of Thermodynamic Properties of Prominences

International Astronomical Union Colloquium ◽

10.1017/s0252921100065799 ◽

1979 ◽

Vol 44 ◽

pp. 349-355

Author(s):

R.W. Milkey

Keyword(s):

Thermodynamic Properties ◽

Mass Transport ◽

Emission Spectrum ◽

Thermodynamic Parameters ◽

Working Group ◽

Physical Processes ◽

Theoretical Concepts ◽

Group 3 ◽

Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

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Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009292x ◽

1976 ◽

Vol 34 ◽

pp. 592-593

Author(s):

Ernest L. Hall ◽

J. B. Vander Sande

Keyword(s):

Mechanical Properties ◽

Single Crystal ◽

Dislocation Structure ◽

Room Temperature ◽

Elevated Temperatures ◽

Strain Curve ◽

Optical Devices ◽

Semiconductor Compound ◽

Wide Range ◽

Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

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Ion Beam Induced Interfacial Reactions in Molybdenum Thin Films on Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097466 ◽

1981 ◽

Vol 39 ◽

pp. 162-163

Author(s):

L. J. Chen ◽

L. S. Hung ◽

J. W. Mayer

Keyword(s):

Ion Beam ◽

Chemical Vapor ◽

Interfacial Reactions ◽

Practical Applications ◽

Microelectronic Devices ◽

Recent Emergence ◽

Chemical Vapor Deposited ◽

Atomic Mixing ◽

Silicon Interface ◽

Kinetics Of

When an energetic ion penetrates through an interface between a thin film (of species A) and a substrate (of species B), ion induced atomic mixing may result in an intermixed region (which contains A and B) near the interface. Most ion beam mixing experiments have been directed toward metal-silicon systems, silicide phases are generally obtained, and they are the same as those formed by thermal treatment.Recent emergence of silicide compound as contact material in silicon microelectronic devices is mainly due to the superiority of the silicide-silicon interface in terms of uniformity and thermal stability. It is of great interest to understand the kinetics of the interfacial reactions to provide insights into the nature of ion beam-solid interactions as well as to explore its practical applications in device technology.About 500 Å thick molybdenum was chemical vapor deposited in hydrogen ambient on (001) n-type silicon wafer with substrate temperature maintained at 650-700°C. Samples were supplied by D. M. Brown of General Electric Research & Development Laboratory, Schenectady, NY.

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1250-kilovolt scanning transmission electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113007 ◽

1984 ◽

Vol 42 ◽

pp. 624-625

Author(s):

T. Imura ◽

S. Maruse ◽

K. Mihama ◽

M. Iseki ◽

M. Hibino ◽

...

Keyword(s):

High Voltage ◽

Electron Probe ◽

Scanning Transmission Electron Microscope ◽

Pressure Vessels ◽

Practical Applications ◽

Voltage Generator ◽

Transmission Electron ◽

Scanning Transmission ◽

New Applications ◽

High Voltage Generator

Ultra high voltage STEM has many inherent technical advantages over CTEM. These advantages include better signal detectability and signal processing capability. It is hoped that it will explore some new applications which were previously not possible. Conventional STEM (including CTEM with STEM attachment), however, has been unable to provide these inherent advantages due to insufficient performance and engineering problems. Recently we have developed a new 1250 kV STEM and completed installation at Nagoya University in Japan. It has been designed to break through conventional engineering limitations and bring about theoretical advantage in practical applications.In the design of this instrument, we exercised maximum care in providing a stable electron probe. A high voltage generator and an accelerator are housed in two separate pressure vessels and they are connected with a high voltage resistor cable.(Fig. 1) This design minimized induction generated from the high voltage generator, which is a high frequency Cockcroft-Walton type, being transmitted to the electron probe.

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Characterization of intergranular cuprous oxide in polycrystalline YBa2Cu3O7-x

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106466 ◽

1988 ◽

Vol 46 ◽

pp. 880-881

Author(s):

Bradley L. Thiel ◽

Chan Han R. P. ◽

Kurosky L. C. Hutter ◽

I. A. Aksay ◽

Mehmet Sarikaya

Keyword(s):

Grain Boundary ◽

Cuprous Oxide ◽

Room Temperature ◽

Boundary Phase ◽

Spectroscopic Techniques ◽

Transition Width ◽

Practical Applications ◽

Thin Foils ◽

Superconducting Oxides

The identification of extraneous phases is important in understanding of high Tc superconducting oxides. The spectroscopic techniques commonly used in determining the origin of superconductivity (such as RAMAN, XPS, AES, and EXAFS) are surface-sensitive. Hence a grain boundary phase several nanometers thick could produce irrelevant spectroscopic results and cause erroneous conclusions. The intergranular phases present a major technological consideration for practical applications. In this communication we report the identification of a Cu2O grain boundary phase which forms during the sintering of YBa2Cu3O7-x (1:2:3 compound).Samples are prepared using a mixture of Y2O3. CuO, and BaO2 powders dispersed in ethanol for complete mixing. The pellets pressed at 20,000 psi are heated to 950°C at a rate of 5°C per min, held for 1 hr, and cooled at 1°C per min to room temperature. The samples show a Tc of 91K with a transition width of 2K. In order to prevent damage, a low temperature stage is used in milling to prepare thin foils which are then observed, using a liquid nitrogen holder, in a Philips 430T at 300 kV.

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