scholarly journals Comprehensive analysis of an optimized near-field tandem thermophotovoltaic converter

2022 ◽  
Vol 236 ◽  
pp. 111522
Author(s):  
Jaeman Song ◽  
Minwoo Choi ◽  
Mikyung Lim ◽  
Jungchul Lee ◽  
Bong Jae Lee
Keyword(s):  
Near Field ◽  
Comprehensive Analysis

scholarly journals Casimir Forces Out of Thermal Equilibrium Near A Superconducting Transition

2021 ◽  
Author(s):  
Shunashi Guadalupe Castillo-López ◽  
Raúl Esquivel-Sir ◽  
Giuseppe Pirruccio ◽  
Carlos Villarreal
Keyword(s):  
Direct Measurement ◽  
Thermal Effects ◽  
Thermal Equilibrium ◽  
Near Field ◽  
Zero Point ◽  
Comprehensive Analysis ◽  
Superconducting Transition ◽  
Casimir Forces ◽  
Point Energy ◽  
Plate Distance

Abstract We present a comprehensive analysis of the out-of-equilibrium Casimir pressure between two high-T c superconducting plates, each kept at a different temperature. Two interaction regimes can be distinguished. While the zero-point energy dominates in the near field, thermal effects become important at large interplate separations causing a drop in the force’s magnitude compared with the usual thermal-equilibrium case. Our detailed calculations highlight the competing role played by propagating and evanescent modes. Moreover, as one of the plates undergoes the superconducting transition, we predict a sudden discontinuity in the force for any plate distance, which has not been previously observed in other systems. The sensitivity of the dielectric function of the high-T c superconductors makes them ideal systems for a possible direct measurement of the out-of-equilibrium Casimir pressure.

On blast waves in exponential atmospheres

1975 ◽  
Vol 71 (1) ◽  
pp. 105-122 ◽  
Author(s):  
G. G. Bach ◽  
A. L. Kuhl ◽  
A. K. Oppenheim
Keyword(s):  
Approximate Solution ◽  
Exact Analytical Solution ◽  
Perturbation Technique ◽  
Near Field ◽  
Equations Of Motion ◽  
Comprehensive Analysis ◽  
Blast Waves ◽  
Far Field ◽  
Strong Explosion ◽  
Short Times

The paper presents a comprehensive analysis of gas motion created by a strong explosion in an atmosphere whose density is an exponential function of altitude. For the near field (i.e. short times after initiation), an exact analytical solution of the equations of motion is obtained by means of a perturbation technique. For the far field (i.e. long times after initiation), a similarity solution associated with a logarithmic front trajectory is derived. The two are shown to be well matched with each other. Finally, a fully-algebraic approximate solution is given that qualitatively reproduces all the salient features of the exact and asymptotic solutions, while quantitatively it is in fair agreement with their results.

Measurement Uncertainty Analysis in Determining Adiabatic Film Cooling Effectiveness by Using Pressure Sensitive Paint Technique

2016 ◽  
Vol 138 (12) ◽  
Author(s):  
Blake Johnson ◽  
Hui Hu
Keyword(s):  
Measurement Uncertainty ◽  
Film Cooling ◽  
Near Field ◽  
Isothermal Condition ◽  
Comprehensive Analysis ◽  
Pressure Sensitive Paint ◽  
Cooling Effectiveness ◽  
Total Uncertainty ◽  
Film Cooling Effectiveness ◽  
Pressure Sensitive

While pressure sensitive paint (PSP) technique has been widely used to measure adiabatic film cooling effectiveness distributions on the surfaces of interest based on a mass transfer analog to traditional thermal-based measurements, very little can be found in literature to provide a comprehensive analysis on the uncertainty levels of the measured film cooling effectiveness distributions derived from PSP measurements. In the present study, a detailed analysis is performed to evaluate the effects of various associated uncertainties in the PSP measurements on the measured film cooling effectiveness distributions over the surfaces of interest. The experimental study is conducted in a low-speed wind tunnel under an isothermal condition. While airflow is used to represent the “hot” mainstream flow, an oxygen-free gas, i.e., carbon dioxide (CO2) gas with a density ratio of DR = 1.5 for the present study, is supplied to simulate the “coolant” stream for the PSP measurements to map the adiabatic film cooling effectiveness distribution over a flat test plate with an array of five cylindrical coolant holes at a span-wise spacing of three diameters center-to-center. A comprehensive analysis was carried out with focus on the measurement uncertainty and process uncertainty for the PSP measurements to determine the film cooling effectiveness distributions over the surface of interest. The final analysis indicates that the total uncertainty in the adiabatic film cooling effectiveness measurements by using the PSP technique depends strongly on the local behavior of the mixing process between the mainstream and coolant flows. The measurement uncertainty is estimated as high as 5% at the near field behind the coolant holes. In the far field away from the coolant holes, the total measurement uncertainty is found to be more uniform throughout the measurement domain and generally lower than those in the near field at about 3%.

Near-field scanning optical microscopy

1986 ◽  
Vol 44 ◽  
pp. 642-643
Author(s):  
E. Betzig ◽  
A. Harootunian ◽  
M. Isaacson ◽  
A. Lewis
Keyword(s):  
Near Field ◽  
Optical Microscope ◽  
Visible Radiation ◽  
Field Methods ◽  
Optical Elements ◽  
Optical Region ◽  
Order Of Magnitude ◽  
Nondestructive Imaging ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning

In general, conventional methods of optical imaging are limited in spatial resolution by either the wavelength of the radiation used or by the aberrations of the optical elements. This is true whether one uses a scanning probe or a fixed beam method. The reason for the wavelength limit of resolution is due to the far field methods of producing or detecting the radiation. If one resorts to restricting our probes to the near field optical region, then the possibility exists of obtaining spatial resolutions more than an order of magnitude smaller than the optical wavelength of the radiation used. In this paper, we will describe the principles underlying such "near field" imaging and present some preliminary results from a near field scanning optical microscope (NS0M) that uses visible radiation and is capable of resolutions comparable to an SEM. The advantage of such a technique is the possibility of completely nondestructive imaging in air at spatial resolutions of about 50nm.

Principles of Planar Near-Field Antenna Measurements

2007 ◽  
Author(s):  
Stuart Gregson ◽  
John McCormick ◽  
Clive Parini
Keyword(s):  
Near Field ◽  
Antenna Measurements

Sozial-räumliche Dynamiken der Agrartreibstoffe.

2016 ◽  
Vol 46 (184) ◽  
pp. 423-440 ◽  
Author(s):  
Kristina Dietz ◽  
Bettina Engels ◽  
Oliver Pye
Keyword(s):  
Political Economy ◽  
Capital Flows ◽  
Spatial Dynamics ◽  
Financial Sector ◽  
Comprehensive Analysis ◽  
Spatial Theory ◽  
Global Political Economy

This article explores the spatial dynamics of agrofuels. Building on categories from the field of critical spatial theory, it shows how these categories enable a comprehensive analysis of the spatial dynamics of agrofuels that links the macro-structures of the global political economy to concrete, place-based struggles. Four core socio-spatial dynamics of agrofuel politics are highlighted and applied to empirical findings: territorialization, the financial sector as a new scale of regulation, place-based struggles and transnational spaces of resources and capital flows.

Concerning the abuse of power by an official

2020 ◽  
pp. 103-110
Author(s):  
Ihor Oheruk
Keyword(s):  
Criminal Code ◽  
Comprehensive Analysis ◽  
Practical Significance ◽  
Abuse Of Power ◽  
Government Functions ◽  
Analysis And Synthesis ◽  
The Status ◽  
The Subject ◽  
Criminal Legislation ◽  
Logical Semantic

Purpose. The purpose of the work is to analyze the application of the second and third parts of Article 3692 of the Criminal Code of Ukraine to officials in the context, that defines them by the Criminal Code of Ukraine in the note to Article 364 of the Criminal Code of Ukraine. Methodology. The methodology includes a comprehensive analysis and synthesis of the available scientific and theoretical material and the formulation of relevant conclusions and recommendations. In the course of the study, the following methods of scientific knowledge were used: terminological, logical-semantic, system-structural, logical-normative. Results: in the course of research the cause of criminalization of such act as "abuse of power" is considered, the subject of the specified criminal act which has the features of "an official" in the context, that defines it by the note to Article 364 of the Criminal Code of Ukraine is analyzed and the main ways of committing criminal acts, that are provided for in this article of the Criminal Code of Ukraine are identified. Originality. The study found, that one of the key conditions for the opportunity to influence officials, that are authorized to perform government or local self-government functions, is the position held by the official and the related opportunities. Therefore, taking into account the opinion of the scientists, that the subject of crimes, that are provided for by the second and third parts of Article 3692 is special, the peculiarities of which is the cumulative feature, that denotes, that such person is not endowed with the status of an official, well-founded need to specify the criminal legislation of Ukraine in terms of the application the second and third parts of Article 3692 of the Criminal code of Ukraine concerning officials in the context, that defines them by the criminal legislation of Ukraine in the note to Article 364 of the Criminal Code of Ukraine. Practical significance. The research results can be used in lawmaking in the improvement of anti-corruption legislation.

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