Broadband reflectors with a disordered layered structure: statistical properties of high performing configurations selected via genetic algorithm

2022 ◽  
Author(s):  
Vincenzo Fiumara ◽  
Paolo Addesso ◽  
Francesco Chiadini ◽  
Antonio Scaglione
Keyword(s):  
Genetic Algorithm ◽  
Statistical Analysis ◽  
Layered Structure ◽  
High Performance ◽  
Dielectric Materials ◽  
High Performing ◽  
Visible Wavelength Range ◽  
Narrow Bands ◽  
Very High ◽  
Key Parameter

Abstract Disordered multilayers consisting of alternating layers of two lossless dielectric materials with random thicknesses can behave as good reflectors in wide wavelength ranges except for narrow bands where the transmittance is significative. We use a dedicated genetic algorithm to select different configurations (thickness sequences) of such structures which exhibit very low transmittance in the entire visible wavelength range, showing that broadband disordered reflectors with very high performance can be designed. A statistical analysis of the thickness sequences selected by the genetic algorithm reveals that such sequences are characterized by correlated disorder and that the degree of autocorrelation is a key parameter in determining the reflection performance.

scholarly journals Pareto Optimization of Oligomer Polarizability and Dipole Moment using a Genetic Algorithm

2021 ◽  
Author(s):  
Danielle Hiener ◽  
Geoffrey Hutchison
Keyword(s):  
Genetic Algorithm ◽  
Dipole Moment ◽  
High Performance ◽  
Density Functional ◽  
Chemical Space ◽  
Dipole Moments ◽  
Tight Binding ◽  
Dielectric Materials ◽  
Underlying Structure ◽  
Large Set

High performance electronic components are highly sought after in order to produce increasingly smaller and cheaper electronic devices. Drawing inspiration from inorganic dielectric materials, in which both polarizability and polarization contribute, organic materials can also maximize both. For a large set of small molecules drawn from PubChem, a Pareto-like front appears between polarizability and dipole moment indicating the presence of an apparent trade-off between these two properties. We tested this balance in π-conjugated materials by searching for novel conjugated hexamers with simultaneously large polarizabilities and dipole moments with potential use for dielectric materials. Using a genetic algorithm (GA) screening technique in conjunction with an approximate density functional tight binding method (GFN2-xTB) for property calculations, we were able to efficiently search chemical space for optimal hexamers. Given the scope of chemical space, using the GA technique saves considerable time and resources by speeding up molecular searches compared to a systematic search. We also explored the underlying structure-function relationships, including sequence and monomer properties, that characterize large polarizability and dipole moment regimes.

scholarly journals Pareto Optimization of Oligomer Polarizability and Dipole Moment using a Genetic Algorithm

2021 ◽  
Author(s):  
Danielle Hiener ◽  
Geoffrey Hutchison
Keyword(s):  
Genetic Algorithm ◽  
Dipole Moment ◽  
High Performance ◽  
Density Functional ◽  
Chemical Space ◽  
Dipole Moments ◽  
Tight Binding ◽  
Dielectric Materials ◽  
Underlying Structure ◽  
Large Set

High performance electronic components are highly sought after in order to produce increasingly smaller and cheaper electronic devices. Drawing inspiration from inorganic dielectric materials, in which both polarizability and polarization contribute, organic materials can also maximize both. For a large set of small molecules drawn from PubChem, a Pareto-like front appears between polarizability and dipole moment indicating the presence of an apparent trade-off between these two properties. We tested this balance in π-conjugated materials by searching for novel conjugated hexamers with simultaneously large polarizabilities and dipole moments with potential use for dielectric materials. Using a genetic algorithm (GA) screening technique in conjunction with an approximate density functional tight binding method (GFN2-xTB) for property calculations, we were able to efficiently search chemical space for optimal hexamers. Given the scope of chemical space, using the GA technique saves considerable time and resources by speeding up molecular searches compared to a systematic search. We also explored the underlying structure-function relationships, including sequence and monomer properties, that characterize large polarizability and dipole moment regimes.

Beveridge, Bismarck and Southern European Health Care Systems: Can We Decide Which is the Best in EU-15? A Statistical Analysis

2017 ◽  
Vol 1 (1) ◽  
pp. 41
Author(s):  
Angeliki Moisidou
Keyword(s):  
Health Care ◽  
Statistical Analysis ◽  
Empirical Analysis ◽  
Access To Health Care ◽  
High Performance ◽  
Social Protection ◽  
Health Care Systems ◽  
Health Sector ◽  
Economic Cost ◽  
Care Systems

A statistical analysis has been conducted with the aim to elucidate the effect of health care systems (HSs) on health inequalities assessed in terms of (a) differential access to health care services and (b) varying health outcomes among different models of HSs in EU-15 ((Beveridge: UK, IE, SE, FI, DK), (Bismarck: DE, FR, BE, LU, AT, NL), (Southern European model: GR, IT, ES, PT)). In the effort to interpret the results of the empirical analysis, we have ascertained systematic differences among the HSs in EU-15. Specifically, it is concluded that countries with Beveridge HS can be characterized more efficient (than average) in the most examined correlations, showing particularly high performance in the health sector. Similarly, countries with Bismarck HS record fairly satisfactory performance, but simultaneously they display more structural weaknesses compared with the Beveridge model. In addition, our empirical analysis has shown that adopting Bismarck model requires higher economic cost, compared with the Beveridge model, which is directly financed by taxation. On the contrary, in the countries with Southern European HS, the lowest performances are generally identified, which can be attributed to the residual social protection that characterizes these countries. The paper concludes with a synthesis of the empirical findings of our research. It proposes some directions for further research and presents a set of implications for policymakers regarding the planning and implementation of appropriate policies in order to tackle health inequality within HSs.

التغير المناخي واثره في المقنن المائي لمحصول العنب في محافظة ديالى

2019 ◽  
Vol 1 (34) ◽  
pp. 391-422
Author(s):  
اشواق حسن حميد صالح
Keyword(s):  
Climate Change ◽  
Statistical Analysis ◽  
Wind Speed ◽  
Extreme Temperature ◽  
Solar Brightness ◽  
The Subject ◽  
Climate Station ◽  
The Times ◽  
High Level ◽  
Very High

Climate change and its impact on water resources is the problem of the times. Therefore, this study is concerned with the subject of climate change and its impact on the water ration of the grape harvest in Diyala Governorate. The study was based on the data of the Khanaqin climate station for the period 1973-2017, (1986-2017) due to lack of data at governorate level. The general trend of the elements of the climate and its effect on the water formula was extracted. The equation of change was extracted for the duration of the study. The statistical analysis was also used between the elements of the climate (actual brightness, normal temperature, micro and maximum degrees Celsius, wind speed m / s, relative humidity% The results of the statistical analysis confirm that the water ration for the study area is based mainly on the X7 evaporation / netting variable, which is affected by a set of independent variables X1 Solar Brightness X4 X5 Extreme Temperature Wind Speed ​​3X Minimal Temperature and Very High Level .

KEMPER C688

Alloy Digest ◽  
2017 ◽  
Vol 66 (12) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Copper Alloy ◽  
High Performance ◽  
High Conductivity ◽  
Bend Strength ◽  
Very High

Abstract Alloy C688 is a high-performance copper alloy with very high conductivity. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming and joining. Filing Code: Cu-867. Producer or source: Gebr. Kemper GmbH + Company KG Metallwerke.

KEMPER KHP7025

Alloy Digest ◽  
2017 ◽  
Vol 66 (10) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Copper Alloy ◽  
High Performance ◽  
High Conductivity ◽  
Bend Strength ◽  
Very High

Abstract Alloy KHP 7025 (UNS C70250) is a high-performance copper alloy with very high conductivity. Uses include connector springs, tabs, contact springs, switches, relays, and leadframes. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming, machining, and joining. Filing Code: Cu-865. Producer or source: Gebr. Kemper GmbH + Company KG Metallwerke.

About Measures of the State Support for Technical Equipment of Agricultural Producers

2020 ◽  
pp. 20-27
Author(s):  
A.Ya. Kibirov ◽  
Keyword(s):  
Statistical Analysis ◽  
Energy Saving ◽  
High Performance ◽  
The State ◽  
Agricultural Products ◽  
Technical Equipment ◽  
Agricultural Machinery ◽  
State Support ◽  
Agricultural Producers ◽  
Technical Base

The article uses methods of statistical analysis, deduction and analogy to consider programs at the Federal, regional and economic levels, which provide for measures aimed at improving the technical equipment of agricultural producers. Particular attention is paid to the acquisition of energy-saving, high-performance agricultural machinery and equipment used in the production and processing of agricultural products. An assessment of the effectiveness of state support for updating the material and technical base of agriculture is given. Based on the results of the study, conclusions and recommendations were formulated.

Use of activated carbon to remove undesirable residual amylase from refinery streams

2017 ◽  
pp. 96-103 ◽  
Author(s):  
Gillian Eggleston ◽  
Isabel Lima ◽  
Emmanuel Sarir ◽  
Jack Thompson ◽  
John Zatlokovicz ◽  
...  
Keyword(s):  
Activated Carbon ◽  
High Temperature ◽  
High Performance ◽  
Activated Carbons ◽  
Amylase Activity ◽  
Sugar Industry ◽  
End User ◽  
Customer Complaints ◽  
Carry Over ◽  
Very High

In recent years, there has been increased world-wide concern over residual (carry-over) activity of mostly high temperature (HT) and very high temperature (VHT) stable amylases in white, refined sugars from refineries to various food and end-user industries. HT and VHT stable amylases were developed for much larger markets than the sugar industry with harsher processing conditions. There is an urgent need in the sugar industry to be able to remove or inactivate residual, active amylases either in factory or refinery streams or both. A survey of refineries that used amylase and had activated carbon systems for decolorizing, revealed they did not have any customer complaints for residual amylase. The use of high performance activated carbons to remove residual amylase activity was investigated using a Phadebas® method created for the sugar industry to measure residual amylase in syrups. Ability to remove residual amylase protein was dependent on the surface area of the powdered activated carbons as well as mixing (retention) time. The activated carbon also had the additional benefit of removing color and insoluble starch.

scholarly journals SERS Biosensor Based on Engineered 2D-Aperiodic Nanostructure for In-Situ Detection of Viable Brucella Bacterium in Complex Matrix

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 886
Author(s):  
Massimo Rippa ◽  
Riccardo Castagna ◽  
Domenico Sagnelli ◽  
Ambra Vestri ◽  
Giorgia Borriello ◽  
...  
Keyword(s):  
High Performance ◽  
Foodborne Pathogen ◽  
Surface Enhanced Raman Spectroscopy ◽  
High Performing ◽  
Sensing Platform ◽  
Food Detection ◽  
Raman Enhancement ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
In Situ Detection

Brucella is a foodborne pathogen globally affecting both the economy and healthcare. Surface Enhanced Raman Spectroscopy (SERS) nano-biosensing can be a promising strategy for its detection. We combined high-performance quasi-crystal patterned nanocavities for Raman enhancement with the use of covalently immobilized Tbilisi bacteriophages as high-performing bio-receptors. We coupled our efficient SERS nano-biosensor to a Raman system to develop an on-field phage-based bio-sensing platform capable of monitoring the target bacteria. The developed biosensor allowed us to identify Brucella abortus in milk by our portable SERS device. Upon bacterial capture from samples (104 cells), a signal related to the pathogen recognition was observed, proving the concrete applicability of our system for on-site and in-food detection.

scholarly journals Decoupling electron and phonon transport in single-nanowire hybrid materials for high-performance thermoelectrics

2021 ◽  
Vol 7 (20) ◽  
pp. eabe6000
Author(s):  
Lin Yang ◽  
Madeleine P. Gordon ◽  
Akanksha K. Menon ◽  
Alexandra Bruefach ◽  
Kyle Haas ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Transport ◽  
Electrical Transport ◽  
High Performance ◽  
Figure Of Merit ◽  
Phonon Transport ◽  
Core Shell ◽  
Nanowire Diameter ◽  
High Performing ◽  
Polycrystalline Thin Films

Organic-inorganic hybrids have recently emerged as a class of high-performing thermoelectric materials that are lightweight and mechanically flexible. However, the fundamental electrical and thermal transport in these materials has remained elusive due to the heterogeneity of bulk, polycrystalline, thin films reported thus far. Here, we systematically investigate a model hybrid comprising a single core/shell nanowire of Te-PEDOT:PSS. We show that as the nanowire diameter is reduced, the electrical conductivity increases and the thermal conductivity decreases, while the Seebeck coefficient remains nearly constant—this collectively results in a figure of merit, ZT, of 0.54 at 400 K. The origin of the decoupling of charge and heat transport lies in the fact that electrical transport occurs through the organic shell, while thermal transport is driven by the inorganic core. This study establishes design principles for high-performing thermoelectrics that leverage the unique interactions occurring at the interfaces of hybrid nanowires.

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