Adaptive Correspondence Experiments

2021 ◽  
Vol 111 ◽  
pp. 43-48
Author(s):  
Hadar Avivi ◽  
Patrick Kline ◽  
Evan Rose ◽  
Christopher Walters
Keyword(s):  
Experimental Data ◽  
Fixed Number ◽  
Employer Perceptions

Correspondence experiments probe for discrimination by manipulating employer perceptions of applicant characteristics. We consider the gains from dynamically adapting the number and quality of fictitious applications each employer receives to their prior callback decisions. Calibrating employer behavior to experimental data from Nunley et al. (2015), we find that it is possible to cut the number of applications required to detect a fixed number of discriminators roughly in half relative to a benchmark design with a fixed number of applications per job. These gains are achieved primarily from abandoning jobs with very low callback probabilities and those that call back Black applicants.

Орошение томата F1 Донской в открытом грунте Московской области

2019 ◽  
Author(s):  
D.I. Engalychev ◽  
N.A. Engalycheva ◽  
A.M. Menshikh
Keyword(s):  
Experimental Data ◽  
Agricultural Technology ◽  
Tomato Fruits ◽  
River Floodplain ◽  
Yield And Quality ◽  
Open Ground ◽  
Alluvial Meadow ◽  
Standard Production ◽  
Moscow River

Представлены экспериментальные данные о влиянии капельного орошения на урожайность и качество плодов томата при выращивании культуры в открытом грунте Московской области. На плодородных аллювиальных луговых почвах Москворецкой поймы при соблюдении агротехники без орошения в среднем за три года исследований в полевых условиях получена урожайность томата F1 Донской 31,9 т/га, с орошением 48,5 т/га, в т.ч. стандартной продукции 42,6 т/га.The article presents experimental data on the effect of drip irrigation on the yield and quality of tomato fruits when growing crops in open ground of the Moscow Region. On fertile alluvial meadow soils of the Moscow river floodplain, with the observance of agricultural technology without irrigation, the field yield of tomato hybrid F1 Donskoi on average for three years of research was 31.9 t/ha, with irrigation 48.5 t/ha, incl. standard production 42.6 t/ha.

A Cyclic Plasticity Modeling for Uniaxial and Multiaxial Ratcheting Simulation of Austenitic Steel

2012 ◽  
Author(s):  
Salim Meziani ◽  
Lynda Djimli
Keyword(s):  
Experimental Data ◽  
Stainless Steel ◽  
Constitutive Model ◽  
Data Base ◽  
Good Choice ◽  
Cyclic Plasticity ◽  
Strain History ◽  
Material Parameters ◽  
Plastic Shakedown

The first objective of this paper investigates the influence of the previous strain history on ratcheting of the 304 L stainless steel on ambient temperature. The identification is done using the Chaboche constitutive model. New tests were performed where different strain-controlled histories have been applied prior to ratcheting tests. It is demonstrated that under the same conditions, one can observe ratcheting, plastic shakedown or elasticity according to the prior strain-controlled history. The second objective points out the correlation between the experimental data base devoted to the identification of the material parameters and the quality of the predictions in cyclic plasticity. The results suggest that the choice of the tests should be closely linked to the capabilities of the model. In particular, the presence of non proportional strain-controlled tests in the data base may be not a good choice if the model itself is not able to represent explicitly such a character.

Thermal Laser Separation – A Novel Dicing Technology Fulfilling the Demands of Volume Manufacturing of 4H-SiC Devices

2015 ◽  
Vol 821-823 ◽  
pp. 528-532 ◽  
Author(s):  
Dirk Lewke ◽  
Karl Otto Dohnke ◽  
Hans Ulrich Zühlke ◽  
Mercedes Cerezuela Barret ◽  
Martin Schellenberger ◽  
...  
Keyword(s):  
Experimental Data ◽  
Process Control ◽  
Tool Wear ◽  
Large Scale ◽  
State Of The Art ◽  
Scale Production ◽  
High Quality ◽  
Large Scale Production ◽  
Laser Separation

One challenge for volume manufacturing of 4H-SiC devices is the state-of-the-art wafer dicing technology – the mechanical blade dicing which suffers from high tool wear and low feed rates. In this paper we discuss Thermal Laser Separation (TLS) as a novel dicing technology for large scale production of SiC devices. We compare the latest TLS experimental data resulting from fully processed 4H-SiC wafers with results obtained by mechanical dicing technology. Especially typical product relevant features like process control monitoring (PCM) structures and backside metallization, quality of diced SiC-devices as well as productivity are considered. It could be shown that with feed rates up to two orders of magnitude higher than state-of-the-art, no tool wear and high quality of diced chips, TLS has a very promising potential to fulfill the demands of volume manufacturing of 4H-SiC devices.

Textiles and perishable materials

2018 ◽  
Author(s):  
Johanna Banck-Burgess
Keyword(s):  
Experimental Data ◽  
Everyday Life ◽  
Iron Age ◽  
Raw Materials ◽  
Visual Representations ◽  
Detailed Knowledge ◽  
Textile Production ◽  
Funerary Rituals ◽  
The Status

This chapter challenges traditional views on Iron Age dress. Recent research has greatly enhanced our understanding of how textiles were manufactured in Iron Age Europe. The variety of qualities, textures, techniques, raw materials, colours, and cuts give insights into the detailed knowledge of the craftspeople involved. Textiles used for dress, blankets, or furniture fittings were appreciated not only for their appearance, but also for the quality of the work. In everyday life, their optical qualities were used to express and signal gender, social roles and status, while the labour expended on textiles found in wealthy burials underlines both the status of the deceased and the extent of conspicuous consumption in funerary rituals—for instance, for wrapping grave furniture and goods. The chapter also looks at experimental data showing how labour-intensive textile production was, and the types of clothing and accessories found in different archaeological contexts or depicted in visual representations.

scholarly journals ESTIMATION OF STRUCTURAL SIMILARITY FOR CONTROL OF MICROELECTRONIC PRODUCTS

2019 ◽  
Vol 1 (7) ◽  
pp. 14-18
Author(s):  
Yu. A. Gusman ◽  
Yu. A. Pichugin ◽  
A. O. Smirnov
Keyword(s):  
Production Process ◽  
Technological Process ◽  
Good Reason ◽  
Structural Similarity ◽  
Fixed Number ◽  
Crystal Plate ◽  
Technological Scheme ◽  
Real Sample ◽  
Numerical Example

In this paper we consider the technological process of manufacturing micromechanical gyroscopes, the output of which is divided into cells of the crystal plate and each cell contains a fixed number of product elements. The estimation of structural similarity for measurements of technical characteristics of various devices is offered. A relatively large value of structural similarity assessment means that there is a dependence of the quality of the manufactured devices on the position on the crystal plate. This gives a good reason for further work to improve the quality of the process or to change the technological scheme as a whole. The article considers a numerical example based on a real sample of microelectronic products. The proposed method can be used both in the process of adjustment of the production process and in the rejection of products, when further configuration of the equipment is no longer possible.

Solving the inverse problem for aggregation in activated sludge flocculation using a population balance framework

2007 ◽  
Vol 56 (6) ◽  
pp. 95-103 ◽  
Author(s):  
I. Nopens ◽  
N. Nere ◽  
P.A. Vanrolleghem ◽  
D. Ramkrishna
Keyword(s):  
Experimental Data ◽  
Inverse Problem ◽  
Particle Size ◽  
Activated Sludge ◽  
Predictive Power ◽  
Population Balance ◽  
Model Structure ◽  
Forward Simulation ◽  
Floc Size

Many systems contain populations of individuals. Often, they are regarded as a lumped phase, which might, for some applications, lead to inadequate model predictive power. An alternative framework, Population Balance Models, has been used here to describe such a system, activated sludge flocculation in which particle size is the property one wants to model. An important problem to solve in population balance modelling is to determine the model structure that adequately describes experimentally obtained data on for instance, the time evolution of the floc size distribution. In this contribution, an alternative method based on solving the inverse problem is used to recover the model structure from the data. In this respect, the presence of similarity in the data simplifies the problem significantly. Similarity was found and the inverse problem could be solved. A forward simulation then confirmed the quality of the model structure to describe the experimental data.

Modelling the reduction of zinc from oxide melt

2021 ◽  
pp. 18-22
Author(s):  
A. S. Vusikhis ◽  
E. N. Selivanov ◽  
L. I. Leontiev ◽  
S. N. Tyushnyakov
Keyword(s):  
Experimental Data ◽  
Carbon Monoxide ◽  
Basic Research ◽  
Metallic Phase ◽  
Thermodynamic Modelling ◽  
Reduction Degree ◽  
Similar Reduction ◽  
Oxide Melt ◽  
Higher Temperature

For predicting the results of sparging processes to understand how much metal can be reduced from oxide melt, a method of thermodynamic modelling has been developed that ensures approximation to real systems in which the metallic phase and gases are removed from the liquid at a certain interval. The key principle of this method is that equilibrium is determined for every single portion of introduced gas, and the concentration of oxides of the reduced metals in each cycle is taken from the previous data. Such approach enables a very close simulation of real processes so that one can have an idea about the quality of reactions taking place in pyrometallurgical units. When the thermodynamic modelling method was applied to the processes of iron and nickel reduction, the obtained results well matched the experimental data. A comparative analysis was carried out to understand how the temperature T and the amount of introduced gas VСО or VН2 influence the process of zinc reduction from oxide melt. For the purposes of modelling, a B2O3 – CaO – ZnO melt was used with the B2O3/CaO ratio equal to 3 (which corresponds to the eutectic composition) and with the initial ZnO concentration in the range from 3 to 12 %; the temperature range used was 1273–1673 K. The concentration of zinc oxide СZnO in the melt, as well as the reduction degree Zn were analyzed. The correlation dependences СZnO, φZn = f(C0, T, VCO or VH2) are presented in the form of second order polynomials. Reduction of zinc with hydrogen is a more intense process than when zinc is reduced with carbon monoxide. Therefore, less gas is required to reach a similar reduction degree. A higher temperature facilitates the reduction of zinc while less СО or Н2 is required to achieve the target reduction degree φZn. Irrespective of the initial composition of the melt, it takes 1.5 times less hydrogen that carbon monoxide to obtain the unit mass of zinc with the process temperature being the same. The obtained data explain the changing zinc distillation performance when changing the temperature. The established relationships between CZnO and φZn and the temperature and the amount of introduced gas are useful for predicting the zinc distillation performance and can be used as basic relationships for analyzing experimental data. This research was funded by the Russian Foundation for Basic Research under the Project No. 18-29-24093мк.

scholarly journals Spectral Processing for Denoising and Compression of 3D Meshes Using Dynamic Orthogonal Iterations

2020 ◽  
Vol 6 (6) ◽  
pp. 55
Author(s):  
Gerasimos Arvanitis ◽  
Aris S. Lalos ◽  
Konstantinos Moustakas
Keyword(s):  
Computational Complexity ◽  
Laplacian Matrix ◽  
3D Models ◽  
Graph Laplacian ◽  
Fixed Number ◽  
Spectral Processing ◽  
Reconstruction Quality ◽  
And Performance ◽  
Optimal Subspace

Recently, spectral methods have been extensively used in the processing of 3D meshes. They usually take advantage of some unique properties that the eigenvalues and the eigenvectors of the decomposed Laplacian matrix have. However, despite their superior behavior and performance, they suffer from computational complexity, especially while the number of vertices of the model increases. In this work, we suggest the use of a fast and efficient spectral processing approach applied to dense static and dynamic 3D meshes, which can be ideally suited for real-time denoising and compression applications. To increase the computational efficiency of the method, we exploit potential spectral coherence between adjacent parts of a mesh and then we apply an orthogonal iteration approach for the tracking of the graph Laplacian eigenspaces. Additionally, we present a dynamic version that automatically identifies the optimal subspace size that satisfies a given reconstruction quality threshold. In this way, we overcome the problem of the perceptual distortions, due to the fixed number of subspace sizes that is used for all the separated parts individually. Extensive simulations carried out using different 3D models in different use cases (i.e., compression and denoising), showed that the proposed approach is very fast, especially in comparison with the SVD based spectral processing approaches, while at the same time the quality of the reconstructed models is of similar or even better reconstruction quality. The experimental analysis also showed that the proposed approach could also be used by other denoising methods as a preprocessing step, in order to optimize the reconstruction quality of their results and decrease their computational complexity since they need fewer iterations to converge.

scholarly journals Fire Behavior of the Assembled Monolithic Hollow-Ribbed Slabs

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
B. Li ◽  
Y. Q. Lin ◽  
H. L. Zhang ◽  
M. J. Ma
Keyword(s):  
Experimental Data ◽  
Optimum Design ◽  
Fire Resistance ◽  
Fire Behavior ◽  
Great Influence ◽  
Fire Tests ◽  
Structural Fire ◽  
Temperature Distributions ◽  
Comparison Of The Results

This paper presents the results from the furnace tests conducted on two assembled monolithic hollow-ribbed (AMH) slabs consisting of the open box and the covered box, respectively. Detailed experimental data in the form of describing slab cracking or spalling, furnace temperatures, temperature distributions, and vertical deflections are presented. Comparison of the results from the two fire tests indicates that the covered box shows better fire resistance compared to the open box; thus, the covered box is recommended to adopt in structural fire-resistant design. However, they are both prone to cracking or spalling at their bottom surfaces during the fire tests, so the AMH slab still needs further optimum design to meet its requirements of fire resistance and service function. In addition, the sealing quality of congruent boxes also has a great influence on the fire resistance of the AMH slab.

The Contrast Research of the Finite Element Simulation for Ordinary and Fine Blanking with Negative Clearance

2008 ◽  
Vol 575-578 ◽  
pp. 316-321 ◽  
Author(s):  
H. Du ◽  
S.M. Ding
Keyword(s):  
Experimental Data ◽  
Reference Value ◽  
Engineering Practice ◽  
Fine Blanking ◽  
Equipment Investment ◽  
Element Simulation ◽  
Negative Clearance ◽  
Material Energy ◽  
Blanking Process

This paper puts forward a negative clearance fine-blanking theory and its technique process, and introduces the technical processing of fine-blanking which can be used on ordinary punching machines. In this paper, computer simulation and the experimental study of negative clearance fine-blanking process are carried out. Thus the parameters of the force of blanking, the value of negative clearance are determined. The effect of fine-blanking quality was obtained, and the perfect rate of the blanking fracture achieves 90%. By comparing negative clearance precise blanking with conventional blanking, the following conclusions are drawn: 1. Blanking quality of negative clearance blanking is increased by 57% than that of conventional blanking. 2. The down surface of the work-pieces obtained by the conventional blanking processing have 0.2 - 0.5 mm longitudinal burrs, while the work-pieces obtained by the negative clearance blanking have no burrs. Thus the processing of clear away the burrs could be spared. And the manpower, the material, energy and the equipment investment are saved. The researching result provides theoretic reference and the experimental data for the engineering practice. It has instructive significance and reference value to engineering manufacturing.

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