scholarly journals AIMFAST: Initial Dish System Alignments Results Using Fringe Reflection Methods

2011 ◽  
Author(s):  
Charles E. Andraka ◽  
Julius Yellowhair ◽  
Nolan Finch ◽  
Jeff Carlson ◽  
Matt Francis ◽  
...  
Keyword(s):  
Production Systems ◽  
Energy Systems ◽  
Poor Performance ◽  
Alignment Error ◽  
Optical Modeling ◽  
The Past ◽  
Before And After ◽  
Alignment Strategy ◽  
Engine System

The proper alignment of facets on a dish engine system is critical to the performance of the system. Improper alignment can lead to poor performance and shortened life, through excessively high flux on the receiver surfaces, imbalanced power on multicylinder engines, and intercept losses at the aperture. Alignment approaches used in the past are time consuming field operations, typically taking 4–6 hours per dish with 40–80 facets on the dish. Production systems will need rapid, accurate alignment implemented in a fraction of an hour. In this paper, we present an AIMFAST characterization of a Stirling Energy Systems dish, before and after implementing an alignment using the AIMFAST software. The results of the alignment are correlated with fluxmapper measurements of the dish, and the improvement in the flux pattern projected to an engine receiver is calculated using Sandia’s CIRCE 2 dish optical modeling tool. The alignment substantially reduced the peak fluxes on the flat fluxmapper targets as well as the projection onto the receiver. The fluxmap images correlate well with the CIRCE projections of measured facet normals. In addition, we implemented automated actuation of the facet during alignment, improving the response and accuracy of the system, resulting in total dish alignments with under 0.1 mrad RMS alignment error. We also implemented an adaptive alignment strategy that varied the alignment based on the AIMFAST-measured facet shape.

scholarly journals AIMFAST: An Alignment Tool Based on Fringe Reflection Methods Applied To Dish Concentrators

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Charles E. Andraka ◽  
Julius Yellowhair ◽  
Kirill Trapeznikov ◽  
Jeff Carlson ◽  
Brian Myer ◽  
...  
Keyword(s):  
Real Time ◽  
Assembly Line ◽  
Production Systems ◽  
Poor Performance ◽  
Concentrated Solar Power ◽  
Fringe Analysis ◽  
The Past ◽  
Alignment Tool ◽  
Optical Alignment ◽  
Alignment Strategy

The proper alignment of facets on a dish engine concentrated solar power system is critical to the performance of the system. These systems are generally highly concentrating to produce high temperatures for maximum thermal efficiency so there is little tolerance for poor optical alignment. Improper alignment can lead to poor performance and shortened life through excessively high flux on the receiver surfaces, imbalanced power on multicylinder engines, and intercept losses at the aperture. Alignment approaches used in the past are time consuming field operations, typically taking 4–6 h per dish with 40–80 facets on the dish. Production systems of faceted dishes will need rapid, accurate alignment implemented in a fraction of an hour. In this paper, we present an extension to our Sandia Optical Fringe Analysis Slope Technique mirror characterization system that will automatically acquire data, implement an alignment strategy, and provide real-time mirror angle corrections to actuators or labor beneath the dish. The Alignment Implementation for Manufacturing using Fringe Analysis Slope Technique (AIMFAST) has been implemented and tested at the prototype level. In this paper we present the approach used in AIMFAST to rapidly characterize the dish system and provide near-real-time adjustment updates for each facet. The implemented approach can provide adjustment updates every 5 s, suitable for manual or automated adjustment of facets on a dish assembly line.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

An Electron Microscope Study of Interdiffusion and Compound Formation in Ta-Au Thin Films

1973 ◽  
Vol 31 ◽  
pp. 32-33 ◽  
Author(s):  
T. C. Tisone ◽  
S. Lau
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Thermally Grown Oxide ◽  
Ion Milling ◽  
Compound Formation ◽  
Technology Application ◽  
Transmission Electron ◽  
Before And After ◽  
Au Thin Films

In a study of the properties of a Ta-Au metallization system for thin film technology application, the interdiffusion between Ta(bcc)-Au, βTa-Au and Ta2M-Au films was studied. Considered here is a discussion of the use of the transmission electron microscope(TEM) in the identification of phases formed and characterization of the film microstructures before and after annealing.The films were deposited by sputtering onto silicon wafers with 5000 Å of thermally grown oxide. The film thicknesses were 2000 Å of Ta and 2000 Å of Au. Samples for TEM observation were prepared by ultrasonically cutting 3mm disks from the wafers. The disks were first chemically etched from the silicon side using a HNO3 :HF(19:5) solution followed by ion milling to perforation of the Au side.

Enlightening Symbols

2016 ◽  
Author(s):  
Joseph Mazur
Keyword(s):  
Sixteenth Century ◽  
Number System ◽  
Psychological Effects ◽  
Mathematical Notation ◽  
Rhetorical Style ◽  
The Past ◽  
Mathematical Symbols ◽  
Before And After ◽  
New Ideas ◽  
Different Cultures

While all of us regularly use basic mathematical symbols such as those for plus, minus, and equals, few of us know that many of these symbols weren't available before the sixteenth century. What did mathematicians rely on for their work before then? And how did mathematical notations evolve into what we know today? This book explains the fascinating history behind the development of our mathematical notation system. It shows how symbols were used initially, how one symbol replaced another over time, and how written math was conveyed before and after symbols became widely adopted. Traversing mathematical history and the foundations of numerals in different cultures, the book looks at how historians have disagreed over the origins of the number system for the past two centuries. It follows the transfigurations of algebra from a rhetorical style to a symbolic one, demonstrating that most algebra before the sixteenth century was written in prose or in verse employing the written names of numerals. It also investigates the subconscious and psychological effects that mathematical symbols have had on mathematical thought, moods, meaning, communication, and comprehension. It considers how these symbols influence us (through similarity, association, identity, resemblance, and repeated imagery), how they lead to new ideas by subconscious associations, how they make connections between experience and the unknown, and how they contribute to the communication of basic mathematics. From words to abbreviations to symbols, this book shows how math evolved to the familiar forms we use today.

PERBEDAAN FINANCIAL PERFORMANCE PASCA SECONDARY OFFERINGS

Wahana ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 41-49
Author(s):  
Djaja Perdana ◽  
Herbowo Herbowo
Keyword(s):  
Financial Performance ◽  
Stock Exchange ◽  
Hypothesis Test ◽  
Poor Performance ◽  
Rank Test ◽  
Growth Ratio ◽  
Significant Difference ◽  
Before And After ◽  
Signed Rank Test ◽  
Asset Turnover

This study aims to examine the differences in corporate financial performance before and after secondary offerings. The financial performance is proxied by WCR, DER, Solvency, ROA, ROE, Asset Turnover (ATO) and Growth ratio which representing the value of liquidity, financing, activity, performance and growth of the firm. The study involved 67 samples of the companies listed on the Indonesia Stock Exchange conducting secondary offerings during 2008-2013 period and selected through purposive random sampling method and using Financial Statement data from 2005-2016 period. Hypothesis test is performed using Wilcoxon Signed Rank test. The results of this study indicate that there is no significant difference in the ratio of Solvency, ROA and ROE between before and after secondary offerings, but there are significant differences in the ratio of WCR, DER, Asset Turnover and Growth. WCR ratio after secondary offerings increased, while DER ratio after secondary offerings decreased, the condition of both ratios showed better performance. While the indication of poor performance seen in decreasing asset turnover ratio and growth ratio.Keywords : agency theory, financial performance, secondary offerings

Density and morphological characterization of bacteria in integrated and exclusive production systems

2020 ◽  
Vol 13 (11) ◽  
pp. 1
Author(s):  
A. R. B. Zanco ◽  
A. Ferreira ◽  
G. C. M. Berber ◽  
E. N. Gonzaga ◽  
D. C. C. Sabino
Keyword(s):  
Bacterial Community ◽  
Rainy Season ◽  
Production Systems ◽  
Cropping System ◽  
Morphological Characterization ◽  
Native Forest ◽  
Exclusive Production ◽  
Colony Forming Units

The different integrated production systems can directly interfere with its bacterial community. The present study aimed to assess density, bacterial diversity and the influence of dry and rainy season in different integrated and an exclusive production system. The fallow and a native forest area was assessed to. Samples were collected in 2012 March and September. The isolation were carried out into Petri dishes containing DYGS medium. The number of colony forming units (CFU) was counted after 48 hours and. The bacterial density ranged between 106 and 107 CFU g-1 soil. The crop system affected the dynamics of the bacterial community only in the rainy season. The rainy season showed greater density of total bacteria when compared to the dry period regardless of the cropping system. The dendrograms with 80 % similarity showed thirteen and fourteen groups in the rainy and dry seasons. Isolates with the capacity to solubilize phosphate in vitro were obtained from all areas in the two seasons, but this feature has been prevalent in bacteria isolated during the rainy season

‘The Wretch of To-day, may be happy To-morrow’

2017 ◽  
Author(s):  
Sarah Lloyd
Keyword(s):  
Emotional Experience ◽  
The Past

This chapter explores what we can know about the conceptualization and representation of by poorer Britons. It draws on ‘pauper letters’ to parish authorities, written tactically, and on autobiographies and letters composed by the relatively poor, noting echoes of the characterization of happiness by elite social commentators. It draws attention to a growing interest (linked to the development of the concept of nostalgia) in the emotional charge that could be derived from reflection on emotional experience as people contrasted past happiness with present misery, or vice versa. While reading such accounts may lead us to think that we are penetrating the interior lives of marginal people in the past, Lloyd suggests that our response is probably coloured by the fact that we are heirs to these ways of conceptualizing and representing experience. We need to work harder to glean insight from earlier ways of representing happiness and suffering.

The Problem of Divine Hiddenness

2018 ◽  
Author(s):  
Michael C. Rea
Keyword(s):  
Problem Of Evil ◽  
Philosophical Discussion ◽  
Detailed Characterization ◽  
The Past ◽  
Divine Hiddenness ◽  
The Problem Of Evil ◽  
The Relationship

This chapter provides a detailed characterization of the various meanings of the term “divine hiddenness,” carefully and rigorously articulates the version of the problem of divine hiddenness that has dominated contemporary philosophical discussion for the past twenty-five years, and then explains the relationship between that problem and the problem of evil.

scholarly journals Environmental assessment of the Tung cultivation through life cycle analysis

2014 ◽  
Vol 3 (1) ◽  
pp. 70 ◽  
Author(s):  
Marcelo Bern�l ◽  
Rosana Schneider ◽  
�nio Machado
Keyword(s):  
Life Cycle ◽  
Production Systems ◽  
Life Cycle Management ◽  
Assessment Method ◽  
Agroforestry Systems ◽  
Family Farms ◽  
Conventional Agriculture ◽  
The Past ◽  
Ecosystem Changes ◽  
Poor Soil

Over the past few decades, conventional agriculture has been facing serious crises caused by numerous factors, including poor soil management and the excessive application of pesticides. Thus, alternative production systems have been developed, including agroforestry systems, especially those that produce both energy and food. The objective of this study was to environmentally evaluate the culture of Aleurites fordii Hemls. (Tung) using the Life Cycle Assessment method with the SimaPro 7.3.2 software. The results revealed that in family farms that use less mechanization to harvest crops, the primary category of environmental impact was land use, which included the removal of animal and vegetable species and ecosystem changes. The full impact of this category was 1741.21 m2yr PDF (potentially disappeared fraction). Subsequently, prognostics were established for the reduction of such impacts, and we conclude that Tung has a high potential for agricultural installation with high responsibility to the environment. Keywords: Environmental factors, Aleurites fordii Hemls, Life Cycle Management, Tung.

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