Exoplanet Ephemeris Maintenance using Ground- and Space-based Telescopes

2020 ◽  
Author(s):  
Hamish Caines ◽  
Marco Rocchetto ◽  
Giorgio Savini
Keyword(s):  
Diurnal Cycle ◽  
Orbital Period ◽  
Precise Knowledge ◽  
Robotic Telescopes ◽  
Time Required ◽  
Atmospheric Distortion ◽  
Do So

<p>Ariel will require precise knowledge of the transit timings for all of its targets. However, the precision we have for each target will degrade significantly over the 8 years until launch, in some cases to the point where the error exceeds the duration of the transit itself. The knowledge of these transits would then be deemed “lost”. To counteract this, and in effect “reset the clock”, we aim to use the Telescope Live network of robotic telescopes to observe such targets. With 1000 targets and an average orbital period of the order of days, the size and usage of the network required needs to be quantified. Here we present results from simulations of these observations for a variety of telescope networks of varying sizes, the number of targets that can be successfully constrained, and the amount of observing time required to do so. From these results we can conclude that a ground-based telescope network containing as few as 2 telescopes of 0.6m aperture can constrain over 60% of the targets with transit depths observable from the ground. A fraction of these exoplanets are difficult to observe with ground-based telescopes as they either have transit depths too shallow to detect due to atmospheric distortion and/or their transit durations are comparable to the length of a night, reducing the probability of observable transits occurring. Such targets would benefit from supplementary observations from space-based observatories, as these do not suffer from either atmospheric distortion or limits on observing time due to Earth’s diurnal cycle.</p>

Metrics for Evaluating and Optimizing the Barrier and Time to Reverse Engineer a Product

2009 ◽  
Author(s):  
Stephen P. Harston ◽  
Christopher A. Mattson
Keyword(s):  
Reverse Engineering ◽  
Optimization Techniques ◽  
Original Design ◽  
Reverse Engineer ◽  
Innovative Products ◽  
Industry Practice ◽  
Time Required ◽  
Numerical Representations ◽  
Insight Into ◽  
Do So

Reverse engineering, defined as extracting information about a product from the product itself, is a common industry practice for gaining insight into innovative products. Both the original designer and those reverse engineering the original design can benefit from estimating the time and barrier to reverse engineer a product. This paper presents a set of metrics and parameters that can be used to calculate the barrier to reverse engineer any product as well as the time required to do so. To the original designer, these numerical representations of the barrier and time can be used to strategically identify and improve product characteristics so as to increase the difficulty and time to reverse engineer them. As the metrics and parameters developed in this paper are quantitative in nature, they can also be used in conjunction with numerical optimization techniques, thereby enabling products to be developed with a maximum reverse engineering barrier and time — at a minimum development cost. On the other hand, these quantitative measures enable competitors who reverse engineer original designs to focus their efforts on products that will result in the greatest return on investment.

Metrics for Evaluating the Barrier and Time to Reverse Engineer a Product

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Stephen P. Harston ◽  
Christopher A. Mattson
Keyword(s):  
Reverse Engineering ◽  
Optimization Techniques ◽  
Original Design ◽  
Reverse Engineer ◽  
Innovative Products ◽  
Industry Practice ◽  
Time Required ◽  
Numerical Representations ◽  
Insight Into ◽  
Do So

Reverse engineering, defined as extracting information about a product from the product itself, is a common industry practice for gaining insight into innovative products. Both the original designer and those reverse engineering the original design can benefit from estimating the time and barrier to reverse engineer a product. This paper presents a set of metrics and parameters that can be used to calculate the barrier to reverse engineer any product, as well as the time required to do so. To the original designer, these numerical representations of the barrier and time can be used to strategically identify and improve product characteristics so as to increase the difficulty and time to reverse engineer them. As the metrics and parameters developed in this paper are quantitative in nature, they can also be used in conjunction with numerical optimization techniques, thereby enabling products to be developed with a maximum reverse engineering barrier and time—at a minimum development cost. On the other hand, these quantitative measures enable competitors who reverse engineer original designs to focus their efforts on products that will result in the greatest return on investment.

scholarly journals PATMOS-x: Results from a Diurnally Corrected 30-yr Satellite Cloud Climatology

2013 ◽  
Vol 26 (2) ◽  
pp. 414-425 ◽  
Author(s):  
Michael J. Foster ◽  
Andrew Heidinger
Keyword(s):  
Diurnal Cycle ◽  
Minimum Length ◽  
The Stability ◽  
Time Required ◽  
The Tropics ◽  
Ice Water ◽  
Diurnal Correction ◽  
Very High ◽  
Good Agreement

Abstract Satellite drift is a historical issue affecting the consistency of those few satellite records capable of being used for studies on climate time scales. Here, the authors address this issue for the Pathfinder Atmospheres Extended (PATMOS-x)/Advanced Very High Resolution Radiometer (AVHRR) cloudiness record, which spans three decades and 11 disparate sensors. A two-harmonic sinusoidal function is fit to a mean diurnal cycle of cloudiness derived over the course of the entire AVHRR record. The authors validate this function against measurements from Geostationary Operational Environmental Satellite (GOES) sensors, finding good agreement, and then test the stability of the diurnal cycle over the course of the AVHRR record. It is found that the diurnal cycle is subject to some interannual variability over land but that the differences are somewhat offset when averaged over an entire day. The fit function is used to generate daily averaged time series of ice, water, and total cloudiness over the tropics, where it is found that the diurnal correction affects the magnitude and even the sign of long-term cloudiness trends. A statistical method is applied to determine the minimum length of time required to detect significant trends, and the authors find that only recently have they begun generating satellite records of sufficient length to detect trends in cloudiness.

Modern interpretation of Pindar: the Second Pythian and Seventh Nemean Odes

1973 ◽  
Vol 93 ◽  
pp. 109-137 ◽  
Author(s):  
Hugh Lloyd-Jones
Keyword(s):  
Point Of View ◽  
Ancient World ◽  
The Other ◽  
Inaugural Lecture ◽  
Great Scholar ◽  
Time Required ◽  
Do So

Since I was taken, thirty-five years ago, to hear E. R. Dodds lecture on the Bacchae, his work has been one of my chief sources of inspiration. My Sather Lectures form a kind of commentary on his; and if I sometimes disagree with him, or see things from a different point of view, that will not prevent the understanding reader from seeing how greatly I admire him and how much my work owes to his. His inaugural lecture at Oxford was called ‘Humanism and Technique in Greek Studies’; and no great scholar of our time, except perhaps Rudolf Pfeiffer, has kept so perfect a balance between the two. In that lecture Dodds, as the circumstances of the time required, pleaded for more attention to the content, as against the form, of ancient writings; and throughout his career he has applied his masterly technique to just those problems of the ancient world which are of most interest and importance to the modern. But he has always borne in mind that a scholar who hopes to throw light upon such problems must do all he can to master the technique of his profession. Both in his humanism and in his technique, he offers an example from which all classical scholars of our time can profit.To me Pindar seems one of the greatest Greek and also one of the greatest European poets. But some would dispute this proposition; and I believe that many even of those who would assent to it in reality admire him less than other great poets who seem to me to be his equals. There are two main reasons why Pindar has received less than justice. One is that he is believed to have a narrow and restricted outlook, which is often unfavourably compared with that of the great tragedians; the other is that he is difficult. The question of whether Pindar's outlook is narrow I shall treat comparatively briefly here; I shall not try here to describe that outlook at any length, though I may do so later. In comparing it with that of the tragedians, I shall be able to save space because of having already, in my book The Justice of Zeus, written about the Weltanschauung of the early Greek poets. Next, I shall pass to the difficulties which Pindar presents to modern readers. The difficulty with which I shall be most concerned will be that of eluding the dangers inherent in the romantic and historicist approach to Pindar which until eleven years ago was adopted in virtually all modern treatments and which still comes most naturally to most readers, including several distinguished scholars.

scholarly journals CHANGES IN THE NUMBER OF IDEAS DEPENDING ON TIME WHEN CONDUCTING SCIENTIFIC CREATIVITY ACTIVITIES

2015 ◽  
Vol 14 (4) ◽  
pp. 448-459
Author(s):  
Daehyeok Kang ◽  
Jongwon Park ◽  
Hanghwa Hong
Keyword(s):  
Middle Schools ◽  
Gifted Education ◽  
Gifted Students ◽  
School Science ◽  
Minimal Amount ◽  
Scientific Creativity ◽  
Science Scores ◽  
Time Required ◽  
Creativity Task ◽  
Do So

Teaching creativity is one of the major goals of science class. This study examined how much time is necessary to conduct a scientific creativity task requiring fluency in middle schools. To accomplish this, 76 and 45 scientifically gifted and ordinary students respectively generated as many ideas as possible for the creativity task. The results revealed that ordinary students spent, on average, approximately 20 minutes to generate 3.49 ideas per student. However, gifted students concentrated on the task for a longer time (roughly 60 minutes), and consequently generated greater (11.53) and more elaborate ideas. In comparing the ordinary students’ fluency with their school science scores, no relationship was found between them. This indicates that only teaching science cannot guarantee the development of creativity. Therefore, it is concluded that teaching fluency in middle schools is necessary and can possibly encourage creativity, provided that teachers can secure a minimal amount of time required to do so. Finally, the limitations of this study and further studies are discussed. Key words: fluency, gifted education, scientific creativity, teaching creativity.

scholarly journals An experimental characterization of workers’ behavior and accuracy in crowdsourced tasks

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252604
Author(s):  
Evgenia Christoforou ◽  
Antonio Fernández Anta ◽  
Angel Sánchez
Keyword(s):  
Amazon Mechanical Turk ◽  
Wrong Answer ◽  
Control Techniques ◽  
Different Types ◽  
Series Of Experiments ◽  
Time Required ◽  
Short Time ◽  
Do So

Crowdsourcing systems are evolving into a powerful tool of choice to deal with repetitive or lengthy human-based tasks. Prominent among those is Amazon Mechanical Turk, in which Human Intelligence Tasks, are posted by requesters, and afterwards selected and executed by subscribed (human) workers in the platform. Many times these HITs serve for research purposes. In this context, a very important question is how reliable the results obtained through these platforms are, in view of the limited control a requester has on the workers’ actions. Various control techniques are currently proposed but they are not free from shortcomings, and their use must be accompanied by a deeper understanding of the workers’ behavior. In this work, we attempt to interpret the workers’ behavior and reliability level in the absence of control techniques. To do so, we perform a series of experiments with 600 distinct MTurk workers, specifically designed to elicit the worker’s level of dedication to a task, according to the task’s nature and difficulty. We show that the time required by a worker to carry out a task correlates with its difficulty, and also with the quality of the outcome. We find that there are different types of workers. While some of them are willing to invest a significant amount of time to arrive at the correct answer, at the same time we observe a significant fraction of workers that reply with a wrong answer. For the latter, the difficulty of the task and the very short time they took to reply suggest that they, intentionally, did not even attempt to solve the task.

Holding replication studies to mainstream standards of evidence

2018 ◽  
Vol 41 ◽  
Author(s):  
Duane T. Wegener ◽  
Leandre R. Fabrigar
Keyword(s):  
Replication Studies ◽  
Replication Research ◽  
Standards Of Evidence ◽  
Do So

AbstractReplications can make theoretical contributions, but are unlikely to do so if their findings are open to multiple interpretations (especially violations of psychometric invariance). Thus, just as studies demonstrating novel effects are often expected to empirically evaluate competing explanations, replications should be held to similar standards. Unfortunately, this is rarely done, thereby undermining the value of replication research.

The Eclipsing Binary WX Eridani

1979 ◽  
Vol 46 ◽  
pp. 385
Author(s):  
M.B.K. Sarma ◽  
K.D. Abhankar
Keyword(s):  
Light Curve ◽  
Spectral Type ◽  
Orbital Period ◽  
Primary Component ◽  
Light Curves ◽  
Absorption Feature ◽  
Primary Star ◽  
Eclipsing Binary ◽  
The Times ◽  
Phase Angles

AbstractThe Algol-type eclipsing binary WX Eridani was observed on 21 nights on the 48-inch telescope of the Japal-Rangapur Observatory during 1973-75 in B and V colours. An improved period of P = 0.82327038 days was obtained from the analysis of the times of five primary minima. An absorption feature between phase angles 50-80, 100-130, 230-260 and 280-310 was present in the light curves. The analysis of the light curves indicated the eclipses to be grazing with primary to be transit and secondary, an occultation. Elements derived from the solution of the light curve using Russel-Merrill method are given. From comparison of the fractional radii with Roche lobes, it is concluded that none of the components have filled their respective lobes but the primary star seems to be evolving. The spectral type of the primary component was estimated to be F3 and is found to be pulsating with two periods equal to one-fifth and one-sixth of the orbital period.

RSCVn Stars in the Southern Hemisphere

1979 ◽  
Vol 46 ◽  
pp. 371-384 ◽  
Author(s):  
J.B. Hearnshaw
Keyword(s):  
Light Curve ◽  
Southern Hemisphere ◽  
Orbital Period ◽  
Binary Stars ◽  
Small Amplitude ◽  
Light Variation ◽  
Orbital Phase

RSCVn stars are fully detached binary stars which show intrinsic small amplitude (up to 0.3 amplitude peak-to-peak) light variations, as well as, in most of the known cases, eclipses. The spectra are F to G, IV to V for the hotter component and usually KOIV for the cooler. They are also characterised by abnormally strong H and K emission from the cooler star, or, occasionally, from both components. The orbital and light curve periods are in the range 1 day to 2 weeks. An interesting feature is the migration of the light variations to earlier orbital phase, as the light variation period is shorter than the orbital period by a few parts in 10+4to a few parts in 10+3.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

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