scholarly journals J-PLUS: photometric calibration of large-area multi-filter surveys with stellar and white dwarf loci

2019 ◽  
Vol 631 ◽  
pp. A119 ◽  
Author(s):  
C. López-Sanjuan ◽  
J. Varela ◽  
D. Cristóbal-Hornillos ◽  
H. Vázquez Ramió ◽  
J. M. Carrasco ◽  
...  
Keyword(s):  
White Dwarf ◽  
Zero Point ◽  
Optical Filters ◽  
Calibration Method ◽  
Large Area ◽  
Photometric Calibration ◽  
The Absolute ◽  
Definition Of ◽  
Photometric Solution ◽  
Flux Calibration

Aims. We present the photometric calibration of the 12 optical passbands observed by the Javalambre Photometric Local Universe Survey (J-PLUS). Methods. The proposed calibration method has four steps: (i) definition of a high-quality set of calibration stars using Gaia information and available 3D dust maps; (ii) anchoring of the J-PLUS gri passbands to the Pan-STARRS photometric solution, accounting for the variation in the calibration with the position of the sources on the CCD; (iii) homogenization of the photometry in the other nine J-PLUS filters using the dust de-reddened instrumental stellar locus in (𝒳 − r) versus (g − i) colours, where 𝒳 is the filter to calibrate. The zero point variation along the CCD in these filters was estimated with the distance to the stellar locus. Finally, (iv) the absolute colour calibration was obtained with the white dwarf locus. We performed a joint Bayesian modelling of 11 J-PLUS colour–colour diagrams using the theoretical white dwarf locus as reference. This provides the needed offsets to transform instrumental magnitudes to calibrated magnitudes outside the atmosphere. Results. The uncertainty of the J-PLUS photometric calibration, estimated from duplicated objects observed in adjacent pointings and accounting for the absolute colour and flux calibration errors, are ∼19 mmag in u, J0378, and J0395; ∼11 mmag in J0410 and J0430; and ∼8 mmag in g, J0515, r, J0660, i, J0861, and z. Conclusions. We present an optimized calibration method for the large-area multi-filter J-PLUS project, reaching 1–2% accuracy within an area of 1022 square degrees without the need for long observing calibration campaigns or constant atmospheric monitoring. The proposed method will be adapted for the photometric calibration of J-PAS, that will observe several thousand square degrees with 56 narrow optical filters.

scholarly journals The Nature of Heat and the Absolute Zero Temperature

2020 ◽  
Vol 10 (4) ◽  
pp. 35-39
Author(s):  
Xingwu Xu
Keyword(s):  
Black Hole ◽  
Basic Concept ◽  
Zero Point ◽  
Vacuum Pump ◽  
Absolute Zero ◽  
Zero Temperature ◽  
Point Energy ◽  
Subatomic Particles ◽  
The Absolute ◽  
Definition Of

This paper starts with the most basic concept of heat as well as temperature, historically investigates the understanding of the nature of heat, the conclusion is that the nature of heat is just a form of energy. This energy includes the zero-point energy providing by the motion of all subatomic particles. The new definition of temperature should be that it is the degree of matter’s motion. These matters include subatomic particles. Therefore, at the absolute zero, the “temperature” should still exist. On accounting of no subatomic particles’ motion in the singularity of the black hole, I proved that there exists a new absolute zero temperature there, which is lower than the existing one. The theory proposed in this paper can be supported by following means: measuring the temperature inside the black hole, letting electrons stop moving, and designing a Casimir vacuum pump.

scholarly journals The Gaia spectrophotometric standard stars survey - IV. Results of the absolute photometry campaign.

2020 ◽  
Author(s):  
G Altavilla ◽  
S Marinoni ◽  
E Pancino ◽  
S Galleti ◽  
M Bellazzini ◽  
...  
Keyword(s):  
Photometric Calibration ◽  
Absolute Flux ◽  
Current Limit ◽  
Calibration Accuracy ◽  
The Absolute ◽  
Sky Conditions ◽  
Stars Survey ◽  
Flux Calibration

Abstract We present Johnson-Kron-Cousins BVRI photometry of 228 candidate spectrophotometric standard stars for the external (absolute) flux calibration of Gaia data. The data were gathered as part of a ten-year observing campaign with the goal of building the external grid of flux standards for Gaia and we obtained absolute photometry, relative photometry for constancy monitoring, and spectrophotometry. Preliminary releases of the flux tables were used to calibrate the first two Gaia releases. This paper focuses on the imaging frames observed in good sky conditions (about 9100). The photometry will be used to validate the ground-based flux tables of the Gaia spectrophotometric standard stars and to correct the spectra obtained in non-perfectly photometric observing conditions for small zeropoint variations. The absolute photometry presented here is tied to the Landolt standard stars system to ≃1 per cent or better, depending on the photometric band. Extensive comparisons with various literature sources show an overall ≃1 per cent agreement, which appears to be the current limit in the accuracy of flux calibrations across various samples and techniques in the literature. The Gaia photometric precision is presently of the order of 0.1 per cent or better, thus various ideas for the improvement of photometric calibration accuracy are discussed.

Kant’s Metaphilosophy

2021 ◽  
Vol 4 (1) ◽  
pp. 292-310
Author(s):  
Michael Lewin
Keyword(s):  
Social Practice ◽  
Scientific Concept ◽  
Demarcation Criterion ◽  
The Absolute ◽  
Definition Of

Abstract While the term “metaphilosophy” enjoys increasing popularity in Kant scholarship, it is neither clear what distinguishes a metaphilosophical theory from a philosophical one nor to what extent Kant’s philosophy contains metaphilosophical views. In the first part of the article, I will introduce a demarcation criterion and show how scholars fall prey to the fallacy of extension confusing Kant’s philosophical theories with his theories about philosophy. In the second part, I will analyze eight elements for an “imperfect definition” (KrV A731/B759) of philosophy outlining the scope of Kant’s explicit metaphilosophy against the backdrop of recent metaphilosophical research: (i) scientific concept of philosophy, (ii) philosophy as an activity, (iii) worldly concept, (iv) philosophy as a (proper and improper) science, (v) philosophy as an architectonic idea (archetype and ectypes), (vi) philosophy as a social practice and the appropriate holding-to-be-true (one or many true philosophies?), (vii) reason as the absolute condition and subject of philosophy, and (viii) methodology of philosophy. I will put these elements together for an attempt to give an imperfect definition of philosophy – something that Kant promised but never did – in the conclusion.

scholarly journals Three-tiered score for Ki-67 and p16ink4a improves accuracy and reproducibility of grading CIN lesions

2018 ◽  
Vol 71 (11) ◽  
pp. 981-988 ◽  
Author(s):  
Marjolein van Zummeren ◽  
Annemiek Leeman ◽  
Wieke W Kremer ◽  
Maaike C G Bleeker ◽  
David Jenkins ◽  
...  
Keyword(s):  
Management Strategies ◽  
Intraepithelial Neoplasia ◽  
Reference Standard ◽  
Ki 67 ◽  
Papillomavirus Infection ◽  
Cumulative Score ◽  
The Absolute ◽  
Definition Of ◽  
New Biomarkers ◽  
Tissue Specimens

AimsTo investigate the accuracy and reproducibility of a scoring system for cervical intraepithelial neoplasia (CIN1–3) based on immunohistochemical (IHC) biomarkers Ki-67 and p16ink4a.Methods115 cervical tissue specimens were reviewed by three expert gynaecopathologists and graded according to three strategies: (1) CIN grade based on H&E staining only; (2) immunoscore based on the cumulative score of Ki-67 and p16ink4a only (0–6); and (3) CIN grade based on H&E supported by non-objectified IHC 2 weeks after scoring 1 and 2. The majority consensus diagnosis of the CIN grade based on H&E supported by IHC was used as the Reference Standard. The proportion of test positives (accuracy) and the absolute agreements across pathologists (reproducibility) of the three grading strategies within each Reference Standard category were calculated.ResultsWe found that immunoscoring with positivity definition 6 yielded the highest proportion of test positives for Reference Standard CIN3 (95.5%), in combination with the lowest proportion of test positives in samples with CIN1 (1.8%). The proportion of test positives for CIN3 was significantly lower for sole H&E staining (81.8%) or combined H&E and IHC grading (84.8%) with positivity definition ≥CIN3. Immunoscore 6 also yielded high absolute agreements for CIN3 and CIN1, but the absolute agreement was low for CIN2.ConclusionsThe higher accuracy and reproducibility of the immunoscore opens the possibility of a more standardised and reproducible definition of CIN grade than conventional pathology practice, allowing a more accurate comparison of CIN-based management strategies and evaluation of new biomarkers to improve the understanding of progression of precancer from human papillomavirus infection to cancer.

scholarly journals Analysis of full disc Ca II K spectroheliograms

2018 ◽  
Vol 609 ◽  
pp. A92 ◽  
Author(s):  
Theodosios Chatzistergos ◽  
Ilaria Ermolli ◽  
Sami K. Solanki ◽  
Natalie A. Krivova
Keyword(s):  
Synthetic Data ◽  
Calibration Method ◽  
Poor Quality ◽  
Average Error ◽  
Photometric Calibration ◽  
Solar Observations ◽  
Relative Errors ◽  
Long Term Variations ◽  
The Ideal

Context. Historical Ca II K spectroheliograms (SHG) are unique in representing long-term variations of the solar chromospheric magnetic field. They usually suffer from numerous problems and lack photometric calibration. Thus accurate processing of these data is required to get meaningful results from their analysis. Aims. In this paper we aim at developing an automatic processing and photometric calibration method that provides precise and consistent results when applied to historical SHG. Methods. The proposed method is based on the assumption that the centre-to-limb variation of the intensity in quiet Sun regions does not vary with time. We tested the accuracy of the proposed method on various sets of synthetic images that mimic problems encountered in historical observations. We also tested our approach on a large sample of images randomly extracted from seven different SHG archives. Results. The tests carried out on the synthetic data show that the maximum relative errors of the method are generally <6.5%, while the average error is <1%, even if rather poor quality observations are considered. In the absence of strong artefacts the method returns images that differ from the ideal ones by <2% in any pixel. The method gives consistent values for both plage and network areas. We also show that our method returns consistent results for images from different SHG archives. Conclusions. Our tests show that the proposed method is more accurate than other methods presented in the literature. Our method can also be applied to process images from photographic archives of solar observations at other wavelengths than Ca II K.

scholarly journals Virtual Calibration Method for Diesel Engine by Software in The Loop Techniques

2019 ◽  
Vol 16 (3) ◽  
pp. 6940-6957
Author(s):  
M. C. Cameretti ◽  
E. Landolfi ◽  
T. Tesone ◽  
A. Caraceni
Keyword(s):  
Diesel Engine ◽  
Fuel Economy ◽  
Engine Performance ◽  
Control Unit ◽  
Calibration Method ◽  
Pollutant Emissions ◽  
Engine Control ◽  
Start Of Injection ◽  
Definition Of ◽  
Valid Solution

The calibration of the engine control unit is increased for the development of the whole automotive system. The aim is to calibrate the electronic engine control to match the decreasing emission requirements and increasing fuel economy demands. The reduction of the number of tests on vehicles represents one of the most important requirements for increasing efficiency of the engine calibration process. However, the definition of the design of experiment is not straightforward because the data is not known beforehand, so it is difficult to process and analyse this data to achieve a globally valid model. To reduce time effort and costs the virtual calibration can be a valid solution. This procedure is called software in the loop (SIL) calibration able to develop a process to systematically identify the optimal balance of engine performance, emissions and fuel economy. In this work, a virtual calibration methodology is presented by using a two-stage model to get minimum exhaust emissions of a diesel engine. The data used are from a GT-Power model of a 3L supercharged diesel engine. The model is able to calculate the engine emissions for different engine parameters (such as the start of injection, EGR fraction and rail pressure) and from optimisation process, new injection start maps that reduce pollutant emissions are created.

37. Absolute grounds for refusal

2018 ◽  
Author(s):  
L. Bently ◽  
B. Sherman ◽  
D. Gangjee ◽  
P. Johnson
Keyword(s):  
Public Policy ◽  
Trade Mark ◽  
The European Union ◽  
Bad Faith ◽  
Trade Marks ◽  
The Public ◽  
The Absolute ◽  
Definition Of ◽  
Absolute Grounds For Refusal ◽  
Trade Mark Registration

This chapter examines the ‘absolute’ grounds for refusing to register a trade mark as set out in section 3 of the Trade Marks Act 1994, Article 3 of the Trade Marks Directive, and Article 7 of the European Union Trade Mark Regulation (EUTMR). It first looks at the reasons for denying an application for trade mark registration before analysing the absolute grounds for refusal, which can be grouped into three general categories: whether the sign falls within the statutory definition of a trade mark found in sections 1(1) and 3(1)(a) and (2) of the Trade Marks Act 1994; whether trade marks are non-distinctive, descriptive, and generic; and whether trade marks are contrary to public policy or morality, likely to deceive the public, prohibited by law, or if the application was made in bad faith. Provisions for specially protected emblems are also considered.

scholarly journals A Normal Sensor Calibration Method Based on an Extended Kalman Filter for Robotic Drilling

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3485 ◽  
Author(s):  
Dongdong Chen ◽  
Peijiang Yuan ◽  
Tianmiao Wang ◽  
Ying Cai ◽  
Haiyang Tang
Keyword(s):  
Kalman Filter ◽  
Laser Beam ◽  
Extended Kalman Filter ◽  
Zero Point ◽  
Calibration Method ◽  
Sensor Calibration ◽  
Beam Direction ◽  
Displacement Sensors ◽  
Robotic Drilling ◽  
Drilling System

To enhance the perpendicularity accuracy in the robotic drilling system, a normal sensor calibration method is proposed to identify the errors of the zero point and laser beam direction of laser displacement sensors simultaneously. The procedure of normal adjustment of the robotic drilling system is introduced firstly. Next the measurement model of the zero point and laser beam direction on a datum plane is constructed based on the principle of the distance measurement for laser displacement sensors. An extended Kalman filter algorithm is used to identify the sensor errors. Then the surface normal measurement and attitude adjustments are presented to ensure that the axis of the drill bit coincides with the normal at drilling point. Finally, simulations are conducted to study the performance of the proposed calibration method and experiments are carried out on a robotic drilling system. The simulation and experimental results show that the perpendicularity of the hole is within 0.2°. They also demonstrate that the proposed calibration method has high accuracy of parameter identification and lays a basis for high-precision perpendicularity accuracy of drilling in the robotic drilling system.

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