- Don't stop checking and rechecking evidence until you are satisfied.
Friday, 1 April 2016
Friday, 30 October 2015
Turning "algae from trash into treasure"
Convert harmful algae into Na-ion battery electrodes
http://alternativeenergy.electronicspecifier.com/around-the-industry/convert-harmful-algae-into-na-ion-battery-electrodes
29th October 2015
Saturday, 25 July 2015
The Science of Al-Biruni
The Science of Al-Biruni
Al-Biruni (973-1048) was one of the greatest scientists of all times.
He was an astronomer, mathematician and philosopher, and studied
physics and natural sciences. In this paper, we will discuss
some of his experimental methods and some instruments he used.
On the Role of Tsallis Entropy in Image Processing
International Scientific Research Journal ~ ISSN 2412-026X
Link to the Journal IRJ.Science
On the Role of Tsallis Entropy in Image Processing
On the Role of Tsallis Entropy in Image Processing
In image processing, the maximum entropy principle is generally recognized as having a relevant role in the initial part of image elaboration. The first step of processing in fact, sees the entropy used to determine the segmentation of the image, that is, used to determine objects and background in it. Different entropy formulations are available to this purpose, but the most prominent in recent publications is that of the Tsallis non-extensive entropy. Here, we survey some main methods that are using this entropy and the related literature, in particular that reporting the researches concerning medical image processing.
Keywords: Tsallis Entropy; Image Processing; Image Segmentation; Image Thresholding; Medical Image Processing
DOI: 10.18483/IRJSci.79
Link to the paper http://www.irj.science/pub/article/79DOI: 10.18483/IRJSci.79
Wednesday, 5 November 2014
Carbon Dioxide Concentration and Emissions in Atmosphere: Trends and Recurrence Plots
The increase of carbon dioxide concentration in atmosphere, due to anthropogenic emissions, is almost generally considered as responsible of global climate changes. We show some data of CO2 concentration and its emission in atmosphere, using the recurrence plots to enhance the visualization of their trends. See more at: http://www.ijsciences.com/pub/article/582#sthash.L4dBnzsh.dpuf
See more at: http://www.ijsciences.com/pub/article/582#sthash.L4dBnzsh.dpuf
Data of CO2 concentration in atmosphere, from [1]. The range is from January 1958 to October 2014. In the image we see the recurrence plot. The global annual mean concentration of CO2 in the atmosphere is currently rising at a rate of approximately 2 ppm/year and accelerating [1]. This acceleration is shown by the recurrence plot, where colours are narrowing towards the diagonal line.
[1] Tans, P. & Keeling R. (2014). Trends in atmospheric carbon dioxide, Oceanic & Atmospheric Administration (NOAA). At www.esrl.noaa.gov/ gmd/ ccgg/ trends/
About 1970, the oil production and import of US had a sharp peak (data from Ref.12). Note how the corresponding recurrence plot evidences this peak.
[12] Vv.Aa. (2014). U.S. Energy Information Administration (EIA), at www.eia.gov/petroleum/
Tuesday, 15 July 2014
The Thegns of Mercia: Did Anglo-Saxons use crystal lenses?
The Thegns of Mercia: Did Anglo-Saxons use crystal lenses?
Very interesting post. See in particular the "Greek lens, as seen recently at Rhodes"
Very interesting post. See in particular the "Greek lens, as seen recently at Rhodes"
Saturday, 19 April 2014
Robert Grosseteste, De Luce, On Light
Robert Grosseteste's Thought on Light and Form of the World
A.C. Sparavigna
THE INTERNATIONAL JOURNAL OF SCIENCES
2014, Volume: 3, Numero: 4, Pagine: pp. 54-62
ISSN: 2305-3925
Abstract: Robert Grosseteste was one of the most prominent thinkers of the Thirteenth Century. Philosopher and scientist, he proposed a metaphysics based on the propagation of light. In this framework, he gave a cosmology too. Here we will discuss the treatise where Grosseteste proposed it, that entitled 'De luce, seu de incohatione formarum', 'On Light and the Beginning of Forms'
Parole chiave: medieval science, cosmogony, history of physics, history of science, robert grosseteste, big bang, cosmology
http://www.ijsciences.com/pub/article/486
You can find some papers of mine about Robert Grosseteste at this link:
http://www.ijsciences.com/pub/author/342
A.C. Sparavigna
THE INTERNATIONAL JOURNAL OF SCIENCES
2014, Volume: 3, Numero: 4, Pagine: pp. 54-62
ISSN: 2305-3925
Abstract: Robert Grosseteste was one of the most prominent thinkers of the Thirteenth Century. Philosopher and scientist, he proposed a metaphysics based on the propagation of light. In this framework, he gave a cosmology too. Here we will discuss the treatise where Grosseteste proposed it, that entitled 'De luce, seu de incohatione formarum', 'On Light and the Beginning of Forms'
Parole chiave: medieval science, cosmogony, history of physics, history of science, robert grosseteste, big bang, cosmology
http://www.ijsciences.com/pub/article/486
You can find some papers of mine about Robert Grosseteste at this link:
http://www.ijsciences.com/pub/author/342
Friday, 18 April 2014
Wednesday, 9 April 2014
Robert Grosseteste and his Big Bang
"From Rome to the Antipodes: The Medieval Form of the World," International Journal of Literature and Arts . Vol. 1, No. 2, 2013, pp. 16-25. doi:10.11648/j.ijla.20130102.11
9. Grosseteste and the Sphere of Light
Robert Grosseteste (1175-1253) was an English philosopher who became the Bishop of Lincoln. As a scientist he had a quite important role in the medieval school of Oxford [32]. In his works, in particular in the commentaries of Aristotle’s philosophy, Grosseteste devised a scientific method. From particular observations, we can find a universal law, and then, from these laws we can predict some peculiar cases. Grosseteste called this “resolution and composition” [33]. As a consequence, Grosseteste tells that physics needs the ‘experimentum’, that is, a proof from experience. These ideas were a prelude for the Galilean science in the 17th century [34]. The method of “resolution and composition” was applied to geometry and optics. Moreover, optics is described by geometry, because optics depends on geometry. As a conclusion, Grosseteste argued that mathematics was the highest science, basis for all others. Here we see that he understood the necessity to describe the physical phenomena in a mathematic formalism. Grosseteste believed that at the beginning of times, it wasthe light to move the universe. In his “De Luce”, Grosseteste explains the origin of the world. God created matter and light together in a point. Due to its nature the light propagated isotropically in all directions. It immediately became a sphere and, accordingly, dragged by the light, the matter started to expand. The creation is then explained by means of a sphere of light [35].
Grosseteste's work in optics was continued by Roger Bacon. There is also an interesting quotation often reported in the history of telescope. In his treatise entitled “De Iride”, Grosseteste writes that a part of optics, “when well understood, shows us how we may make things a very long distance off appear as if placed very close, and large near things appear very small, and how we may make small things placed at a distance appear any size we want, so that it may be possible for us to read the smallest letters at incredible distances, or to count sand, or seed, or any sort of minute objects.” It is probable that Grosseteste made some experiments using lenses and mirrors [36,37].
[32] N. Lewis, Robert Grosseteste, in The Stanford Encyclopedia of Philosophy, 2010, E.N. Zalta ed.
[33] H.G. Gauch, Jr., Scientific Method in Practice, Cambridge University Press, 2003, p.222.
[34] W. A. Wallace, Prelude to Galileo: Essays on Medieval and Sixteenth-Century Sources of Galileo's Thought, Springer, 1981.
[35] F. Adorno, T. Gregory and V. Verra, Storia della Filosofia, Bari: Laterza, 1973.
[36] A.C. Sparavigna, "Translation and discussion of the De Iride, a treatise on optics by Robert Grosseteste," arXiv, 2012, History and Philosophy of Physics, arxiv:1211.5961.
[37] A.C. Sparavigna, "Reflection and refraction in Robert Grosseteste's De Lineis, Angulis et Figuris," arXiv, 2013, History and Philosophy of Physics, arxiv:1302.1885.
I have translated and discussed some Grosseteste's treatises, you can find th links to download them freely at
http://physics-sparavigna.blogspot.it/2014/04/robert-grosseteste_8.html
9. Grosseteste and the Sphere of Light
Robert Grosseteste (1175-1253) was an English philosopher who became the Bishop of Lincoln. As a scientist he had a quite important role in the medieval school of Oxford [32]. In his works, in particular in the commentaries of Aristotle’s philosophy, Grosseteste devised a scientific method. From particular observations, we can find a universal law, and then, from these laws we can predict some peculiar cases. Grosseteste called this “resolution and composition” [33]. As a consequence, Grosseteste tells that physics needs the ‘experimentum’, that is, a proof from experience. These ideas were a prelude for the Galilean science in the 17th century [34]. The method of “resolution and composition” was applied to geometry and optics. Moreover, optics is described by geometry, because optics depends on geometry. As a conclusion, Grosseteste argued that mathematics was the highest science, basis for all others. Here we see that he understood the necessity to describe the physical phenomena in a mathematic formalism. Grosseteste believed that at the beginning of times, it wasthe light to move the universe. In his “De Luce”, Grosseteste explains the origin of the world. God created matter and light together in a point. Due to its nature the light propagated isotropically in all directions. It immediately became a sphere and, accordingly, dragged by the light, the matter started to expand. The creation is then explained by means of a sphere of light [35].
Grosseteste's work in optics was continued by Roger Bacon. There is also an interesting quotation often reported in the history of telescope. In his treatise entitled “De Iride”, Grosseteste writes that a part of optics, “when well understood, shows us how we may make things a very long distance off appear as if placed very close, and large near things appear very small, and how we may make small things placed at a distance appear any size we want, so that it may be possible for us to read the smallest letters at incredible distances, or to count sand, or seed, or any sort of minute objects.” It is probable that Grosseteste made some experiments using lenses and mirrors [36,37].
[32] N. Lewis, Robert Grosseteste, in The Stanford Encyclopedia of Philosophy, 2010, E.N. Zalta ed.
[33] H.G. Gauch, Jr., Scientific Method in Practice, Cambridge University Press, 2003, p.222.
[34] W. A. Wallace, Prelude to Galileo: Essays on Medieval and Sixteenth-Century Sources of Galileo's Thought, Springer, 1981.
[35] F. Adorno, T. Gregory and V. Verra, Storia della Filosofia, Bari: Laterza, 1973.
[36] A.C. Sparavigna, "Translation and discussion of the De Iride, a treatise on optics by Robert Grosseteste," arXiv, 2012, History and Philosophy of Physics, arxiv:1211.5961.
[37] A.C. Sparavigna, "Reflection and refraction in Robert Grosseteste's De Lineis, Angulis et Figuris," arXiv, 2013, History and Philosophy of Physics, arxiv:1302.1885.
I have translated and discussed some Grosseteste's treatises, you can find th links to download them freely at
http://physics-sparavigna.blogspot.it/2014/04/robert-grosseteste_8.html
Subscribe to:
Posts (Atom)