Solar observations in ancient China and solar variability

1990 ◽  
Vol 330 (1615) ◽  
pp. 513-515 ◽  
Keyword(s):  
Solar Activity ◽  
Power Spectrum ◽  
Solar Variability ◽  
Ancient China ◽  
Naked Eye ◽  
The Third ◽  
Solar Observations ◽  
History Of ◽  
Long Term Variations

In this paper I review both the history of solar observations in ancient China and recent researches on solar variability. The paper consists of three parts. In the first part I describe Sun worship and the early observations of solar phenomena. In the second part I concentrate on sunspot observations and improving the catalogue of naked-eye sunspot records. In the third part I discuss long-term variations of solar activity by using historical sunspot records over 2000 years. The 210-year cycle, which has the largest significance in the power spectrum, may have an important influence on the forecasting of the next cycle (no. 22).

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.

The Exponential Nature of Technology

2017 ◽  
Author(s):  
Arlindo Oliveira
Keyword(s):  
Industrial Revolution ◽  
Technological Development ◽  
Exponential Functions ◽  
The Third ◽  
Agricultural Revolution ◽  
Nature Of Technology ◽  
History Of ◽  
Third Industrial Revolution ◽  
Industrial Revolutions

This chapter provides a brief review of the history of technology, covering pre-historical technologies, the agricultural revolution, the first two industrial revolutions, and the third industrial revolution, based on information technology. Evidence is provided that technological development tends to follow an exponential curve, leading to technologies that typically were unpredictable just a few years before. An analysis of a number of exponential trends and behaviors is provided, in order to acquaint the reader with the sometimes surprising properties of exponential growth. In general, exponential functions tend to grow slower than expected in the short term, and faster than expected in the long term. It is this property that make technology evolution very hard to predict.

Wanted: A Comparative History of the Modern Mediterranean

2012 ◽  
Vol 46 (1) ◽  
pp. 47-53
Author(s):  
Edmund Burke
Keyword(s):  
Sixteenth Century ◽  
Third World ◽  
Dominant Role ◽  
The West ◽  
The Third ◽  
History Of ◽  
The Mediterranean ◽  
The Third World

There is something seriously flawed about models of social change that posit the dominant role of in-built civilizational motors. While “the rise of the West” makes great ideology, it is poor history. Like Jared Diamond, I believe that we need to situate the fate of nations in a long-term ecohistorical context. Unlike Diamond, I believe that the ways (and the sequences) in which things happened mattered deeply to what came next. The Mediterranean is a particularly useful case in this light. No longer a center of progress after the sixteenth century, the decline of the Mediterranean is usually ascribed to its inherent cultural deficiencies. While the specific cultural infirmity varies with the historian (amoral familism, patron/clientalism, and religion are some of the favorites) its civilizationalist presuppositions are clear. In this respect the search for “what went wrong” typifies national histories across the region and prefigures the fate of the Third World.

scholarly journals Solar Modulation Effects in Terrestrial Production of Carbon-14

Radiocarbon ◽  
1980 ◽  
Vol 22 (2) ◽  
pp. 133-158 ◽  
Author(s):  
Giuliana Castagnoli ◽  
Devendra Lal
Keyword(s):  
Solar Activity ◽  
Cosmic Ray ◽  
Solar Modulation ◽  
Carbon 14 ◽  
Cosmic Ray Modulation ◽  
The Earth ◽  
Secular Variations ◽  
Galactic Cosmic Ray ◽  
Long Term Variations

This paper is concerned with the expected deviations in the production rate of natural 14C on the earth due to changes in solar activity. We review the published estimates of the global production rates of 14C due to galactic and solar cosmic ray particles, and present new estimates of the expected secular variations in 14C production, taking into account the latest information available on galactic cosmic ray modulation and long-term variations in solar activity.

History of myringotomy and grommets

2007 ◽  
Vol 121 (10) ◽  
pp. 911-916 ◽  
Author(s):  
J Rimmer ◽  
C E B Giddings ◽  
N Weir
Keyword(s):  
Current Practice ◽  
Gold Foil ◽  
Ventilation Tube ◽  
Inappropriate Use ◽  
The Third ◽  
Underlying Principle ◽  
Vinyl Tube ◽  
Cast Doubt ◽  
History Of

The first recorded myringotomy was in 1649. Astley Cooper presented two papers to the Royal Society in 1801, based on his observation that myringotomy could improve hearing. Widespread inappropriate use of the procedure followed, with no benefit to patients; this led to it falling from favour for many decades. Hermann Schwartze reintroduced myringotomy later in the nineteenth century. It had been realised earlier that the tympanic membrane heals spontaneously, and much experimentation took place in attempting to keep the perforation open. The first described grommet was made of gold foil. Other materials were tried, including Politzer's attempts with rubber. Armstrong's vinyl tube effectively reintroduced grommets into current practice last century. There have been many eponymous variants, but the underlying principle of creating a perforation and maintaining it with a ventilation tube has remained unchanged. Recent studies have cast doubt over the long-term benefits of grommet insertion; is this the end of the third era?

scholarly journals KILKA UWAG NA TEMAT ROLI III STATUTU LITEWSKIEGO W WYKŁADZIE PRAWA KRAJOWEGO NA PRZEŁOMIE XVIII I XIX WIEKU

2016 ◽  
Vol 10 (2) ◽  
pp. 129
Author(s):  
Sławomir Godek
Keyword(s):  
High School ◽  
Scientific Literature ◽  
The Third ◽  
Late Eighteenth ◽  
History Of ◽  
Lecture Courses ◽  
The Republic ◽  
The University

Some Remarks on the Role of the Third Statute of Lithuania in Courses on National Law at the Turn of the Nineteenth CenturySummary The long-term validity of the Third Lithuanian Statute of 1588 is a factor often highlighted in the scientific literature devoted to the history of the Lithuanian-Russian lands. The two and a half centuries that the codex operated have left a lasting imprint on the legal relations of these vast territories. In Belarusian lands once belonging the Republic and separated from it by the First Partition, the Statute was abolished as a consequence of the repression after the November Uprising in 1831. In the western and south-western guberniyas, the Statute survived somewhat longer; it was repealed in 1840. In academic circles, both Polish and international, the post-Partition fate of the Lithuanian codex has not yet been clarified. It seems that one aspect which is worth paying attention to in studies on the condition of the Statute after the Partitions is its role in the teaching of law in the late eighteenth and early nineteenth centuries. Surviving sources, in form of the lecture courses, students’ notes, reports intended for educational authorities and examination tables leave no doubt that the Statute of Lithuania was the very basis of national law lecture courses, both at the University of Vilnius, as well as at the High School and then Lyceum in Kremenets and the Academy of Polotsk. In the lectures of Adam Powstański, Ignacy Danilowicz, Aleksander Korowicki, Józef Jaroszewicz, Ignacy Ołdakowski, and Aleksander Mickiewicz, the Statute was always depicted as one of the most important sources of national law, which maintained its currency, and whose provisions were cited most frequently to illustrate the legal institutions under discussion.

scholarly journals Deep time diversity and the early radiations of birds

2021 ◽  
Vol 118 (10) ◽  
pp. e2019865118
Author(s):  
Yilun Yu ◽  
Chi Zhang ◽  
Xing Xu
Keyword(s):  
Evolutionary History ◽  
Large Scale ◽  
Evolutionary Rate ◽  
Rapid Evolution ◽  
Morphological Data ◽  
Deep Time ◽  
The Third ◽  
Time Diversity ◽  
History Of

Reconstructing the history of biodiversity has been hindered by often-separate analyses of stem and crown groups of the clades in question that are not easily understood within the same unified evolutionary framework. Here, we investigate the evolutionary history of birds by analyzing three supertrees that combine published phylogenies of both stem and crown birds. Our analyses reveal three distinct large-scale increases in the diversification rate across bird evolutionary history. The first increase, which began between 160 and 170 Ma and reached its peak between 130 and 135 Ma, corresponds to an accelerated morphological evolutionary rate associated with the locomotory systems among early stem birds. This radiation resulted in morphospace occupation that is larger and different from their close dinosaurian relatives, demonstrating the occurrence of a radiation among early stem birds. The second increase, which started ∼90 Ma and reached its peak between 65 and 55 Ma, is associated with rapid evolution of the cranial skeleton among early crown birds, driven differently from the first radiation. The third increase, which occurred after ∼40 to 45 Ma, has yet to be supported by quantitative morphological data but gains some support from the fossil record. Our analyses indicate that the bird biodiversity evolution was influenced mainly by long-term climatic changes and also by major paleobiological events such as the Cretaceous–Paleogene (K–Pg) extinction.

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