On the elements of the orbit of the comet of Halley in 1759

1837 ◽  
Vol 3 ◽  
pp. 332-332
Keyword(s):  
The Other ◽  
The Earth ◽  
Halley's Comet ◽  
Perihelion Passage

In calculating the elements of Halley’s comet, former astronomers have in general adopted the parabolic hypothesis, neglecting the reciprocal of the semi-axis major; and even in the more recent investigations of its orbit, no accurate value of this quantity has been employed. Mr. Lubbock, perceiving the serious effect which an error in the semi-axis major would occasion in the determination of the other elements, renewed these very laborious calculations, assuming as the value of this quantity that given by M. Pontécoulant, in his “Théorie analytique du Systême du Monde;” taking also into account the alterations which the elements of the comet have undergone by the action of the planets, and likewise the effect of precession upon the longitude of the node, and of the perihelion. The author takes this opportunity of correcting the very erroneous statements that have been made respecting the results of his investigations, especially with regard to the time of the perihelion passage, which is, of course, very different from that of its actual appearance to spectators on the earth; although these two epochs are frequently confounded with one another.

THE USE OF CUMULATIVE RESISTANCE IN EARTH-RESISTIVITY SURVEYS

1945 ◽  
Vol 23a (4) ◽  
pp. 57-72 ◽  
Author(s):  
R. Ruedy
Keyword(s):  
Apparent Resistivity ◽  
Middle Layer ◽  
The Other ◽  
Electrode Spacing ◽  
Line Graphs ◽  
Earth Resistivity ◽  
The Earth ◽  
Straight Line ◽  
The Individual

When the soil is assumed to consist of two layers—the upper of resistivity ρ1 and the lower of resistivity ρ2—and cumulative resistances are calculated by adding or integrating the earth-resistivity functions for intervals that are a fraction of the thickness of the upper layer, a practically linear relation is obtained between the cumulative resistance and the electrode spacing until the distance between the electrodes is equal to the thickness of the upper material. Should one of the materials be at least twice as conducting as the other, the extent of the deviation from the linear law enables the determination of the depth of the upper stratum and of the ratio between the resistivities of the two layers. When three layers are present and the middle layer is at least twice as thick as the top stratum, the thicknesses may be deduced from the two departures of the cumulative resistances from the linear law. Since these conclusions are based on the theory of the individual apparent resistivity of stratified ground at various electrode spacings, they have the same range of application as the earth-resistivity curves, but the occurrence of straight line graphs facilitates the plotting and the interpretation of results based on a necessarily limited number of measurements.

The past orbit of Halley’s comet

1974 ◽  
Vol 22 ◽  
pp. 171-173
Author(s):  
T. Kiang
Keyword(s):  
English Translation ◽  
The Other ◽  
Complete Coverage ◽  
The Past ◽  
Halley's Comet ◽  
Right Ascension ◽  
Perihelion Passage ◽  
Made In

I have re-examined the records in the Chinese“Standard Histories”on this famous object, including one set of relatively precise observations made in the year 837 A.D., which has only recently become available in an English translation (Ho 1962). This set, when properly interpreted, consists of the comet’s right ascension on 10 specified dates, given to the nearest half of a Chinese degree (1 Chinese degree = 360°/365.25). While the records of the other returns are not so precise, they can nevertheless be used with great advantage to determine the time of perihelion passage. These records provide an almost complete coverage back to the year 240 B.C.

scholarly journals Gubitak transcedencije i nastojanje oko sigurnosti unutar svijeta

2018 ◽  
Vol 25 (2) ◽  
Author(s):  
Dušan Travar
Keyword(s):  
World View ◽  
Modern Society ◽  
Human Existence ◽  
The Other ◽  
The Earth ◽  
The World ◽  
Cultural Processes ◽  
Specific Manner ◽  
The One

The "world view" influences the basic determination of man to the extent that all phenomena and events, all scientific problematizations and socio-cultural processes and, not least, human existence itself are networked into a coordinating system which is enmeshed in the "here present" or in the "otherworldly". Knowing one’s enmeshment in the otherworldly offers to man the possibility to experience in a specific manner the dangers and the risks of human existence and not to take the world as the only reality. Christianity demythologized the world and with the Biblical creative injunction addressed to man to subjugate the Earth it contributed to progress as a path of discovering and controlling the world. However, regardless of the nature of security within the world, progress is immanently prone to risk ("the remaining risk"). The loss of the otherworldly in modern society, on the one hand, contributes to the growing attenuation of endangerment of life but, on the other, man is becoming more and more insecure despite the enormous efforts devoted to security. This can ultimately lead to a point where "progress" is experienced as a power which endangers security and which needs to be curtailed.

XIX. On the mean density of the Earth

1821 ◽  
Vol 111 ◽  
pp. 276-292 ◽  
Keyword(s):  
Precise Determination ◽  
The Other ◽  
The Earth ◽  
The Mean ◽  
Whole Earth

Although the determination of the mean density of the whole terraqueous globe of our planet, is admitted to be a problem of the utmost importance to several branches of philosophy, particularly to physical astronomy, and the figure and constitution of the earth; it would seem, from the dis­cordancy of the declared opinions of some eminent philoso­phers, that the problem is still in an uncertain state. Since the first notice of this subject by Newton, in his admirable Principia, it has often been incidentally alluded to, without receiving a precise determination; with the exception of two instances only, in which it has been stated to be, certainly or approximately, determined by experiment; namely, in the case of the Schehallien experiment, by Dr. Maskelyne and myself, and by the Honorable Henry Cavendish, by a method invented by Mr. Michell. The former of these experiments was made by Dr. Maskelyne, in the years 1774, 1775, and 1776, by means of that large mountain in Scotland, in measuring its dimensions, and in comparing its attraction on a plummet, with that of the whole earth on the same; the calculations on it having been made by myself, and first published in the Philoso­phical Transactions of the year 1778; and since more correctly in the second volume of my Mathematical Tracts. The other experiment, by Mr. Cavendish, was by observing the attraction on small pendulous balls, of two inches di­ameter, by larger ones of ten inches diameter, as compared with the attraction of the earth on the same.

MAGNETOSPHERIC TRANSMISSION FUNCTION TO SEPARATE NEAR EARTH PRIMARY AND SECONDARY COSMIC RAYS

2005 ◽  
Vol 20 (29) ◽  
pp. 6678-6680 ◽  
Author(s):  
P. BOBIK ◽  
M. BOSCHINI ◽  
M. GERVASI ◽  
D. GRANDI ◽  
E. MICELOTTA ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Field Model ◽  
Primary Particle ◽  
Charged Particles ◽  
Transmission Function ◽  
The Other ◽  
Solar Cycles ◽  
The Earth ◽  
The Moment

The main features of charged particles accessing the Earth magnetosphere have been studied by tracing their trajectories. The reconstruction code has allowed us to perform two simulations of Cosmic Rays (CRs) accessing the AMS detector, one for the 1998 data, and the other for the 2005 (at the moment, the IGRF data are available up to that year). The parameters of the external field model for 2005 have been estimated from the solar conditions in 1982 and 1984, two solar cycles before. The CRs have been assumed to be isotropically impinging on the AMS detector, flying at 400 km altitude with energies reproducing the AMS-01 observed spectrum. The computation of allowed and forbidden primary particle trajectories has enabled us the estimate of the Transmission Function in both periods. A comparison with the overall (primary and secondary) AMS-01 data provides by subtraction the determination of the secondary spectrum.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

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