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1.
A flexible configuration for an array of sensors has been developed for measurements in energetic regions of the ocean where the flow has high spatial and temporal variability. Central to the system is a two-axis electromagnetic current meter that measures the flow through a ducted volume containing a uniform magnetic field and nonprotruding electrodes flush with the duct surfaces. This geometry minimizes the electrode boundary-layer effect on the output, thus improving calibration and reducing fouling and damage potential. An inexpensive amplifier designed for low signal-to-noise ratios is employed to produce very low zero drift during operation 相似文献
2.
Wilfred H. Sorrell 《Astrophysics and Space Science》2009,323(2):205-211
Almost all astronomers now believe that the Hubble recession law was directly inferred from astronomical observations. It
turns out that this common belief is completely false. Those models advocating the idea of an expanding universe are ill-founded
on observational grounds. This means that the Hubble recession law is really a working hypothesis. One alternative to the
Hubble recession law is the tired-light hypothesis originally proposed by Zwicky (Proc. Nat. Acad. Sci. 15:773, 1929). This hypothesis leads to a universe that is an eternal cosmos continually evolving without beginning or end. Such a universe
exists in a dynamical state of virial equilibrium. Observational studies of the redshift-magnitude relation for Type Ia supernovae
in distant galaxies might provide the best observational test for a tired-light cosmology. The present study shows that the
model Hubble diagram for a tired-light cosmology gives good agreement with the supernovae data for redshifts in the range
0<z<2. This observational test of a static cosmology shows that the real universe is not necessarily undergoing expansion nor
acceleration.
An erratum to this article can be found at 相似文献
3.
Wilfred H. Sorrell 《Astrophysics and Space Science》2008,317(1-2):59-70
During the nineteenth century, it was common for physicists to believe in the existence of a material vacuum composed of an incompressible fluid that fills the whole universe. This fluid was called the aether. Its original purpose was to provide an elastic tenuous medium for light propagation through space. Although it is well understood today that no such medium is needed for light propagation, the existence of a cosmic aether medium in space is still possible and its physical properties can be understood on models of cosmology that have nothing to do with Big-Bang cosmology. It is possible that electromagnetic radiation emitted by the cosmic aether medium has already been detected. The low-frequency electromagnetic radiation emitted by the aether is called the cosmic microwave background radiation. The present study outlines a model for an aether medium that explains the genesis of the microwave background radiation in a closed static (nonexpanding) universe. It is shown that the spectrum of the microwave background radiation is a perfect blackbody with a temperature T rad=2.77 K in harmony with the perfect cosmological principle. It is further shown that the aether medium is opaque at radio and microwave frequencies. This particular feature of the model does not contradict any observations regarding the existence of distant radio galaxies and quasars. 相似文献
4.
Wilfred H. Sorrell 《Astrophysics and Space Science》1982,85(1-2):3-15
In this paper the magnetic superstar model is used to discuss QSO luminosity and density evolution. Our main hypotheses are that (i) mass loss from old stars in massive galaxies cools and then falls into the centre to form a nuclear disc (Bailey, 1980); and (ii) magnetic superstars in galactic nuclei condense out of gaseous material at the centre of a supermassive-magnetised disc (Kundt, 1979). On this generalised model we find that the non-thermal (synchrotron) optical luminosity scales asL
opt L
3
t
–7/3, whereL is the total blue luminosity of old stars in the galaxy and t is cosmic time. In addition we show that QSO co-moving density follows the lawD(t)exp-(t/t
Evol)16/15 with an evolution timescalet
Evol = 1.95 × 109 yr. The model as a whole is in good agreement with observations. 相似文献
5.
6.
A growing number of commentators are forecasting a near-term peak and subsequent terminal decline in the global production
of conventional oil as a result of the physical depletion of the resource. These forecasts frequently rely on the estimates
of the ultimately recoverable resources (URR) of different regions, obtained through the use of curve-fitting to historical trends in discovery or production. Curve-fitting was originally pioneered by M. King Hubbert in the context
of an earlier debate about the future of the US oil production. However, despite their widespread use, curve-fitting techniques
remain the subject of considerable controversy. This article classifies and explains these techniques and identifies both
their relative suitability in different circumstances and the level of confidence that may be placed in their results. This
article discusses the interpretation and importance of the URR estimates, indicates the relationship between curve fitting
and other methods of estimating the URR and classifies the techniques into three groups. It then investigates each group in
turn, indicating their historical origins, contemporary application and major strengths and weaknesses. The article then uses
illustrative data from a number of oil-producing regions to assess whether these techniques produce consistent results as
well as highlight some of the statistical issues raised and suggesting how they may be addressed. The article concludes that
the applicability of curve-fitting techniques is more limited than adherents claim and that the confidence bounds on the results
are wider than usually assumed. 相似文献
7.
We reviewed lakes in New Zealand reported to have undergone regime shifts between macrophyte‐dominated clear water states and de‐vegetated, turbid states. Regime‐shifting lakes (RSLs) occurred along a wide latitudinal gradient. We obtained catchment land‐use data as well as data on the occurrences of introduced (non‐indigenous) macrophytes and herbivorous and benthivorous fish for the 37 RSLs and for 58 lakes with similar maximum depths and climates, but which had not been reported to have undergone regime shifts. All RSLs had a maximum depth <20 m and mean annual surface air temperature between 9 and 16°G Regime shifts were positively related to the percentage of the catchment in pasture and negatively related to the percentage of the catchment in forest. The occurrences of the introduced macrophyte Egeria densa and the introduced fish, Ameiurus nebulosus (catfish), Carassius auratus (goldfish), Scardinius erythrophthalmus (rudd), Cyprinus carpio (koi carp), and Tinca tinca (tench), were significantly correlated to regime shifts in lakes. Although the presence of other introduced aquatic macrophytes was not significantly correlated with RSLs, the number of exotic fish taxa present in lakes was strongly positively correlated with increasing prevalence of regime shifts. The strength of the correlations between land use and introduced species versus regime shifts illustrates a number of factors which could be managed to reduce the susceptibility of lakes to regime shifts and to restore lakes that have become de‐vegetated. Our findings also suggests that regime shifts in lakes were unlikely to have been common in New Zealand lakes before anthropogenic deforestation and introductions of introduced aquatic taxa. 相似文献
8.
Wilfred H. Sorrell 《Astrophysics and Space Science》1997,253(1):27-41
Some two decades ago, Hoyle and Wickramasinghe (1976) proposed that the physical conditions inside dense molecular clouds
favour the formation of amino acids and complex organic polymers. There now exists both astronomical and laboratory evidence
supporting this idea. Recent millimeter array observations have discovered the amino acid glycine (NH2CH2COOH) in the gas phase of the dense star-forming cloud Sagittarius B2. These observations would pose serious problems for
present-day theories of molecule formation in space because it is unlikely that glycline can form by the gas-phase reaction
schemes normally considered for dense cloud chemistry. Several laboratory experiments suggest a new paradigm in which amino
acids and other large organic molecules are chemically manufactured inside the bulk interior of icy grain mantles photoprocessed
by direct and scattered ultraviolet starlight. Frequent chemical explosions of the processed mantles would eject large fragments
of organic dust into the ambient cloud. Large dust fragments break up into smaller ones by sputtering and ultimately by photodissociation
of individual molecules. Hence, a sizeable column density (N≈ 1010−1015 cm-2) of amino acids would be present in the gaseous medium as a consequence of balancing the rate of supply from exploding mantles
with the rate of molecule destruction. Exploding mantles can therefore solve the longstanding molecule desorption problem
for interstellar dense cloud chemistry. A sizeable fraction of the organic dust population can survive destruction and seed
primitive planetary systems throughout our galaxy with prebiological organic molecules needed for proteins and nucleic acids
in living organisms. This possibility provides fresh grounds for a new version of the old panspermia hypothesis first introduced
by Anaxagoras. It is shown that panspermia is more important than asteroid and cometary organic depositions onto primitive
Earth. Furthermore, no appeal to Miller-Urey synthesis in a nonoxidizing atmosphere of primitive Earth is then needed to seed
terrestrial life.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
10.
Wilfred H. Sorrell 《Astrophysics and Space Science》2008,317(1-2):45-58
The present paper outlines a cosmological paradigm based upon Dirac’s large number hypothesis and continual creation of matter in a closed static (nonexpanding) universe. The cosmological redshift is caused by the tired-light phenomenon originally proposed by Zwicky. It is shown that the tired-light cosmology together with continual matter creation has a universal Hubble constant H 0=(512π 2/3)1/6(GC 0)1/3 fixed by the universal rate C 0 of matter creation, where G is Newton’s gravitational constant. It is also shown that a closed static universe has a finite age τ 0=(243π 5/8GC 0)1/3 also fixed by the universal rate of matter creation. The invariant relationship H 0 τ 0=3π 261/2 shows that a closed static universe is much older (≈one trillion years) than any expanding universe model based upon Big-Bang cosmology. It is this property of a static universe that resolves any cosmic age crisis provided that galaxy formation in the universe is a continual recurring process. Application of Dirac’s large number hypothesis gives a matter creation rate C 0=4.6×10?48 gm?cm?3?s?1 depending only on the fundamental constants of nature. Hence, the model shows that a closed static universe has a Hubble constant H 0=70 km?s?1?Mpc?1 in good agreement with recent astronomical determinations of H 0. By using the above numerical value for H 0 together with observational data for elongated cellular-wall structures containing superclusters of galaxies, it is shown that the elongated cellular-wall configurations observed in the real universe are at least one hundred billion years old. Application of the microscopic laws of physics to the large-scale macroscopic universe leads to a static eternal cosmos endowed with a matter-antimatter symmetry. It is proposed that the matter-antimatter asymmetry is continuously created by particle-antiparticle pair annihilation occurring in episodic cosmological gamma-ray bursts observed in the real universe. 相似文献