12,522 research outputs found
Measuring the Rotation Speed of Giant Stars From Gravitational Microlensing
During some gravitational lensing events, the lens transits the face of the
star. This causes a shift in the apparent radial velocity of the star which is
proportional to its rotation speed. It also changes the magnification relative
to what would be expected for a point source. By measuring both effects, one
can determine the rotation parameter . The method is especially useful
for K giant stars because these have turbulent velocities that are typically
large compared with their rotation speed. By making a series of radial velocity
measurements, one can typically determine to the same accuracy as the
individual radial velocity measurements. There are approximately 10
microlensing transit events per year which would be suitable to make these
measurements.Comment: 11 pages including 1 embedded figur
Social Democratic Reform Proposals and the Future of Capitalism
This paper seeks to present an analysis of some issues raised in the debate on the future of capitalism by influential social democrats in recent years [Agleitta (1999); Habermas (1999); Rorty (1998)]. We begin with a brief description of capitalism's genesis, its characteristics and its need for moral legitimising and proceed to a slightly more extended discussion of capitalist processes at the beginning of the twenty-first century. The paper concludes with an assessment of initiatives proposed by social democratic thinkers such as Agleitta, Habermas and Rorty to strengthen capitalism and realise social democratic objectives—the universalisation of freedom and the promotion of liberal justices in rights centric societies.
Solution of Linear Programming Problems using a Neural Network with Non-Linear Feedback
This paper presents a recurrent neural circuit for solving linear programming problems. The objective is to minimize a linear cost function subject to linear constraints. The proposed circuit employs non-linear feedback, in the form of unipolar comparators, to introduce transcendental terms in the energy function ensuring fast convergence to the solution. The proof of validity of the energy function is also provided. The hardware complexity of the proposed circuit compares favorably with other proposed circuits for the same task. PSPICE simulation results are presented for a chosen optimization problem and are found to agree with the algebraic solution. Hardware test results for a 2–variable problem further serve to strengthen the proposed theory
Technological Capability Building in South Korea: Some Lessons for Pakistan
Recent economic upheavals raise important questions about the nature of the transformation that has taken place in the East Asian economics. Are these economics really catching up with the West? Is there growth process sustainable? Or will they suffer the type of systemic disintegration experienced by the East European countries during the 1990s—Paul Krugman (1994) and Young (1994) had demonstrated similarities in the East Asian and East European growth paths some time ago. Technological upgrading is an important element in the development of a sustainable growth strategy. This paper seeks to describe policies and initiatives taken by the South Korean government to stimulate technological learning during 1960–1990—the decades during which the South Korean economy achieved a “miraculous” transformation. The description relics mainly on Korean sources and is based on our own field research in that country. Section one describes the technological learning processes and Section Two presents a discussion of the policies that facilitated this learning. Section Three briefly addresses the question: Did this type of technological learning make a contribution towards enhancing the sustainability of Korean development processes? The concluding section briefly reflects on the lessons that seem relevant for Pakistan.
A Search for an Optimum Currency Area Partners for Pakistan
This paper empirically examines the existence of a common trend between the exchange rates of Pakistan and four regional countries (Bangladesh, India, Saudi Arabia, and Sri Lanka) with two of their major trading partners (the United States and Japan) as base countries. Results from cointegrating analysis show that the strongest evidence points to the existence of common stochastic trends between the Pakistani rupee, on the one hand, and the Bangladeshi Taka and the Sri Lankan rupee, on the other hand. There is no strong evidence for the existence of a common stochastic trend between the Pakistani rupee and the currencies of India and Saudi Arabia. Optimum Currency Area (OCA) theory seems to justify the formation of a currency union between Pakistan, Bangladesh, and Sri Lanka. The case of a currency union between Bangladesh and Pakistan is strengthened by a shared political past and a shared history of financial institutional development. The immediate impact of the formation of such union on Pakistan’s GDP growth will however be insignificant.Currency, pakistan
The effect of formulation and processing variables on granule microstructure
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A New Channel for the Detection of Planetary Systems Through Microlensing: II. Repeating Events
In the companion paper we began the task of systematically studying the
detection of planets in wide orbits () via microlensing surveys.
In this paper we continue, focusing on repeating events. We find that, if all
planetary systems are similar to our own Solar System, reasonable extensions of
the present observing strategies would allow us to detect 3-6 repeating events
per year along the direction to the Bulge. Indeed, if planetary systems with
multiple planets are common, then future monitoring programs which lead to the
discovery of thousands of stellar-lens events will likely discover events in
which several different planets within a single system serve as lenses, with
light curves exhibiting multiple repetitions. In this paper we discuss
observing strategies to maximize the discovery of all wide-orbit planet-lens
events. We also compare the likely detection rates of planets in wide orbits to
those of planets located in the zone for resonant lensing. We find that,
depending on the values of the planet masses and stellar radii of the lensed
sources (which determine whether or not finite source size is important), and
also on the sensitivity of the photometry used by observers, the detection of
planets in wide orbits may be the primary route to the discovery of planets via
microlensing. We also discuss how the combination of resonant and wide-orbit
events can help us to learn about the distribution of planetary system
properties (S 6.1). In addition, by determining the fraction of short-duration
events due to planets, we indirectly derive information about the fraction of
all short-duration events that may be due to low-mass MACHOs (S 6.2).Comment: 51 pages, 7 figures. To be published in the Astrophysical Journal, 20
February 1999. This completes the introduction to the discovery of planets in
wide orbits begun in astro-ph/9808075, also to appear in ApJ on 20 February
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The Rapid and Sensitive Quantitative Determination of Galactose by Combined Enzymatic and Colorimetric Method: Application in Neonatal Screening
The quantitative measurement of galactose in blood is essential for the early diagnosis, treatment, and dietary monitoring of galactosemia patients. In this communication, we aimed to develop a rapid, sensitive, and cost-effective combined method for galactose determination in dry blood spots. This procedure was based on the combination of enzymatic reactions of galactose dehydrogenase (GalDH), dihydrolipoyl dehydrogenase (DLD), and alkaline phosphates with a colorimetric system. The incubation time and the concentration of enzymes used in new method were also optimized. The analytical performance was studied by the precision, recovery, linearity, and sensitivity parameters. Statistical analysis was applied to method comparison experiment. The regression equation and correlation coefficient (R2) were Y = 0.0085x + 0.032 and R2 = 0.998, respectively. This assay exhibited a recovery in the range of 91.7–114.3 % and had the limit detection of 0.5 mg/dl for galactose. The between-run coefficient of variation (CV) was between 2.6 and 11.1 . The within-run CV was between 4.9 and 9.2 . Our results indicated that the new and reference methods were in agreement because no significant biases exist between them. Briefly, a quick and reliable combined enzymatic and colorimetric assay was presented for application in newborn mass screening and monitoring of galactosemia patients. © 2016 Springer Science+Business Media New Yor
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