201,214 research outputs found
Deterrence of Corporate Fraud Through Securities Litigation: The Role of Institutional Investors
Johnson suggests that institutions are uniquely positioned to enhance the deterrence function of securities litigation without undermining the compensation goal
Reciprocating magnetic refrigerator employing tandem porous matrices within a reciprocating displacer
Disclosed is a method and apparatus for a magnetic refrigeration system. A continuously reciprocating displacer houses at least a pair of paramagnetic substances each of which is alternately driven into and out of a magnetic field. Two separate bidirectional pumping systems flow helium gas through the displacer and through both paramagnetic substances to create heat exchange conditions at two separate temperature extremes
The chemical signature of surviving Population III stars in the Milky Way
Cosmological simulations of Population (Pop) III star formation suggest that
the primordial initial mass function may have extended to sub-solar masses. If
Pop III stars with masses < 0.8 M_Sun did form, then they should still be
present in the Galaxy today as either main sequence or red giant stars. Despite
broad searches, however, no primordial stars have yet been identified. It has
long been recognized that the initial metal-free nature of primordial stars
could be masked due to accretion of metal-enriched material from the
interstellar medium (ISM). Here we point out that while gas accretion from the
ISM may readily occur, the accretion of dust from the ISM can be prevented due
to the pressure of the radiation emitted from low-mass stars. This implies a
possible unique chemical signature for stars polluted only via accretion,
namely an enhancement in gas phase elements relative to those in the dust
phase. Using Pop III stellar models, we outline the conditions in which this
signature could be exhibited, and we derive the expected signature for the case
of accretion from the local ISM. Intriguingly, due to the large fraction of
iron depleted into dust relative to that of carbon and other elements, this
signature is similar to that observed in many of the so-called carbon-enhanced
metal-poor (CEMP) stars. We therefore suggest that some fraction of the
observed CEMP stars may, in fact, be accretion-polluted Pop III stars.Comment: 9 pages, 9 figures, 1 table; accepted for publication in MNRA
Performance analysis of electrical circuits /PANE/
Automated statistical and worst case computer program has been designed to perform dc and ac steady circuit analyses. The program determines the worst case circuit performance by solving circuit equations
The diophantine problem Y² - X³ = A in a polynomial ring
Let C[z] be the ring of polynomials in z with complex coefficients; we consider the equation Y² — X³ = A, with A[is an element of]C[z] given, and seek solutions of this with X, Y[is an element of]C[z] i.e. we treat the equation as a "polynomial diophantine" problem. We show that when A is of degree 5 or 6 and has no multiple roots, then there are exactly 240 solutions (X, Y) to the problem with deg X ≤ 2 and deg Y ≤ 3
Molding process for imidazopyrrolone polymers
A process is described for producing shaped articles of imidazopyrrolone polymers comprising molding imidazopyrrolone polymer molding power under pressure and at a temperature greater than 475 C. Moderate pressures may be employed. Preferably, prior to molding, a preform is prepared by isostatic compression. The preform may be molded at a relatively low initial pressure and temperature; as the temperature is increased to a value greater than 475 C., the pressure is also increased
Subatmospheric Brayton-cycle Engine Program Review
A solar energy powered electrical generator utilizing a Subatmospheric Brayton cycle engine is examined. The generator consists of a subatmospheric, Brayton-cycle engine and a permanent magnet (PM) alternator. The electrical power is generated by an alternator driven directly by the Brayton-cycle engine rotating group. Features that enhance reliability and performance include air foil bearings on both the Brayton-cycle engine rotating group and the PM alternator, an atmospheric-pressure solar receiver and gas-fired trim heater, and a high temperature recuperator. The subatmospheric Brayton-cycle engine design is based on that of the gas fired heat pump engine
Book Review: Grit: The Power of Passion and Perseverance
I first stumbled across the research of Angela Duckworth after she was awarded the prestigious MacArthur Fellowship in 2013 for her work investigating the character traits that impact the achievement of long-term goals. So, when it was announced that she would be publishing a book in 2016, I immediately pre-ordered copy so that I could dig into her insights as soon as possible. When I received my copy of Grit: The Power of Passion and Perseverance in the mail, I was excited to crack it open… and then the self-doubt settled in. “What if, after reading the brilliant ideas of a scholar whom I highly regard, I realize that I have no grit… What if I don’t have what it takes?” I was terrified. But, I am convinced that I am not alone. In our current educational culture, one that reinforces a transactional ideology that success is unequivocally defined by test scores and GPA, what is one to do if they literally do not “measure up” to the competition? Is that the end of the road? Is success forever out of reach
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