1,160 research outputs found
Alternative derivation of the relativistic contribution to perihelic precession
An alternative derivation of the first-order relativistic contribution to
perihelic precession is presented. Orbital motion in the Schwarzschild geometry
is considered in the Keplerian limit, and the orbit equation is derived for
approximately elliptical motion. The method of solution makes use of coordinate
transformations and the correspondence principle, rather than the standard
perturbative approach. The form of the resulting orbit equation is similar to
that derived from Newtonian mechanics and includes first-order corrections to
Kepler's orbits due to general relativity. The associated relativistic
contribution to perihelic precession agrees with established first-order
results. The reduced radius for the circular orbit is in agreement to
first-order with that calculated from the Schwarzschild effective potential.
The method of solution is understandable by undergraduate students.Comment: 12 pages, 2 figures. Accepted for publication in the American Journal
of Physic
Mean-payoff Automaton Expressions
Quantitative languages are an extension of boolean languages that assign to
each word a real number. Mean-payoff automata are finite automata with
numerical weights on transitions that assign to each infinite path the long-run
average of the transition weights. When the mode of branching of the automaton
is deterministic, nondeterministic, or alternating, the corresponding class of
quantitative languages is not robust as it is not closed under the pointwise
operations of max, min, sum, and numerical complement. Nondeterministic and
alternating mean-payoff automata are not decidable either, as the quantitative
generalization of the problems of universality and language inclusion is
undecidable.
We introduce a new class of quantitative languages, defined by mean-payoff
automaton expressions, which is robust and decidable: it is closed under the
four pointwise operations, and we show that all decision problems are decidable
for this class. Mean-payoff automaton expressions subsume deterministic
mean-payoff automata, and we show that they have expressive power incomparable
to nondeterministic and alternating mean-payoff automata. We also present for
the first time an algorithm to compute distance between two quantitative
languages, and in our case the quantitative languages are given as mean-payoff
automaton expressions
Fourth order indirect integration method for black hole perturbations: even modes
On the basis of a recently proposed strategy of finite element integration in
time domain for partial differential equations with a singular source term, we
present a fourth order algorithm for non-rotating black hole perturbations in
the Regge-Wheeler gauge. Herein, we address even perturbations induced by a
particle plunging in. The forward time value at the upper node of the
grid cell is obtained by an algebraic sum of i) the preceding node values of
the same cell, ii) analytic expressions, related to the jump conditions on the
wave function and its derivatives, iii) the values of the wave function at
adjacent cells. In this approach, the numerical integration does not deal with
the source and potential terms directly, for cells crossed by the particle
world line. This scheme has also been applied to circular and eccentric orbits
and it will be object of a forthcoming publication.Comment: This series of papers deals with EMRI for LISA. With the respect to
the v1 version, the algorithm has been improved; convergence tests and
references have been added; v2 is composed by 23 pages, and 6 figures. Paper
accepted by Class. Quantum Gravity for the special issue on Theory Meets Data
Analysis at Comparable and Extreme Mass Ratios (Capra and NRDA) at Perimeier
Institute in June 201
Insights in Health Administration Education: Understanding the Role of Personality in Teamwork
Background: Developing a health promotion program plan requires attention to the links between objectives, activities, and overall program goals. Instructors developed the “Connecting the Dots” worksheet to help students establish these linkages.
Methods: The “Connecting the Dots” worksheet included six questions pertinent to the students’ health promotion program plans. The worksheet was given to the students in a flipped classroom setting. Evaluation of the effectiveness of the tool was based upon group presentations at the end of the semester.
Results: Students developed more viable program plans that included stronger links between objectives and corresponding program activities.
Conclusions: The “Connecting the Dots” worksheet is a promising tool for engaging public health students in the process of developing health promotion program plans
Nonlocal Astroparticles in Einstein's Universe
Gravitational probes should maintain spatial flatness for
Einsten-Infeld-Hoffmann dynamics of relativistic matter-energy. The continuous
elementary source/particle in Einstein's gravitational theory is the r^{-4}
radial energy density rather than the delta-operator density in empty-space
gravitation. The space energy integral of such an infinite (astro)particle is
finite and determines its nonlocal gravitational charge for the
energy-to-energy attraction of other nonlocal (astro)particles. The non-empty
flat space of the undivided material Universe is charged continuously by the
world energy density of the global ensemble of overlapping radial particles.
Nonlocal gravitational/inertial energy-charges incorporate Machian relativism
quantitatively into Einstein's gravitation for self-contained SR-GR dynamics
without references on Newton's mass-to-mass attraction.Comment: 9 pages, typos and arguments adde
Complex Lithofacies Relationships between the Ste. Genevieve and Paoli Limestones: Clarifying Reservoir Relationships in the Indiana Subsurface
This poster was presented at the American Association of Petroleum Geologists (AAPG) Eastern Section Meeting in Evansville, Indiana,on September 22, 2009.Typically irregular vertical and lateral distribution of lithofacies within the Ste. Genevieve and Paoli
Limestones (Mississippian Blue River Group) has historically resulted in the inaccurate correlation
of uppermost Ste. Genevieve lithologies (Joppa Member) with Paoli units of similar composition and
appearance (Aux Vases and Renault Members). The Joppa Member of the Ste. Genevieve thins
northeastward toward the Illinois Basin margin, losing the distinctive log signature that characterizes
this unit in more basinward locations. The Aux Vases and Renault Members of the Paoli Limestone also
become difficult to distinguish from each other and from the Joppa Member in basin margin locations
because of rapid changes in composition and bed distribution. As a consequence, many Ste. Genevieve
and Paoli Limestone pay zones have been assigned to the wrong reservoir pool, sometimes within the
same field.
Pay zones from Ste. Genevieve and Paoli Limestone reservoirs were reassigned according to current
stratigraphic divisions. These new correlations more accurately reflect spatial relationships within and
between hydrocarbon pools, and could contribute to more effective reservoir management. Improved
correlations should also provide a useful tool for future hydrocarbon exploration and development
activities in Indiana. Our investigation also suggests that revisions to formal Ste. Genevieve-Paoli stratigraphic nomenclature should be considered
The role of the ecological fiscal transfers for water conservation policies
The purpose of this chapter is to fill the lacuna found in the literature with regard to describing the role of EFTs for water conservation policies. The literature tells us that ecological fiscal transfers (EFTs) are analysed so to pursue biodiversity conservation policies and solid waste management (SWM). For biodiversity conservation policies, EFTs have two purposes: (1) to incentivize municipalities to create local protected areas (PA); and (2) to compensate municipalities for corresponding land-use restrictions. In the case of SWM, the main idea is that, even considering the fees paid by the households, it is still costly to maintain waste services in the municipal territories. In this context, EFTs are appealing policy instrument to help local governments create landfills or composting plants. However, in Brazil EFTs are functioning as a policy instrument which also includes a wide range of policy domains, such as water conservation, indigenous land, fire-control, and so on. Six states adopted EFTs specifically for water conservation policies: Goiás, Paraná, Pernambuco, Piauí, Rio de Janeiro, and Tocantins. Descriptive analyses, focusing on legislative differences are conducted for each of these states.(undefined
A Classification of Countable Lower 1-transitive Linear Orders
This paper contains a classification of countable lower 1-transitive linear orders. This is the first step in the classification of countable 1-transitive trees given in Chicot and Truss (2009): the notion of lower 1-transitivity generalises that of 1-transitivity for linear orders, and it is essential for the structure theory of 1-transitive trees. The classification is given in terms of coding trees, which describe how a linear order is fabricated from simpler pieces using concatenations, lexicographic products and other kinds of construction. We define coding trees and show that a coding tree can be constructed from a lower 1-transitive linear order (X,≤) by examining all the invariant partitions on X. Then we show that a lower 1-transitive linear order can be recovered from a coding tree up to isomorphism
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