3,163 research outputs found
Quality Counts 2012
In an attempt to gauge the educational progress of the nation and each state, Education Week has published state report cards since 1997 in its annual Quality Counts series. The 16th annual report - Quality Counts 2012 - was released in January. Overall, Arkansas ranked 5th among the 50 states and was one of only nine states in the U.S. that received a B. This policy brief examines Arkansas’ rank in each category of the report as well as the quality of the report itself
Active rc networks of low sensitivity for integrated circuit transfer function
Active RC network is capable of extremely high Q performance with exceptional stability and has independently adjustable zeros and poles. The circuit consists of two integrators and two summers that are interconnected to produce a complete second-order numerator and a second-order denominator
The differential diagnosis of some of the more important cystic diseases of the bones
Thesis (M.D.)--Boston Universit
Polymorphic systems with arrays : decidability and undecidability
Polymorphic systems with arrays (PSAs) is a general class of nondeterministic reactive systems. A PSA is polymorphic in the sense that it depends on a signature, which consists of a number of type variables, and a number of symbols whose types can be built from the type variables. Some of the state variables of a PSA can be arrays, which are functions from one type to another. We present several new decidability and undecidability results for parameterised control-state reachability problems on subclasses of PSAs
On model checking data-independent systems with arrays without reset
A system is data-independent with respect to a data type X iff the operations
it can perform on values of type X are restricted to just equality testing. The
system may also store, input and output values of type X. We study model
checking of systems which are data-independent with respect to two distinct
type variables X and Y, and may in addition use arrays with indices from X and
values from Y . Our main interest is the following parameterised model-checking
problem: whether a given program satisfies a given temporal-logic formula for
all non-empty nite instances of X and Y . Initially, we consider instead the
abstraction where X and Y are infinite and where partial functions with finite
domains are used to model arrays. Using a translation to data-independent
systems without arrays, we show that the u-calculus model-checking problem is
decidable for these systems. From this result, we can deduce properties of all
systems with finite instances of X and Y . We show that there is a procedure
for the above parameterised model-checking problem of the universal fragment of
the u-calculus, such that it always terminates but may give false negatives. We
also deduce that the parameterised model-checking problem of the universal
disjunction-free fragment of the u-calculus is decidable. Practical motivations
for model checking data-independent systems with arrays include verification of
memory and cache systems, where X is the type of memory addresses, and Y the
type of storable values. As an example we verify a fault-tolerant memory
interface over a set of unreliable memories.Comment: Appeared in Theory and Practice of Logic Programming, vol. 4, no.
5&6, 200
Helical Virus Structure: The Case of the Rhabdovirus Bullet
Commentary on Ge, P.; Tsao, J.; Schein, S.; Green, T.J.; Luo, M.; Zhou, Z.H. Cryo-EM model of the bullet-shaped vesicular stomatitis virus. Science 2010, 327, 689–693
Mini-Conference on Hamiltonian and Lagrangian Methods in Fluid and Plasma Physics
A mini-conference on Hamiltonian and Lagrangian methods in fluid and plasma
physics was held on November 14, 2002, as part of the 44th meeting of the
Division of Plasma Physics of the American Physical Society. This paper
summarizes the material presented during the talks scheduled during the
Mini-Conference, which was held to honor Allan Kaufman on the occasion of his
75th birthday.Comment: 14 pages, conference summar
The effect of sting interference at low speeds on the drag coefficient of an ellipsoidal body using a magnetic suspension and balance system
A Boltz body of revolution (fineness ratio 7.5:1) was tested in the Southampton University Magnetic Suspension and Balance System. The effects of sting interference on the drag coefficient of the model at zero angle of attack were noted as well as the effects on drag coefficient values at boundary layer trips. The drag coefficient values were compared with other sources and seemed to show agreement. The pressure distribution over the rear of the model with no sting interference was investigated including the use of boundary layer trips
NCLB Waivers
No Child Left Behind, or the Elementary and Secondary Education Act, is long overdue for reauthorization. Speculation concerning when and how this controversial act would be reauthorized has occurred throughout the Obama administration. In a somewhat surprising move last week, President Obama unilaterally created rules for NCLB waivers. This policy brief provides a brief background, followed by a discussion on the new NCLB flexibility and how these changes could affect schools in Arkansas
Raising the Kindergarten Entry Age
In recent years, the standards in Arkansas for entry into kindergarten underwent changes that can be difficult to understand. Across the nation, states have increased the minimum age of entry into public schools, and Arkansas is no exception. Recently, a policymaker in our state asked the OEP to look into the research surrounding the question of raising the kindergarten entry age. This policy brief discusses the new requirements as well as the impact of these requirements on families and children in the short and long term by looking at recent changes in Arkansas law and studies concerning the effect of entry age on student achievemen
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