Divisor

About: Divisor is a research topic. Over the lifetime, 2462 publications have been published within this topic receiving 21394 citations. The topic is also known as: factor & submultiple.

On Finite Groups Having Perfect Order Subsets

Abstract: A finite group G is said to be a POS-group if for each x in G the cardinality of the set {y ∈ G|o(y )= o(x)} is a divisor of the order of G. In this paper we study some of the properties of arbitrary POS-groups, and construct a couple of new families of nonabelian POS-groups. We also prove that the alternating group An, n ≥ 3, is not a POS-group.

Toric Calabi-Yau Fourfolds Duality Between N=1 Theories and Divisors that Contribute to the Superpotential *

Abstract: We study issues related to F-theory on Calabi-Yau fourfolds and its duality to heterotic theory for Calabi–Yau threefolds. We discuss principally fourfolds that are described by reflexive polyhedra and show how to read off some of the data for the heterotic theory from the polyhedron. We give a procedure for constructing examples with given gauge groups and describe some of these examples in detail. Interesting features arise when the local pieces are fitted into a global manifold. An important issue is how to compute the superpotential explicitly. Witten has shown that the condition for a divisor to contribute to the superpotential is that it have arithmetic genus 1. Divisors associated with the short roots of non-simply laced gauge groups do not always satisfy this condition while the divisors associated to all other roots do. For such a ‘dissident’ divisor we distinguish cases for which χ(OD) > 1 corresponding to an X that is not general in moduli (in the toric case this corresponds to the existence of non-toric parameters). In these cases the ‘dissident’ divisor D does not remain an effective divisor for general complex structure. If however χ(OD) ≤ 0, then the divisor is general in moduli and there is a genuine instability.

On perfect and near-perfect numbers

Abstract: We call positive integer n a near-perfect number, if it is sum of all its proper divisors, except of one of them ("redundant divisor"). We prove an Euclid-like theorem for near-perfect numbers and obtain some other results for them.

Receiver architecture eliminating static and dynamic DC offset errors

Abstract: The present invention provides a receiver frontend that eliminates static and dynamic DC errors and has improved second order intermodulation distortion (IMD2) performance. The receiver frontend includes a first mixer that multiplies a received signal and a first local oscillator (LO) signal to produce an intermediate frequency (IF) signal. A second mixer multiplies the IF signal and a second LO signal to produce an output signal. A first divider circuit divides a reference signal from a reference oscillator by a first divisor N to produce the first LO signal, and a second divider circuit divides the reference signal by a second divisor M to produce the second LO signal. Preferably, the first and second divisors N and M are each integers greater than one (1), and the second divisor M is not an integer multiple of the first divisor N.

Divisor transform type high-speed electronic division system

Abstract: An electronic network division system is operated responsive to signals representing divisors and dividends. An input divisor signal is divided into a given number (N) of integers, the number (N) being selected on a basis of a desired accuracy index. Each divided signal is a transform of a divisor which is read from one of (N) number of read-only memories, there being a separate read-only memory for each of the given number (N) of integers. Each of said given number of transformed divisor signals is separately multiplied by a dividend signal to produce (N) number of multiplication products. Each of these multiplication product signals is divided into high and low subproduct signals and applied to a corresponding one of (N) number of adders. A high subproduct signal from one multiplication product is added in the adding means to a low subproduct signal from another multiplication product.