scholarly journals Trans-Dichotomous Algorithms without Multiplication —some Upper and Lower Bounds

1997 ◽  
Vol 4 (12) ◽  
Author(s):  
Andrej Brodnik ◽  
Peter Bro Miltersen ◽  
J. Ian Munro

We show that on a RAM with addition, subtraction, bitwise<br />Boolean operations and shifts, but no multiplication, there is a<br />trans-dichotomous solution to the static dictionary problem using<br />linear space and with query time sqrt(log n(log log n)^(1+o(1))). On<br />the way, we show that two w-bit words can be multiplied in<br />time (log w)^(1+o(1)) and that time Omega(log w) is necessary, and that<br />Theta(log log w) time is necessary and sufficient for identifying the<br />least significant set bit of a word.

1974 ◽  
Vol 26 (5) ◽  
pp. 1169-1172
Author(s):  
Carl David Minda

Upper and lower bounds for the capacity of planar Cantor-like sets are presented. Chebichev polynomials are the principal tool employed in the derivation of these estimates. A necessary and sufficient condition for certain planar Cantor-like sets to have positive capacity is obtained. Related one-sided capacitary estimates for more general Cantor-like sets can be found in [3, pp. 106-109]. Techniques analogous to those used in this paper yield similar results for linear Cantor-like sets which are well-known [2, pp. 150-161]. The use of Chebichev polynomials to obtain these results provides an alternate, possibly more elementary, approach to these linear problems.


1971 ◽  
Vol 3 (1) ◽  
pp. 120-154 ◽  
Author(s):  
Edward C. Van Der Meulen

The problem of transmitting information in a specified direction over a communication channel with three terminals is considered. Examples are given of the various ways of sending information. Basic inequalities for average mutual information rates are obtained. A coding theorem and weak converse are proved and a necessary and sufficient condition for a positive capacity is derived. Upper and lower bounds on the capacity are obtained, which coincide for channels with symmetric structure.


1971 ◽  
Vol 3 (01) ◽  
pp. 120-154 ◽  
Author(s):  
Edward C. Van Der Meulen

The problem of transmitting information in a specified direction over a communication channel with three terminals is considered. Examples are given of the various ways of sending information. Basic inequalities for average mutual information rates are obtained. A coding theorem and weak converse are proved and a necessary and sufficient condition for a positive capacity is derived. Upper and lower bounds on the capacity are obtained, which coincide for channels with symmetric structure.


2021 ◽  
Author(s):  
Martin Kutrib ◽  
Andreas Malcher ◽  
Christian Schneider

AbstractWe investigate finite automata whose state graphs are undirected. This means that for any transition from state p to q consuming some letter a from the input there exists a symmetric transition from state q to p consuming a letter a as well. So, the corresponding language families are subregular, and in particular in the deterministic case, subreversible. In detail, we study the operational descriptional complexity of deterministic and nondeterministic undirected finite automata. To this end, the different types of automata on alphabets with few letters are characterized. Then, the operational state complexity of the Boolean operations as well as the operations concatenation and iteration is investigated, where tight upper and lower bounds are derived for unary as well as arbitrary alphabets under the condition that the corresponding language classes are closed under the operation considered.


2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Zhen-Hang Yang ◽  
Ying-Qing Song ◽  
Yu-Ming Chu

We present the necessary and sufficient condition for the monotonicity of the ratio of the power and second Seiffert means. As applications, we get the sharp upper and lower bounds for the second Seiffert mean in terms of the power mean.


2012 ◽  
Vol 23 (07) ◽  
pp. 1250072 ◽  
Author(s):  
MANUEL FERNÁNDEZ-LÓPEZ ◽  
EDUARDO GARCÍA-RÍO

Necessary and sufficient conditions for a gradient Ricci soliton to be Einstein are given, showing that they can be expressed in terms of upper and lower bounds on the behavior of the Ricci tensor when evaluated on the gradient of the potential function of the soliton.


Author(s):  
Benj Hellie

Recent neo-Anscombean work in praxeology (aka ‘philosophy of practical reason’), salutarily, shifts focus from an alienated ‘third-person’ viewpoint on practical reason to an embedded ‘first-person’ view: for example, the ‘naive rationalizations’ of Michael Thompson, of form ‘I am A-ing because I am B-ing’, take up the agent’s view, in the thick of action. Less salutary, in its premature abandonment of the first-person view, is an interpretation of these naive rationalizations as asserting explanatory links between facts about organically structured agentive processes in progress, followed closely by an inflationary project in ‘practical metaphysics’. If, instead, praxeologists chase first-personalism all the way down, both fact and explanation vanish (and with them, the possibility of metaphysics): what is characteristically practical is endorsement of nonpropositional imperatival content, chained together not explanatorily, but through limits on intelligibility. A connection to agentive behavior must somehow be reestablished—but this can (and can only) be done ‘transcendentally’.


Mathematics ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 17 ◽  
Author(s):  
Abdollah Alhevaz ◽  
Maryam Baghipur ◽  
Hilal A. Ganie ◽  
Yilun Shang

The generalized distance matrix D α ( G ) of a connected graph G is defined as D α ( G ) = α T r ( G ) + ( 1 − α ) D ( G ) , where 0 ≤ α ≤ 1 , D ( G ) is the distance matrix and T r ( G ) is the diagonal matrix of the node transmissions. In this paper, we extend the concept of energy to the generalized distance matrix and define the generalized distance energy E D α ( G ) . Some new upper and lower bounds for the generalized distance energy E D α ( G ) of G are established based on parameters including the Wiener index W ( G ) and the transmission degrees. Extremal graphs attaining these bounds are identified. It is found that the complete graph has the minimum generalized distance energy among all connected graphs, while the minimum is attained by the star graph among trees of order n.


2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Hui Lei ◽  
Gou Hu ◽  
Zhi-Jie Cao ◽  
Ting-Song Du

Abstract The main aim of this paper is to establish some Fejér-type inequalities involving hypergeometric functions in terms of GA-s-convexity. For this purpose, we construct a Hadamard k-fractional identity related to geometrically symmetric mappings. Moreover, we give the upper and lower bounds for the weighted inequalities via products of two different mappings. Some applications of the presented results to special means are also provided.


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