Results 261 to 270 of about 5,883,213 (294)

Hierarchies of Computable groups and the word problem

Journal of Symbolic Logic, 1966
The word problem for groups was first formulated by M. Dehn [1], who gave a solution for the fundamental groups of a closed orientable surface of genus g ≧ 2. In the following years solutions were given, for example, for groups with one defining relator [2], free groups, free products of groups with a solvable word problem and, in certain cases, free ...
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The Role Hierarchy Mining Problem: Discovery of Optimal Role Hierarchies

2008 Annual Computer Security Applications Conference (ACSAC), 2008
Role hierarchies are fundamental to the role based access control (RBAC) model. The notion of role hierarchy is a well understood concept that allows senior roles to inherit the permissions of the corresponding junior roles. Role hierarchies further ease the burden of security administration, as there is no need to explicitly specify and maintain a ...
Qi Guo, Jaideep Vaidya, Vijayalakshmi Atluri   +2 more
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The Compatibility Problem for Hierarchies

IFAC Proceedings Volumes, 1996
Abstract A survey on the notion of hierarchy covers a large scope of fundamental sources. Cultural, religious and philosophical contexts have used it since ancient times as a concept essential for civilization. There it comprises also forms, like structure and process, which are tom apart in modern times. The author expresses bewildering over the way
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The Hierarchy Problem and the Cosmological Constant Problem Revisited

2018
Foundations of physics 49(9), 915 - 971 (2019).
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Gender — and the problem of hierarchy

Ethnos, 1990
This article is the product of a focussed reading of Louis Dumont with a view to two particular interests: modernity and the place of gender not only within modern discourse, but also in modern practice. Though polemical in form, the intention is to shed new light on the ongoing debates of gender by addressing them within Dumont's theoretical framework.
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Hierarchies of polynomially solvable satisfiability problems

Annals of Mathematics and Artificial Intelligence, 1996
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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On the “Hierarchy Problem” in Physics

PHYSICS Journal: Theoretical and Experimental Studies
Modern physics describes nature using four fundamental forces: electromagnetism, the strong nuclear force, the weak nuclear force, and gravity. Gravity is weak compared to the forces that govern atoms and particles. This discrepancy is known in physics as the “hierarchy problem.” Physics cannot explain why gravity doesn’t play any significant role in ...
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Optimization Problems in the Polynomial-Time Hierarchy

2006
This talk surveys work on classifying the complexity and approximability of problems residing in the Polynomial-Time Hierarchy, above the first level. Along the way, we highlight some prominent natural problems that are believed – but not yet known – to be $\Sigma^p_2$-complete.
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Multi-component generalized Gerdjikov–Ivanov integrable hierarchy and its Riemann–Hilbert problem

Nonlinear Analysis: Real World Applications, 2022
Tiecheng Xia, Tongshuai Liu
exaly  

Dimensional regularization, Wilsonian RG, and the naturalness and hierarchy problem

Physical Review D, 2022
Neda Darvishi, Vincenzo Branchina, Carlo Branchina   +2 more
exaly