5,272 research outputs found
Programming in logic without logic programming
In previous work, we proposed a logic-based framework in which computation is
the execution of actions in an attempt to make reactive rules of the form if
antecedent then consequent true in a canonical model of a logic program
determined by an initial state, sequence of events, and the resulting sequence
of subsequent states. In this model-theoretic semantics, reactive rules are the
driving force, and logic programs play only a supporting role.
In the canonical model, states, actions and other events are represented with
timestamps. But in the operational semantics, for the sake of efficiency,
timestamps are omitted and only the current state is maintained. State
transitions are performed reactively by executing actions to make the
consequents of rules true whenever the antecedents become true. This
operational semantics is sound, but incomplete. It cannot make reactive rules
true by preventing their antecedents from becoming true, or by proactively
making their consequents true before their antecedents become true.
In this paper, we characterize the notion of reactive model, and prove that
the operational semantics can generate all and only such models. In order to
focus on the main issues, we omit the logic programming component of the
framework.Comment: Under consideration in Theory and Practice of Logic Programming
(TPLP
Path planning algorithm for a car like robot based on MILP method
This project is presents an algorithm for path planning optimal routes mobile robot
“like a car” to a target in unknown environment. The proposed algorithm allows a
mobile robot to navigate through static obstacles and finding the path in order to
reach the target without collision. This algorithm provides the robot the possibility to
move from the initial position to the final position (target). The proposed path
finding strategy is to use mathematical programming techniques to find the optimal
path between to state for mobile robot designed in unknown environment with
stationary obstacles. Formulation of the basic problems is to have the vehicle moved
from the initial dynamic state to a state without colliding with each other, while at
the same time avoiding other stationary obstacles. It is shown that this problem can
be rewritten as a linear program with mixed integer / linear constraints that account
for the collision avoidance. This approach is that the path optimization can be easily
solved using the CPLEX optimization software with AMPL interface / MATLAB.
The final phases are the design and build coalitions of linear programs and binary
constraints to avoid collision with obstacles by Integer Mixed Linear Program
(MILP). The findings of this research have shown that the MILP method can be used
in the path planning problem in terms of finding a safe and shortest path. This has
been combined with collision avoidance constraints to form a mixed integer linear
program, which can be solved by a commercial software package
Assessment of bivariate normality
There are three methods, which are most commonly used to assess the bivariate normality of paired data, two of which are also used to assess the multivariate normality. Nevertheless, none of the methods is very efficient or conclusive in their assessment of bivariate normality. In this thesis we are proposing a new method to test bivariate normality. This new method makes use of a set of if and only if conditions inherent in the theory of bivariate normal distribution. The proposed new method is highly efficient, accurate, and very easy to apply using any available standard statistical software
The Plane-Wave/Super Yang-Mills Duality
We present a self-contained review of the Plane-wave/super-Yang-Mills
duality, which states that strings on a plane-wave background are dual to a
particular large R-charge sector of N=4, D=4 superconformal U(N) gauge theory.
This duality is a specification of the usual AdS/CFT correspondence in the
"Penrose limit''. The Penrose limit of AdS_5 S^5 leads to the maximally
supersymmetric ten dimensional plane-wave (henceforth "the'' plane-wave) and
corresponds to restricting to the large R-charge sector, the BMN sector, of the
dual superconformal field theory. After assembling the necessary background
knowledge, we state the duality and review some of its supporting evidence. We
review the suggestion by 't Hooft that Yang-Mills theories with gauge groups of
large rank might be dual to string theories and the realization of this
conjecture in the form of the AdS/CFT duality. We discuss plane-waves as exact
solutions of supergravity and their appearance as Penrose limits of other
backgrounds, then present an overview of string theory on the plane-wave
background, discussing the symmetries and spectrum. We then make precise the
statement of the proposed duality, classify the BMN operators, and mention some
extensions of the proposal. We move on to study the gauge theory side of the
duality, studying both quantum and non-planar corrections to correlation
functions of BMN operators, and their operator product expansion. The important
issue of operator mixing and the resultant need for re-diagonalization is
stressed. Finally, we study strings on the plane-wave via light-cone string
field theory, and demonstrate agreement on the one-loop correction to the
string mass spectrum and the corresponding quantity in the gauge theory. A new
presentation of the relevant superalgebra is given.Comment: RevTeX 4 format; 91 pages; 7 figures. Prepared for Reviews of Modern
Physics. Please send comments to darius, jabbari @ itp.stanford.edu. v3:
Minor typos fixe
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