The Dijkstra monad has been introduced recently for capturing weakest precondition computations within the context of program verification, supported by a theorem prover. Here we give a more general description of such Dijkstra monads in a categorical setting. We first elaborate the recently developed view on program semantics in terms of a triangle of computations, state transformers, and pred...

The Dijkstra and Hoare monads have been introduced recently for capturing weakest precondition computations and computations with preand post-conditions, within the context of program verification, supported by a theorem prover. Here we give a more general description of such monads in a categorical setting. We first elaborate the recently developed view on program semantics in terms of a trian...

This paper mainly studies the eradication of the Ebola virus, proposing a scientific system, including three modules for the eradication of Ebola virus. Firstly, we build a basic model combined with nonlinear incidence rate and maximum treatment capacity. Secondly, we use the dynamic programming method and the Dijkstra Algorithm to set up M-S (storage) and several delivery locations in West Afr...

Delivery of goods is one the services used in online buying and selling process at Post Office company. Companies need a performance distribution that more time-consuming cost-efficient, so it requires determination selecting shortest path. Many algorithms have been to help find path for distributing goods, including Dijkstra Algorithm Greedy Algorithm. In this study, application two routes bet...

Nowadays, the development of „smart cities‟ with a high level of quality of life is becoming a prior challenge to be addressed. In this framework, promoting the model shift towards more reliable, greener and in general more sustainable transportation modes, namely towards a „smart mobility‟ could significantly contribute to achieve this goal. The aim of this paper is to provide users with more ...

We give an operational model of causally-ordered message-passing primitives. Based on this model, we formulate a Hoare-style proof system for causally-ordered delivery. To illustrate the use of this proof system and to demonstrate the feasibility of applying invariant-based verification techniques to algorithms that depend on causally-ordered delivery, we verify an asynchronous variant of the d...

Voronoi diagrams are fundamental data structures in computational geometry with several applications on different fields inside and outside computer science. This paper shows a CUDA algorithm to compute Voronoi diagrams on a 2D image where the distance between points cannot be directly computed in the euclidean plane. The proposed method extends an existing Dijkstra-based GPU algorithm to treat...

A shortest path search method based on ant colony algorithm is proposed. The method contracts the search space appropriately, obtaining, in a short time, a path that is as close as possible to the path obtained by the Dijkstra method (the optimum path). To improve the performance, we modify the pheromone update rule and introduce a learning strategy into the ant colony algorithm. The method obt...

We present an algorithm to find an Euclidean Shortest Path from a source vertex s to a sink vertex t in the presence of obstacles in R. Our algorithm takes O(T +m(lgm)(lg n)) time and O(n) space. Here, O(T ) is the time to triangulate the polygonal region, m is the number of obstacles, and n is the number of vertices. This bound is close to the known lower bound of O(n+m lgm) time and O(n) spac...