Search results for " travel"

NP-completeness of the hamming salesman problem

1985

It is shown that the traveling salesman problem, where cities are bit strings with Hamming distances, is NP-complete.

The computational complexity of the relative robust shortest path problem with interval data

2004

Abstract The paper deals with the relative robust shortest path problem in a directed arc weighted graph, where arc lengths are specified as intervals containing possible realizations of arc lengths. The complexity status of this problem has been unknown in the literature. We show that the problem is NP -hard.

A class of label-correcting methods for the K shortest paths problem

2001

In this paper we deal with the problem of finding the first K shortest paths from a single origin node to all other nodes of a directed graph. In particular, we define the necessary and sufficient conditions for a set of distance label vectors, on the basis of which we propose a class of methods which can be viewed as an extension of the generic label-correcting method for solving the classical single-origin all-destinations shortest path problem. The data structure used is characterized by a set of K lists of candidate nodes, and the proposed methods differ in the strategy used to select the node to be extracted at each iteration. The computational results show that: 1. some label-correct…

The Spanning Tree based Approach for Solving the Shortest Path Problem in Social Graphs

2016

Nowadays there are many social media sites with a very large number of users. Users of social media sites and relationships between them can be modelled as a graph. Such graphs can be analysed using methods from social network analysis (SNA). Many measures used in SNA rely on computation of shortest paths between nodes of a graph. There are many shortest path algorithms, but the majority of them suits only for small graphs, or work only with road network graphs that are fundamentally different from social graphs. This paper describes an efficient shortest path searching algorithm suitable for large social graphs. The described algorithm extends the Atlas algorithm. The proposed algorithm so…

Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species

2015

Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates). Previously, morphological attributes a…

Is Participation in Tourism Market an Opportunity for Everyone? Some Evidence from Italy

2014

Exploring the main determinants of tourism participation at national and international level, the paper investigates if there are differences in tourism consumption behavior among Italian families which reflect disparities in their standard of living. To achieve this a Heckman model has been used on a huge sample of Italian households over the period 1997-2007. Results show that participation in the tourism market is strongly affected by the personal characteristics of individuals and that tourism consumption is an income sensitive good. The analysis reveals that tourism is generally a luxury good reflecting the disparities in the standard of living among Italian families. We have found tha…

Prefazione a Emmanuel Iduma, Lo sguardo di uno sconosciuto

2020

By introducing Emmanuel Iduma's travelogue across Africa, which he traveled from East to West as a member of the Trans-African project "Invisible Borders", the Preface also explains the significance and urgency of launching a new African Literature Series for the respected Milan-based independent press Francesco Brioschi Editore. The Series publishes the works of African writers from the younger generations.

The Effect of Advanced Traveller Information Systems (ATIS) on public transport demand and its uncertainty

2009

Advanced Traveller Information Systems (ATISs) include a broad range of advanced computer and communication technologies. These systems are designed to provide transit riders pre-trip and real-time information, to make better informed decisions regarding their mode of travel, planned routes and travel times. ATISs include in-vehicle displays, terminal or wayside based information centres, information by phone or mobile and internet. In this article, a Stated Preference survey has been carried out in order to know the preferences of public transport’s customers related to different ATISs and their willingness to pay in Palermo. An ordered probit demand model has been calibrated to determine …

"Formal and Thematic Influence of Travel Writing on the Novel: from the Pilgrims' Accounts to Defoe"

2008

ESPLORANDO IL MEDIOEVO: HENRY GALLY KNIGHT E LA SICILIA

2018

This essay is dedicated to the figure of Henry Gally Knight, a well-known british expert of medieval architecture, who decided to reach Sicily in 1836 to complete his Norman architecture investigations, together with the architect George Moore. During his stay in the island, besides visiting more traditional landmarks of classical antiquity, Gally Knight’s specific interests will lead him not only to study prestigious architectural complexes like Monreale and Cefalù, but also to trace the medieval vestiges even of the island’s inner parts, such as Randazzo, Maniace, Troina. Gally Knight’s tour and the esulting volumes he published – The Normans in Sicily: being a Sequel to “An architectural…