Search results for "TRAVEL"
showing 10 items of 402 documents
Painlevé analysis and exact solutions for the coupled Burgers system
2006
We perform the Painleve test to a system of two coupled Burgers-type equations which fails to satisfy the Painleve test. In order to obtain a class of solutions, we use a slightly modified version of the test. These solutions are expressed in terms of the Airy functions. We also give the travelling wave solutions, expressed in terms of the trigonometric and hyperbolic functions.
Das Traveling Salesman Problem
1970
Unter den Reihenfolgeproblemen hat das Traveling Salesman Problem eine besondere Bedeutung. Aus diesem Grund ist ihm der meiste Platz dieses Buches gewidmet. Haufig werden sogar die Begriffe Reihenfolgeproblem und Traveling Salesman Problem synonym verwendet.
An algorithm for the Rural Postman problem on a directed graph
1986
The Directed Rural Postman Problem (DRPP) is a general case of the Chinese Postman Problem where a subset of the set of arcs of a given directed graph is ‘required’ to be traversed at minimum cost. If this subset does not form a weakly connected graph but forms a number of disconnected components the problem is NP-Complete, and is also a generalization of the asymmetric Travelling Salesman Problem. In this paper we present a branch and bound algorithm for the exact solution of the DRPP based on bounds computed from Lagrangean Relaxation (with shortest spanning arborescence sub-problems) and on the fathoming of some of the tree nodes by the solution of minimum cost flow problems. Computation…
Price dispersion, competition, and the role of online travel agents: Evidence from business routes in the Italian airline market
2014
Abstract In this article, using data from the Italian airline market, we study the role of online travel agents (OTAs) in driving price dispersion as compared to the effect of airlines’ websites. Specifically, we investigate how distinctive factors between OTAs and airlines’ direct channels influence price dispersion. We find that after controlling for OTAs’ features related to airline competition, price dispersion should be lower in the OTA channel relative to airlines’ direct channels. On the other hand, we also find that OTAs’ features related to the presence of airline competition play in favor of higher price dispersion in such indirect channel.
Kernel manifold alignment for domain adaptation
2016
The wealth of sensory data coming from different modalities has opened numerous opportu- nities for data analysis. The data are of increasing volume, complexity and dimensionality, thus calling for new methodological innovations towards multimodal data processing. How- ever, multimodal architectures must rely on models able to adapt to changes in the data dis- tribution. Differences in the density functions can be due to changes in acquisition conditions (pose, illumination), sensors characteristics (number of channels, resolution) or different views (e.g. street level vs. aerial views of a same building). We call these different acquisition modes domains, and refer to the adaptation proble…
Large-scale random features for kernel regression
2015
Kernel methods constitute a family of powerful machine learning algorithms, which have found wide use in remote sensing and geosciences. However, kernel methods are still not widely adopted because of the high computational cost when dealing with large scale problems, such as the inversion of radiative transfer models. This paper introduces the method of random kitchen sinks (RKS) for fast statistical retrieval of bio-geo-physical parameters. The RKS method allows to approximate a kernel matrix with a set of random bases sampled from the Fourier domain. We extend their use to other bases, such as wavelets, stumps, and Walsh expansions. We show that kernel regression is now possible for data…
Evaluation of the Use of a City Center through the Use of Bluetooth Sensors Network
2019
In order to achieve the objectives of Smart Cities, public administrations need to take measures to regulate mobility, which undoubtedly requires a high level of information and sensorization. Until the implementation of the connected vehicle takes place, it is still necessary to install sensors to obtain information about mobility. Bluetooth sensors are becoming a useful tool due to the low cost of equipment and installation. The use of Bluetooth sensors in cities, with short distances between sensors, makes it necessary to propose new classification algorithms that allow the trips of pedestrians and vehicles to be differentiated. This article presents the study carried out in the city of …
An optimization approach for communal home meal delivery service
2009
Abstract: This paper is the first to discuss the communal home meal delivery problem. The problem can be modelled as a multiple travelling salesman problem with time windows, that is closely related to the well-studied vehicle routing problem with time windows. Experimental results are reported for a real-life case study from Central Finland over several alternative scenarios using the SPIDER commercial solver. The comparison with current practice reveals that a significant savings potential can be obtained using off-the-shelf optimization tools. As such, the potential for supporting real-life communal routing problems can be considered to be important for VRP practitioners.
A GIS-MCDM-based road network planning for tourism development and management in Arasbaran forest, Iran.
2019
It is very important for managers to plan a road network that meets all the requirements for tourism development and management. The aim of this study was to evaluate and modify an existing road network for tourism purposes in the Arasbaran protected area. First, the map layers of effective criteria were prepared in GIS and were standardized by a fuzzy logic approach and finally combined considering their relative importance weights obtained through pair-wise comparison technique. A suitability map was then acquired. After that, 14 different scenarios of road network were designed to access the recreational area using PEGGER extension in ArcView. Then, they were evaluated in terms of techni…
Demographic change, tourism expenditure and life cycle behavior
2015
Abstract The paper explores how demographic changes in human populations may impact on tourism decision-making of households over their life cycle. By means of hurdle models, the study focuses respectively on the decision to travel domestically or abroad and investigates if statistically significant differences exist as to the impact of age and cohort on the decision to travel and tourism expenditure. Using a vast dataset on Italian Household Expenditures over the period 1997–2007 the empirical results show that demographic aspects do have a strong effect on the tourism behaviour of families and that cohort and age effects act differently on the decision of households to make a trip and on …