Search results for " search"
showing 10 items of 654 documents
Exploring User Behavior in Destination Websites: An Application of Web Mining Techniques
2021
The development of the Internet has so strongly affected the way a tourist destination can be promoted that portals now play an important role in defining the marketing strategies of tourist destinations. Hence, investigating website surfing behavior has become crucial to understanding the needs of potential tourists. Using Web Mining techniques, our study explores the information-seeking behavior of those who log on to a website promoting the island of Sicily, a well known tourist destination in the South of Italy. The study explores whether a tourist’s country of origin affects their information needs and surfing behavior. Actually, our results do show differences in behavior between user…
Change-point estimation in piecewise constant regression models with random effects
2014
We propose an iterative algorithm to estimate change-points in general regression models. The algorithm avoids grid search to obtain maximum likelihood estimates, and thus it guarantees moderate computational time regardless of the sample size and the number of change-points to be estimated. Furthermore, it allows estimation in random effects models, where grid search is unfeasible. We present the proposed approach in practice by analyzing variations of lung functionality on a sample of transplant recipients.
A beam search algorithm for minimizing crane times in premarshalling problems
2022
The premarshalling problem consists of sorting the containers placed in a bay of the container yard so that they can be retrieved in the order in which they will be required. We study the premarshalling problem with crane time minimization objective and develop a beam search algorithm, with some new elements adapted to the characteristics of the problem, to solve it. We propose various evaluation criteria, depending on the type of container movement, for its local evaluation; a new heuristic algorithm including local search for blue its global evaluation; and several new dominance rules. The computational study shows the contribution of each new element. The performance of the complete algo…
How do university students’ web search behavior, website characteristics, and the interaction of both influence students’ critical online reasoning?
2020
The Internet has become one of the main sources of information for university students’ learning. Since anyone can disseminate content online, however, the Internet is full of irrelevant, biased, or even false information. Thus, students’ ability to use online information in a critical-reflective manner is of crucial importance. In our study, we used a framework for the assessment of students’ critical online reasoning (COR) to measure university students’ ability to critically use information from online sources and to reason on contentious issues based on online information. In addition to analyzing students’ COR by evaluating their open-ended short answers, we also investigated the stude…
Intrinsic backgrounds from Rn and Kr in the XENON100 experiment
2018
In this paper, we describe the XENON100 data analyses used to assess the target-intrinsic background sources radon ([InlineMediaObject not available: see fulltext.]), thoron ([InlineMediaObject not available: see fulltext.]) and krypton ([InlineMediaObject not available: see fulltext.]). We detail the event selections of high-energy alpha particles and decay-specific delayed coincidences. We derive distributions of the individual radionuclides inside the detector and quantify their abundances during the main three science runs of the experiment over a period of ∼4years, from January 2010 to January 2014. We compare our results to external measurements of radon emanation and krypton concentr…
Search for heavy neutrinos with the T2K near detector ND280
2019
This paper reports on the search for heavy neutrinos with masses in the range 140<MN<493 MeV/c2 using the off-axis near detector ND280 of the T2K experiment. These particles can be produced from kaon decays in the standard neutrino beam and then subsequently decay in ND280. The decay modes under consideration are N→ℓ±απ∓ and N→ℓ+αℓ−β(−)ν(α,β=e,μ). A search for such events has been made using the Time Projection Chambers of ND280, where the background has been reduced to less than two events in the current dataset in all channels. No excess has been observed in the signal region. A combined Bayesian statistical approach has been applied to extract upper limits on the mixing elements of heav…
Beta-spectrum shapes of forbidden β decays
2018
The neutrinoless [Formula: see text] decay of atomic nuclei continues to attract fervent interest due to its potential to confirm the possible Majorana nature of the neutrino, and thus the nonconservation of the lepton number. At the same time, the direct dark matter experiments are looking for weakly interacting massive particles (WIMPs) through their scattering on nuclei. The neutrino-oscillation experiments on reactor antineutrinos base their analyses on speculations of [Formula: see text]-spectrum shapes of nuclear decays, thus leading to the notorious “reactor antineutrino anomaly.” In all these experimental efforts, one encounters the problem of [Formula: see text]-spectrum shapes of…
Evolución de la investigación sobre actividad física en el medio natural en educación física: Resultados en Web of ScienceTM desde 1990 a 2016
2017
Monográfico con el título: "Actividades Físicas en el Medio Natural (1ª parte)" Resumen basado en el de la publicación Título, resumen y palabras clave también en inglés Se pretende analizar la evolución del número de publicaciones sobre actividad física en el medio natural en educación física. Para ello, se realizó una búsqueda bibliográfica en la base de datos Web of ScienceTM desde 1990 hasta 2016. Los términos de búsqueda usados se basaron en dos conceptos: 1) actividad física en el medio natural y 2) educación física. Se encontraron un total de 116 resultados, con una media de 4,3 publicaciones por año, observándose una tendencia a aumentar el número de publicaciones a lo largo de los …
On the Bias of Syntactic Geometric Recombination in Genetic Programming and Grammatical Evolution
2015
For fixed-length binary representations as used in genetic algorithms, standard recombination operators (e.g.,~one-point crossover) are unbiased. Thus, the application of recombination only reshuffles the alleles and does not change the statistical properties in the population. Using a geometric view on recombination operators, most search operators for fixed-length strings are geometric, which means that the distances between offspring and their parents are less than, or equal to, the distance between their parents. In genetic programming (GP) and grammatical evolution (GE), the situation is different since the recombination operators are applied to variable-length structures. Thus, most r…
A hybrid evolution strategy for the open vehicle routing problem
2010
This paper presents a hybrid evolution strategy (ES) for solving the open vehicle routing problem (OVRP), which is a well-known combinatorial optimization problem that addresses the service of a set of customers using a homogeneous fleet of non-depot returning capacitated vehicles. The objective is to minimize the fleet size and the distance traveled. The proposed solution method manipulates a population of @m individuals using a (@m+@l)-ES; at each generation, a new intermediate population of @l offspring is produced via mutation, using arcs extracted from parent individuals. The selection and combination of arcs is dictated by a vector of strategy parameters. A multi-parent recombination …