Search results for "Computer Science Application"
showing 10 items of 3998 documents
Opaque Distribution Channels for Competing Service Providers: Posted Price vs. Name-Your-Own-Price Mechanisms
2014
Opaque selling has been widely adopted by service providers in the travel industry to sell off leftover capacity under stochastic demand. We consider a two-stage model to study the impact of different selling mechanisms, posted price (PP) versus name-your-own-price (NYOP), of an opaque reseller on competing service providers who face forward-looking customers. We find that in this environment, providers prefer that the opaque reseller uses a posted price instead of a bidding model. This is because the ability to set retail prices is critical for extracting surplus from customers who wait to purchase from the reseller. Such surplus extraction enables providers to set high prices for advance…
Numerical and Experimental Study of a Novel Concept for Hydraulically Controlled Negative Loads
2016
This paper presents a numerical and experimental investigation of a novel concept that eliminates oscillations in hydraulic systems containing a counterbalance valve in series with a pressure compensated flow supply. The concept utilizes a secondary circuit where a low-pass filtered value of the load pressure is generated and fed back to the compensator of the flow supply valve. The novel concept has been implemented on a single boom actuated by a cylinder. A nonlinear model of the system has been developed and an experimental verification shows good correspondence between the model and the real system. The model is used for a parameter study on the novel concept. From the study it is found…
Levels and Changes of Physical Activity in Adolescents during the COVID-19 Pandemic: Contextualizing Urban vs. Rural Living Environment
2020
The COVID-19 pandemic and the social distancing implemented shortly after influence physical activity levels (PALs). The purpose of this investigation was to evaluate the changes in PAL and factors associated with PALs among Croatian adolescents while considering the impact of community (urban vs. rural living environment). The sample included 823 adolescents (mean age: 16.5 ±
Molecular Mechanisms of the Blockage of Glioblastoma Motility
2021
Glioblastoma (GBM) is the most common and lethal brain tumor. GBM has a remarkable degree of motility and is able to infiltrate the healthy brain. In order to perform a rationale-based drug-repositioning study, we have used known inhibitors of two small Rho GTPases, Rac1 and Cdc42, which are upregulated in GBM and are involved in the signaling processes underlying the orchestration of the cytoskeleton and cellular motility. The selected inhibitors (R-ketorolac and ML141 for Cdc42 and R-ketorolac and EHT 1864 for Rac1) have been successfully employed to reduce the infiltration propensity of GBM in live cell imaging studies. Complementarily, all-atom simulations have elucidated the molecular …
Automated Railway Signs Detection. Preliminary Results
2019
Abstract Nowadays safety in railways is mostly achieved by automated system technologies such as ERTMS/ETCS. Nevertheless, on local railways (suburban and regional lines) several tasks still depend on the choices and actions of a human crew. With the aim to improve safety in such type of railways, this research proposes a system for the automatic detection and recognition of railway signs by means of the digital image processing technique. First field applications, carried out on the Italian railway network, show that the proposed system is very accurate (the percentage of correctly detected railway signs is about 97%), even at high train speeds.
The effect of writing modality on recollection in children and adolescents
2019
We set out to assess the extent to which writing modality affects recollection in children and adolescents. We examined 10- to 11-year-old children’s (N = 63) and 16-year-old adolescents’ (N = 43) handwriting, keyboarding with a laptop computer and keyboarding with a touchscreen tablet computer or mobile phone in a within-subjects experimental design. Participants were instructed to write down stories dictated to them in the three writing modalities. Recollection of the stories was assessed using free recall of details in the stories. The results indicate that the writing modality affects recollection, handwriting leading to better recollection. However, currently, digital writing tools are…
Teoría de la educación : educación y cultura en la sociedad de la información
2011
Se exponen las principales perspectivas en el estudio del comportamiento informacional: la perspectiva del usuario y la del sistema. En el primer caso, se asume una visión global del proceso de búsqueda de información y se desarrollan modelos teóricos y metodológicos para guiar la investigación en este campo. Se presentan como ejemplo la teoría del Sense-Making de Brenda Dervin y el modelo de Proceso de Búsqueda de Información de Carol Kuhlthau. En el segundo caso, se asume una perspectiva parcial del proceso de búsqueda de información, centrándose fundamentalmente en las transacciones entre usuario y el sistema o entre el usuario y la información. Se describen los estudios del uso de recur…
Optimal Resource Allocation in Multi-Hop Networks: Contention vs. Scheduling
2014
CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) is actually the most used method in ad-hoc networks for transmitting on a contending medium, even if it shows poor performance in presence of hidden nodes. To increase performance, we propose an algorithm that combines CSMA and TDMA (Time Division Multiple Access) approaches. The adopted solution consists of grouping contending nodes in non-interfering subsets and granting a different numbers of time slots to different groups, while using the CSMA to manage medium access among nodes belonging to the same subset. An optimization procedure to assign the time slots to each subset of nodes and to find an equilibrium between contention …
Investigation of a Gravel-Bed River’s Pattern Changes: Insights from Satellite Images
2021
Changes in river pattern have been documented in the literature. The recognition of islands and vegetated patches, which is indicative of the evolution processes, requires simultaneous information at different points and at different times and field studies are still difficult and scarce. The present work, focusing the attention on a gravel-bed river, explores the possibility to conduct a first-step pattern changes analysis by identifying the evolution of the morphological features and taking information of islands and vegetated patches from satellite images easily available from Google Earth. The study is conducted by combining the information taken from both the satellite images and the f…
CAMBIO DE ACTITUDES Y VALORES ANTE LA ENERGÍA TRAS EL USO DE UN JUEGO DE ROL
2010
Los juegos de rol en educación se han definido como dramatizaciones que se vertebran en torno a una situación concreta y utilizan la asignación de papeles a alumnos, quienes deberán defender con argumentos una opinión (previamente perfilada) frente a un problema. Cada vez más utilizados en la educación formal y no formal, destacan entre sus ventajas el convertir lo lúdico en aprendizaje, potenciar el aprendizaje de actitudes y valores y la conexión que se realiza con la vida real entre otros. La utilización de un juego de rol en una investigación educativa sobre cambio de actitudes y valores ante los recursos energéticos cuyos resultados educativos fueron positivos, permitió repetir dicha i…