Search results for "modeling"
showing 10 items of 4489 documents
Serial In-network Processing for Large Stationary Wireless Sensor Networks
2017
International audience; In wireless sensor networks, a serial processing algorithm browses nodes one by one and can perform different tasks such as: creating a schedule among nodes, querying or gathering data from nodes, supplying nodes with data, etc. Apart from the fact thatserial algorithms totally avoid collisions, numerous recent works have confirmed that these algorithms reduce communications andconsiderably save energy and time in large-dense networks. Yet, due to the path construction complexity, the proposed algorithmsare not optimal and their performances can be further enhanced. To do so, in the present paper, we propose a new serial processing algorithm that, in most of the case…
A hybrid genetic algorithm for the resource-constrained project scheduling problem
2008
Abstract In this paper we propose a Hybrid Genetic Algorithm (HGA) for the Resource-Constrained Project Scheduling Problem (RCPSP). HGA introduces several changes in the GA paradigm: a crossover operator specific for the RCPSP; a local improvement operator that is applied to all generated schedules; a new way to select the parents to be combined; and a two-phase strategy by which the second phase re-starts the evolution from a neighbour’s population of the best schedule found in the first phase. The computational results show that HGA is a fast and high quality algorithm that outperforms all state-of-the-art algorithms for the RCPSP known by the authors of this paper for the instance sets j…
Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation
2010
This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme is developed for the specific crane, considering the saturation phenomena of the system and practical implementation. This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme…
Contributions to the knowledge base on PV performance: Evaluation of the operation of PV systems using different technologies installed in southern N…
2011
To assist in establishing an accepted knowledge base on PV-modules and systems performance using a representative range of technologies, devices have to be installed at diverse locations, covering a broad range of environmental conditions. For the example of a high latitude location, modules and systems are installed and under investigation in southern Norway (Kristiansand region) by the University of Agder in cooperation with industrial partners. This paper presents first results of the analysis of module performance. The operational behavior of the modules is used to derive a modeling scheme applicable for performance prediction. This use is demonstrated by giving the expected annual perf…
Effects of school climate and teacher self-efficacy on job satisfaction of mostly STEM teachers: a structural multigroup invariance approach
2020
Abstract Background Identification and retention of effective teachers in STEM education play cardinal roles in teacher recruitment exercises worldwide. Studies on factors that characterize effective teachers have therefore gained popularity in recent times. Teacher self-efficacy, job satisfaction and school climate are among other factors that have attracted global attention. Thus, proper understanding of the relations between these factors is equally important. The purpose of this study is to validate and cross-validate a model of direct/indirect effects of school climate and teacher self-efficacy on job satisfaction. Results The data used for the current study are extracted from a public…
Supporting the Sustainable Energy Transition in the Canary Islands: Simulation and Optimization of Multiple Energy System Layouts and Economic Scenar…
2021
The Canary Islands have great potential for the implementation of sustainable energy systems due to its availability of natural resources. The archipelago is not connected to the mainland electricity grid and the current generation system is mainly based on traditional fossil fuel. Therefore, the islands strongly dependent on fuel importations, with high costs due to logistics. Furthermore, due to the inadequate coverage of residential heating and cooling needs, the per capita energy consumption is far below the Spanish national average. This occurrence has inspired an intense debate on the current development model of the Canary Archipelago, which has led to the implementation of actions a…
Integration of thermal building simulation and VR techniques for sustainable building projects
2013
Déjà présent sur HAL mais sans le fichier pdf; The importance of energy efficiency and integration of advances in building design and VR technology have led this research to focus on thermal simulation results visualized in a virtual environment to optimize building design. This paper combines the principle of integration for thermal calculation and scientific visualization in VR. The method is to use CAD models (extensively used in architectural design) to analyze a building's thermal performance and visualize it, as well as simulating it through VR technology. Interaction between users and objects in a virtual world are certainly through techniques of visualization metaphors. The object o…
BICKEL–ROSENBLATT TEST FOR WEAKLY DEPENDENT DATA
2012
The aim of this paper is to analyze the Bickel–Rosenblatt test for simple hypothesis in case of weakly dependent data. Although the test has nice theoretical properties, it is not clear how to implement it in practice. Choosing different band-width sequences first we analyze percentage rejections of the test statistic under H0 by some empirical simulation analysis. This can serve as an approximate rule for choosing the bandwidth in case of simple hypothesis for practical implementation of the test. In the recent paper [12] a version of Neyman goodness-of-fit test was established for weakly dependent data in the case of simple hypotheses. In this paper we also aim to compare and discuss the …
Interactive roll stabilization comparative analysis for large yacht: gyroscope versus active fins
2020
The problem of the active stabilization of ship motions is particularly important in the case of pleasure boats or in any case of passenger ships, since the commercial value of the ship is directly related to the comfort of the load transported in this case “people”, considered as stresses induced on them by the vessel movements, with particular attention to roll, given the ship geometric characteristics. Naval architects developed trough the years different solutions to reduce the roll of the ship, and consequentially to increase the passengers comfort, and the development of this solutions followed the progress of technology. Active fins have been the most used, but now the gyroscope solu…
Developmental trajectories of school burnout: Evidence from two longitudinal studies
2014
Abstract To examine school burnout trajectories, in Study 1, 15-year-old adolescents ( N = 614) completed the School Burnout Inventory twice during their final term of comprehensive school and twice after the transition to upper secondary high school or vocational school. In Study 2, school burnout in 17-year-old adolescents was measured twice annually ( N = 575) during their upper secondary education. In Study 1, growth mixture modeling for school burnout yielded a four-latent-group solution: 60% of the adolescents showed a low and stable level of school burnout, 29% increasing burnout, 3% strongly increasing burnout and 8% high-decreasing school burnout. In Study 2, we identified two la…