Search results for "SIMULATION"

Complex Adaptive Systems and Agent-Based Modelling

2015

In a labour–education market system, there are many individuals and firms with adaptive behaviour. As we have seen in the previous chapter, networks are prevalent in LEMS and play an important role in many decisions of its actors. Thus, LEMS can be analysed as a complex adaptive system (CAS). Agent-based modelling (ABM) is typically used for such purposes, and the next chapter will dig into details of various ways of applying ABM in modelling LEMS. To be ready for it, we first have to understand the motivation behind and the details of this method. This is what will be discussed here.

Pašbraucošu automašīnu algoritmu testēšanas iespējas autosacīkšu simulatoros

2020

Dažādi autovadītāju asistenti arvien vairāk iesaistās automašīnu vadīšanā. Pamazām parādās arī iebūvēti autopiloti, taču radīt pašbraucošas mašīnas ir ļoti dārgi un sarežģīti. Darbā tiks pētīts, kādus pašbraucošu automašīnu algoritmus un tehnoloģijas ir iespējams attīstīt uz autosacīkšu simulatoriem, izmantojot modificētas datora perifērijas ierīces un mikrokontrolierus. Algoritmu mērķis ir ne vien korekti veikt noteiktu maršrutu, bet arī spēt to izdarīt pēc iespējas ātrāk, maksimāli maz atpaliekot no cilvēka vadīta transporta. Algoritmus realizēs izmantojot mikrokontrolierus, kas pados signālus specializētām datorspēļu perifērijas ierīcēm, kas ar datoru sazināsies kā parasts datorspēļu kon…

Life cycle assessment of solar communities

2020

Abstract This study presents the comparison of the life cycle performance of two different urban energy systems, applied to a large mixed-use community, in Calgary (Canada). The two systems investigated consist of an energy efficient conventional system, using heat pumps for heating, cooling and domestic hot water; the second design widely deploys solar thermal panels coupled to district heating infrastructure and a borehole seasonal thermal storage. The analysis is based on the Life Cycle Assessment methodology and includes the stages of raw materials and energy supply, system manufacturing, use stage of the systems, generation and use of energy on-site, maintenance and components’ substit…

Car sequencing versus mixed-model sequencing: A computational study

2014

Abstract The paper deals with the two most important mathematical models for sequencing products on a mixed-model assembly line in order to minimize work overload the mixed-model sequencing (MMS) model and the car sequencing (CS) model. Although both models follow the same underlying objective, only MMS directly addresses the work overload in its objective function. CS instead applies a surrogate objective using so-called sequencing rules which restrict labor-intensive options accompanied with the products in the sequence. The CS model minimizes the number of violations of the respective sequencing rules, which is widely assumed to lead to minimum work overload. This paper experimentally co…

Is the Ghosh model interesting?

2009

International audience; The overall value of the Ghosh model is appraised. Its treatment of quantities and prices is scrutinized by examining the variant with data in quantities and prices, and the variant with data in value and price indexes. The methodology involves returning to the accounting equations and shows that: (i) the Ghosh model offers solutions of limited interest, being incapable of providing prices or price indexes separately from quantities; (ii) what is taken to be the equation of Ghosh's value model is actually that of Ghosh's physical model; (iii) the Ghosh model may serve for cost-push exercises, but the dual of the Leontief model performs the same task in a much simpler…

A Highly Flexible Trajectory Model Based on the Primitives of Brownian Fields—Part I: Fundamental Principles and Implementation Aspects

2015

A fundamental drawback of synthetic mobility models is that the spatial configuration of the path is determined by the temporal features of the mobile station (MS), such as its speed. This is, however, not true in reality. This first part of our paper establishes a new approach for generating fully spatial random trajectory (mobility) models to which different speed scenarios can be applied. We employ the new approach to the proposal of a highly flexible trajectory model based on the primitives (integrals) of Brownian fields (BFs). We construct a drifted partial random bridge from a given starting point to a random terminating point in the 2D plane. If the bridge is partially established, a…

MIRO : des trajectoires individuelles à la ville en mouvement

2010

Children’s Interactions Within a Virtual Reality Environment for Learning Chemistry

2017

This paper presents a virtual reality based solution for learning. Multimodal interactions are proposed to support students’ engagement through active experimentation and reflective observation. Students tasks are provided within an immersive virtual outdoor environment created using a human-centred design approach. Junior high school teachers and students between ages 14 and 16 were involved in design and test activities. Observations, video recordings, and interviews were used in data collection. Three interaction modalities were provided and tested: visual, auditory and kinesthetic/tangible interactions. The students involved in user testing showed great interest to learn in such an envi…

Towards a Formal Analysis of MQtt Protocol in the Context of Communicating Vehicles

2017

International audience; The paper presents a formal approach to model, analyze, and verify a variant of Message Queue Telemetry Transport protocol (MQtt), dedicated to communicating vehicles (MQtt-CV) that send collected data to automotive infrastructures(subscribers). Our formal approach is based on Promela language and its system verification tool, the model checker SPIN. We propose a slight modification of MQtt protocol to reduce the big volume of data collected and sent by vehicles to infrastructures. Indeed, in the original version of MQtt protocol, when a broker receives data from publishers, it sends them directly to its subscribers without any filtration. As consequence, subscribers…

Verifying a medical protocol with temporal graphs: the case of a nosocomial disease.

2014

Abstract Objective Our contribution focuses on the implementation of a formal verification approach for medical protocols with graphical temporal reasoning paths to facilitate the understanding of verification steps. Materials and methods Formal medical guideline specifications and background knowledge are represented through conceptual graphs, and reasoning is based on graph homomorphism. These materials explain the underlying principles or rationale that guide the functioning of verifications. Results An illustration of this proposal is made using a medical protocol defining guidelines for the monitoring and prevention of nosocomial infections. Such infections, which are acquired in the h…