Search results for "heuristics"
showing 10 items of 191 documents
A DGS gesture dictionary for modelling on mobile devices
2017
ABSTRACTInteractive or Dynamic Geometry System (DGS) is a tool that help to teach and learn geometry using a computer-based interactive environment. Traditionally, the interaction with DGS is based on keyboard and mouse events where the functionalities are accessed using a menu of icons. Nevertheless, recent findings suggest that such a traditional model of interaction has a steep learning curve and is inadequate to develop DGS for devices with multi-touch screens. Thus, we propose a new interaction model for DGS based on a gesture dictionary which enables the construction and manipulation of geometric objects without the need of accessing a menu of icons. The dictionary is divided into thr…
Crowdfunding Models, Strategies, and Choices Between Them
2020
AbstractThe growing popularity of crowdfunding is manifested through the proliferation of thousands of platforms globally. The current chapter presents an elaborate, up-to-date, and detailed typology of crowdfunding models currently in use, as well as their main characteristics. Furthermore, it suggests some of the first frameworks developed for guiding prospective fundraisers in choosing between models. Each of the frameworks is designed for a different type of fundraiser, including model choice heuristics for organizations and consumers. The chapter concludes with some suggestions for further research and implications for practice.
Different Methods of Artificial Intelligence Used for Optimization the Turning Process
2015
In this paper, we realize a comparative study between some heuristics methods applied in turning operation in order to find optimal cutting parameters. We consider five different constraints aimed to achieve minimum total cost of machining. We have chosen the Simulated Annealing (SA) – a local search method, and Weighted-Sum Genetic Algorithm (WSGA) – a non-Pareto approach of a multi-objective optimization algorithm, based on a weighted aggregation of objectives. The aggregation may be with fixed weights or with random (variable) weights. The simulations showed that, even if it produces better results than the SA, WSGA with fixed weights, does not lead to optimum results, highlighting in th…
A Novel Artificial Mosaic Generation Technique Driven by Local Gradient Analysis
2008
Art often provides valuable hints for technological innovations especially in the field of Image Processing and Computer Graphics. In this paper we present a novel method to generate an artificial mosaic starting from a raster input image. This approach, based on Gradient Vector Flow computation and some smart heuristics, permit us to follow the most important edges maintaining at the same time high frequency details. Several examples and comparisons with other recent mosaic generation approaches show the effectiveness of our technique.
The nature of security and risk in complex socio-technical systems : a partial application of Critical Systems Heuristics (CSH) to Finnish Security S…
2011
Tämä tutkimus selventää suhteita turvallisuuden, riskien sekä kompleksisten sosio-teknisten järjestelmien välillä. Käsittely tapahtuu pääosin yhteiskunnallisella tasolla, mutta eri järjestelmiä ja niiden yleisiä sekä teoreettisia perusrakenteita tarkastellaan kokonaisuuden ymmärtämiseksi paremmin. Samalla pyritään parantamaan käsitystä niistä monista yhteisvaikutuksista joita eri järjestelmillä on toisiinsa ja miten ne vaikuttavat turvallisuuteen. Turvallisuus on tunnistettu olevan suhteellista ja käyttäytyvät eri tavalla todellisissa avoimissa järjestelmissä ja avoimessa järjestelmien ympäristössä, verrattuna yksinkertaisiin järjestelmiin. Teknologia on alati läsnä nykyaikaisissa kehittyne…
Scheduling independent stochastic tasks on heterogeneous cloud platforms
2019
International audience; This work introduces scheduling strategies to maximize the expected number of independent tasks that can be executed on a cloud platform within a given budget and under a deadline constraint. The cloud platform is composed of several types of virtual machines (VMs), where each type has a unitexecution cost that depends upon its characteristics. The amount of budget spent during the execution of a task on a given VM is the product of its execution length by the unit execution cost of that VM. The execution lengths of tasks follow a variety of standard probability distributions (exponential, uniform, halfnormal, etc.), which is known beforehand and whose mean and stand…
Correlation-Based and Contextual Merit-Based Ensemble Feature Selection
2001
Recent research has proved the benefits of using an ensemble of diverse and accurate base classifiers for classification problems. In this paper the focus is on producing diverse ensembles with the aid of three feature selection heuristics based on two approaches: correlation and contextual merit -based ones. We have developed an algorithm and experimented with it to evaluate and compare the three feature selection heuristics on ten data sets from UCI Repository. On average, simple correlation-based ensemble has the superiority in accuracy. The contextual merit -based heuristics seem to include too many features in the initial ensembles and iterations were most successful with it.
Processing privacy information and decision-making for smartphone apps among young German smartphone users
2018
While privacy behaviour is generally equated with self-disclosure, other forms of behaviour that potentially infringe an individual’s privacy, such as downloading an app, are being neglected by research. We seek to fill this gap by modelling app decision-making within a dual-process model of the attitude–behaviour relationship and the role of privacy attitudes in two kinds of information processing: (1) spontaneous, heuristic processes that rely on automated attitude activation and (2) elaborate, cognitive processes that rely on behavioural intentions to guide behaviour. We used a quasi-experimental design to investigate app decision-making processes for N = 89 participants in N = 254 decis…
A comparison study of evolutive algorithms for solving the partitioning problem in distributed virtual environment systems
2004
Fast Internet connections and the widespread use of high performance graphic cards are making Distributed Virtual Environment (DVE) systems very common nowadays. However, there are several key issues in these systems that should still be improved in order to design a scalable and cost-effective system. One of these key issues is the partitioning problem. This problem consists of efficiently assigning clients (3D avatars) to the servers in the system. In this paper, we present a comparison study of different modern heuristics for solving the partitioning problem in DVE systems, as an alternative to the ad hoc heuristic proposed in the literature. Performance evaluation results show that some…
A Comparison Study of Modern Heuristics for Solving the Partitioning Problem in Distributed Virtual Environment Systems
2003
Fast Internet connections and the widespread use of high performance graphic cards are making Distributed Virtual Environment (DVE) systems very common nowadays. However, there are several key issues in these systems that should still be improved in order to design a scalable and cost-effective system. One of these key issues is the partitioning problem. This problem consists of efficiently assigning clients (3-D avatars) to the servers in the system. In this paper, we present a comparison study of different modern heuristics for solving the partitioning problem in DVE systems, as an alternative to the ad-hoc heuristic proposed in the literature. Performance evaluation results show that som…