Search results for "Simulation"
showing 10 items of 5095 documents
A force measuring based strategy for failure prevention in incremental forming
2006
Abstract Incremental forming processes show a number of advantages compared to the traditional processes but, at the same time, some drawbacks are clearly known. Current problems, include the slowness of the process, low accuracy and a lack of knowledge in the field of material formability. This paper is focused on the latter issue: an industrially oriented methodology for detecting the approach of failure in incremental forming is proposed. The approach is based on the analysis of the trend of the forming force in order to assess whether the process can be run safely. If not, a proper strategy, to avoid material failure, is proposed and experimentally validated.
Business models to offer customized output in electronic commerce
2003
Seller-driven business models (e.g. online bookstores) have been successfully implemented and concretized in Electronic Commerce both in practice and science in the last years. In contrast to this we can depict that more customer-driven business models are implemented in the beginning. One major problem of customizable products and services in Electronic Commerce can be found in the adaptation of the human advisory activity which is inevitable in the traditional sale. For this reason we depict the customization in the customer's view and the corresponding business models in electronic markets. Main focus will be on the improvement of the communication interface between customer and seller i…
Business Process-oriented design of Enterprise Resource Planning (ERP) systems for small and medium enterprises
2006
In the last few years, many organizations have used business process modelling as an effective tool for managing organizational changes. However, process modelling has rarely been exploited for supporting the entire business process management life cycle. This includes the design of business processes as well as their implementation and control. The adoption and implementation of Enterprise Resource Planning (ERP) systems is a crucial issue if referred to small and medium-sized enterprises. The main problem is that the cost of implementation of ERP, intended as the process of customization of the ERP system towards the actual enterprise business processes, overtakes the cost of ERP acquisit…
Coordination policies to support decision making in distributed production planning
2003
Abstract Distributed production networks are considered organizational structures able to match agility and efficiency necessary to compete in the global market. Performances of such organization structures heavily depend on the ability of the network actors of coordinating their activities. The research proposes to model and design coordination problems within production network by using the Multiple Agent Technology. In particular, the paper proposes new strategies for coordinating production-planning activities within production networks. Such models have been developed and tested by using a proper simulation environment developed by using open source code and architecture. The results o…
Analysis, Modeling and Simulation of Complex Regional Clusters Activities, Using Arena Simulation Software
2014
Process modelling is the concise description of the total variation in one quantity, y, by partitioning it into a deterministic component given by a mathematical function of one or more other quantities, x1, x2... plus a random component that follows a particular probability distribution. The models are material or immaterial systems, which represent other systems, so that it may be possible to manipulate the built structures and their states. The main elements of a simulation are: attributes (describe and differentiate entities), variables (system characteristics), resources (whose capacity can be variable), tails (seen in case of unavailability of resources) and statistical accumulators (…
Monte Carlo simulation for the response analysis of long-span suspended cables under wind loads
2004
This paper presents a time-domain approach for analyzing nonlinear random vibrations of long-span suspended cables under transversal wind. A consistent continuous model of the cable, fully accounting for geometrical nonlinearities inherent in cable behavior, is adopted. The effects of spatial correlation are properly included by modeling wind velocity fluctuation as a random function of time and of a single spatial variable ranging over cable span, namely as a one-variate bi-dimensional (1V-2D) random field. Within the context of a Galerkin`s discretization of the equations governing cable motion, a very efficient Monte Carlo-based technique for second-order analysis of the response is prop…
Rear-view mirror use, driver alertness and road type: An empirical study using EEG measures
2006
Abstract The use of rear-view mirrors has been suggested as a good behavioural indicator of driver alertness in traffic situations (Brookhuis, K. A., De Vries, G., & De Waard, D. (1991). The effects of mobile telephoning on driving performance. Accident Analysis and Prevention, 23 (4), 309–316). In general terms, drivers look in the mirrors to find information and adapt their driving to traffic variations. This paper aims to analyse the links between time variations in alertness—measured from EEG activity data—and the frequency of rear-view mirror use in a group of drivers, both on motorways and conventional roads. The results point to a direct relationship between alertness level and mirro…
Increasing the accuracy of untaught robot positions by means of a multi-camera system
2010
We aim to improve the absolute in line positional accuracy of a robot-guided effector to better than 1 mm. We do so using photogrammetric techniques and by relying heavily on simulations to fine tune each parameter and avoid weak configurations. We also use simulations to design an LED calibration object adapted to this application. A test procedure enables us to validate both the simulated results as well as the calibration procedure. The test results exceed expectations by improving the absolute positioning of a robot effector by a factor of 20.
Off-line path correction of robotic face milling using static tool force and robot stiffness
2015
In this paper the developed method for off-line compensation of tool deflections when milling aluminum with an industrial robot is presented. The efficiency of this approach is verified with high precision measurements of deflections using a laser tracker. The compensation method includes both the static milling process model which can predict the mean value components of the tool forces and a new combined local/global approach for estimating the combined stiffnesses of joints. With a process model such as the one presented in this paper and estimates of the robot's joint stiffness values, the tool path can be adjusted to counteract deflections of the tool during milling operations. The mod…
Exploring the uncertainty in capacity estimation at roundabouts
2017
Abstract Purpose In gap-acceptance theory the critical and the follow-up headways have a significant role in determining roundabout entry capacities which in turn depend on circulating flow rates under a specified arrival headway distribution. Calculation considers single mean values of the gap-acceptance parameters, neglecting the inherent variations in these random variables and providing a single value of entry capacity. The purpose of this paper is to derive the entry capacity distribution which accounts for the variations of the contributing (random) variables and suggest how to consider this issue in the operational analysis of the roundabouts. Methods We performed a Monte Carlo simul…