scholarly journals EXPERIMENTAL VALIDATION OF AN ESCALATOR SIMULATION MODEL

2019 ◽  
Vol 49 (3) ◽  
pp. 187-192
Author(s):  
Juan David CANO-MORENO ◽  
José María CABANELLAS BECERRA

Today’s escalator mechanical systems are based on 100-year-old conventional designs. A sustainable innovation is possible but the industrial inertia of making a prototype for each design has to be changed. This document describes a methodological approach for comparing and validating simulation models through measurements performed on a prototype of a recently patented design. The methodology is based in the adjustment of parameters and the synchronization of cyclic signals in time, allowing the comparison of measurements and simulated outputs. Results shows a high level of correlation between the signals in the time and frequency domains, thus validating the dynamic model and the methodology here presented.

Author(s):  
Zhimin Xi ◽  
Hao Pan ◽  
Ren-Jye Yang

Reliability analysis based on the simulation model could be wrong if the simulation model were not validated. Various model bias correction approaches have been developed to improve the model credibility by adding the identified model bias to the baseline simulation model. However, little research has been conducted for simulation models with dynamic system responses. This paper presents such a framework for model bias correction of dynamic system responses for reliability analysis by addressing three technical components including: i) a validation metric for dynamic system responses, ii) an effective approach for dynamic model bias calibration and approximation, and iii) reliability analysis considering the dynamic model bias. Two case studies including a thermal problem and a corroded beam problem are employed to demonstrate the proposed approaches for simulation-based reliability analysis.


Author(s):  
Virginia Fani ◽  
Bianca Bindi ◽  
Romeo Bandinelli

HVLV environments are characterized by high product variety and small lot production, pushing companies to recursively design and optimize their production systems in a very short time to reach high-level performance. To increase their competitiveness, companies belonging to these industries, often SMEs working as third parties, ask for decision-making tools to support them in a quick and reactive reconfiguration of their production lines. Traditional discrete event simulation models, widely studied in the literature to solve production-related issues, do not allow real-time support to business decisions in dynamic contexts, due to the time-consuming activities needed to re-align parameters to changing environments. Data-driven approach overcomes these limitations, giving the possibility to easily update input and quickly rebuild the model itself without any changes in the modeling code. The proposed data-driven simulation model has also been interfaced with a commonly-used BI tool to support companies in the iterative comparison of different scenarios to define the optimal resource allocation for the requested production plan. The simulation model has been implemented into a SME operating in the footwear industry, showing how this approach can be used by companies to increase their performance even without a specific knowledge in building and validating simulation models.


2020 ◽  
pp. 89-96
Author(s):  
Victoria Vavilova

Purpose. The aim of the article is to develop a simulation model of internal product flow management processes of pharmacy networks. Methodology of research. The theoretical basis for building a system and dynamic model of flow control in the logistics system of the pharmacy network are scientific articles by domestic and foreign scientists on the problems of management of logistics and flow of pharmaceutical companies and pharmacy networks. The following research methods are used to achieve this goal: analysis and synthesis (in the study of the theoretical foundations of the formation of logistics systems of pharmacy networks); economic and mathematical modelling (to optimize the management of domestic commodity flows). Findings. A simulation system and dynamic model of product flow management of the logistics system of the pharmacy network in conditions of demand uncertainty has been developed, in particular: 1) the input variables and parameters of the commodity flow management model in the logistics system of the pharmacy network are studied, the limitations and conditions of its application are formed; 2) a system of difference equations of levels, rates and auxiliary variables of the model is developed. Originality. Scientific and methodological approach to the management of commodity flows of logistics systems of pharmacy networks in terms of random demand is improved on the basis of a simulation model of system dynamics. It includes a sub-model of commodity flows and a sub-model of accounting for logistics costs, the implementation of which within the mechanism of management of commodity flows of logistics systems of pharmacy networks allows to simplify the process of analysis and management of the pharmacy network management decisions of operational and tactical nature. Practical value. The results of the study can be applied in practical activities of pharmacy networks in order to increase the efficiency of formation and operation of their logistics systems. Key words: commodity flow management, logistics systems of pharmacy networks, optimization, modelling.


2021 ◽  
Vol 13 (9) ◽  
pp. 5004
Author(s):  
Raquel Ferreras-Garcia ◽  
Jordi Sales-Zaguirre ◽  
Enric Serradell-López

There is currently an increasing interest for sustainable innovation in our society. The European agendas highlight the role of higher education institutions in the formation and development of innovation competences among students. Our study aimed to contribute to the analysis of the level of achievement of students’ innovation competences by considering two sustainable development goals (SDG) of the 2030 United Nations’ Agenda: Gender Equality (SDG 5) and Quality Education (SDG 4). This article tries to answer how business students perceive their own innovation competences and which innovative competences are best achieved by students, as well as if there are differences in the achievement of these competences depending on the students’ gender. Our results, from a sample of 360 students in the Business Administration and Management Bachelor’s Degree at the Universitat Oberta de Catalunya, confirm the extensive development of innovation competences. Moreover, female students present a high level of preparation for innovation-oriented action. These findings have educational implications for potentiating the innovation competences and environments where females can attain innovation skills.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bo-yong Park ◽  
Seok-Jun Hong ◽  
Sofie L. Valk ◽  
Casey Paquola ◽  
Oualid Benkarim ◽  
...  

AbstractThe pathophysiology of autism has been suggested to involve a combination of both macroscale connectome miswiring and microcircuit anomalies. Here, we combine connectome-wide manifold learning with biophysical simulation models to understand associations between global network perturbations and microcircuit dysfunctions in autism. We studied neuroimaging and phenotypic data in 47 individuals with autism and 37 typically developing controls obtained from the Autism Brain Imaging Data Exchange initiative. Our analysis establishes significant differences in structural connectome organization in individuals with autism relative to controls, with strong between-group effects in low-level somatosensory regions and moderate effects in high-level association cortices. Computational models reveal that the degree of macroscale anomalies is related to atypical increases of recurrent excitation/inhibition, as well as subcortical inputs into cortical microcircuits, especially in sensory and motor areas. Transcriptomic association analysis based on postmortem datasets identifies genes expressed in cortical and thalamic areas from childhood to young adulthood. Finally, supervised machine learning finds that the macroscale perturbations are associated with symptom severity scores on the Autism Diagnostic Observation Schedule. Together, our analyses suggest that atypical subcortico-cortical interactions are associated with both microcircuit and macroscale connectome differences in autism.


Buildings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 242
Author(s):  
Christoph Schünemann ◽  
David Schiela ◽  
Regine Ortlepp

Can building performance simulation reproduce measured summertime indoor conditions of a multi-residential building in good conformity? This question is answered by calibrating simulated to monitored room temperatures of several rooms of a multi-residential building for an entire summer in two process steps. First, we did a calibration for several days without the residents being present to validate the building physics of the 3D simulation model. Second, the simulations were calibrated for the entire summer period, including the residents’ impact on evolving room temperature and overheating. As a result, a high degree of conformity between simulation and measurement could be achieved for all monitored rooms. The credibility of our results was secured by a detailed sensitivity analysis under varying meteorological conditions, shading situations, and window ventilation or room use in the simulation model. For top floor dwellings, a high overheating intensity was evoked by a combination of insufficient use of night-time window ventilation and non-heat-adapted residential behavior in combination with high solar gains and low heat storage capacities. Finally, the overall findings were merged into a process guideline to describe how a step-by-step calibration of residential building simulation models can be done. This guideline is intended to be a starting point for future discussions about the validity of the simplified boundary conditions which are often used in present-day standard overheating assessment.


2010 ◽  
Vol 26-28 ◽  
pp. 862-869
Author(s):  
Tao Peng ◽  
Zhi Peng Li ◽  
Chang Shu Zhan ◽  
Xiang Luo ◽  
Qian Wang

Through analyzing the process of brake, a dynamic model of automobile and a model of the relationship between braking distance and adhesion coefficient were formed; also a simulation calculating model of braking distance was established with the use of Matlab. Finally, a research was done toward the braking distance of a type of a car running on a road after using snow-melting agent. On one hand, with the application of the simulation model which has been established, calculations have been done to the braking distance of Bora vehicles running on roads after using deicing salt; on the other hand, by experiments, Bora vehicles’ braking distance and maximum braking deceleration under the same road condition were measured, meanwhile, the established simulation model was verified.


2013 ◽  
Vol 309 ◽  
pp. 366-371 ◽  
Author(s):  
František Manlig ◽  
Radek Havlik ◽  
Alena Gottwaldova

This paper deals with research in computer simulation of manufacturing processes. The paper summarizes the procedures associated with developing the model, experimenting with and evaluating the model results. The key area is of experimentation with the simulation model and evaluation using indicators or multi-criteria functions. With regards to the experiment the crucial variables are the simulation model. The key ideas are to set the number of variables, depending on what a given simulation will be. For example, when introducing new technology into production, modify the type of warehouse, saving workers, thus economizing. The simulation models for the operational management uses simplified models, if possible, a minimum number of variables to obtain the result in shortest possible time. These models are more user friendly and the course will be conducted mostly in the background. An example of a criteria function is the number of parts produced or production time. Multi-criteria function has given us the opportunity to make better quality decisions. It is based on the composition of several parameters, including their weight to one end point. The type of evaluation functions, whether it is an indicator or criteria function is selected and based on customer requirements. In most cases it is recommended to use the multi-dimensional function. It gives us a more comprehensive view of the results from the model and facilitates decision-making. The result of this paper is a display of setting parameters for the experimentation on a sample model. Furthermore, the comparisons of results with a multi-criteria objective function and one-criterion indicator.


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