Search results for "SIMULATION"
showing 10 items of 5095 documents
Application and assessment of IDEF3‐process flow description capture method
1995
The IDEF techniques have been developed in projects sponsored by the US Air Force in order to describe, specify and model manufacturing systems in a structured graphical form. These techniques can be classified in two categories: the “modelling” and the “descriptive” varieties. Compares two IDEF methods (one of the modelling type and one of the descriptive type) in order to represent (model or describe) two different aspects of an industrial organization. The methods compared are IDEF0, function modelling method, and IDEF3, process flow description capture method. Concludes that when considering the sequencing of the activities in process, aiming at highlighting their eventual simultaneity,…
Sensitivity analysis of efficiency and Malmquist productivity indices: An application to Spanish savings banks
2008
Hypothesis testing and statistical precision in the context of non-parametric efficiency and productivity measurement have been investigated since the early 1990s. Recent contributions focus on this matter through the use of resampling methods-i.e., bootstrapping techniques. However, empirical evidence is still practically non-existent. This gap is more noticeable in the case of banking efficiency studies, where the literature is immense. In this work, we explore productivity growth and productive efficiency for Spanish savings banks over the (initial) post-deregulation period 1992-1998 using Data Envelopment Analysis (DEA) and bootstrapping techniques. Results show that productivity growth…
Improving the Manufacturing Accuracy of the Profiling Machines
2010
Abstract This paper presents the results of theoretical and experimental researches carried out with regard to the optimization of the dynamic behavior of a CNC laser cutting machine, in terms of cutting precision, for the case of flat metallic parts whose contours comprise right angles and which a profiling machine has to process continuously, without stopping in the corner points. It is aimed especially at detailing the influence of the numerical control equipment's setup on the size of the contouring errors and on the smoothness of the movement, factors that have a direct influence on the accuracy and that have been less addressed until now. The theoretical researches indicate that it is…
Comparing three experiential learning methods and their effect on medical students' attitudes to learning communication skills.
2012
Background: Despite numerous studies exploring medical students’ attitudes to communication skills learning (CSL), there are apparently no studies comparing different experiential learning methods and their influence on students’ attitudes. Aims: We compared medical students’ attitudes to learning communication skills before and after a communication course in the data as a whole, by gender and when divided into three groups using different methods. Method: Second-year medical students (n ¼ 129) were randomly assigned to three groups. In group A (n ¼ 42) the theatre in education method, in group B (n ¼ 44) simulated patients and in group C (n ¼ 43) role-play were used. The data were gathere…
On the dynamics of eco-efficiency performance in the European Union
2016
This paper evaluates the evolution of environmental performance in the context of the European Union (EU), over the period 1993–2010. The context is particularly relevant, due to the traditionally high concerns of the EU about these issues, which has triggered off several initiatives and regulations on environmental protection. In this setting, we conduct a two-stage analysis which develops environmental performance indicators in the first stage for each pair country-year, and evaluates its evolution in the second. More specifically, in the first stage we estimate specific efficiencies for three air-pollutants (CO2e, SO2, NOx), along with an eco-efficiency indicator, for which we use the sl…
Cytotoxicity and antimitotic activity of Rhinella schneideri and Rhinella marina venoms.
2019
Abstract Ethnopharmacological relevance Rhinella schneideri and Rhinella marina are toad venoms distributed in different parts of the world, including Brazil, Columbia and amazon. Venoms extracted from different species have many clinical applications such as antimicrobial cardiotonics and treatment of cancer. Aim of the study; In this study, we aim to investigate the effect of venoms extracted from R. schneideri and R. marina on cancer cells and verify possible mechanism of action. Material and method Cytotoxicity analyses was performed using the resazurin reduction assay, where different concentrations of venoms were tested against sensitive CCRF-CEM and P-gp overexpressing ADR/CEM5000 le…
Molecular mechanisms of rosmarinic acid from Salvia miltiorrhiza in acute lymphoblastic leukemia cells
2015
Abstract Ethnopharmacological relevance Rosmarinic acid (RA), a major hydrosoluble bioactive compound found in the Chinese medicinal herb, Salvia miltiorrhiza Bunge, which has been used in traditional Chinese medicine to treat various diseases, including cancer. However, the mechanisms have not been fully elucidated. Aim of the study Guided by microarray hybridization and Ingenuity Pathway Analysis, we identified modes of action of rosmarinic acid (RA) isolated from S. miltiorrhiza on acute lymphoblastic leukemia cells. Materials and methods Microarray data were verified by independent methods: Real-time RT-PCR (mRNA expression), resazurin assay (cytotoxicity of RA towards parental CCRF-CEM…
Approaches to evaluate the virtual instrumentation measurement uncertainties
2002
This paper deals with the metrological characterization of virtual instruments. After a brief description of the features, the components and the working principle of the virtual instruments and the various uncertainty sources are analyzed. Then, two methods to evaluate the uncertainty of the measurement results are presented: a numerical method simulating the physical process of the A/D conversion, and an approximated theoretical method applying the "uncertainty propagation law" of the "guide to the expression of uncertainty in measurement." With both methods, the combined standard uncertainty of the measurement result is obtained, starting from the standard uncertainty generated by each s…
Measurement uncertainty estimation of a virtual instrument
2002
The law of uncertainty propagation is applied to a PC-based virtual instrument. According to the "guide to the expression of uncertainty in measurement", the measuring model and the various sources of uncertainty have been taken into account. The expressions of the combined output uncertainty in various basic digital signal processing blocks, are obtained starting from each input sample absolute accuracy, without taking into account the parameters which regard the overall behavior of an acquisition board, such as the effective number of bits. In order to verify this procedure, the results obtained by means of the theoretical analysis, are compared with the ones obtained from numerical simul…
Assessment of virtual instruments measurement uncertainty
2001
Abstract In this paper, two methods to evaluate the measurement uncertainty of a virtual instrument are presented: a numerical method simulating the physical process of the A/D conversion, and an approximated theoretical method applying the “uncertainty propagation law” of the “guide to the expression of uncertainty in measurement”. After a brief description of the features, the constitution and the working principle of the virtual instruments, the various uncertainty sources, are analyzed. With both methods, the combined standard uncertainty of the measurement result is obtained, starting from the standard uncertainty generated by each single source and without taking into account the para…