Search results for " Manufacturing"
showing 10 items of 2018 documents
OntoSTEP: Enriching product model data using ontologies
2012
The representation and management of product lifecycle information is critical to any manufacturing organization. Different modeling languages are used at different lifecycle stages, for example STEP's EXPRESS may be used at a detailed design stage, while UML may be used for initial design stages. It is necessary to consolidate product information created using these different languages to build a coherent knowledge base. In this paper, we present an approach to enable the translation of STEP schema and its instances to Ontology Web Language (OWL). This gives a model-which we call OntoSTEP-that can easily be integrated with any OWL ontologies to create a semantically rich model. As an examp…
A beam search algorithm for minimizing crane times in premarshalling problems
2022
The premarshalling problem consists of sorting the containers placed in a bay of the container yard so that they can be retrieved in the order in which they will be required. We study the premarshalling problem with crane time minimization objective and develop a beam search algorithm, with some new elements adapted to the characteristics of the problem, to solve it. We propose various evaluation criteria, depending on the type of container movement, for its local evaluation; a new heuristic algorithm including local search for blue its global evaluation; and several new dominance rules. The computational study shows the contribution of each new element. The performance of the complete algo…
A Model for Assessing the Magnitude and Distribution of Sheath Currents in Medium and High-Voltage Cable Lines
2020
In this article, the authors discuss a simulation model to study the effect of cross-bonding of metallic sheaths, and/or nonmagnetic armors, of single-core medium- and high-voltage cables in the same circuit. In single-core cables, the resistive losses due to the induced circulating currents in cable sheaths or armors cause an increase of the cable temperature, which therefore reduces its ampacity. This is a serious issue affecting the distribution and transmission lines. In addition, the risk of electric shock due to induced voltages may be present if a person is in contact with the armor/sheath at its unbounded end. For these reasons, special bonding techniques of metal sheaths are employ…
Growing Like Germany: Local Public Debt, Local Banks, Low Private Investment
2021
The paper uses a panel of more than 1m German firms over 2010-2016, to provide the first firm-bank level evidence of local crowding out for a developed economy characterized by low interest rates and fiscal austerity. Our mechanism relies on two structural features of Germany's banking landscape: the local segmentation of credit markets for small and medium-sized firms (SME) and the role of local public banks in local public finance. Local public banks dominate lending to small and medium firms in Germany and also have an explicit mandate to lend to the local public sector. With spreads on local government debt at all-time lows, local public banks tried to break even, using their market pow…
Environmental values and customer-perceived value in industrial supplier relationships
2017
This study addresses a gap in the research on supply channel management by integrating environmental values and value creation in the context of buyer-supplier relationships. This study has two objectives: (i) to explore the environmental values structure of industrial customers, and (ii) to test the effect of environmental values on overall value perceptions. The effect of customer's environmental values on the supplier's environmental image and customer-perceived value is tested with structural equation modeling using the PLS method. The empirical analysis is based on a global sample of industrial companies that have a high impact on the environment (n = 121). Key findings of this study a…
A data-driven surrogate-assisted evolutionary algorithm applied to a many-objective blast furnace optimization problem
2017
A new data-driven reference vector-guided evolutionary algorithm has been successfully implemented to construct surrogate models for various objectives pertinent to an industrial blast furnace. A total of eight objectives have been modeled using the operational data of the furnace using 12 process variables identified through a principal component analysis and optimized simultaneously. The capability of this algorithm to handle a large number of objectives, which has been lacking earlier, results in a more efficient setting of the operational parameters of the furnace, leading to a precisely optimized hot metal production process. peerReviewed
Energy consumption analysis of robot based SPIF
2013
Part of: Seliger, Günther (Ed.): Innovative solutions : proceedings / 11th Global Conference on Sustainable Manufacturing, Berlin, Germany, 23rd - 25th September, 2013. - Berlin: Universitätsverlag der TU Berlin, 2013. - ISBN 978-3-7983-2609-5 (online). - http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-40276. - pp. 131–136. Production processes, as used for discrete part manufacturing, are responsible for a substantial part of the environmental impact of products, but are still poorly documented in terms of environmental impact. A thorough analysis of the causes affecting the environmental impact in metal forming processes is mandatory. The present study presents an energy consumption anal…
Water leaching of roasted vanadium slag : Desiliconization and precipitation of ammonium vanadate from vanadium solution
2023
This research investigated water leaching of roasted vanadium slag and studied the effects of leaching parameters, such as agitation speed, temperature, liquid-to-solid ratio, and leaching time. Further, solution purification via desiliconization and precipitation of ammonium vanadate were studied using the vanadium solution obtained from the water leaching of roasted vanadium slag. Vanadium solution contains residual silicon (1.67 g/L), which should be removed before ammonium vanadate precipitation. Based on the results, vanadium can be effectively recovered from vanadium slag and a recovery efficiency of 96.9% was obtained under optimal water leaching conditions. During solution purificat…
Deducing the stage-discharge relationship for contracted weirs by the outflow theory of Malcherek
2019
The aim of this paper was the deduction of a new stage-discharge relationship for a contracted weir, having a crest length less than the channel width, by using the Malcherek’s outflow theory. The average outflow velocity over the rectangular contracted weir was expressed in terms of the head over weir, the momentum correction coefficient and the ratio between the crest length and the channel width. This theoretically deduced stage-discharge formula was calibrated by measurements carried out for values of the ratio between the crest length and the channel width ranging from 0.3125 to 0.9375. In particular, a relationship to estimate the momentum correction coefficient for contracted weirs w…
De l'embauche à la démission ou les écueils du travail associatif dans les associations locales de solidarité internationale
2010
A partir d’une pré-enquête réalisée dans deux associations de solidarité internationale impliquée dans le commerce équitable et partant du constat que le turn-over des salariés y est important, nous avons cherché à comprendre pourquoi, après quelques mois, les nouvelles recrues décident de mettre prématurément un terme à leur activité. Nous nous sommes intéressé à la fois aux organisations, aux salariés mais aussi aux bénévoles présents dans ces collectifs afin d’appréhender l’ensemble des interactions qui s’y produisent pour mieux saisir les facteurs et contraintes à la fois structurelles, individuelles ou relationnelles. On montre que, bien souvent, l’associatif est envisagé comme un lieu…