Examinando por Materia "Design parameters"

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    Assembly sequences definition through hierarchical subassembly approach
    (DELFT UNIV TECHNOLOGY, FAC INDUST DESIGN ENG, 2010-01-01) Gómez, G.O.; Viganò, R.
    Design processes are leading to the reduction of product development time and costs. This trend applies to the evaluation of function, architecture and high level information as far as possible at early stages of product design in order to allow the designer to compare radically different solutions rather than proceeding with fine tuning of a single option. Specifically, design of assembly processes requires information regarding neighborhood, interfaces and interactions between product components from product architecture definition stage, difficult to reach at early stages of design. Besides, assembly process concerns human interaction which is considered in a subjective way when it is analyzed as a design parameter, enterprise-specific conditions, and many suppositions derived from queries of skilled staff. So, an automated tool working with general abstract information available at early stages of design could be able to present more realistic behavior against methodologies with specific hypotheses and rules. In this work an automated method to find feasible assembly sequences without human intervention, in contrast with several solutions presented by different authors, is proposed. The developed method starts with the acquisition and evaluation of topological information of interaction between components of a discrete mechanical product at the early stages of concept and embodiment design [16], followed by the identification and hierarchical classification of independent minimum level subassemblies until the completion of the assembly procedure of the system obtaining at least one feasible assembly sequence. In this way an automated tool which yields a finite discrete number of feasible assembly sequences from all possible assembly solutions, is presented. © Organizing Committee of TMCE 2010 Symposium.
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    Two-dimensional description of absorption in humans after dermal exposure to volatile organic compounds
    (TAYLOR & FRANCIS INC, 2017-06-03) Simon, Laurent; Ospina, Juan; Simon, Laurent; Ospina, Juan; Universidad EAFIT. Departamento de Ciencias; Lógica y Computación
    A two-dimensional diffusion model was developed to predict the absorption of chemicals in humans following dermal contact. A firstorder evaporation rate equation was applied to the skin surface while a perfect-sink boundary condition was imposed at the stratum corneum/viable epidermis interface. Initially, there was a certain amount of the substance present within the stratum corneum at the end of the exposure period. Laplace transform techniques were implemented to solve the governing equations and to derive an expression for the time elapsed before reaching 90% of the final amount of chemical absorbed by the body. This index was 0.43, 2.67, 6.91, and 36.9 h for ethanol, diphenylamine, p-nitroaniline, and benzyl butyl-phthalate, respectively. Simulations show that surface evaporation is important for highly volatile compounds. A large fraction of the amount of poorly volatile compounds, available in the skin after exposure, was absorbed into the bloodstream. © Taylor & Francis Group, LLC.