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51.
The available automated CAPP solutions are mostly academic research or specific applications, which cannot be used in different environments. This paper presents a solution for automated process planning for parametric parts included in one CAPP environment with many other software components. It meets the planning requirements of any parts and products in a real industrial environment. This paper provides a brief overview of CAPP and a definition of the parametric parts used. The requirements of the CAPP environment are discussed and its concept and design characteristics are presented. A practical application of the CAPP environment is described in order to validate the proposed solution. 相似文献
52.
Reinaldo Barros Geraldo Plínio Cunha Sathler André Luiz Louren?o Max Seidy Saito Lucio M. Cabral Pabulo Henrique Rampelotto Helena Carla Castro 《International journal of molecular sciences》2014,15(10):17901-17919
Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present in blood. In this work, we review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and their potential as a target for designing new antithrombotic agents. The option of new biotechnological sources is also explored. 相似文献
53.
Gabriel Henrique Horta de Oliveira Paulo Cesar Corrêa Emílio de Souza Santos Pedro Casanova Treto Mayra Darliane Martins Silva Diniz 《International Journal of Food Science & Technology》2011,46(10):2077-2084
The desorption isotherms and thermodynamic properties of cocoa beans were obtained during the drying process of this product. The isotherms were determined by dynamic method for various temperature (25, 35, 45 and 55 °C) and relative humidity (RH) conditions (30, 40, 50, 60, 70 and 80%). Equilibrium moisture content data were correlated by the Guggenheim–Anderson–de Boer (GAB) model, which presented good fit to the data, according to statistical procedures. Equilibrium moisture content ranged from 5.90 to 16.67 d.b.; it increased with an increment in the RH and decreased with increased temperature at a constant RH. Enthalpy values for each model coefficient were encountered, ranging from ?90.05 to 545.96 kJ kg?1. The integral isosteric heat of desorption and differential entropy increased with decreased equilibrium moisture content, a tendency also found for Gibbs free energy. 相似文献
54.
Eduardo Gomes Salgado Carlos Eduardo Sanches da Silva Carlos Henrique Pereira Mello Monique Samaan 《Engineering Management Journal; EMJ》2017,29(3):140-153
The development of new products has become increasingly critical for the competitiveness of companies, due to increased diversity and variety of products, the reduction of product life cycles, and, primarily, globalization of markets. Thus, the identification and prioritization of critical success factors for developing new products is important, particularly for the high degree of risk and uncertainty involved. The main objective of this article is the identification and prioritization of critical success factors in new product development projects in biotechnology companies in the state of Minas Gerais, Brazil. The research method used was a survey questionnaire, which was sent to a sample of 31 biotechnology companies in Minas Gerais state. The principal findings of this research are that interpersonal skills/relationships of the project leader and technical skills are the most critical factors for successful new product development in this industry. The implications for the biotechnology industry in general, as well as for those responsible for managing new product development, are discussed. 相似文献
55.
Ive Hermans Joaquim Henrique Teles Richard Dehn Till-Christian Brüggemann Robert Send Philipp Nikolaus Plessow 《Topics in Catalysis》2014,57(14-16):1256-1264
In this contribution we use computational tools to investigate the reaction of alcohol substrates with reactive nitrogen oxide species such as N2O3 and N2O4, leading to the formation of alkyl nitrites. These nitrites are interesting intermediates which can be processed to various valuable chemicals such as ketones/aldehydes and dimethyl oxalate while regenerating NO x . As such, NO x is used as an oxidation mediator, converting alcohol substrates to more reactive nitrites which can be selectively converted to more desired compounds, closing a catalytic cycle in NO x species. 相似文献
56.
Carlos Henrique Marchi Fernando Laroca António Fábio Carvalho da Silva José Nivaldo Hinckel 《Numerical Heat Transfer, Part A: Applications》2013,63(7):699-717
A one-dimensional mathematical model is presented for flows in a rocket engine that has a regenerative cooling system. The problem involves the flow of a gas in a converging- diverging nozzle, the flow of a coolant in channels distributed around the engine, and the heat conduction through a wall between the gas and the coolant. The numerical model adopted is based on the finite-volume method with a second-order scheme. It was noted that it is important to use variable properties in order to predict the maximum wall temperature in the rocket engine and the drop in pressure of the coolant as it moves along the channels, whereas the thrust of the engine can be calculated with constant properties. 相似文献
57.
58.
Eduardo Gomes Salgado Luiz Alberto Beijo Paulo Sampaio Carlos Henrique Pereira Mello Pedro Saraiva 《国际生产研究杂志》2016,54(18):5416-5433
The ISO 9001 standard is considered as an effective tool to support a quality management system (QMS). A steady growth in the number of ISO 9001 issued certificates is observed worldwide, confirming the interest of companies in this approach. However, information regarding this behaviour over time in the American Continent is scarce. This paper presents a set of qualitative and quantitative analyses related to the ISO 9001 certification (globally and at the country level of the Americas), the use of this standard in countries that were part of the ISO Survey 2011 and modelling the ISO 9001 certification for American countries, in order to characterise through mathematical models, the evolution of the certification process and to identify factors that influence the ISO 9001 issued certificates in the various countries analysed. Based on the work developed, a positive relationship was found between the number of issued certificates in each country per 1000 inhabitants and the indicators of economic development (Gross National Income Per Capita). It is determined that the total reserves of a country is an economic variable that directly affects the number of issued certificates, a finding not observed in other forecasting models. 相似文献
59.
60.
Orlando Soares Henrique Gonçalves António Martins Adriano Carvalho 《Renewable Energy》2010,35(8):1662-1670
This paper describes the models of a wind power system, such as the turbine, generator, power electronics converters and controllers, with the aim to control the generation of wind power in order to maximize the generated power with the lowest possible impact in the grid voltage and frequency during normal operation and under the occurrence of faults. The presented work considers a wind power system equipped with the doubly-fed induction generator and a vector-controlled converter connected between the rotor and the grid. The paper presents comparative results between proportional-integral controllers and neural networks based controllers, showing that better dynamic characteristics can be obtained using neural networks based controllers. 相似文献