801 resultados para Manufactures.
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This paper investigates the application of a non-destructive ultrasonic technique for characterising the rheological properties of solder paste through the use of through-mode microsecond ultrasonic pulses for evaluation of viscoelastic properties of lead-free solder paste containing different types of flux. Ultrasonic techniques offer a robust and reliable form of non-destructive testing of materials where access to the sample is restricted or when sample handling can interfere with the monitoring or analysis process due to externally incorporated changes to the material’s physical state or accidental contamination during the removal or testing process. Ultrasonic based techniques are increasingly used for quality control and production monitoring functions which requires evaluation of changes in material properties for a wide range of industrial applications such as cement paste quality, plastic/polymer extrusion process, dough and even sugar content in beverage drinks. In addition, ultrasound techniques are of great interest for their capability to take rapid measurements in systems which are optically opaque. The conventional industry approach for characterising the rheological properties of suspensions during processing/packaging stage is mainly through the use of viscometer and some through the use of rheometer. One of the potential limitations of viscometer and rheometer based measurements is that the collection and preparation of the solder paste samples can irreversibly alter the structure and flow behaviour of the sample. Hence the measurement may not represent the actual quality of the whole production batch. Secondly, rheological measurements and the interpretation of rheological data is a very technical and time consuming process, which requires professionally trained R&D personnel. The ultrasound technique being proposed provides simple, yet accurate and easy to use solution for the in-situ rheological characterisation of solder pastes which will benefit the materials suppliers (who formulate and produce solder pastes) and solder paste consumers (especially, contract electronics manufacturers). The results from the work show that the technique can be used by R&D personnel involved in paste formulation and manufacture to monitor the batch-to-batch quality and consistency.
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¿Puede un retrato pictórico suscitar un ejercicio de microhistoria? Nuestra investigación tratará de aportar una respuesta positiva a esta cuestión, analizando para ello uno de los pocos retratos del pintor postimpresionista Joaquim Mir Trinxet, fechado en 1926. El protagonista representado no es otro que el suegro del pintor, Antoni Estalella i Trinxet, un insigne personaje de Vilanova y la Geltrú (Barcelona) que vivió entre dos siglos. La obra está ambientada en la tienda de juguetes de la familia, convirtiéndose así en una de las escasas pinturas que han captado el interior de una juguetería en la España anterior a la Guerra Civil. Gracias a los trabajos de archivo realizados, este artículo reúne diversos documentos inéditos que permiten reconstruir no sólo la vida del retratado, que llegó a ser corresponsal de Francisco Pi y Margall, sino también el ambiente social, artístico y comercial de Vilanova, en un período que abarca desde la década de 1870 a la primera mitad del siglo XX, en plena “Edad de Oro” de la industria juguetera. Es esta una propuesta de metodología historiográfica cuyo recorrido comienza en el oficio arcaico de la tonelería para desembocar al fin en los albores del comercio moderno de juguetes.
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The use of the consumer boycott as a political tool is commonly associated with pre-revolutionary colonial America and has been identified by historians as an important means through which American women were politicized. This article argues that from the late seventeenth century, Irish political discourse advocated the non-consumption of imported goods and support for home manufactures by women in ways that were strikingly similar to those used later in North America. In Ireland and, subsequently in the American colonies, the virtuous woman consumer was given an active public role by political and social commentators. Rather than being a “brilliantly original American invention,” as T. H. Breen has argued, the political exploitation of a consumer boycott and the promotion of local industry were among what Bernard Bailyn has described as the “set of ideas, already in scattered ways familiar” to the revolutionary leaders through the Irish experience. The article also argues that a shared colonial environment gave Irish and American women a public patriotic role in the period, c. 1700–1780 that they did not have in the home countries of England and Scotland.
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Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (brown) rice having higher arsenic levels than polished (white). It is reported here that rice bran, both commercially purchased and specifically milled for this study, have levels of inorganic arsenic, a nonthreshold, class 1 carcinogen, reaching concentrations of approximately 1 mg/kg dry weight, around 10-20 fold higher than concentrations found in bulk grain. Although pure rice bran is used as a health food supplement, perhaps of more concern is rice bran solubles, which are marketed as a superfood and as a supplement to malnourished children in international aid programs. Five rice bran solubles products were tested, sourced from the United States and Japan, and were found to have 0.61-1.9 mg/kg inorganic arsenic. Manufactures recommend approximately 20 g servings of the rice bran solubles per day, which equates to a 0.012-0.038 mg intake of inorganic arsenic. There are no maximum concentration levels (MCLs) set for arsenic or its species in food stuffs. EU and U.S. water regulations, set at 0.01 mg/L total or inorganic arsenic, respectively, are based on the assumption that 1 L of water per day is consumed, i.e., 0.01 mg of arsenic/ day. At the manufacturers recommended rice bran solubles consumption rate, inorganic arsenic intake exceeds 0.01 mg/ day, remembering that rice bran solubles are targeted at malnourished children and that actual risk is based on mg kg(-1) day(-1) intake.
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Semiconductor manufactures are increasing reliant on optical emission spectroscopy (OES) to source information on plasma characteristics and process change. However, nonlinearities in the response of OES sensors and errors in their calibration lead to discrepancies in observed wavelength detector response. This paper presents a technique for the retrospective spectral calibration of multiple OES sensors. Underlying methodology is given, and alignment performance is evaluated using OES recordings from a semiconductor plasma process. The paper concludes with a discussion of results and suggests avenues for future work.
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This document contains a memorial, which was written by the citizens of Fairfield district of South Carolina, with a purpose of securing their constitutional right of expressing formal sentiments in regard to excluding tariff on woolen manufactures. It was presented to the president and members of the Senate, and to the speaker and members of the House of Representatives in Congress.
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Electrónica e Telecomunicações
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Relatório de Estágio Apresentado ao Instituto de Contabilidade e Administração do Porto para a obtenção do grau de Mestre em Empreendedorismo e Internacionalização, sob orientação da Mestre Inês Veiga Pereira
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This Thesis has the main target to make a research about FPAA/dpASPs devices and technologies applied to control systems. These devices provide easy way to emulate analog circuits that can be reconfigurable by programming tools from manufactures and in case of dpASPs are able to be dynamically reconfigurable on the fly. It is described different kinds of technologies commercially available and also academic projects from researcher groups. These technologies are very recent and are in ramp up development to achieve a level of flexibility and integration to penetrate more easily the market. As occurs with CPLD/FPGAs, the FPAA/dpASPs technologies have the target to increase the productivity, reducing the development time and make easier future hardware reconfigurations reducing the costs. FPAA/dpAsps still have some limitations comparing with the classic analog circuits due to lower working frequencies and emulation of complex circuits that require more components inside the integrated circuit. However, they have great advantages in sensor signal condition, filter circuits and control systems. This thesis focuses practical implementations of these technologies to control system PID controllers. The result of the experiments confirms the efficacy of FPAA/dpASPs on signal condition and control systems.
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Welle Laser is a Brazilian company that manufactures marking and engraving machines mainly for large-scale industry segments providing solutions that help increase productivity. Welle laser has 60% market share in Brazil and decided to go internationally in 2015, mainly to increase revenues and diversify business risks. Welle opened an office in Switzerland and celebrated a contract with a Mexican company to distribute their machines in Mexico. The next step for Welle is expanding its operation to USA. In my project I accessed the viability and reasons to enter the US market, the region where Welle should start its operation, and the best entry mode strategy.
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1906.
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