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The aim of this study is to describe and analyze the competitive and innovation dynamics of computer equipment and semiconductor industries. Hence, it focuses on analyzing how the technological paradigm characterized by modularity configures itself as the major element in the creation of leading technology platforms, which determine the competitive and innovation dynamics in these industries. With regard to the computer equipment industry, it was concluded that the establishment of technology cooperation, the scale effects, and innovation readiness are the main sources of competitive asymmetry. It was also observed that innovation dynamics in this sector is based on modular designs in the semiconductor industry. On the other hand, their technology advances are due to the evolution of (i) the capacity to increase the number of transistors available in a single circuit and (ii) the capacity of creating design standards able to integrate more circuits in a single chip.

Souza-Correa J.A.,Centro Universitario Salesiano Of Sao Paulo Unisal | Oliveira C.,CTBE - Brazilian Bioethanol Science and Technology Laboratory | Nascimento V.M.,CTBE - Brazilian Bioethanol Science and Technology Laboratory | Wolf L.D.,CTBE - Brazilian Bioethanol Science and Technology Laboratory | And 3 more authors.
Applied Biochemistry and Biotechnology | Year: 2014

Atmospheric pressure O2 plasma was used to produce ozone in order to treat sugarcane bagasse as a function of particle sizes. The fixed bagasse moisture content was 50 %. The delignification efficiency had small improvement due to ozonation process as a function of particle size, varying from 75 up to 80 %. Few amounts of hemicellulose were removed, but the ozonation has not been affected significantly with particle size variance as well (from 30 up to 35 %). The cellulose presented some losses below 1.0 mm size (8-15 %) which was an unexpected result. The conversion of cellulose content into free sugar has shown a significant increase as the particle size has diminished as well. The best condition of the bagasse particle size was for 0.08 mm. For this case, a great quantity of cellulose (78.8 %) was converted into glucose. Optical absorption spectroscopy was applied to determine ozone concentrations in real time where the samples with typical bagasse particle sizes equal or below to 0.5 mm had shown a better absorption of ozone in comparison with greater particle size samples. © 2013 Springer Science+Business Media.

Ridenti M.A.,University of Campinas | Ridenti M.A.,CTBE - Brazilian Bioethanol Science and Technology Laboratory | Souza-Correa J.A.,Centro Universitario Salesiano Of Sao Paulo Unisal | Amorim J.,University of Campinas | Amorim J.,Brazilian Technological Institute of Aeronautics
Journal of Physics D: Applied Physics | Year: 2014

A surface wave discharge (SWD) in argon at atmospheric pressure generated by a surfatron device was studied by optical emission spectroscopy (OES). Two distinct situations were investigated; (i) a discharge plasma in open air and (ii) a discharge plasma totally confined in a quartz tube. The electron density ne, electron temperature Te and gas temperature T g were investigated as a function of applied power and gas flow rate. The self-absorbing method was used to estimate the population of the metastable state Ar(1s5). These physical quantities were determined through optical measurements along the plasma axis of symmetry. The profile of the electron density presented a maximum value under certain conditions, in contrast with typical electron density profiles of SWDs which are usually monotonically decreasing. A correlation between the electron density and the metastable state Ar(1s5) was found in one of these cases, suggesting that stepwise ionization from metastable states and non-local kinetics play an important role on the unexpected increase in ionization degree along the discharge. © 2014 IOP Publishing Ltd.

Crespo Y.A.,Amazonian State University | Naranjo R.A.,Amazonian State University | Burgos J.C.V.,Amazonian State University | Sanchez C.G.,University of Campinas | Sanchez E.M.S.,Centro Universitario Salesiano Of Sao Paulo Unisal
Wood and Fiber Science | Year: 2015

Thermogravimetric analysis was used to study the thermal behavior of Acacia mangium wood under inert atmosphere at heating rates ranging from 5 to 15°C min-1, from room temperature to 800°C. Weight losses of A. mangium wood in inert atmosphere were found to occur in three stages. These three states are generally associated with the decomposition of the three main components of the lignocellulosic materials. Most decomposition occurred in the range of 300-400°C (80% weight approximately). The kinetic parameters of the process were evaluated using the independent parallel reaction model, attributed to the three main components of lignocellulosic materials: hemicelluloses, cellulose, and lignin. The values of activation energy, preexponential factor, and contribution factor were similar to those reported in other studies for this type of biomass. The model proposed predicted an acceptable correlation between the experimental and the calculated curve to the decomposition of A. mangium, with an error of less than 3% of deviation in the temperature range studied. © 2015 by the Society of Wood Science and Technology.

Meneghetti C.R.,Centro Universitario Salesiano Of Sao Paulo Unisal | Tizzei A.,Centro Universitario Salesiano Of Sao Paulo Unisal | Cappelli N.L.,University of Campinas | Umezu C.K.,University of Campinas | Bezzon G.,Centro Universitario Salesiano Of Sao Paulo Unisal
Revista Ciencia Agronomica | Year: 2013

Studies of control strategies for refrigeration systems observe, among other variables, the dynamic behavior of temperature and the consumption of electrical energy. Aiming to contribute to these studies, this work presents the proposal and validation of a mathematical model for the cooling system of a cold-storage unit. The model approximates the dynamics and interdependence of the variables, to first-order systems with time delay and the summation of effects. The input variables available are the frequency of compressor activation and the thermal load imposed on the unit, and as output variables, the air temperature both at the evaporator inlet and at the centre of the chamber, as well as the electrical power consumed by the compressor. The results obtained were satisfactory, with an error of less than 0.11° C for the air temperature at the evaporator inlet, of less than 0.09° C for the temperature at the centre of the chamber, and of less than 1% for the electrical energy consumed.

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