1000 resultados para spreading technology


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Työn tavoitteena oli selvittää puun ja turpeen seospolton vaikutukset tuhkien hyötykäyttökohteiden valintaan laitoksella tehtävien koeajojen ja kustannus- sekä SWOT-analyysien avulla. Lisäksi tavoitteena oli selvittää lainsäädännön vaikutukset tuhkien hyötykäyttöön. Kustannusanalyysissä tarkasteltiin tuhkien hyödyntämisen nykytilan lisäksi rakeistuslaitosinvestointia ja selvitettiin eri hyötykäyttövaihtoehtojen etuja ja haittoja. Lainsäädäntö vaikuttaa oleellisesti tuhkien hyötykäyttöön. Hyötykäyttöä säädellään sekä kansallisella että EU-tasolta tulevalla lainsäädännöllä. Ympäristölainsäädännön ja etenkin jätelainsäädännön kokonaisuudistuksen myötä myös hyötykäyttöä koskevat lainsäädäntö uudistui. Energiantuotannon tuhkat tulivat jäteverolain piiriin ja lannoiteasetuksenuudistuksella pyrittiin helpottamaan tuhkien lannoitekäyttöä. Myös jäteluokittelu ja sen päättyminen tuhkien osalta vaikuttaa olennaisesti tuhkien käsittelymenetelmien ja hyödyntämisen kannattavuuteen. Jäteluokituksen päättyminen voi viedä tuhkat kemikaalilainsäädännön piiriin. Kustannus- ja SWOT-analyysissä selvitettiin tuhkien hyödyntämisen kannalta keskeiset kustannustekijät. Rakeistuslaitosinvestoinnissa huomioitiin erilaiset tuhkien käsittelymäärät ja niiden vaikutukset kustannuksiin ja investoinnin kannattavuuteen. SWOT-analyysin avulla selvitettiin hyödyntämisen vahvuudet, heikkoudet, mahdollisuudet ja uhkatekijät. Polttoainesuhteella ei ollut poissulkevaa vaikutusta tuhkien hyötykäyttövalintaan. Lentotuhkat soveltuivat parhaiten lannoitehyötykäyttöön ja pohjatuhkat maarakennushyötykäyttöön. Rakeistuslaitosinvestointi olisi kannattava etenkin suuremmilla tuhkamäärillä.

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This paper presents a thermal modeling for power management of a new three-dimensional (3-D) thinned dies stacking process. Besides the high concentration of power dissipating sources, which is the direct consequence of the very interesting integration efficiency increase, this new ultra-compact packaging technology can suffer of the poor thermal conductivity (about 700 times smaller than silicon one) of the benzocyclobutene (BCB) used as both adhesive and planarization layers in each level of the stack. Thermal simulation was conducted using three-dimensional (3-D) FEM tool to analyze the specific behaviors in such stacked structure and to optimize the design rules. This study first describes the heat transfer limitation through the vertical path by examining particularly the case of the high dissipating sources under small area. First results of characterization in transient regime by means of dedicated test device mounted in single level structure are presented. For the design optimization, the thermal draining capabilities of a copper grid or full copper plate embedded in the intermediate layer of stacked structure are evaluated as a function of the technological parameters and the physical properties. It is shown an interest for the transverse heat extraction under the buffer devices dissipating most the power and generally localized in the peripheral zone, and for the temperature uniformization, by heat spreading mechanism, in the localized regions where the attachment of the thin die is altered. Finally, all conclusions of this analysis are used for the quantitative projections of the thermal performance of a first demonstrator based on a three-levels stacking structure for space application.

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The focus of the work reported in this thesis was to study and to clarify the effect of polyelectrolyte multilayer surface treatment on inkjet ink spreading, absorption and print quality. Surface sizing with a size press, film press with a pilot scale coater, and spray coating, have been used to surface treat uncoated wood-free, experimental wood-free and pigmentcoated substrates. The role of the deposited cationic (polydiallydimethylammonium chloride, PDADMAC) and anionic (sodium carboxymethyl cellulose, NaCMC) polyelectrolyte layers with and without nanosilica, on liquid absorption and spreading was studied in terms of their interaction with water-based pigmented and dye-based inkjet inks. Contact angle measurements were made in attempt to explain the ink spreading and wetting behavior on the substrate. First, it was noticed that multilayer surface treatment decreased the contact angle of water, giving a hydrophilic character to the surface. The results showed that the number of cationic-anionic polyelectrolyte layers or the order of deposition of the polyelectrolytes had a significant effect on the print quality. This was seen for example as a higher print density on layers with a cationic polyelectrolyte in the outermost layer. The number of layers had an influence on the print quality; the print density increased with increasing number of layers, although the increase was strongly dependent on ink formulation and chemistry. The use of nanosilica clearly affected the rate of absorption of polar liquids, which also was seen as a higher density of the black dye-based print. Slightly unexpected, the use of nanosilica increased the tendency for lateral spreading of both the pigmented and dye-based inks. It was shown that the wetting behavior and wicking of the inks on the polyelectrolyte coatings was strongly affected by the hydrophobicity of the substrate, as well as by the composition or structure of the polyelectrolyte layers. Coating only with a cationic polyelectrolyte was not sufficient to improve dye fixation, but it was demonstrated that a cationic-anionic-complex structure led to good water fastness. A threelayered structure gave the same water fastness values as a five-layered structure. Interestingly, the water fastness values were strongly dependent not only on the formed cation-anion polyelectrolyte complexes but also on the tendency of the coating to dissolve during immersion in water. Results showed that by optimizing the chemistry of the layers, the ink-substrate interaction can be optimized.

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In this paper, we perform a thorough analysis of a spectral phase-encoded time spreading optical code division multiple access (SPECTS-OCDMA) system based on Walsh-Hadamard (W-H) codes aiming not only at finding optimal code-set selections but also at assessing its loss of security due to crosstalk. We prove that an inadequate choice of codes can make the crosstalk between active users to become large enough so as to cause the data from the user of interest to be detected by other user. The proposed algorithm for code optimization targets code sets that produce minimum bit error rate (BER) among all codes for a specific number of simultaneous users. This methodology allows us to find optimal code sets for any OCDMA system, regardless the code family used and the number of active users. This procedure is crucial for circumventing the unexpected lack of security due to crosstalk. We also show that a SPECTS-OCDMA system based on W-H 32(64) fundamentally limits the number of simultaneous users to 4(8) with no security violation due to crosstalk. More importantly, we prove that only a small fraction of the available code sets is actually immune to crosstalk with acceptable BER (<10(-9)) i.e., approximately 0.5% for W-H 32 with four simultaneous users, and about 1 x 10(-4)% for W-H 64 with eight simultaneous users.

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Civil society and sugarcane farmer demands indicate that harvesting technology has enough limitations to jeopardize production in large sugar cane producing areas. This work analyses the current mechanical harvesting compared to a semi-mechanical harvesting proposal, on the bases of eleven characteristics considered determinant for a quick spreading of green cane harvesting on hilly areas, with lower impact on agricultural labor and farmers investment capacity.

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In this paper, we present a fuzzy approach to the Reed-Frost model for epidemic spreading taking into account uncertainties in the diagnostic of the infection. The heterogeneities in the infected group is based on the clinical signals of the individuals (symptoms, laboratorial exams, medical findings, etc.), which are incorporated into the dynamic of the epidemic. The infectivity level is time-varying and the classification of the individuals is performed through fuzzy relations. Simulations considering a real problem with data of the viral epidemic in a children daycare are performed and the results are compared with a stochastic Reed-Frost generalization

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There are several tools in the literature that support innovation in organizations. Some of the most cited are the so-called technology roadmapping methods, also known as TRM. However, these methods are designed primarily for organizations that adopt the market pull strategy of technology-product integration. Organizations that adopt the technology push integration strategy are neglected in the literature. Furthermore, with the advent of open innovation, it is possible to note the need to consider the adoption of partnerships in the innovation process. Thus, this study proposes a method of technology roadmapping, identified as method for technology push (MTP), applicable to organizations that adopt the technology push integration strategy, such as SMEs and independent research centers in an open-innovation environment. The method was developed through action-research and was assessed from two analytical standpoints: externally, via a specific literature review on its theoretical contributions, and internally, through the analysis of potential users` perceptions on the feasibility of applying MTP. The results indicate both the unique character of the method and its perceived implementation feasibility. Future research is suggested in order to validate the method in different types of organizations (C) 2011 Elsevier Ltd. All rights reserved.

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Many authors point out that the front-end of new product development (NPD) is a critical success factor in the NPD process and that numerous companies face difficulties in carrying it out appropriately. Therefore, it is important to develop new theories and proposals that support the effective implementation of this earliest phase of NPD. This paper presents a new method to support the development of front-end activities based on integrating technology roadmapping (TRM) and project portfolio management (PPM). This new method, called the ITP Method, was implemented at a small Brazilian high-tech company in the nanotechnology industry to explore the integration proposal. The case study demonstrated that the ITP Method provides a systematic procedure for the fuzzy front-end and integrates innovation perspectives into a single roadmap, which allows for a better alignment of business efforts and communication of product innovation goals. Furthermore, the results indicated that the method may also improve quality, functional integration and strategy alignment. (C) 2010 Elsevier Inc. All rights reserved.

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This paper presents a proposal for a Quality Management System for a generic GNSS Surveying Company as an alternative for management and service quality improvements. As a result of the increased demand for GNSS measurements, a large number of new or restructured companies were established to operate in that market. Considering that GNSS surveying is a new process, some changes must be performed in order to accommodate the old surveying techniques and the old fashioned management to the new reality. This requires a new management model that must be based on a well-described procedure sequence aiming at the Total Management Quality for the company. The proposed Quality Management System was based on the requirements of the Quality System ISO 9000:2000, applied to the whole company, focusing on the productive process of GNSS surveying work.

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Considering the increasing popularity of network-based control systems and the huge adoption of IP networks (such as the Internet), this paper studies the influence of network quality of service (QoS) parameters over quality of control parameters. An example of a control loop is implemented using two LonWorks networks (CEA-709.1) interconnected by an emulated IP network, in which important QoS parameters such as delay and delay jitter can be completely controlled. Mathematical definitions are provided according to the literature, and the results of the network-based control loop experiment are presented and discussed.

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This work presents a case study on technology assessment for power quality improvement devices. A system compatibility test protocol for power quality mitigation devices was developed in order to evaluate the functionality of three-phase voltage restoration devices. In order to validate this test protocol, the micro-DVR, a reduced power development platform for DVR (dynamic voltage restorer) devices, was tested and the results are discussed based on voltage disturbances standards. (C) 2011 Elsevier B.V. All rights reserved.

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Wetting balance tests of copper sheets submerged in tin solder baths were carried out in a completely automatic wetting balance. Wetting curves were examined for three different values of sheet thickness and four different solder bath temperatures. Most of the wetting curves showed a distorted shape relative to that of a standard curve, preventing calculation of important wetting parameters, such as the wetting rate and the wetting force. The wetting tests showed that the distortion increased for a thicker sheet thickness and a lower solder bath temperature, being the result of solder bath solidification around the submerged sheet substrate. (C) 2008 Elsevier B.V. All rights reserved.

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A green ceramic tape micro-heat exchanger was developed using Low Temperature Co-fired Ceramics technology (LTCC). The device was designed by using Computational Aided Design software and simulations were made using a Computational Fluid Dynamics package (COMSOL Multiphysics) to evaluate the homogeneity of fluid distribution in the microchannels. Four geometries were proposed and simulated in two and three dimensions to show that geometric details directly affect the distribution of velocity in the micro-heat exchanger channels. The simulation results were quite useful for the design of the microfluidic device. The micro-heat exchanger was then constructed using the LTCC technology and is composed of five thermal exchange plates in cross-flow arrangement and two connecting plates, with all plates stacked to form a device with external dimensions of 26 x 26 x 6 mm(3).

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The application of airborne laser scanning (ALS) technologies in forest inventories has shown great potential to improve the efficiency of forest planning activities. Precise estimates, fast assessment and relatively low complexity can explain the good results in terms of efficiency. The evolution of GPS and inertial measurement technologies, as well as the observed lower assessment costs when these technologies are applied to large scale studies, can explain the increasing dissemination of ALS technologies. The observed good quality of results can be expressed by estimates of volumes and basal area with estimated error below the level of 8.4%, depending on the size of sampled area, the quantity of laser pulses per square meter and the number of control plots. This paper analyzes the potential of an ALS assessment to produce certain forest inventory statistics in plantations of cloned Eucalyptus spp with precision equal of superior to conventional methods. The statistics of interest in this case were: volume, basal area, mean height and dominant trees mean height. The ALS flight for data assessment covered two strips of approximately 2 by 20 Km, in which clouds of points were sampled in circular plots with a radius of 13 m. Plots were sampled in different parts of the strips to cover different stand ages. The clouds of points generated by the ALS assessment: overall height mean, standard error, five percentiles (height under which we can find 10%, 30%, 50%,70% and 90% of the ALS points above ground level in the cloud), and density of points above ground level in each percentile were calculated. The ALS statistics were used in regression models to estimate mean diameter, mean height, mean height of dominant trees, basal area and volume. Conventional forest inventory sample plots provided real data. For volume, an exploratory assessment involving different combinations of ALS statistics allowed for the definition of the most promising relationships and fitting tests based on well known forest biometric models. The models based on ALS statistics that produced the best results involved: the 30% percentile to estimate mean diameter (R(2)=0,88 and MQE%=0,0004); the 10% and 90% percentiles to estimate mean height (R(2)=0,94 and MQE%=0,0003); the 90% percentile to estimate dominant height (R(2)=0,96 and MQE%=0,0003); the 10% percentile and mean height of ALS points to estimate basal area (R(2)=0,92 and MQE%=0,0016); and, to estimate volume, age and the 30% and 90% percentiles (R(2)=0,95 MQE%=0,002). Among the tested forest biometric models, the best fits were provided by the modified Schumacher using age and the 90% percentile, modified Clutter using age, mean height of ALS points and the 70% percentile, and modified Buckman using age, mean height of ALS points and the 10% percentile.

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The application of nanoemulsions is due to have good stability, uniform spreading and enhance active penetration upon skin. Nanometer emulsions can be obtained by low-energy emulsification method. The required hydrophilic and lipophilic balance indicates the better balance of emulsifier for optimum system emulsification. Emulsion stability is evidently controlled for the properties of the adsorbed layer formed in the surface of its globules, know as potential zeta. The aim of this work was to evaluate the oil/water nanoemulsion of formulation obtained after 15 years of preparation. The results suggested that the nanoemulsion have performed stability for many years.