905 resultados para Advanced Encryption Standard


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The application of multivariate calibration techniques to multicomponent analysis by UV-VIS molecular absorption spectrometry is a powerful tool for simultaneous determination of several chemical species. However, when this methodology is accomplished manually, it is slow and laborious, consumes high amounts of reagents and samples, is susceptible to contaminations and presents a high operational cost. To overcome these drawbacks, a flow-batch analyser is proposed in this work. This analyser was developed for automatic preparation of standard calibration and test (or validation) mixtures. It was applied to the simultaneous determination of Cu2+, Mn2+ and Zn2+ in polyvitaminic and polymineral pharmaceutical formulations, using 4-(2-piridilazo) resorcinol as reagent and a UV-VIS spectrophotometer with a photodiode array detector. The results obtained with the proposed system are in good agreement with those obtained by flame atomic absorption spectrometry, which was employed as reference method. With the proposed analyser, the preparation of calibration and test mixtures can be accomplished about four hours, while the manual procedure requires at least two days. Moreover, it consumes smaller amounts of reagents and samples than the manual procedure. After the preparation of calibration and test mixtures, 60 samples h-1 can be carried out with the proposed flow-batch analyser.

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A quantitative analysis is made on the correlation ship of thermodynamic property, i.e., standard enthalpy of formation (ΔH fº) with Kier's molecular connectivity index(¹Xv),vander waal's volume (Vw) electrotopological state index (E) and refractotopological state index (R) in gaseous state of alkanes. The regression analysis reveals a significant linear correlation of standard enthalpy of formation (ΔH fº) with ¹Xv, Vw, E and R. The equations obtained by regression analysis may be used to estimate standard enthalpy of formation (ΔH fº) of alkanes in gaseous state.

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Since the introduction of automatic orbital welding in pipeline application in 1961, significant improvements have been obtained in orbital pipe welding systems. Requirement of more productive welding systems for pipeline application forces manufacturers to innovate new advanced systems and welding processes for orbital welding method. Various methods have been used to make welding process adaptive, such as visual sensing, passive visual sensing, real-time intelligent control, scan welding technique, multi laser vision sensor, thermal scanning, adaptive image processing, neural network model, machine vision, and optical sensing. Numerous studies are reviewed and discussed in this Master’s thesis and based on a wide range of experiments which already have been accomplished by different researches the vision sensor are reported to be the best choice for adaptive orbital pipe welding system. Also, in this study the most welding processes as well as the most pipe variations welded by orbital welding systems mainly for oil and gas pipeline applications are explained. The welding results show that Gas Metal Arc Welding (GMAW) and its variants like Surface Tension Transfer (STT) and modified short circuit are the most preferred processes in the welding of root pass and can be replaced to the Gas Tungsten Arc Welding (GTAW) in many applications. Furthermore, dual-tandem gas metal arc welding technique is currently considered the most efficient method in the welding of fill pass. Orbital GTAW process mostly is applied for applications ranging from single run welding of thin walled stainless tubes to multi run welding of thick walled pipes. Flux cored arc welding process is faster process with higher deposition rate and recently this process is getting more popular in pipe welding applications. Also, combination of gas metal arc welding and Nd:YAG laser has shown acceptable results in girth welding of land pipelines for oil and gas industry. This Master’s thesis can be implemented as a guideline in welding of pipes and tubes to achieve higher quality and efficiency. Also, this research can be used as a base material for future investigations to supplement present finding.

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The offset printing process is complex and involves the meeting of two essentially complex materials, printing ink and paper, upon which the final product is formed. It can therefore be expected that a multitude of chemical and physical interactions and mechanisms take place at the ink-paper interface. Interactions between ink and paper are of interest to both the papermakers and ink producers, as they wish to achieve better quality in the final product. The objective of this work is to clarify the combined influence of paper coating structure, printing ink and fountain solution on ink setting and the problems related to ink setting. A further aim is to identify the mechanisms that influence ink setting problems, and to be able to counteract them by changing properties of the coating layer or by changing the properties of the ink. The work carried out for this thesis included use of many techniques ranging from standard paper and printability tests to advanced optical techniques for detection of ink filaments during ink levelling. Modern imaging methods were applied for assessment of ink filament remain sizes and distribution of ink components inside pigment coating layers. Gravimetric filtration method and assessment of print rub using Ink-Surface-Interaction-Tester (ISIT) were utilized to study the influence of ink properties on ink setting. The chemical interactions were observed with the help of modified thin layer chromatography and contact angle measurements using both conventional and high speed imaging. The results of the papers in this thesis link the press operational parameters to filament sizes and show the influence of these parameters to filament size distribution. The relative importance between the press operation parameters was shown to vary. The size distribution of filaments is important in predicting the ink setting behaviour, which was highlighted by the dynamic gloss and ink setting studies. Prediction of ink setting behaviour was also further improved by use of separate permeability factors for different ink types in connection to filtration equations. The roles of ink components were studied in connection to ink absorption and mechanism of print rub. Total solids content and ratio of linseed oil to mineral oil were found to determine the degree of print rub on coated papers. Wax addition improved print rub resistance, but would not decrease print rub as much as lowering the total solids content in the ink. Linseed oil was shown to absorb into pigment coating pores by mechanism of adsorption to pore walls, which highlights the need for sufficient pore surface area for improved chromatographic separation of ink components. These results should help press operators, suppliers of printing presses, papermakers and suppliers to papermakers, to better understand the material and operating conditions of the press as it relates to various print quality issues. Even though paper is in competition with electronic media, high quality printed products are still in demand. The results should provide useful information for this segment of the industry.

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The rural electrification is characterized by geographical dispersion of the population, low consumption, high investment by consumers and high cost. Moreover, solar radiation constitutes an inexhaustible source of energy and in its conversion into electricity photovoltaic panels are used. In this study, equations were adjusted to field conditions presented by the manufacturer for current and power of small photovoltaic systems. The mathematical analysis was performed on the photovoltaic rural system I-100 from ISOFOTON, with power 300 Wp, located at the Experimental Farm Lageado of FCA/UNESP. For the development of such equations, the circuitry of photovoltaic cells has been studied to apply iterative numerical methods for the determination of electrical parameters and possible errors in the appropriate equations in the literature to reality. Therefore, a simulation of a photovoltaic panel was proposed through mathematical equations that were adjusted according to the data of local radiation. The results have presented equations that provide real answers to the user and may assist in the design of these systems, once calculated that the maximum power limit ensures a supply of energy generated. This real sizing helps establishing the possible applications of solar energy to the rural producer and informing the real possibilities of generating electricity from the sun.

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The aim of this study was to compare the hydrographically conditioned digital elevation models (HCDEMs) generated from data of VNIR (Visible Near Infrared) sensor of ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer), of SRTM (Shuttle Radar Topography Mission) and topographical maps from IBGE in a scale of 1:50,000, processed in the Geographical Information System (GIS), aiming the morphometric characterization of watersheds. It was taken as basis the Sub-basin of São Bartolomeu River, obtaining morphometric characteristics from HCDEMs. Root Mean Square Error (RMSE) and cross validation were the statistics indexes used to evaluate the quality of HCDEMs. The percentage differences in the morphometric parameters obtained from these three different data sets were less than 10%, except for the mean slope (21%). In general, it was observed a good agreement between HCDEMs generated from remote sensing data and IBGE maps. The result of HCDEM ASTER was slightly higher than that from HCDEM SRTM. The HCDEM ASTER was more accurate than the HCDEM SRTM in basins with high altitudes and rugged terrain, by presenting frequency altimetry nearest to HCDEM IBGE, considered standard in this study.

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BACKGROUND: A new procedure for the treatment of esophageal fistula, mainly associated to the ebb esophagojejunal in patients submitted to the total gastrectomy and reconstruction with loop jejunal Rouxen-Y anastomosis is present. METHODS: The method is based in the use of "probe standard enteral prolongated with drain to laminate adapted in extremity", which results in advanced positioning inside the jejunum, making the administration of enteral nutrition possible and impeding ebb esophagojejunal. RESULTS: The authors discuss the theoretical advantages of the procedure and they suggest that the treatment of esofagic fistula with probe prolonged enteral would be suitable in the treatment of the fistula esophagojejunal by preventing the ebb esophagojejunal, which would result in smaller period of duration of the fistula esophagojejunal and it would prevent the high mortality rate. CONCLUSIONS: Preliminary studies demonstrated that this is a technically easy, low cost procedure through the endoscopic use. A prospective evaluation for morbility and mortality related to the method is needed.

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Rapid depletion of easy-to-access fossil fuel, predominantly, oil and gas resources has now necessitated increase in need to develop new oil and gas sources in ever more remote and hostile environments. This is necessary in order to explore more oil and gas resources to meet rapidly rising long-term energy demand in the world, both at present and in the nearest future. Arctic is one of these harsh environments, where enormous oil and gas resources are available, containing about 20% of the world total oil and gas, but the environmental conditions are very harsh and hostile. However, virtually all the facilities required for the exploration and development of this new energy source are constructed with metals as well as their alloys and are predominantly joined together by welding processes and technologies. Meanwhile, due to entirely different environment from the usual moderate temperate region, conventional welding technologies, common metals and their alloys cannot be applied as this Arctic environment demand metals structures with very high toughness and strength properties under extremely low temperature. This is due to the fact that metals transit from ductility to brittleness as the temperature moves toward extreme negative values. Hence, this research work investigates and presents the advanced welding technologies applicable to Arctic metal structures which can give satisfactory weldments under active Arctic service conditions. .

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OBJETIVO: avaliar a morbidade e a mortalidade cirúrgica em pacientes submetidos a gastroduodenopancreatectomia (GDP) com linfadenectomia padrão e radical para adenocarcinoma de papila, analisando os fatores prognósticos com relação à sobrevida global e livre de doença. MÉTODOS: foram analisados retrospectivamente no período de 1999 a 2007, no Serviço de Cirurgia Abdômino-Pélvica do INCa-RJ, 50 casos de GDP para adenocarcinoma da papila duodenal divididos em dois grupos de acordo com a linfadenectomia (grupo A: linfadenectomia padrão e grupo B: linfadenectomia radical). RESULTADOS: A mediana de idade foi semelhante nos dois grupos, assim como a distribuição entre os sexos. Na comparação entre as linfadenectomias somente o número de linfonodos ressecados (grupo A: 12,3 e grupo B: 26,5) e o tempo operatório (grupo A: 421 e grupo B: 474) foram significativamente diferentes. Não ocorreram diferenças estatisticamente significativas nos dois grupos com relação a morbi-mortalidade operatória e tempo de internação. A sobrevida livre de doença (grupo A: 35 meses e grupo B: 51 meses) e sobrevida global (grupo A: 38 meses e grupo B: 53 meses) foi maior no grupo da linfadenectomia radical, porém não foram significantes estatisticamente. CONCLUSÃO: no presente estudo não ocorreram casos de linfonodos metastáticos para outros grupos nodais sem o acometimento linfonodal das cadeias pancreato-duodenais (13 e 17), sugerindo um padrão de disseminação linfonodal. Apesar da linfadenectomia radical apresentar taxas de sobrevida livre de doença e sobrevida global maiores esses dados não foram significativos estatisticamente. Novos estudos devem ser realizados para avaliar o real papel da linfadenectomia radical no adenocarcinoma da papila duodenal.

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Supporting patients with acute respiratory distress syndrome (ARDS), using a protective mechanical ventilation strategy characterized by low tidal volume and limitation of positive end-expiratory pressure (PEEP) is a standard practice in the intensive care unit. However, these strategies can promote lung de-recruitment, leading to the cyclic closing and reopening of collapsed alveoli and small airways. Recruitment maneuvers (RM) can be used to augment other methods, like positive end-expiratory pressure and positioning, to improve aerated lung volume. Clinical practice varies widely, and the optimal method and patient selection for recruitment maneuvers have not been determined, considerable uncertainty remaining regarding the appropriateness of RM. This review aims to discuss recent findings about the available types of RM, and compare the effectiveness, indications and adverse effects among them, as well as their impact on morbidity and mortality in ARDS patients. Recent developments include experimental and clinical evidence that a stepwise extended recruitment maneuver may cause an improvement in aerated lung volume and decrease the biological impact seen with the traditionally used sustained inflation, with less adverse effects. Prone positioning can reduce mortality in severe ARDS patients and may be an useful adjunct to recruitment maneuvers and advanced ventilatory strategies, such noisy ventilation and BIVENT, which have been useful in providing lung recruitment.

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Objective: To analyze the late results of advanced Chagasic megaesophagus treatment by esophagectomy associated with the use of proton pump inhibitor (omeprazole) as for the incidence of esophagitis and Barrett's esophagus in the remaining stump. Methods : We studied patients with advanced megaesophagus undergoing esophagectomy and transmediastinal esophagogastroplasty. Patients were divided into three groups: A (20) with esophageal replacement by full stomach, without the use of omeprazole; B (20) with esophageal replacement by full stomach, with omeprazole 40 mg/day introduced after the first postoperative endoscopy and maintained for six years; and C (30) with esophageal replacement by gastric tube with use of omeprazole. Dysphagia, weight loss and BMI were clinical parameters we analyzed. Upper gastrointestinal endoscopy was performed in all patients, and determined the height of the anastomosis, the aspect of the mucosa, with special attention to possible injuries arising from gastroesophageal reflux, and the patency of the esophagogastric anastomosis. Results : We studied 50 patients, 28 males (56%) and 22 (44%) females. All underwent endoscopy every year. In the first endoscopy, erosive esophagitis was present in nine patients (18%) and Barrett's esophagus, in four (8%); in the last endoscopy, erosive esophagitis was present in five patients (8%) and Barrett's esophagus in one (2%). When comparing groups B and C, there was no evidence that the manufacturing of a gastric tube reduced esophagitis and Barrett's esophagus. However, when comparing groups A and C, omeprazole use was correlated with reduction of reflux complications such as esophagitis and Barrett's esophagus (p <0.005). Conclusion : The use of omeprazole (40 mg/day) reduced the onset of erosive esophagitis and Barrett's esophagus during the late postoperative period.

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Cervical cancer remains the most frequent gynecological tumor in Brazil and other developing countries. Minimally invasive techniques, especially laparoscopy, have been increasingly employed in such tumors. This article aims to describe the main applications of laparoscopy in the treatment and staging of cervical cancer. In the early stages, it is possible to provide a fertility-preserving surgery in the form of radical trachelectomy and, in a study protocol, the function-preserving surgery, avoiding parametrectomy and the associated morbidity. A fully laparoscopic radical hysterectomy is fairly standard in the literature and has the tendency to become the standard of care in early cases, for patients who want to bear no more children. In advanced stages, minimally invasive surgery can offer ovarian transposition, with intent to prevent actinic castration, without upsetting the time for the start of radiotherapy and chemotherapy. Staging laparoscopic surgery, including pelvic and para-aortic lymphadenectomy, has been the subject of studies, since it has the potential to modify the extension of radiotherapy depending on the extent of lymph node spread.

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The thesis develops guidelines for the implementation of the health and safety management system according to the OHSAS 18001 standard, as well as the feasible threat analysis, project proposal schedule, future system quality improvements and organizational change evaluation. The theoretical part clarifies determination of occupational health and safety, its management system, the OHSAS 18001 standard and integrated management system compounded of triple ISO 14001, ISO 9001 and OHSAS 18001 standards. The literature includes such important aspects as human factor, organizational policies, possible benefits, threats, organizational safety culture, Deming’s quality improvement cycle, system implementation, maintenance and cost matters. The empirical part demonstrates real-life situation by using Andritz Pulp & Paper Oy as a case study. Prior the thesis proposal, Andritz Group is analysed including separate business areas, acquisition and integration strategies, current status of the health and safety management and parallel experiences of the largest business area Andritz Hydro. The proposal is aimed at improving the current health and safety system for the permanent and sub-contracted employees at Andritz Pulp & Paper both in Finland and in various projects globally.

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kuv., 16 x 25 cm

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kuv., 10 x 22 cm