No description available.

No description available.

This thesis focuses on contribution of users in innovation activities. Through the case analysis of a mid-small sized tech company specialized in technology testing, we study one of the main innovative projects, undertaken for a client. Employing interviews and questionnaires throughout our research, we identify characteristics of client-users who contribute substantially in the ideation development and testing of the new innovation. The company deviating from their routinized testing activities, integrate the knowledge generated by those users in a particular way. We observe, analyze and make a critique upon those knowledge integration strategies, implemented by the company at this stage. The study highlights how the firm responds to the stimulus of those users involvement, aiming to give an interpretation of the phenomenon.

The objective of this research was to investigate lead speciation in the soil/sediment-water environment and to better understand how the species affect lead mobility under different environmental conditions. The research involved both field soil and sediment samples as well as standard lead solutions. Field samples were fully characterized and extracted by aqueous and organic solvents. The results were compared and evaluated with the metal speciation model, MINTEQA2. Hydrolytic polymerization and organic complexation studies were conducted with standard lead solutions under controlled experimental conditions. Results of the field samples showed that pH, dissolved cations, ionic strength, dissolved organic matter, and nature of the soil/sediment matrix play major roles in the distribution and mobility of lead (Pb) from contaminated sites. In the aqueous equilibration experiment, the magnitude of Pb2+ solubilization was in the order of pH4>pH7>pH9. The results were in good agreement with MINTEQA2 predictions. An important finding of the research is the detection of Pb polymerization species under controlled experimental conditions. At pH 5.22, Pb polymeric species were formed at rate of 0.03 per day. The role of Pb complexation with organic matter was evaluated in both field and standard samples. Different methodologies showed three types of organically bound Pb. A very small fraction of Pb, in the ppb range, was extractable from the contaminated soil by polar organic solvents. Sequential extractions show that 16.6±1.4 % of the Pb is organically complexed. Complexation of Pb with fulvic acid provided new information on the extent of Pb association with soluble organic matter. The overall results of this research have provided new and useful information regarding Pb speciation in environmental samples. The results, in several instances, have provided verification of MINTEQA2 model's prediction. They also revealed areas of disagreement between the models prediction and the experimental results. A positive note regarding the experimental work done in the research is the verification of the mass balance in all the repeated experiments.

Solder joints provide both electrical and mechanical interconnections between a silicon chip and the packaging substrate in an electronic application. The thermomechanical cycling in the solder causes numerous reliability challenges, mostly because of the mismatch of the coefficient of thermal expansion between the silicon chip and the substrate. The actual transition to lead-free solders and the trend towards hotter-running, miniaturized and higher current density chips aggravate this situation. Therefore, improved solder joints, with higher resistance to creep and low cycle fatigue, are necessary for future generations of microelectronics. This study focuses on a thermomechanical behavior comparison between monolithic Sn-Ag-Cu, copper fiber and copper ribbon cylindrical reinforced solders. The composite solders were found to reduce the inelastic strain range of the joint relative to monolithic solder, but at the expense of increased stress range.

This thesis focuses on lead auditors’ differences in terms of client portfolios and  performances. First, lead auditors are surveyed and their responses on professional scepticism linked to their performances. Second, survey and archival data are combined to check whether self-control is related to performance. Third, lead auditors’ client portfolios are examined with regard to industry similarity, portfolio dispersion and client grouping. Finally, auditors’ independence is tested in the  private firm setting. Overall, the findings indicate that performance is not homogenous across lead auditors in the same (tier) audit firm(s), and that the characteristics of lead auditors and accounting firms are determinants that partly explain the differences. / Avhandlingen fokuserar på skillnader i klientportföljer och prestation mellan ansvariga (alternativt påskrivande) revisorer och består av fyra huvudsakliga delar (alternativt studier). I den första delen kopplas mått på professionell skepticism, som bygger på enkätsvar från ansvariga revisorer, till prestation. I den andra delen kombineras enkätdata med arkivdata för att undersöka sambandet mellan självkontroll och prestation. I den tredje delen analyseras revisorernas klientportföljer utifrån dimensionerna branschtillhörighet, klientgruppering och portföljspridning. I den sista delen genomförs tester av revisorns oberoende för uppdrag i privata företag. Sammantaget indikerar resultaten att prestation varierar mellan revisorer från samma revisionsbyrå och att egenskaper hos ansvariga revisorer och revisionsbyråer delvis kan förklara dessa skillnader.

This thesis is a study of the effects of lead placement and sample shape in the measurement of electrical resistivity.

No description available.

by Au Wing Shing. / Parallel title in Chinese characters. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 56-58). / Acknowledgements --- p.i / Abstract --- p.ii / Table of Content --- p.iii / Chapter CHATPER 1 : --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 ： --- EXPERIMENTAL SET-UP / Chapter A. --- General Description --- p.4 / Chapter B. --- Vacuum System and Chamber --- p.6 / Chapter C. --- Target Rotation and Motor Connection --- p.7 / Chapter D. --- Substrate Heating and Temperature Control --- p.8 / Chapter E. --- Pressure and Flow Control --- p.9 / Chapter CHAPTER 3 ： --- THICKNESS AND COMPOSITION DISTRIBUTIONS OF FILMS DEPOSITED AT ROOM TEMPERATURE / Chapter A. --- Experimental Details --- p.10 / Chapter B. --- Shape of the Plume --- p.12 / Chapter C. --- Effect of Laser Fluence --- p.15 / Chapter D. --- Investigation of the Pb Deficiency in the Deposited Film --- p.24 / Chapter E. --- Effect of Oxygen Pressure --- p.27 / Chapter CHAPTER 4 ： --- TARGET MODIFICATION AND DEPOSITION RATE / Chapter A. --- Introduction --- p.34 / Chapter B. --- Experimental Details --- p.40 / Chapter C.i. --- Result 1 : Normal Incidence Case --- p.41 / Chapter ii. --- Result 2 : 45° Incidence Case --- p.42 / Chapter D. --- Discussion --- p.43 / Chapter CHAPTER 5 : --- HIGH TEMPERATURE GROWTH ON DIFFERRENT KINDS OF SUBSTRATES / Chapter A. --- Introduction --- p.45 / Chapter B. --- Experimental Details --- p.47 / Chapter C. --- High Temperature Growth / Chapter i. --- Films grown on MgO (100) --- p.49 / Chapter ii. --- Films grown on Spinel --- p.50 / Chapter iii. --- Films grown on c-plane Sapphire --- p.51 / Chapter D. --- Discussion --- p.52 / Chapter CHAPTER 6 ： --- OVERALL CONCLUSION AND FURTHER WORKS --- p.54 / References --- p.56 / Appendix1 --- p.59 / Appendix2 --- p.61

As cirurgias radioguiadas, utilizando sondas com detectores de radiação, têm sido destaque na área médica na última década. Esta técnica consiste na marcação de lesões com uma substância radioativa, que injetada no paciente, concentra-se no tumor e auxilia a sua localização durante o ato cirúrgico. Entre as cirurgias radioguiadas, a identificação e exame do linfonodo sentinela, tem revolucionado a conduta de neoplasias em estádio inicial, quando estas estão sendo disseminadas pela via linfática. As condições impostas por uma cirurgia e a proximidade entre alguns linfonodos, exige das sondas, reduzidos diâmetros e capacidade de identificação individual destes linfonodos marcados com um radiofármaco. O mercado internacional fornece sondas adequadas com cristais cintiladores e com semicondutores de telureto de cádmio, CdTe, mas que algumas vezes carecem de uma pronta assistência técnica no mercado brasileiro devido a todo o conjunto ser importado. Este trabalho desenvolveu sondas com tecnologia nacional, utilizando cristais cintiladores de iodeto de césio dopado com tálio, CsI(Tl) e, em substituição aos cristais semicondutores de CdTe, o cristal de brometo de tálio, TlBr que é um meio semicondutor detector em desenvolvimento mundialmente, com vantagens em relação ao CdTe. Ambos os cristais utilizados foram crescidos no IPEN. Toda a eletrônica necessária, e em especial, o pré-amplificador, que constituía também um fator limitante para desenvolvimento destes tipos de sonda no país, foram desenvolvidos com componentes encontrados no mercado nacional. Medidas sistemáticas de resolução espacial, seletividade espacial, sensibilidade máxima e qualidade da blindagem foram realizadas para as sondas desenvolvidas. Os resultados mostraram que dois modelos de sonda, uma com o cristal de CsI(Tl) e outra com o semicondutor de TlBr atenderam as qualidades sugeridas pela literatura internacional para sondas cirúrgicas radioguiadas. / Radioguided surgery, using probes with radiation detectors, has been prominence in the medical area in the last decade. This technique consists in injecting a radioactive substance to concentrate in tumour and assist the localization during the surgical procedure. The radioguided surgeries allowing the identification of lymph node has revolutioned the behavior of tumour in initial stadium when are being spread by lymphatic way. The conditions imposed to the surgery due the proximity between some lymph nodes, demands of the probes, a small diameters and capacity of individual identification of these lymph nodes radiolabelled by a specific tracer. The international market supplies these probes with CdTe semiconductors and scintillators, but there is some time lack a promptly technical assistance in the Brazilian market. This work developed probes with national technology, using CsI(Tl) scintillators crystals and, in substitution to CdTe crystals semiconductors, the TlBr crystal, that is a new semiconductor detector in a world-wide development, with advantages in relation to the CdTe. Both crystals have been grown in IPEN. All the necessary electronics, specially, the preamplifier, that was also a restrictive factor for development of these types of probe in the country, have been developed with components found in the national market. Systematic measures of spatial resolution, spatial selectivity, maximum sensitivity and quality of the shielding have been carried the probes development. The results have shown that the probes, one with the CsI(Tl) crystal and another with TlBr semiconductor presented the requested performance in the international literature for radiguided probes.