Wideband CMOS low noise amplifiers

Modern fully integrated receiver architectures, require inductorless circuits to achieve their potential low area, low cost, and low power. The low noise amplifier (LNA), which is a key block in such receivers, is investigated in this thesis. LNAs can be either narrowband or wideband. Narrowband LNAs use inductors and have very low noise figure, but they occupy a large area and require a technology with RF options to obtain inductors with high Q. Recently, wideband LNAs with noise and distortion cancelling, with passive loads have been proposed, which can have low NF, but have high power consumption. In this thesis the main goal is to obtain a very low area, low power, and low-cost wideband LNA. First, it is investigated a balun LNA with noise and distortion cancelling with active loads to boost the gain and reduce the noise figure (NF). The circuit is based on a conventional balun LNA with noise and distortion cancellation, using the combination of a common-gate (CG) stage and common-source (CS) stage. Simulation and measurements results, with a 130 nm CMOS technology, show that the gain is enhanced by about 3 dB and the NF is reduced by at least 0.5 dB, with a negligible impact on the circuit linearity (IIP3 is about 0 dBm). The total power dissipation is only 4.8 mW, and the active area is less than 50 x 50 m2 . It is also investigated a balun LNA in which the gain is boosted by using a double feedback structure.We propose to replace the load resistors by active loads, which can be used to implement local feedback loops (in the CG and CS stages). This will boost the gain and reduce the noise figure (NF). Simulation results, with the same 130 nm CMOS technology as above, show that the gain is 24 dB and NF is less than 2.7 dB. The total power dissipation is only 5.4 mW (since no extra blocks are required), leading to a figure-of-merit (FoM) of 3.8 mW

Laparoscopic versus open splenectomy in the management of hematologic diseases

Splenectomy is the best available treatment for severe forms of hereditary spherocytosis, idiopathic thrombocytopenic purpura, and other hematologic conditions when these prove refractory to conservative management. It has been employed for many decades with low mortality and favorable remission rates. The use of laparoscopic splenectomy in recent years has been rapidly and even enthusiastically adopted in this field. However, the exact role of laparoscopic versus open surgery for hematologic diseases is still debated. In this study of 58 adult patients, laparoscopic procedures were compared with conventional splenectomies for similar indications. METHODS: All patients were operated on within an 8-year period. Subjects underwent similar procedures under the supervision of the same surgical school and were compared regarding age, gender, body mass index, and diagnosis. Laparoscopically managed cases (Group I, n = 30) were prospectively followed according to a written protocol, whereas the same investigation was retrospectively done with regard to traditional laparotomy (Group II, n = 28). Methods included general and demographic findings, duration and technical steps of operation, blood loss, weight of spleen, need for conversion (in minimally invasive subjects), intraoperative and postoperative complications, time until realimentation, postoperative hospitalization, mortality, and late follow-up including recurrence rate. RESULTS: Idiopathic thrombocytopenic purpura was the surgical indication in over 50% of the patients in both groups, but familial spherocytosis, thalassemia, myelodysplasia, and lymphomas were also represented in this series. Laparoscopic procedures took more time to perform (P = 0.004), and postoperative hospitalization was 2 days shorter, but this difference was not statistically significant. Postoperative hematocrit and volume of blood transfusions was equivalent, although the laparoscopic cases had a somewhat lower preoperative hematocrit (NS) and displayed better recovery for this measurement (P = 0.03). More patients in Group I were able to accept oral food on the first day than subjects undergoing conventional operations (P < 0.05). Relatively few conversions were necessary during the minimally invasive surgeries (13.3%), and postoperative early and late complications as well as recurrences occurred in similar proportions. Also, the mean weight of the spleen was not statistically different between the groups, although there was a marked numerical tendency toward larger masses in conventional procedures. No spleen in Group I exceeded 2.0 kg, whereas in Group II values up to 4.0 kg occurred, and the mean weight was 50% higher in the latter group. CONCLUSIONS: 1) Minimally invasive splenectomy was essentially comparable to open surgery with regard to safety, efficacy, and late results; 2) Advantages concerning shorter postoperative hospitalization could not be shown, despite earlier food intake and a non-significant tendency toward earlier discharge; 3) This new modality should be considered an option in cases of hematologic conditions whenever the spleen is not hugely enlarged.

Urethral catheter removal 7 or 14 days after radical retropubic prostatectomy: clinical implications and complications in a randomized study

PURPOSE: To evaluate the hypothesis that a 7-day period of indwelling catheter after radical retropubic prostatectomy is effective and safe without the need of performing cystography. METHODS: In the period from January of 2000 to July of 2002, 73 patients underwent radical retropubic prostatectomy, and these patients were prospectively randomized in 2 groups: Group 1-37 patients who had the urethral catheter removed 7 days after the procedure, and Group 2-36 patients who had the catheter removed 14 days after the surgery. The 2 groups were similar, the surgeons and the technique were the same, and no cystography was performed to evaluate the presence of leaks. RESULTS: Two patients in Group 1 had bleeding and clot retention after having the catheter taken out in the seventh postoperative day and were managed by putting the catheter back in for 7 more days. Two patients in Group 2 developed bladder neck stricture and were treated by bladder neck incision with success. The continence rate was the same, with 2 cases of incontinence in each group. About 2 pads a day were used by the patients with incontinence. The average follow-up was 17.5 months (12-36 months). No urinary fistula, urinoma, or pelvic abscesses developed after catheter removal. Two patients were excluded from the analysis of this series: 1 died with a pulmonary embolus in the third postoperative day, and 1 developed a urinary suprapubic fistula before catheter withdrawal, which was maintained for 16 days. CONCLUSION: Withdrawal of the urethral catheter 7 days after radical retropubic prostatectomy, without performing cystography, has a low rate of short-term complications that are equivalent to withdrawal 14 days after the surgery.

Hybrid investment strategy active portfolio management – US stock market

This thesis aims to develop an alternative active managed portfolio strategy based on companies‟ Fundamental and Technical Analysis and analyze its finals results. There is a big distinction between the two approaches and the main objective is to understand if it is possible to take advantage of both. With this in mind a Hybrid investment strategy for the US stock market, due to its dimension and liquidity, which was able to outperform the S&P 500 index, the benchmark, during both Bear and Bull Markets between 2000 and 2015.

A negociação no mercado a prazo do MIBEL

This master thesis has been developed during the internship in the Supervision Department of Supervision of the Intermediation and Market Structures of CMVM. My collaboration in such department was mainly focused on the derivatives market of the Iberian Electricity Market (MIBEL). MIBEL embodies two organized markets – the derivatives market in Portugal and the spot market in Spain The trading activity in the derivatives market of MIBEL is processed through the trading platform of the regulated market managed by OMIP, however, much of the negotiation is over-the-counter. The aim of this work is to describe the market from a legal and economic perspective and to analyse the evolution of the negotiation, namely the impact of OTC in the regulated market trading. To achieve this, I propose to analyse also MiFID and EMIR rules over derivative contracts and the role of central counterparties, as they both are important to the discussion. In parallel, we found that OTC transactions are considerably higher than those traded in the regulated market managed by OMIP, those findings can be justified by the contractual relationships based on trust already established between the partiesarties. Nevertheless, since 2011 this trend changed by an increase of the registered OTC. Thereafter, although the parties continued to trade bilaterally, these transactions were registered in a central counterparty in order to eliminate the inherent risks related to the OTC derivatives transactions. This change in the negotiation pattern may also be influenced by the mandatory reporting of transactions imposed by EMIR, that requires for some classes of derivatives the centralized clearing and for all other requires the implementation of risk mitigation techniques.

Logoplaste: Conquering the world one bottle at a time

The “Logoplaste: Conquering the world one bottle at a time” case is based on the real story of the Botton family and their journey to build the globally known company Logoplaste. Famous for its “hole in the wall” strategy within the plastics industry, Logoplaste is not only one of the major plastic bottles manufacturers in the world, but also a company which has been proving us that a shared leadership system can be successful within a family business. This case intendeds to demonstrate the dynamics of a family business, illustrating the complexity of the decision making process and how they have successfully mastered dual management in a family firm. Moreover, it also aims to demonstrate that a family firm can be managed in such way that sustainable growth, as a key pillar, can be enabled through a strong focus on internationalization and innovation. A teaching note is available at the end of the case in order to guide students and teachers in their readings. Discussions questions, for debate in class environment, are also provided together with suggested answers drawn together to increase the critical sense and theoretical application of the themes studied in class.

A modinha brasileira : trajetória e veleidades (séculos XVIII-XX)

A modinha é um gênero musical que se encontra nas raízes musicais tanto de Portugal quanto do Brasil. Em ambos os países a modinha vem a se caracterizar como música nacional, mas as suas origens nos levam ao meio rural português dos séculos XVI e XVII e à chamada moda portuguesa. Após percorrer uma trajetória de cerca de duzentos anos, a modinha vem a desaparecer no século XX, no Brasil (enquanto em Portugal sua prática já havia sido abandonada em meados do século XIX), mas ainda assim deixando extenso legado. A modinha se adaptou a diferentes sociedades e períodos e assimilou diversos gêneros musicais, sendo de igual forma influenciada por diferentes correntes literárias. O gênero foi retratado por viajantes, religiosos, autoridades e esteve presente tanto nos saraus dos palácios da corte e dos salões das elites, quanto nas serenatas noturnas, entoadas por seresteiros. Procuramos aqui, através de grande variedade de fontes e documentos históricos remontar a trajetória da modinha, desde suas origens até sua dissipação, ressaltando ainda possíveis desvios que possa ter tomado, ao que chamamos de veleidades.

Contributions towards smart cities : exploring block level census data for the characterization of change in Lisbon

The interest in using information to improve the quality of living in large urban areas and its governance efficiency has been around for decades. Nevertheless, the improvements in Information and Communications Technology has sparked a new dynamic in academic research, usually under the umbrella term of Smart Cities. This concept of Smart City can probably be translated, in a simplified version, into cities that are lived, managed and developed in an information-saturated environment. While it makes perfect sense and we can easily foresee the benefits of such a concept, presently there are still several significant challenges that need to be tackled before we can materialize this vision. In this work we aim at providing a small contribution in this direction, which maximizes the relevancy of the available information resources. One of the most detailed and geographically relevant information resource available, for the study of cities, is the census, more specifically the data available at block level (Subsecção Estatística). In this work, we use Self-Organizing Maps (SOM) and the variant Geo-SOM to explore the block level data from the Portuguese census of Lisbon city, for the years of 2001 and 2011. We focus on gauging change, proposing ways that allow the comparison of the two time periods, which have two different underlying geographical bases. We proceed with the analysis of the data using different SOM variants, aiming at producing a two-fold portrait: one, of the evolution of Lisbon during the first decade of the XXI century, another, of how the census dataset and SOM’s can be used to produce an informational framework for the study of cities.

Life cycle analysis of zero waste management for Jonggol green city

A Zero waste management is believed to be one of methods to gain sustainability in urban areas. Take advantages of resources as enough as the needs and process it until the last part to be wasted is a contribution to take care the environment for the next generation. Reduce, reuse, and recycle are three simplesactivities which are until nowadays consideredas the back bone of zero waste. Jonggolgreen city is a new urban area in Indonesia with a 100 ha of surface area zoned as education tourism area. It is an independent area with pure natural resources of water, air, and land to be managed and protected. It is planned as green city through zero waste management since2013. In this preliminary period, a monitoring tool is being prepared by applying a Life Cycle Analysis (LCA) for urban areas [1]. This paper will present an explanatory assessment ofthe zero waste management for Jonggolgreen city. The existing situation will be examined through LCA and afterwards,the new program and the proposed green design to gain the next level of zero waste will be discussed. The purpose is to track the persistence of the commitment and the perception of the necessary innovationsin order to achieve the ideal behavior level of LCA.

Tecnologias da informação e comunicação na formação continuada de professores: estudode caso em escolas do Brasil e Portugal com recursos e aplicação do Google+

Tese de Doutoramento em Ciências da Educação (área de especialização em Tecnologia Educativa)

Seismic behaviour of traditional timber frame walls: experimental results on unreinforced walls

Timber frame buildings are well known as an efficient seismic resistant structure and they are used worldwide. Moreover, they have been specifically adopted in codes and regulations during the XVIII and XIX centuries in the Mediterranean area. These structures generally consist of exterior masonry walls with timber elements embedded which tie the walls together and internal walls which have a timber frame with masonry infill and act as shearwalls. In order to preserve these structureswhich characterizemany cities in theworld it is important to better understand their behaviour under seismic actions. Furthermore, historic technologies could be used even in modern constructions to build seismic resistant buildings using more natural materials with lesser costs. Generally, different types of infill could be applied to timber frame walls depending on the country, among which brick masonry, rubble masonry, hay and mud. The focus of this paper is to study the seismic behaviour of the walls considering different types of infill, specifically: masonry infill, lath and plaster and timber frame with no infill. Static cyclic tests have been performed on unreinforced timber frame walls in order to study their seismic capacity in terms of strength, stiffness, ductility and energy dissipation. The tests showed how in the unreinforced condition, the infill is able to guarantee a greater stiffness, ductility and ultimate capacity of the wall.

Application of near surface mounted (NSM) strengthening technique to traditional timber frame walls

Timber frame buildings are well known as an efficient seismic resistant structure popular all over the world not only due to their seismic performance, but also to their low cost and the strength they offer. These constructions still exist today and it is important to be able to preserve them, so a better knowledge on their behaviour is sought. Furthermore, historic technologies could be used even in modern constructions to build seismic resistant buildings using more natural materials with lesser costs. A great rehabilitation effort is being carried out on this type of buildings, as their neglect has led to decay or their change in use and alterations to the structure has led to the need to retrofit such buildings; only recently studies on their behaviour have become available and only a few of them address the issue of possible strengthening techniques for this kind of walls. In this scope, an innovative retrofitting technique (near surface mounted steel flat bars) is proposed and validated on traditional timber frame walls based on an extensive experimental program. The results of the static cyclic tests on distinct wall typologies retrofitted with the NSM technique are herein presented and discussed in detail. The main features on deformation, lateral stiffness, lateral resistance and seismic performance indexes are analysed

Insider threats: the major challenge to security risk management

Security risk management is by definition, a subjective and complex exercise and it takes time to perform properly. Human resources are fundamental assets for any organization, and as any other asset, they have inherent vulnerabilities that need to be handled, i.e. managed and assessed. However, the nature that characterize the human behavior and the organizational environment where they develop their work turn these task extremely difficult, hard to accomplish and prone to errors. Assuming security as a cost, organizations are usually focused on the efficiency of the security mechanisms implemented that enable them to protect against external attacks, disregarding the insider risks, which are much more difficult to assess. All these demands an interdisciplinary approach in order to combine technical solutions with psychology approaches in order to understand the organizational staff and detect any changes in their behaviors and characteristics. This paper intends to discuss some methodological challenges to evaluate the insider threats and its impacts, and integrate them in a security risk framework, that was defined according to the security standard ISO/IEC_JTC1, to support the security risk management process.

Tree species diversity in a seasonally-dry forest: the case of the Pinkaití site, in the Kayapó Indigenous Area, Southeastern limits of the Amazon

This study investigates patterns of forest structure and tree species diversity in an anthropogenic palm grove and undisturbed areas at the seasonally-dry Pinkaití research station, in the Kayapó Indigenous Area. This site, managed by the Conservation International do Brasil, is the most southeastern site floristically surveyed in the Amazon until now. The secondary and a nearby undisturbed forest were sampled in a group of 52 floristic plots of 0.0625-ha (25x25-m) where all trees with DBH > 10 cm were measured and identified. The analyses were complemented with other two floristic plots of 1-ha (10x1000-m). The present study has shown that the Pinkaití, like other seasonally-dry forests, have great heterogeneity in forest structure and composition, associated with biotic characteristics of the most important tree species, natural disturbance and history of land-use. The palm grove, moderately dominated by the arborescent palm Attalea maripa (Aubl.) Mart., presented high tree species diversity and was floristically similar to undisturbed forests at the study site. It is discussed the importance of large arborescent palms for the seasonally-dry Amazon forests regeneration.

Rockburst laboratory tests database - Application of data mining techniques

Rockburst is characterized by a violent explosion of a block causing a sudden rupture in the rock and is quite common in deep tunnels. It is critical to understand the phenomenon of rockburst, focusing on the patterns of occurrence so these events can be avoided and/or managed saving costs and possibly lives. The failure mechanism of rockburst needs to be better understood. Laboratory experiments are undergoing at the Laboratory for Geomechanics and Deep Underground Engineering (SKLGDUE) of Beijing and the system is described. A large number of rockburst tests were performed and their information collected, stored in a database and analyzed. Data Mining (DM) techniques were applied to the database in order to develop predictive models for the rockburst maximum stress (σRB) and rockburst risk index (IRB) that need the results of such tests to be determined. With the developed models it is possible to predict these parameters with high accuracy levels using data from the rock mass and specific project.