New fuel cells system for portable application with low temperature cofired ceramic (LTCC) technology

Miniature direct methanol fuel cells (DMFCs) are promising micro power sources for portable appliction. Low temperature cofired ceramic (LTCC), a competitive technology for current MEMS based fabrication, provides cost-effective mass manufacturing route for miniature DMFCs. Porous silver tape is adapted as electrodes to replace the traditional porous carbon electrodes due to its compatibility to LTCC processing and other electrochemical advantages. Electrochemical evaluation of silver under DMFCs operating conditions demonstrated that silver is a good electrode for DMFCs because of its reasonable corrosion resistance, low passivating current, and enhanced catalytic effect. Two catalyst loading methods (cofiring and postfiring) of the platinum and ruthenium catalysts are evaluated for LTCC based processing. The electrochemical analysis exhibits that the cofired path out-performs the postfiring path both at the anode and cathode. The reason is the formation of high surface area precipitated whiskers. Self-constraint sintering is utilized to overcome the difficulties of the large difference of coefficient of thermal expansion (CTE) between silver and LTCC (Dupont 951) tape during cofiring. The graphite sheet employed as a cavity fugitive insert guarantees cavity dimension conservation. Finally, performance of the membrane electrode assembly (MEA) with the porous silver electrode in the regular graphite electrode based cell and the integrated cofired cell is measured under passive fuel feeding condition. The MEA of the regular cell performs better as the electrode porosity and temperature increased. The power density of 10 mWcm-2 was obtained at ambient conditions with 1M methanol and it increased to 16 mWcm -2 at 50°C from an open circuit voltage of 0.58V. For the integrated prototype cell, the best performance, which depends on the balance methanol crossover and mass transfer at different temperatures and methanol concentrations, reaches 1.13 mWcm-2 at 2M methanol solution at ambient pressure. The porous media pore structure increases the methanol crossover resistance. As temperature increased to 60°C, the device increases to 2.14 mWcm-2.

Efficient asynchronous scheduling algorithms for cost-effective buffered crossbar switches

Buffered crossbar switches have recently attracted considerable attention as the next generation of high speed interconnects. They are a special type of crossbar switches with an exclusive buffer at each crosspoint of the crossbar. They demonstrate unique advantages over traditional unbuffered crossbar switches, such as high throughput, low latency, and asynchronous packet scheduling. However, since crosspoint buffers are expensive on-chip memories, it is desired that each crosspoint has only a small buffer. This dissertation proposes a series of practical algorithms and techniques for efficient packet scheduling for buffered crossbar switches. To reduce the hardware cost of such switches and make them scalable, we considered partially buffered crossbars, whose crosspoint buffers can be of an arbitrarily small size. Firstly, we introduced a hybrid scheme called Packet-mode Asynchronous Scheduling Algorithm (PASA) to schedule best effort traffic. PASA combines the features of both distributed and centralized scheduling algorithms and can directly handle variable length packets without Segmentation And Reassembly (SAR). We showed by theoretical analysis that it achieves 100% throughput for any admissible traffic in a crossbar with a speedup of two. Moreover, outputs in PASA have a large probability to avoid the more time-consuming centralized scheduling process, and thus make fast scheduling decisions. Secondly, we proposed the Fair Asynchronous Segment Scheduling (FASS) algorithm to handle guaranteed performance traffic with explicit flow rates. FASS reduces the crosspoint buffer size by dividing packets into shorter segments before transmission. It also provides tight constant performance guarantees by emulating the ideal Generalized Processor Sharing (GPS) model. Furthermore, FASS requires no speedup for the crossbar, lowering the hardware cost and improving the switch capacity. Thirdly, we presented a bandwidth allocation scheme called Queue Length Proportional (QLP) to apply FASS to best effort traffic. QLP dynamically obtains a feasible bandwidth allocation matrix based on the queue length information, and thus assists the crossbar switch to be more work-conserving. The feasibility and stability of QLP were proved, no matter whether the traffic distribution is uniform or non-uniform. Hence, based on bandwidth allocation of QLP, FASS can also achieve 100% throughput for best effort traffic in a crossbar without speedup.

Scheduling medical application workloads on virtualized computing systems

This dissertation presents and evaluates a methodology for scheduling medical application workloads in virtualized computing environments. Such environments are being widely adopted by providers of "cloud computing" services. In the context of provisioning resources for medical applications, such environments allow users to deploy applications on distributed computing resources while keeping their data secure. Furthermore, higher level services that further abstract the infrastructure-related issues can be built on top of such infrastructures. For example, a medical imaging service can allow medical professionals to process their data in the cloud, easing them from the burden of having to deploy and manage these resources themselves. In this work, we focus on issues related to scheduling scientific workloads on virtualized environments. We build upon the knowledge base of traditional parallel job scheduling to address the specific case of medical applications while harnessing the benefits afforded by virtualization technology. To this end, we provide the following contributions: (1) An in-depth analysis of the execution characteristics of the target applications when run in virtualized environments. (2) A performance prediction methodology applicable to the target environment. (3) A scheduling algorithm that harnesses application knowledge and virtualization-related benefits to provide strong scheduling performance and quality of service guarantees. In the process of addressing these pertinent issues for our target user base (i.e. medical professionals and researchers), we provide insight that benefits a large community of scientific application users in industry and academia. Our execution time prediction and scheduling methodologies are implemented and evaluated on a real system running popular scientific applications. We find that we are able to predict the execution time of a number of these applications with an average error of 15%. Our scheduling methodology, which is tested with medical image processing workloads, is compared to that of two baseline scheduling solutions and we find that it outperforms them in terms of both the number of jobs processed and resource utilization by 20–30%, without violating any deadlines. We conclude that our solution is a viable approach to supporting the computational needs of medical users, even if the cloud computing paradigm is not widely adopted in its current form.

Improving caches in consolidated environments

Memory (cache, DRAM, and disk) is in charge of providing data and instructions to a computer's processor. In order to maximize performance, the speeds of the memory and the processor should be equal. However, using memory that always match the speed of the processor is prohibitively expensive. Computer hardware designers have managed to drastically lower the cost of the system with the use of memory caches by sacrificing some performance. A cache is a small piece of fast memory that stores popular data so it can be accessed faster. Modern computers have evolved into a hierarchy of caches, where a memory level is the cache for a larger and slower memory level immediately below it. Thus, by using caches, manufacturers are able to store terabytes of data at the cost of cheapest memory while achieving speeds close to the speed of the fastest one.^ The most important decision about managing a cache is what data to store in it. Failing to make good decisions can lead to performance overheads and over-provisioning. Surprisingly, caches choose data to store based on policies that have not changed in principle for decades. However, computing paradigms have changed radically leading to two noticeably different trends. First, caches are now consolidated across hundreds to even thousands of processes. And second, caching is being employed at new levels of the storage hierarchy due to the availability of high-performance flash-based persistent media. This brings four problems. First, as the workloads sharing a cache increase, it is more likely that they contain duplicated data. Second, consolidation creates contention for caches, and if not managed carefully, it translates to wasted space and sub-optimal performance. Third, as contented caches are shared by more workloads, administrators need to carefully estimate specific per-workload requirements across the entire memory hierarchy in order to meet per-workload performance goals. And finally, current cache write policies are unable to simultaneously provide performance and consistency guarantees for the new levels of the storage hierarchy.^ We addressed these problems by modeling their impact and by proposing solutions for each of them. First, we measured and modeled the amount of duplication at the buffer cache level and contention in real production systems. Second, we created a unified model of workload cache usage under contention to be used by administrators for provisioning, or by process schedulers to decide what processes to run together. Third, we proposed methods for removing cache duplication and to eliminate wasted space because of contention for space. And finally, we proposed a technique to improve the consistency guarantees of write-back caches while preserving their performance benefits.^

Host and network optimizations for performance enhancement and energy efficiency in data center networks

Modern data centers host hundreds of thousands of servers to achieve economies of scale. Such a huge number of servers create challenges for the data center network (DCN) to provide proportionally large bandwidth. In addition, the deployment of virtual machines (VMs) in data centers raises the requirements for efficient resource allocation and find-grained resource sharing. Further, the large number of servers and switches in the data center consume significant amounts of energy. Even though servers become more energy efficient with various energy saving techniques, DCN still accounts for 20% to 50% of the energy consumed by the entire data center. The objective of this dissertation is to enhance DCN performance as well as its energy efficiency by conducting optimizations on both host and network sides. First, as the DCN demands huge bisection bandwidth to interconnect all the servers, we propose a parallel packet switch (PPS) architecture that directly processes variable length packets without segmentation-and-reassembly (SAR). The proposed PPS achieves large bandwidth by combining switching capacities of multiple fabrics, and it further improves the switch throughput by avoiding padding bits in SAR. Second, since certain resource demands of the VM are bursty and demonstrate stochastic nature, to satisfy both deterministic and stochastic demands in VM placement, we propose the Max-Min Multidimensional Stochastic Bin Packing (M3SBP) algorithm. M3SBP calculates an equivalent deterministic value for the stochastic demands, and maximizes the minimum resource utilization ratio of each server. Third, to provide necessary traffic isolation for VMs that share the same physical network adapter, we propose the Flow-level Bandwidth Provisioning (FBP) algorithm. By reducing the flow scheduling problem to multiple stages of packet queuing problems, FBP guarantees the provisioned bandwidth and delay performance for each flow. Finally, while DCNs are typically provisioned with full bisection bandwidth, DCN traffic demonstrates fluctuating patterns, we propose a joint host-network optimization scheme to enhance the energy efficiency of DCNs during off-peak traffic hours. The proposed scheme utilizes a unified representation method that converts the VM placement problem to a routing problem and employs depth-first and best-fit search to find efficient paths for flows.

Delay-sensitive service request scheduling for cloud computing

Cloud computing realizes the long-held dream of converting computing capability into a type of utility. It has the potential to fundamentally change the landscape of the IT industry and our way of life. However, as cloud computing expanding substantially in both scale and scope, ensuring its sustainable growth is a critical problem. Service providers have long been suffering from high operational costs. Especially the costs associated with the skyrocketing power consumption of large data centers. In the meantime, while efficient power/energy utilization is indispensable for the sustainable growth of cloud computing, service providers must also satisfy a user's quality of service (QoS) requirements. This problem becomes even more challenging considering the increasingly stringent power/energy and QoS constraints, as well as other factors such as the highly dynamic, heterogeneous, and distributed nature of the computing infrastructures, etc. ^ In this dissertation, we study the problem of delay-sensitive cloud service scheduling for the sustainable development of cloud computing. We first focus our research on the development of scheduling methods for delay-sensitive cloud services on a single server with the goal of maximizing a service provider's profit. We then extend our study to scheduling cloud services in distributed environments. In particular, we develop a queue-based model and derive efficient request dispatching and processing decisions in a multi-electricity-market environment to improve the profits for service providers. We next study a problem of multi-tier service scheduling. By carefully assigning sub deadlines to the service tiers, our approach can significantly improve resource usage efficiencies with statistically guaranteed QoS. Finally, we study the power conscious resource provision problem for service requests with different QoS requirements. By properly sharing computing resources among different requests, our method statistically guarantees all QoS requirements with a minimized number of powered-on servers and thus the power consumptions. The significance of our research is that it is one part of the integrated effort from both industry and academia to ensure the sustainable growth of cloud computing as it continues to evolve and change our society profoundly.^

Regime jurídico dos incentivos fiscais: uma análise à luz da ordem econômica

This scientific investigation begins with the recognition of the authorization granted by the Constitutional Legislator to the State for, relativizing its neutrality towards the private sector, intervene in the behavior of economic agents, through different means, including fiscal incentives and tax increases in order to achieve the objectives and directives of the Federal Constitution, as well as achieve the rights and guarantees also described in the Federal Constitution. Demonstrates, however, that this intervention in the private sector has the power to generate both salutary reflections as perverse and divorced goals from what was established by the Federal Constitution and Multilateral Agreements and this is the basis that justifies the relevance of the study: because of the urgency to provide a thorough analysis of the phenomenon of state intervention in the Economic Order, given the importance of its impacts, both for citizens' lives, as well as for the maintenance of the State established as it is nowadays. From this premise, this research examines the issue of tax policies adopted in the country, focusing on tax incentives, comparing its use with the principles of the Economic Order and the General Agreement on Tariffs and Trade - GATT analyzing whether these have been respected or if Brazil adopted unjustified protectionist measures. From this context, this research approximated different branches of the law, developed through literature review in areas such as constitutional law, economic law, tax law, financial law and law and economics. This study verifies the motivations and objectives that underlie the adopted justifications for the use of tax incentives, as well as its results, seeking to empirically answer if its use is reasonable and consistent with the terms enshrined in the Federal Constitution of 1988 and GATT. The answer to this research question will be sought through doctrinal analysis, jurisprudence and hard cases. Thus, the study begins with the historical evolution of extrafiscality, analyzes the principles that should guide the behavior of economic agents. Subsequently analyzes the legal regime of tax incentives and the results achieved by hard cases in which the tax policies with extrafiscal nature were adopted in order to demonstrate the positive and negative consequences arising from the adoption of this type of benefit

Vínculo empregatício: interpretação judicial do direito fundamental à relação de emprego protegida e seus efeitos

The Federal Constitution, in Article 1, sections III and IV, lifted the work as the foundation of the Federative Republic of Brazil, including work as a social guarantee in Article 6, listing in its Article 7 minimal guarantees role with respect to social rights of workers. Although elevated to constitutional rights, these social rights of workers have in the judicial interpretation of the characteristic elements of the employment relationship, sometimes a mismatch with the legal and constitutional order, when, in deciding not ponder such elements, causing damage economic and social benefits to all workers, thus affecting the very constitutional basis of worker protection, there is therefore situations in which there must be part of unavailability of rights by the employee. Therefore, identifying the characteristic elements of employment, means allow immediate legal finding about possible illegality perpetrated by the employer, precisely because the sentence recognizes be merely declaratory noting, therefore, the elements that make up the juridical system normative in order to establish the characterization of employment in step with the effective observance and guarantee of social rights and therefore the employer's performance limiter as pertains to hiring and employee dismissal. This point is it's main element of this work, which is fundamental for the exegesis of the theme to limit the autonomy of the will. There is no denying, therefore, the need to extend the effects of these guarantees in the employment contract. In this context, therefore, jumping the guarantees of employees, embodied in particular in the Consolidation of Labor Laws, and especially in the Federal Constitution and international protection instruments to ensure the fundamental right to secure employment relationship, where technological advancement, social and economic, reflect directly, such as the parassubordinação, and claiming more and more systematic resolutions, especially when evidence gaps' values, which elevate the debate about the need for increased use of precedents of order to support the judgments, often beset with aspects of unconstitutionality, all in compliance with the integration of standards, seeking legal enforcement of this bond and providing legal certainty, there emerged, so the essence of the theme: discuss to what extent the distortion of employment limits the effectiveness of social rights and what its legal effects, since the constitutional standard for social guarantees protects equally worker admission.

Politícas públicas no Brasil: o desafio de garantir os direitos da infância

The article talks about the challenge of the construction of public policies for the child in the age group from 0 to 6 years old in Brazil, in the perspective of the right guarantees. One can presuppose that to comprehend the development of these policies, it is necessary to analyze the historical route of its assistance, possibilities and limits. It is also important to consider the contradictory relationships of power present in society, and its influence in the building of the conception of child and childhood that are very far to be neutral words, so they are policies. In this point of view, this work analyzes the arrangement of the current policies of assistance to children, making clear the shape as they were reorganized by the neo liberal policies and set of instructions of international organizations. The studies show that, instead of public and universal policies, programs and actions are introduced based on the focus in the fight against poverty, made with low costs and questionable quality.

Plano de desenvolvimento sustentável e articulação de políticas públicas: o controle de políticas ambientais pelo poder judiciário

The right to the preservation of a healthy environment is perceived as a Fundamental Right, inserted in the National Constitution and referring to present and future generations. The preservation of the environment is directly connected to the right to Health and Human Dignity and, therefore, must be treated as a personal right, unavailable, claiming for a positive response from the Brazilian State, through the development of related public policies, control of potentially harmful economic activities, with special focus on the principles of precaution and solidarity. The Brazilian judiciary must thus be attentive to the guardianship of the Fundamental Right. The judiciary control over the execution of public policies is based on obeying the principle of the separation, independence and harmony between the Powers, however it should never deviate from the constitutional obligation of caring for the effectivation of the rights and guarantees within the Magna Carta. In the balance between the principle of human dignity, from which springs the right to a healthy environment and the principle of separation of powers, the former should prevail, maintaining the latter to a core minimum.

A responsabilidade civil extracontratual do estado na prestação de serviços públicos de saúde

This study aims to examine the Brazilian legal model for the non-contractual liability of the state in providing public health services, from the perspective of threedimensional theory of law. Up based on bibliographical and documentary research, with emphasis on legislation, doctrine and Brazilian jurisprudence, the following conclusions were reached. The right to health is typified in the Constitution as a social fundamental right, and understands the pretension to obtain from the State, the supply of goods or the provision of services that reduce the risk of disease and other health problems; or promote, protect and recover the physical and mental well-being. Once violated the fundamental right to health, provides the managed, among other fundamental guarantees, the non-contractual liability of the state. The provision of public services by the state can be made directly through the Direct or Indirect Public Administration, or by recourse to private entities. In any case, the provision of public health services is entirely subordinate to the principles of administrative law and should be fully funded by tax revenues. As the provision of public health services is part of the administrative activity of the State, there is no way to exclude the application of the guarantee of non-contractual liability of the state in the face of the damage suffered by administered as users of these services. Therefore, it applies the theory of administrative risk, even in the event of harmful and illegal state failure.

Entre as tramas da indústria da moda: argumentos sobre o trabalho escravo contemporâneo na sociedade de consumo

Even after its abolition, the slave labor still exists in the world. In a new socio-historic context, the shackles and slave quarters have been left behind, nowadays the workers are tempted, subjected to degrading conditions and have their rights retrenched. The contemporary slave labor has been emerging as subject of research in the Organizational Studies since the early 2000s, calling attention to many gaps to be filled about the way organizations all around the world use this practice. Contemporary slave labor is found in many and various economic activities, since coal to textile industries or even stores. In this dissertation, we have incorporated the consumption dimension to the field of Organizational Studies, discussing the modern slavery, aiming to understand the consumers’ point of view about this topic, that is, we have researched the consumers’ interpretations concerning the slave labor in the fashion industry. Our objective is to analyze consumer’s argumentative construction in the decision of buying or not products made by industries from the fashion field that were denounced because of slave labor usage. We have adopted fashion industry as research focus because it obscures the reflection of the consumers that feel like in a new world while shopping, a world of beauty and fantasy, seeking their own satisfaction. Furthermore, the Brazilian fashion industry is one of the biggest of the world (ABIT, 2015), with a huge symbolic strength in the country. We have realized a qualitative research using semi-structured interviews with 35 consumers to identify their arguments according to the criteria defined by Liakopoulos (2002): data, propositions, guarantees, supports and refutations. The data are the statements used by the interviewees categorically, that is, those which are clear in the interviews. The propositions are what qualifies and justifies the used data. The guarantees are related to the nature of the data, they are what gives the sense to the data and are introduced implicitly in the interviewee speech. The supports are universal premises introduced in order to legitimate the arguments. The refutations, when present, counter the used arguments. As results, we’ve found consumers who developed arguments pro-consumption and anti-consumption and who have defended ideas about the responsibility of different actors for the existence of this practice and for the fight against it. From these two categories: (1) pro-consumption – consume despite the complaints and (2) anti-consumption – don’t consume, because of the accusations; we have identified the following argumentative lines: skepticism, faultfinding and moral engagement. By the end, we have presented the interviewees’ argumentative construction and the obtained results.

O PRINCÍPIO DA GRATUIDADE ATIVA NO PROGRAMA DE ASSISTÊNCIA ESTUDANTIL DO INSTITUTO FEDERAL DE EDUCAÇÃO, CIÊNCIA E TECNOLOGIA DE SÃO PAULO (IFSP) – CAMPUS CUBATÃO

Este trabalho realizado, inicialmente, com base na análise de alguns documentos referentes à legislação educacional brasileira vigente tem por objetivo desenvolver uma investigação acerca da aplicabilidade da Assistência Estudantil dentro do Instituto Federal de Educação, Ciência e Tecnologia de São Paulo (IFSP). A partir da questão do Direito à Educação de todo cidadão, que está garantido em nossa Constituição Federal, o governo elaborou, no ano de 2010, o Programa Nacional de Assistência Estudantil (PNAES). Respaldados nesse Programa, o IFSP criou, em 2011, o Programa de Assistência Estudantil (PAE), dando validade e continuidade às ações desenvolvidas nos Campi para minimizar a evasão e o fracasso escolar, com vistas a garantir a permanência dos educandos no referido Instituto. Embora o PAE tenha sido implementado em todos os Campi do IFSP, no decorrer do presente trabalho analisamos e estudamos, exclusivamente, o Campus Cubatão, localizado na região da Baixada Santista devido a, dentre outros fatores, ter sido a primeira unidade descentralizada dos Institutos Federais do país. Assim, neste estudo, temos como objetivo analisar a estrutura de funcionamento do IFSP com o intuito específico de investigar o Campus de Cubatão, verificar as questões de Vulnerabilidade Social encontradas na destacada instituição, averiguar as ações do PAE que nascem do PNAES, observar a aplicabilidade desse programa com base no princípio da Gratuidade Ativa e do Direito à Educação de todo cidadão. Para tanto, utilizamos, fundamentalmente, além da legislação já mencionada, o princípio da Gratuidade Ativa de Melchior (2011) e o conceito de Vulnerabilidade Social proposto por Alves (1994) e por Abramovay (2002).

ENSINO DO FENÔMENO RELIGIOSO NA ESCOLA PÚBLICA: área de conhecimento necessária para uma sociedade secularizada

Ao estudarmos a evolução histórica e o panorama atual do ensino religioso no Brasil, nos deparamos hoje com o problema da exclusão mútua de duas visões do seu tratamento na escola pública: ou deve existir o ensino religioso confessional ou não deve existir nenhum tipo de ensino religioso. Superando uma visão de laicidade de abstenção ao afirmar que o religioso, por definição, não nos diz respeito ou não diz respeito à ciência, e admitindo uma laicidade de inteligência ao defender que é nosso dever ou dever da ciência compreendê-lo como expressão humana e social, o ensino do fenômeno religioso pode superar essas duas visões, a partir de uma base epistemológica sólida para esta área de conhecimento, como já é prevista pela nossa legislação. Ele garante o respeito à diversidade e à pluralidade cultural da sociedade brasileira e contribui para a compreensão do fenômeno religioso como “objeto de cultura”. Ele é capaz de subsidiar práticas de ensino do fenômeno religioso no sistema de ensino laico, sem prejuízo de sua laicidade, mas a favor dela. A educação laica para a cidadania não pode ignorar as religiões pela sua forte presença e função na sociedade. É preciso decodificar criticamente as representações e práticas religiosas em nome da convivência mais construtiva entre as pessoas e extrair das tradições religiosas valores que contribuam para a vida humana na sua plenitude. Este modelo de ensinar a religião como fenômeno antropológico, social e cultural pode ainda cumprir uma função específica no que se refere ao conhecimento de si mesmo (identidade) e do outro para a aceitação do diferente (alteridade) apontando para a construção de valores éticos e de cidadania. Esta pesquisa se baseia em um grande levantamento bibliográfico e entrevistas com especialistas em laicidade e ensino do religioso a partir da proposta de Régis Debray adotada na França. Ela nos leva a concluir que o ensino do fenômeno religioso na escola pública do Brasil não é apenas necessário, mas até indispensável, se queremos uma educação que contribua para a formação dos nossos alunos e alunas para a convivência solidária.

Realized Matrix-Exponential Stochastic Volatility with Asymmetry, Long Memory and Spillovers

The paper develops a novel realized matrix-exponential stochastic volatility model of multivariate returns and realized covariances that incorporates asymmetry and long memory (hereafter the RMESV-ALM model). The matrix exponential transformation guarantees the positivedefiniteness of the dynamic covariance matrix. The contribution of the paper ties in with Robert Basmann’s seminal work in terms of the estimation of highly non-linear model specifications (“Causality tests and observationally equivalent representations of econometric models”, Journal of Econometrics, 1988, 39(1-2), 69–104), especially for developing tests for leverage and spillover effects in the covariance dynamics. Efficient importance sampling is used to maximize the likelihood function of RMESV-ALM, and the finite sample properties of the quasi-maximum likelihood estimator of the parameters are analysed. Using high frequency data for three US financial assets, the new model is estimated and evaluated. The forecasting performance of the new model is compared with a novel dynamic realized matrix-exponential conditional covariance model. The volatility and co-volatility spillovers are examined via the news impact curves and the impulse response functions from returns to volatility and co-volatility.