940 resultados para future energy scenario


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The purpose of this paper is to present the application of a three-phase harmonic propagation analysis time-domain tool, using the Norton model to approach the modeling of non-linear loads, making the harmonics currents flow more appropriate to the operation analysis and to the influence of mitigation elements analysis. This software makes it possible to obtain results closer to the real distribution network, considering voltages unbalances, currents imbalances and the application of mitigation elements for harmonic distortions. In this scenario, a real case study with network data and equipments connected to the network will be presented, as well as the modeling of non-linear loads based on real data obtained from some PCCs (Points of Common Coupling) of interests for a distribution company.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The purpose of this research was to present the principles for the implementation of a future water body classification program at the UGRHI-1 (Management Unit of Water Resources-1/São Paulo, Brazil) using qualitative and quantitative water modeling. Our study area was in Campos do Jordão, a city in the state of São Paulo, specifically in the Perdizes river watershed, which is included in the UGRHI-1. The water quality assessment used a modeling mehtodology that can support a future study for the classification of water bodies in the region. The behavior of DO and BOD parameters was assessed in the water quality scenarios, considering the variations of flows, loads, reductions in withdrawals and different efficiencies in sewage treatment. The model used was QUAL2E developed by USEPA (United States Environmental Protection Agency) that received a new graphic interface named QUAL2R model. The reference flows Q7,10, Q95% and Qm used were obtained through the DAEE (Department of Water and Electric Energy) hydrologic regionalization method. It was noted that of the 9 proposed scenarios, only scenario 6 that was predicted in the flow regime Qm with the existence of a treatment system capable of removing 93% of the BOD, in the Perdizes River remained 67.5% of the time in class 2. Scenario 8 predicted a 50% reduction in In scenario 8 a reduction of 50% in the flow captured in CA-04, associated with the efficiency of 93% of BOD removal keeping the river in class 2. In scenario 9 the minimum required efficiency in sewage treatment in the flow regime Q95% for keeping the river in class 2 was also calculated and the value of 94.7% was obtained.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In the wake of current global image involving environmental impacts, the use of wind power has had a remarkable growth in recent years as a technique for generating electricity. In fact, it is a source featuring strong dissemination of technology which provides decrease in costs and a greater access to low-income electricity. PROINFA (Incentive Program for Alternative Energy Sources) promotes a greater diffusion of new technologies for power generation, in particular wind-produced. Due to such a scenario on the exploitation of such energy source, current analysis discusses strategies for the development of domestic wind technology and the implications for electricity-lacking rural areas. Analysis shows a similar behavior between rural populations lacking electricity and the amount of potential energy available in the region. It is expected that this assay will contribute towards the establishment of public policies for wind-energy parks on rural farms in the North and Northeast regions of Brazil.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The availability of the electrical energy, in sufficient quantities and in competitive prices is a crucial factor to the economic development. The trade-in of the excess electrical energy produced in a system of cogeneration can be seen as an alternative to the creation of an additional source of revenues for ethanol power plants sector, besides contributing to the complementation of the Brazilian electrical headquarter with renewable sources. The objective of this study was to evaluate the economic feasibility of the implementation of a cogeneration electrical central using the excess of sugar cane bagasse and selling the excess of electrical energy with prices of the market. An ethanol power plant located in the state of Sao Paulo was used to this study. It was used the case study methodology, evaluating the potential of the investment under the viewpoint of the Net Present Value (NPV), Payback and Internal Rate of Return (IRR), and complementing the results of the Accounting Results (AC). It was created three alternative scenarios to reflect the level of the risk of every studied situation: the most likely, an optimistic and a pessimistic, each one with its assumptions. The Monte Carlo Simulations was used to insert the elements of risk to each scenario. The results showed that the project is feasible in all NPV scenarios. And the Payback and IRR analysis confirmed these evidences. The valuation with the AR showed that the project is most risky at the pessimistic scenario, but is feasibly in the most likely and the optimistic scenarios. It was concluded that the project is economic viable. However, the economic viability shown in the results is based on the maintenance of the future prices on the levels of the historical prices used in the analysis.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The principles and dimensions of sustainability concept is increasingly gaining ground within the building industry. Over the past decades, its applicability within the different environments and for different buildings typologies have been study to attend better the present populations and future generations. It is within this scenario that international certifications started to appear. The most famous and developed one being LEED certification system. In Brazil, as a support to the certification and also sustainability practices and conducts, was founded the Brazilian Council for Sustainable Construction (CBCS). The council and the certifications have the objective to disseminate and generate awareness to reduce energy and water consumption, aiming for life quality. Many constructions around de country have already the international certification, which also boost the rise of national certifications with specific criteria for the national context. However, such certificates are mainly destiny for medium and high standard buildings, often as a commercial advantage to explain the high costs. The purpose of this work is to be able to define what is being sustainable in the construction industry, taking for basis, LEED and CBCS. In addition, since there is a significant increase in the production of Housing Social Interest, the other angles will be to analyze how to apply the practices and sustainable technologies for low-cost projects with the objective to balance the three dimensions of sustainability: environmental, social and economics.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The principles and dimensions of sustainability concept is increasingly gaining ground within the building industry. Over the past decades, its applicability within the different environments and for different buildings typologies have been study to attend better the present populations and future generations. It is within this scenario that international certifications started to appear. The most famous and developed one being LEED certification system. In Brazil, as a support to the certification and also sustainability practices and conducts, was founded the Brazilian Council for Sustainable Construction (CBCS). The council and the certifications have the objective to disseminate and generate awareness to reduce energy and water consumption, aiming for life quality. Many constructions around de country have already the international certification, which also boost the rise of national certifications with specific criteria for the national context. However, such certificates are mainly destiny for medium and high standard buildings, often as a commercial advantage to explain the high costs. The purpose of this work is to be able to define what is being sustainable in the construction industry, taking for basis, LEED and CBCS. In addition, since there is a significant increase in the production of Housing Social Interest, the other angles will be to analyze how to apply the practices and sustainable technologies for low-cost projects with the objective to balance the three dimensions of sustainability: environmental, social and economics.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundamental principles of mechanics were primarily conceived for constant mass systems. Since the pioneering works of Meshcherskii (see historical review in Mikhailov (Mech. Solids 10(5):32-40, 1975), efforts have been made in order to elaborate an adequate mathematical formalism for variable mass systems. This is a current research field in theoretical mechanics. In this paper, attention is focused on the derivation of the so-called 'generalized canonical equations of Hamilton' for a variable mass particle. The applied technique consists in the consideration of the mass variation process as a dissipative phenomenon. Kozlov's (Stek. Inst. Math 223:178-184, 1998) method, originally devoted to the derivation of the generalized canonical equations of Hamilton for dissipative systems, is accordingly extended to the scenario of variable mass systems. This is done by conveniently writing the flux of kinetic energy from or into the variable mass particle as a 'Rayleigh-like dissipation function'. Cayley (Proc. R Soc. Lond. 8:506-511, 1857) was the first scholar to propose such an analogy. A deeper discussion on this particular subject will be left for a future paper.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The origin of cosmic rays at all energies is still uncertain. In this paper, we present and explore an astrophysical scenario to produce cosmic rays with energy ranging from below 10(15) to 3 x 10(20) eV. We show here that just our Galaxy and the radio galaxy Cen A, each with their own galactic cosmic-ray particles but with those from the radio galaxy pushed up in energy by a relativistic shock in the jet emanating from the active black hole, are sufficient to describe the most recent data in the PeV to near ZeV energy range. Data are available over this entire energy range from the KASCADE, KASCADE-Grande, and Pierre Auger Observatory experiments. The energy spectrum calculated here correctly reproduces the measured spectrum beyond the knee and, contrary to widely held expectations, no other extragalactic source population is required to explain the data even at energies far below the general cutoff expected at 6 x 10(19) eV, the Greisen-Zatsepin-Kuz'min turnoff due to interaction with the cosmological microwave background. We present several predictions for the source population, the cosmic-ray composition, and the propagation to Earth which can be tested in the near future.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In the framework of gauged flavour symmetries, new fermions in parity symmetric representations of the standard model are generically needed for the compensation of mixed anomalies. The key point is that their masses are also protected by flavour symmetries and some of them are expected to lie way below the flavour symmetry breaking scale(s), which has to occur many orders of magnitude above the electroweak scale to be compatible with the available data from flavour changing neutral currents and CP violation experiments. We argue that, actually, some of these fermions would plausibly get masses within the LHC range. If they are taken to be heavy quarks and leptons, in (bi)-fundamental representations of the standard model symmetries, their mixings with the light ones are strongly constrained to be very small by electroweak precision data. The alternative chosen here is to exactly forbid such mixings by breaking of flavour symmetries into an exact discrete symmetry, the so-called proton-hexality, primarily suggested to avoid proton decay. As a consequence of the large value needed for the flavour breaking scale, those heavy particles are long-lived and rather appropriate for the current and future searches at the LHC for quasi-stable hadrons and leptons. In fact, the LHC experiments have already started to look for them.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In many countries buildings are responsible for a substantial part of the energy consumption, nd it varies according to their energetic and environmental performances. The potential for major reductions in buildings consumption have bee well documented in Brazil. Opportunities have been identified throughout the life cycle of the buildings, due of projects in diverse locations without the proper adjustments. This article offers a reflection about project processes and how its understanding can be conducted in an integrated way, favoring the use of natural resources and lowering energy consumption. It concludes by indicating that the longest phase in the life cycle of a building is also the phase responsible for its largest energy consumption, not only because of its duration but also for the interaction with the end user. Therefore, in order to harvest the energy cost reduction potential from future buildings designers need a holistic view of the surrounding, end users, materials and methodologies.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

[EN] Today, science is difficult to pursue because funding is so tenuous. In such a financial climate, researchers need to consider parallel alternatives to ensure that scientific research can continue. Based on this thinking, we created BIOCEANSolutions, a company born of a research group. A great variety of environmental regulations and standards have emerged over recent years with the purpose of protecting natural ecosystems. These have enabled us to link our research to the market of environmental management. Marine activities can alter environmental conditions, resulting in changes in physiological states, species diversity, abundance, and biomass in the local biological communities. In this way, we can apply our knowledge, to plankton ecophysiology and biochemical oceanography. We measure enzyme activities as bio-indicators of energy metabolism and other physiological rates and biologic-oceanographic processes in marine organisms. This information provides insight into the health of marine communities, the stress levels of individual organisms, and potential anomalies that may be affecting them. In the process of verifying standards and complying with regulations, we can apply our analytic capability and knowledge. The main analyses that we offer are: (1) the activity of the electron transport system (ETS) or potential respiration (Φ), (2) the physiological measurement of respiration (oxygen consumption), (3) the activity of Isocitrate dehydrogenase (IDH), (4) the respiratory CO2 production, and (5) the activity of Glutamate dehydrogenase (GDH) and (6) the physiological measurement of ammonium excretion. In addition, our experience in a productive research group allows us to pursue and develop technical-experimental activities such as marine and freshwater aquaculture, oceanographic field sampling, as well as providing guidance, counseling, and academic services. In summary, this new company will permit us to create a symbiosis between public and private sectors that serve clients and will allow us to grow and expand as a research team.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Galaxy clusters occupy a special position in the cosmic hierarchy as they are the largest bound structures in the Universe. There is now general agreement on a hierarchical picture for the formation of cosmic structures, in which galaxy clusters are supposed to form by accretion of matter and merging between smaller units. During merger events, shocks are driven by the gravity of the dark matter in the diffuse barionic component, which is heated up to the observed temperature. Radio and hard-X ray observations have discovered non-thermal components mixed with the thermal Intra Cluster Medium (ICM) and this is of great importance as it calls for a “revision” of the physics of the ICM. The bulk of present information comes from the radio observations which discovered an increasing number of Mpcsized emissions from the ICM, Radio Halos (at the cluster center) and Radio Relics (at the cluster periphery). These sources are due to synchrotron emission from ultra relativistic electrons diffusing through µG turbulent magnetic fields. Radio Halos are the most spectacular evidence of non-thermal components in the ICM and understanding the origin and evolution of these sources represents one of the most challenging goal of the theory of the ICM. Cluster mergers are the most energetic events in the Universe and a fraction of the energy dissipated during these mergers could be channelled into the amplification of the magnetic fields and into the acceleration of high energy particles via shocks and turbulence driven by these mergers. Present observations of Radio Halos (and possibly of hard X-rays) can be best interpreted in terms of the reacceleration scenario in which MHD turbulence injected during these cluster mergers re-accelerates high energy particles in the ICM. The physics involved in this scenario is very complex and model details are difficult to test, however this model clearly predicts some simple properties of Radio Halos (and resulting IC emission in the hard X-ray band) which are almost independent of the details of the adopted physics. In particular in the re-acceleration scenario MHD turbulence is injected and dissipated during cluster mergers and thus Radio Halos (and also the resulting hard X-ray IC emission) should be transient phenomena (with a typical lifetime <» 1 Gyr) associated with dynamically disturbed clusters. The physics of the re-acceleration scenario should produce an unavoidable cut-off in the spectrum of the re-accelerated electrons, which is due to the balance between turbulent acceleration and radiative losses. The energy at which this cut-off occurs, and thus the maximum frequency at which synchrotron radiation is produced, depends essentially on the efficiency of the acceleration mechanism so that observations at high frequencies are expected to catch only the most efficient phenomena while, in principle, low frequency radio surveys may found these phenomena much common in the Universe. These basic properties should leave an important imprint in the statistical properties of Radio Halos (and of non-thermal phenomena in general) which, however, have not been addressed yet by present modellings. The main focus of this PhD thesis is to calculate, for the first time, the expected statistics of Radio Halos in the context of the re-acceleration scenario. In particular, we shall address the following main questions: • Is it possible to model “self-consistently” the evolution of these sources together with that of the parent clusters? • How the occurrence of Radio Halos is expected to change with cluster mass and to evolve with redshift? How the efficiency to catch Radio Halos in galaxy clusters changes with the observing radio frequency? • How many Radio Halos are expected to form in the Universe? At which redshift is expected the bulk of these sources? • Is it possible to reproduce in the re-acceleration scenario the observed occurrence and number of Radio Halos in the Universe and the observed correlations between thermal and non-thermal properties of galaxy clusters? • Is it possible to constrain the magnetic field intensity and profile in galaxy clusters and the energetic of turbulence in the ICM from the comparison between model expectations and observations? Several astrophysical ingredients are necessary to model the evolution and statistical properties of Radio Halos in the context of re-acceleration model and to address the points given above. For these reason we deserve some space in this PhD thesis to review the important aspects of the physics of the ICM which are of interest to catch our goals. In Chapt. 1 we discuss the physics of galaxy clusters, and in particular, the clusters formation process; in Chapt. 2 we review the main observational properties of non-thermal components in the ICM; and in Chapt. 3 we focus on the physics of magnetic field and of particle acceleration in galaxy clusters. As a relevant application, the theory of Alfv´enic particle acceleration is applied in Chapt. 4 where we report the most important results from calculations we have done in the framework of the re-acceleration scenario. In this Chapter we show that a fraction of the energy of fluid turbulence driven in the ICM by the cluster mergers can be channelled into the injection of Alfv´en waves at small scales and that these waves can efficiently re-accelerate particles and trigger Radio Halos and hard X-ray emission. The main part of this PhD work, the calculation of the statistical properties of Radio Halos and non-thermal phenomena as expected in the context of the re-acceleration model and their comparison with observations, is presented in Chapts.5, 6, 7 and 8. In Chapt.5 we present a first approach to semi-analytical calculations of statistical properties of giant Radio Halos. The main goal of this Chapter is to model cluster formation, the injection of turbulence in the ICM and the resulting particle acceleration process. We adopt the semi–analytic extended Press & Schechter (PS) theory to follow the formation of a large synthetic population of galaxy clusters and assume that during a merger a fraction of the PdV work done by the infalling subclusters in passing through the most massive one is injected in the form of magnetosonic waves. Then the processes of stochastic acceleration of the relativistic electrons by these waves and the properties of the ensuing synchrotron (Radio Halos) and inverse Compton (IC, hard X-ray) emission of merging clusters are computed under the assumption of a constant rms average magnetic field strength in emitting volume. The main finding of these calculations is that giant Radio Halos are naturally expected only in the more massive clusters, and that the expected fraction of clusters with Radio Halos is consistent with the observed one. In Chapt. 6 we extend the previous calculations by including a scaling of the magnetic field strength with cluster mass. The inclusion of this scaling allows us to derive the expected correlations between the synchrotron radio power of Radio Halos and the X-ray properties (T, LX) and mass of the hosting clusters. For the first time, we show that these correlations, calculated in the context of the re-acceleration model, are consistent with the observed ones for typical µG strengths of the average B intensity in massive clusters. The calculations presented in this Chapter allow us to derive the evolution of the probability to form Radio Halos as a function of the cluster mass and redshift. The most relevant finding presented in this Chapter is that the luminosity functions of giant Radio Halos at 1.4 GHz are expected to peak around a radio power » 1024 W/Hz and to flatten (or cut-off) at lower radio powers because of the decrease of the electron re-acceleration efficiency in smaller galaxy clusters. In Chapt. 6 we also derive the expected number counts of Radio Halos and compare them with available observations: we claim that » 100 Radio Halos in the Universe can be observed at 1.4 GHz with deep surveys, while more than 1000 Radio Halos are expected to be discovered in the next future by LOFAR at 150 MHz. This is the first (and so far unique) model expectation for the number counts of Radio Halos at lower frequency and allows to design future radio surveys. Based on the results of Chapt. 6, in Chapt.7 we present a work in progress on a “revision” of the occurrence of Radio Halos. We combine past results from the NVSS radio survey (z » 0.05 − 0.2) with our ongoing GMRT Radio Halos Pointed Observations of 50 X-ray luminous galaxy clusters (at z » 0.2−0.4) and discuss the possibility to test our model expectations with the number counts of Radio Halos at z » 0.05 − 0.4. The most relevant limitation in the calculations presented in Chapt. 5 and 6 is the assumption of an “averaged” size of Radio Halos independently of their radio luminosity and of the mass of the parent clusters. This assumption cannot be released in the context of the PS formalism used to describe the formation process of clusters, while a more detailed analysis of the physics of cluster mergers and of the injection process of turbulence in the ICM would require an approach based on numerical (possible MHD) simulations of a very large volume of the Universe which is however well beyond the aim of this PhD thesis. On the other hand, in Chapt.8 we report our discovery of novel correlations between the size (RH) of Radio Halos and their radio power and between RH and the cluster mass within the Radio Halo region, MH. In particular this last “geometrical” MH − RH correlation allows us to “observationally” overcome the limitation of the “average” size of Radio Halos. Thus in this Chapter, by making use of this “geometrical” correlation and of a simplified form of the re-acceleration model based on the results of Chapt. 5 and 6 we are able to discuss expected correlations between the synchrotron power and the thermal cluster quantities relative to the radio emitting region. This is a new powerful tool of investigation and we show that all the observed correlations (PR − RH, PR − MH, PR − T, PR − LX, . . . ) now become well understood in the context of the re-acceleration model. In addition, we find that observationally the size of Radio Halos scales non-linearly with the virial radius of the parent cluster, and this immediately means that the fraction of the cluster volume which is radio emitting increases with cluster mass and thus that the non-thermal component in clusters is not self-similar.