O plantio em ambiente protegido é incapaz de demonstrar seu máximo potencial de produção se não for submetido a um controle climático adequado. Existem hoje diversos tipos de equipamentos e metodologias que nos permitem desenvolver controles que monitorem o estado de conforto térmico da planta com uso racional de recursos e insumos. Dessa forma, é proposta uma metodologia de controle climático com integração de lógica fuzzy, controles lógicos programáveis e utilizando o cálculo de déficit de pressão de vapor folha-ar, como forma de se estimar o conforto térmico vegetal. Esta metodologia também utilizou métodos geoestatísticos (mapas de krigagem) para avaliação dos efeitos da aplicação das ações de controle sobre o clima interno, bem como monitorar o consumo de energia elétrica dos equipamentos. Foram realizados os testes em dois tratamentos em uma casa de vegetação comercial; e os dados confrontados para avaliação de sua eficiência no que se refere ao consumo de energia e mapas de krigagem das variáveis temperatura e umidade do ar; The protected culture is incapable to demonstrate its production maximum potential while not submitted to an adequate environment control. Nowadays, there are several equipments and methodologies which provides the control development with plant thermal comfort monitoring saving resources and inputs. This way...
Sistemas embarcados modernos são compostos de SoC heterogêneos, variando entre processadores de baixo e alto custo. Apesar de processadores RISC serem o padrão para estes dispositivos, a situação mudou recentemente: fabricantes estão construindo sistemas embarcados utilizando processadores RISC - ARM e MIPS - e CISC (x86). A adição de novas funcionalidades em software embarcados requer maior utilização da memória, um recurso caro e escasso em SoCs. Assim, o tamanho de código executável é crítico, porque afeta diretamente o número de misses na cache de instruções. Processadores CISC costumavam possuir maior densidade de código do que processadores RISC, uma vez que a codificação de instruções com tamanho variável beneficia as instruções mais usadas, os programas são menores. No entanto, com a adição de novas extensões e instruções mais longas, a densidade do CISC em aplicativos recentes tornou-se similar ao RISC. Nesta tese de doutorado, investigamos a compressibilidade de processadores RISC e CISC; SPARC e x86. Nós propomos uma extensão de 16-bits para o processador SPARC, o SPARC16. Apresentamos também, a primeira metodologia para gerar ISAs de 16-bits e avaliamos a compressão atingida em comparação com outras extensões de 16-bits. Programas do SPARC16 podem atingir taxas de compressão melhores do que outros ISAs...
A redução dos níveis de CO2 emitidos para a atmosfera, resultantes do consumo energético, vem constituindo ao longo dos últimos anos uma preocupação global. Neste sentido, a União Européia vem desenvolvendo um conjunto de documentos que visam a regulamentação da redução do consumo de energia e das emissões de gases com efeito estufa, e aumento da quota de energias renováveis até 2020. O uso de sistemas fotovoltaicos em fachadas se insere nesse contexto de aumento da quota de energias renováveis. Os ganhos que a fachada fotovoltaica apresenta são referentes à eficiência energética e ao desempenho ambiental dos edifícios. Diante desses aspectos foi executado um estudo para Portugal sobre uso de painéis fotovoltaicos em fachadas por meio de simulação computacional no qual foram analisadas as características dos painéis mais eficientes. Para alcançar tais resultados, a metodologia incluiu simulações computacionais realizadas com o software SolTerm 5.0. Com base nos resultados, observou-se que existe um potencial para o uso de painéis fotovoltaicos em Portugal, principalmente para latitudes próximas à Évora. Além disso, observou-se que o tipo de tecnologia com maior rendimento são os painéis de silício policristalino na posição inclinada...
The climate and energy package is a set of binding legislations which aims to ensure the European Union meets its ambitious climate and energy targets for 2020. These targets, known as the "20-20-20" targets, have set three key objectives: a 20% reduction in the EU greenhouse gas emissions, a 20% rise in the share of EU energy consumption produced from renewable resources and a 20% improvement in the energy efficiency. More renewable energies will enable the EU to lower greenhouse emissions and make it less dependent on imported energy. Boosting the industry of renewables will encourage technological innovation and employment in Europe. On this topic, photovoltaic façades are known to be a solution that allows both energy efficiency and environmental performance of buildings. This paper reports on a study of façade systems that have incorporated photovoltaic panels, considering computational simulations for Portugal. The main objective is to analyze the characteristics and parameters that define more efficient systems based on computer simulations carried out by Solterm 5.0. The results show the high potential of the use of the proposed technology in Portugal, especially in the Southern region, because of its latitude. Regarding energy efficiency and environmental performance...
As entidades gestoras de sistemas de abastecimento de água (SAA) enfrentam, atualmente, grandes desafios na promoção da gestão sustentável dos recursos, nomeadamente a água e a energia. Os custos associados à operação e manutenção dos SAA têm vindo a aumentar devido, principalmente, aos custos crescentes da eletricidade e ao envelhecimento dos componentes dos sistemas pelo aumento das perdas físicas de água e das perdas de carga. Estes aumentos de custos não são reflectidos totalmente nos tarifários. As perdas de água são predominantes nos sistemas com maior período de vida, podendo em algumas entidades atingir a ordem dos 50% (BATISTA, 2012).
A organização The Alliance to Save Energy estimou que a energia utilizada em sistemas de abastecimento de água, nomeadamente nas estações elevatórias e nas estações de tratamento de água, é cerca de 2 a 3 % da energia consumida no mundo, com um potencial de redução da energia consumida de cerca de 25%, desde que aplicadas medidas de eficiência energética (WATERGY, 2003).
O trabalho aqui apresentado tem como objetivo o estudo de uma solução híbrida de produção de energias renováveis, de modo a melhorar a eficiência energética do sistema de abastecimento de água de Arcos...
The mass attenuation and energy-absorption coefficients (radiation interaction data), which are widely used in the shielding and dosimetry of X-rays used for medical diagnostic and orthovoltage therapeutic procedures, are strongly dependent on the energy of photons, elements and percentage by weight of elements in body tissues and substitutes. Significant disparities exist in the values of percentage by weight of elements reported in literature for body tissues and substitutes for individuals of different ages, genders and states of health. Often, interested parties are in need of these radiation interaction data for body tissues or substitutes with percentage by weight of elements and intermediate energies that are not tabulated in literature. To provide for the use of more precise values of these radiation interaction data, parameters and computer programs, MUA_T and MUEN_T are presented for the computation of mass attenuation and energy-absorption coefficients for body tissues and substitutes of arbitrary percentage-by-weight elemental composition and photon energy ranging between 1 keV (or k-edge) and 400 keV. Results are presented, which show that the values of mass attenuation and energy-absorption coefficients obtained from computer programs are in good agreement with those reported in literature.
This thesis, directed toward a wide variety of persons interested in energy efficiency issues with office technology, explores several issues relating to reducing energy use and improving energy efficiency of office equipment. Chapter 2 compares policies and programs in several European countries and the United States that could enhance the energy efficiency of office technology. Different programs are examined, including federal government programs where in some cases target values for power usage of office equipment have already been set. Large customer procurement programs, industry involvement, with emphasis on voluntary labeling programs, and research projects are also examined. Procedures that provide energy consumption measurements of various types of equipment are important for providing information to emerging procurement programs. Two sets of proposed test procedures for testing energy consumption of copiers, fax machines and printers are examined and compared. In Chapter 3, comparisons are made of the electrical power and energy used by computers, displays, copiers, printers and facsimile machines, both while operating and while idle. Technology options for reduced energy and power consumption and improved energy efficiency are examined. As the capability of office equipment has increased...
Sensor management may be defined as those stochastic control problems in which control values are selected to influence sensing parameters in order to maximize the utility of the resulting measurements for an underlying detection or estimation problem. While problems of this type can be formulated as a dynamic program, the state space of the program is in general infinite, and traditional solution techniques are inapplicable. Despite this fact, many authors have applied simple heuristics such as greedy or myopic controllers with great success. This thesis studies sensor management problems in which information theoretic quantities such as entropy are utilized to measure detection or estimation performance. The work has two emphases: Firstly, we seek performance bounds which guarantee performance of the greedy heuristic and derivatives thereof in certain classes of problems. Secondly, we seek to extend these basic heuristic controllers to nd algorithms that provide improved performance and are applicable in larger classes of problems for which the performance bounds do not apply. The primary problem of interest is multiple object tracking and identification; application areas include sensor network management and multifunction radar control.; (cont.) Utilizing the property of submodularity...
This work presents an approach to control demand for residential low voltage consumers, aiming to improve energy efficiency in Smart Grids. Initially, an emulator of residential electric loads is modeled based on the literature. The emulator consists of a reservoir for water heating model, the model of an air conditioner and also models of consumption for lighting, televisions and a refrigerator. The implementation and simulation were performed using software Matlab. The demand control algorithms are investigated in order to verify its performance when applied to the set of residential loads. These algorithms typically perform control demand from a system of priorities. Still, from this analysis it demonstrates that these algorithms consider levels of user comfort, but do not allow the drive of two or more loads in the same period of residence if the demand exceeds the limit. Therefore, we propose a control algorithm that uses Rosenbrock search of demand adaptive method, aiming to overcome these limitations. The proposed procedure performs the operation of residential loads gradually considering priority levels and parameters of comfort of users. It is shown through simulations and experiments using the proposed method can perform the activation of several concurrently loads...
The burnup neutronics of uniform PWR lattices are examined with respect to reduction of uranium ore requirements with an emphasis on variation of the fuel-to-moderator ratio
(lattice pitch at constant fuel pin diameter) and the use of thorium. Fuel cycles using all combinations of the major fissile (U-235, U-233, Pu) and fertile (U-238, Th) species
The LEOPARD code and prescriptions developed from a linear reactivity model are used to determine initial core and annual makeup fissile requirements for input into an
in-house, simple, systems model, MASFLO-2, which calculates ore (and separative work) requirements per GWeyr for growing,
declining, or finite-life nuclear electric systems. For low growth scenarios drier lattices are favored, and the thorium
fuel cycle requires as much as 23% less ore than a comparably optimized uranium cycle with full recycle. For unmodified
lattices, the thorium fuel cycle with full recycle exhibits long term uranium ore savings of 17% over the comparable
uranium cycle with full recycle. For rapidly growing systems, drier lattices, and those using thorium, are less attractive
because of their high startup inventories. Thus the introduction of thorium may increase ore and separative work requirements in the short term but will more than repay the
ore investment in the very long term.
Very little improvement was achieved by varying fuel pin diameter at a given fuel-to-moderator ratio...
The WOSUB-codes are spin-offs and extensions of the
MATTEO-code . The series of three reports describe WOSUB-I
and WOSUB-II in their respective status as of July 31, 1977.
This report is the third in a series of three, the
first of which  contains all the information about the
models, solution methods and constitutive equations and the
second  being the user's manual of the code.
This report summarizes the assessment of the WOSUB-
code against experiments and compares its results with the
results of other subchannel codes. The following experiments
are used for the purpose of the assessment of the code under
1) 9-rod GE-tests with radially uniform and non-
uniform peaking factor patterns.
2) 16-rod Columbia tests with slight power tilts.
3) Planned 9-rod Swedish tests with very strong
4) Actually performed 9-rod Swedish tests with
5) 9-rod GE-CHF experiments.
The comparison with these data shows that WOSUB is capable of
predicting the lower-than-average behavior of the corner sub-
channel and the higher-than-average behavior of the center
subchannel for both quality and mass flux. None of the other
well-known subchannel codes is indeed capable of specifically
predicting the correct corner subchannel behavior. These codes
seem to inherently suffer from major deficiencies associated
with their incorporated mixing models. Therefore...
In this paper we present a systematic review of various home energy
management (HEM) schemes. Employment of home energy management programs will
make the electricity consumption smarter and more efficient. Advantages of HEM
include, increased savings for consumers as well as utilities, reduced peak to
average ratio (PAR) and peak demand. Where there are numerous applications of
smart grid technologies, home energy management is probably the most important
one to be addressed. Utilities across the globe have taken various steps for
efficient consumption of electricity. New pricing schemes like, Real Time
Pricing (RTP), Time of Use (ToU), Inclining Block Rates (IBR), Critical Peak
Pricing (CPP) etc, have been proposed for smart grid. Distributed Energy
Resources (DER) (local generation) and/or home appliances coordination along
with different tariff schemes lead towards efficient consumption of
electricity. This work also discusses a HEM systems general architecture and
various challenges in implementation of this architecture in smart grid.; Comment: IEEE 8th International Conference on Broadband and Wireless
Computing, Communication and Applications (BWCCA'13), Compiegne, France
In the Catani-Ciafaloni-Hautmann high-energy factorization approach a cross
section is expressed as a convolution of unintegrated gluon densities and a
gauge-invariant hard process, in which two incoming gluons are off-shell with
momenta satisfying certain high-energy kinematics. We present two methods of
evaluating the tree-level hard process with multiple final states. The first
one assumes that only one of the gluons is off-shell and relies on the
Slavnov-Taylor identities. Such asymmetric configuration of incoming gluons is
phenomenologically important in small x probing by forward processes. The
second method deals also with two off-shell gluons and is based on the analytic
continuation of the off-shell gluons momenta to the complex space. The methods
were implemented into Monte Carlo computer programs and used in
phenomenological applications. The results of both methods are
straightforwardly related to Lipatov's effective vertices in quasi-multi-regge
kinematics.; Comment: Presented at the Low x workshop, May 30 - June 4 2013, Rehovot and
There has been a significant increase in leakage energy dissipation of CMOS
circuits with each technology generation. Further, due to their large size,
last level caches (LLCs) spend a large fraction of their energy in the form of
leakage energy and hence, addressing this has become extremely important to
meet the challenges of chip power budget. For addressing this, several
techniques have been proposed. However, most of these techniques require
offline profiling and hence cannot be used for real-life systems which usually
run multitasking programs, with possible pre-emptions. In this paper, we
propose a dynamic profiling based technique for saving cache leakage energy in
multitasking systems. Our technique uses a small coloring-based profiling
cache, to estimate performance and energy consumption of multiple cache
configurations and then selects the best (least-energy) configuration among
them. Our technique uses non-intrusive profiling and saves energy despite
intra-task and inter-task variations; thus, it is suitable for multitasking
systems. Simulations performed using workloads from SPEC2006 suite show the
superiority of our technique over an existing cache energy saving technique.
With a 2MB baseline cache, the average saving in memory sub-system energy is
22.8%.; Comment: Cache leakage energy saving technique
This paper presents and justifies an open benchmark suite named BEEBS,
targeted at evaluating the energy consumption of embedded processors.
We explore the possible sources of energy consumption, then select individual
benchmarks from contemporary suites to cover these areas. Version one of BEEBS
is presented here and contains 10 benchmarks that cover a wide range of typical
embedded applications. The benchmark suite is portable across diverse
architectures and is freely available.
The benchmark suite is extensively evaluated, and the properties of its
constituent programs are analysed. Using real hardware platforms we show case
examples which illustrate the difference in power dissipation between three
processor architectures and their related ISAs. We observe significant
differences in the average instruction dissipation between the architectures of
4.4x, specifically 170uW/MHz (ARM Cortex-M0), 65uW/MHz (Adapteva Epiphany) and
88uW/MHz (XMOS XS1-L1).
In this paper, we present two symbiotic optimizations to optimize recursive
task parallel (RTP) programs by reducing the task creation and termination
overheads. Our first optimization Aggressive Finish-Elimination (AFE) helps
reduce the redundant join operations to a large extent. The second optimization
Dynamic Load-Balanced loop Chunking (DLBC) extends the prior work on loop
chunking to decide on the number of parallel tasks based on the number of
available worker threads, at runtime. Further, we discuss the impact of
exceptions on our optimizations and extend them to handle RTP programs that may
throw exceptions. We implemented DCAFE (= DLBC+AFE) in the X10v2.3 compiler and
tested it over a set of benchmark kernels on two different hardwares (a 16-core
Intel system and a 64-core AMD system). With respect to the base X10 compiler
extended with loop-chunking of Nandivada et al [Nandivada et
al.(2013)Nandivada, Shirako, Zhao, and Sarkar](LC), DCAFE achieved a geometric
mean speed up of 5.75x and 4.16x on the Intel and AMD system, respectively. We
also present an evaluation with respect to the energy consumption on the Intel
system and show that on average, compared to the LC versions, the DCAFE
versions consume 71.2% less energy.
ASIPs are designed in order to execute instructions of a particular domain of
applications. The designing of ASIPs addresses the major challenges faced by a
system on chip such as size, cost, performance and energy consumption. The
higher the number of similar instructions within the domain to be mapped the
lesser the energy consumption, the smaller the size and the higher the
performance of the ASIP. Thus, designing processors for domains with more
similar programs would overcome these issues. This paper describes the
investigation of whether the domains of programmer specific programs have any
significance like application specific program domains and thus, whether the
approach of designing processors known as Programmer Specific Instruction Set
Processors is worthwhile. We performed the evaluation at the instruction level
by using four different measures to obtain the similarity of programs: (1) by
the existence of each instruction, (2) by the frequency of each instruction,
(3) by two consecutive instruction patterns and (4) by three consecutive
instruction patterns of application specific and programmer specific programs.
We found that although programmer specific instructions show some impact on the
similarity measures, they are much smaller and therefore insignificant compared
to the impact from application specific programs.; Comment: The 7th International Conference on Information and Automation for
Sustainability (ICIAfS) 2014
We propose a unifying framework based on configuration linear programs and
randomized rounding, for different energy optimization problems in the dynamic
speed-scaling setting. We apply our framework to various scheduling and routing
problems in heterogeneous computing and networking environments. We first
consider the energy minimization problem of scheduling a set of jobs on a set
of parallel speed scalable processors in a fully heterogeneous setting. For
both the preemptive-non-migratory and the preemptive-migratory variants, our
approach allows us to obtain solutions of almost the same quality as for the
homogeneous environment. By exploiting the result for the
preemptive-non-migratory variant, we are able to improve the best known
approximation ratio for the single processor non-preemptive problem.
Furthermore, we show that our approach allows to obtain a constant-factor
approximation algorithm for the power-aware preemptive job shop scheduling
problem. Finally, we consider the min-power routing problem where we are given
a network modeled by an undirected graph and a set of uniform demands that have
to be routed on integral routes from their sources to their destinations so
that the energy consumption is minimized. We improve the best known
approximation ratio for this problem.; Comment: 27 pages
The utility company has many motivations for modifying energy consumption
patterns of consumers such as revenue decoupling and demand response programs.
We model the utility company--consumer interaction as a principal--agent
problem. We present an iterative algorithm for designing incentives while
estimating the consumer's utility function. Incentives are designed using the
aggregated as well as the disaggregated (device level) consumption data. We
simulate the iterative control (incentive design) and estimation (utility
learning and disaggregation) process for examples including the design of
incentives based on the aggregate consumption data as well as the disaggregated
Gao, Guang R.; The research proposed in this thesis will provide an analysis of these new scenarios, proposing new methodologies and solutions that leverage these new challenges in order to increase the performance and energy efficiency of modern many-core architectures. During the pursue of these objectives, this research intends to answer the following question: 1. Which is the impact of low-level compiler transformations such as tiling and percolation to effectively produce high performance code for many-core architectures? 2. What are the tradeoffs of static and dynamic scheduling techniques to efficiently schedule fine grain tasks with hundreds of threads sharing multiple resources under different conditions in a single chip? 3. Which hardware architecture features can contribute to better scalability and higher performance of scheduling techniques on many-core architectures on a single-chip? 4. How to effectively model high performance programs on many-core architectures under resource coordination conditions? 5. How to efficiently model energy consumption on many-cores managing tradeoffs between scalability and accuracy? 6. Which are feasible methodologies for designing power-aware tiling transformations on many-core architectures? (Abstract shortened by UMI.); University of Delaware...