1,720,956 research outputs found
A mixed-integer linear programming approach for the optimization of residential PV-battery energy storage system
Full text linkEurope ́s electricity sector is facing a major historical turning point shifting away from
fossil fuels towards more sustainable energy sources and moving from vertically
integrated public monopolies into competitive private companies in unbundled and
liberalized markets. In this scenario consumers are expected to play a fundamental role in
realising the full potential of the European energy market; the EU energy strategy, with
new policy and regulatory initiatives, in fact, recognizes consumers and communities as a
key driver of this process, encouraging them to take full ownership of the energy transition
and empowering them to actively participate in the electricity market by generating,
consuming and selling electricity back to the grid and interacting with other energy market
participants. Citizens are in fact no longer restricted to the role of passive end-use
consumers, but they are asked to be energy producers, or ‘prosumers’, representing an
important contribution to global sustainability and helping to decarbonize the electricity
sector. Furthermore, as well as allowing to increase the amount of renewable energy
generation, they have the potential to reduce the energy supply-demand gap and
electricity system losses and to provide opportunities for demand-side management and
for an active grid support increasing grid reliability flexibility, and resiliency. To this end,
distributed energy storage systems at the residential level have been identified as a priority
technology to open up new possibilities for local flexibility solutions and participation in
demand response, leading the energy transition towards new energy configurations, such
as self-generation and self-consumption schemes and peer-to-peer selling of the self
produced energy. Combining solar power generators and battery storage is one of the most
common ways of reaching self-sufficiency in residential buildings by increasing the grid
independence of individual households. Due to their cost and growth perspective, battery
storage coupled to photovoltaic (PV) generation systems have reached a good level of
competitiveness and market penetration in many European countries and they will
increase as more such systems become available. In this thesis a battery energy storage
systems (BESS) coupled with grid-connected rooftop-mounted residential photovoltaic generation is analyzed. The multi apartment building is located in Civitavecchia (Rome),
central Italy, with ten households living in rent at a subsidized price and it is covered by
the energy retrofit intervention and building renovation plan set by “Civitavecchia
SMART-A.T.E.R.” project aiming to convert the old buildings in new Near Zero Energy
Buildings (NZEBs) and to create energy communities. The aim of this thesis is to optimize
the sizing and the operation of the battery energy storage system so as to maximize the
households’ self-consumption and minimize their electricity bill, whilst ensuring the
correct charge-discharge cycles scheduling strategy in order to assure better performance
and a longer lifetime of the batteries. To this end, a multi-objective mixed-integer linear
programming (MILP) formulation is proposed and it is solved by CPLEX. The battery
sizing and operational parameters, in terms of number of batteries and
charging/discharging operation mode, are included in the optimization problem and a
penalty coefficient is imposed to limit the number of batteries needed. Collected and
estimated data of potential photovoltaic production and households’ demand profiles are
used to optimize the battery storage system using hourly dataset for different seasons
Multi-objective mathematical programming for optimally sizing and managing battery energy storage for solar photovoltaic system integration of a multi-apartment building
No full textThis article presents a novel mathematical formulation to solve the problem of optimally sizing and managing battery energy storage for the solar photovoltaic system integration of a multi-apartment building. The aim is the maximization of the collective self-consumption maintaining control over time of the energy sold and bought and the monitoring of the state of batteries while ranging from minimum to maximum levels. This is obtained through a new mathematical programming model with three different objective functions that can be tuned simultaneously to find Pareto optimal solutions to the problem. The computational results in detailed scenarios with real data verify the model's adequacy to deal with the real problem and give a measure of the saving of bought and sold energy
Multivariate KPI for energy management of cooling system in food industry
Full text linkWithin EU, the food industry is currently ranked among the energy-intensive sectors, mainly as a consequence of the cooling
system shareover the total energy demand.
As such, the definition of appropriate key performance indicators (KPI) for ammonia chillers can play a strategic role for the
efficient monitoring of the energy performance of the cooling systems.
The goal of this paper is to develop an appropriate management approach, to account for energy inefficiency of the single
compressors, and to identify the specific variables driving the performance outliers.
To this end, a new KPI is proposed which correlates the energy consumption and the different process variables. The construction
of the new indicator was carried out by means of multivariate statistical analysis, in particular using Kernel Partial Least Square
(KPLS).This method is able to evaluate the maximum correlation between dataset and energy consumption employing nonlinear
regression techniques.
The validity of the new KPI is discussed on a case study relevant to the cooling system of a frozen ready meals industry. The
assessment of the proposed metric is one against Specific Energy Consumption (SEC) like indicator, typically used in the context
of the Energy Management Systems
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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