20 research outputs found
Deriving item features relevance from collaborative domain knowledge
An Item based recommender system works by computing a similarity between
items, which can exploit past user interactions (collaborative filtering) or
item features (content based filtering). Collaborative algorithms have been
proven to achieve better recommendation quality then content based algorithms
in a variety of scenarios, being more effective in modeling user behaviour.
However, they can not be applied when items have no interactions at all, i.e.
cold start items. Content based algorithms, which are applicable to cold start
items, often require a lot of feature engineering in order to generate useful
recommendations. This issue is specifically relevant as the content descriptors
become large and heterogeneous. The focus of this paper is on how to use a
collaborative models domain-specific knowledge to build a wrapper feature
weighting method which embeds collaborative knowledge in a content based
algorithm. We present a comparative study for different state of the art
algorithms and present a more general model. This machine learning approach to
feature weighting shows promising results and high flexibility
Deep learning for time series forecasting: The electric load case
Management and efficient operations in critical infrastructures such as smart grids take huge advantage of accurate power load forecasting, which, due to its non-linear nature, remains a challenging task. Recently, deep learning has emerged in the machine learning field achieving impressive performance in a vast range of tasks, from image classification to machine translation. Applications of deep learning models to the electric load forecasting problem are gaining interest among researchers as well as the industry, but a comprehensive and sound comparison among different-also traditional-architectures is not yet available in the literature. This work aims at filling the gap by reviewing and experimentally evaluating four real world datasets on the most recent trends in electric load forecasting, by contrasting deep learning architectures on short-term forecast (one-day-ahead prediction). Specifically, the focus is on feedforward and recurrent neural networks, sequence-to-sequence models and temporal convolutional neural networks along with architectural variants, which are known in the signal processing community but are novel to the load forecasting one
INFLUENCE OF SUBSTRATE AND CONTAINER VOLUME ON THE QUALITY OF Cabralea canjerana (Vell.) Mart. SEEDLINGS IN NURSERY AND FIELD
A utiliza\ue7\ue3o de mudas de qualidade \ue9 fundamental para o
estabelecimento de plantios florestais, o que \ue9 alcan\ue7ado por
meio de t\ue9cnicas adequadas desde a fase de viveiro. Assim, este
trabalho teve por objetivo investigar a influ\ueancia de diferentes
composi\ue7\uf5es de substratos e do volume de recipiente (tubetes)
no crescimento de mudas de canjerana ( Cabralea canjerana ), no
viveiro e no campo. Em viveiro foram avaliadas tr\ueas
composi\ue7\uf5es de substratos \ue0 base de turfa (100% turfa,
turfa + 20% casca de arroz carbonizada (CAC) e turfa + 40% CAC)
combinadas com dois tamanhos de tubetes (100 e 280 cm3). Foram
realizadas mensalmente, durante 330 dias, mensura\ue7\uf5es do
di\ue2metro do coleto (DC) e da altura (H), e foi calculada
tamb\ue9m a rela\ue7\ue3o H/DC. Aos 330 dias foram avaliadas as
massas secas radicular, a\ue9rea e total e o \uedndice de qualidade
de Dickson. Os mesmos tratamentos foram avaliados em campo, durante um
per\uedodo de 360 dias, e foi mensurado a cada 90 dias, o DC e a H, e
calculada a H/DC. No viveiro e em campo, os experimentos foram
conduzidos com delineamento experimental de blocos ao acaso, com quatro
repeti\ue7\uf5es. Mudas de canjerana podem ser produzidas em
substrato composto por 60% de turfa e 40% de casca de arroz carbonizada
sem preju\uedzo do seu crescimento em campo, tendo em vista a
economia que representa no viveiro. O uso do tubete de 280 cm3
proporcionou somente crescimento superior das mudas na fase de plantio,
sendo que o di\ue2metro do coleto e a massa seca radicular
expressaram o melhor desempenho.The use of quality seedlings is essential for the establishment of
forest plantations, which is achieved through the use of appropriate
techniques from the nursery. Thus, this study aimed to investigate the
influence of substrate composition and volume of container (tubes) in
the growth of seedlings of canjerana ( Cabralea canjerana ), in the
nursery and field. In nursery, three compositions of peat substrates
were evaluated (100% peat, peat + 20% rice hulls (RH) and peat + 40%
RH) and combined with two sizes of containers (100 and 280 cm3).
Measurements of root collar diameter (DC) and height (H) were performed
monthly during 330 days, and the ratio H/DC was also calculated. At 330
days, the root, air and total dry masses and Dickson\u2019s quality
index were assessed. The same treatments were evaluated in the field
during a period of 360 days and DC and H were measured and H/DC was
calculated in every 90-day period. In the nursery and field experiments
were carried out with experimental design of random blocks, with four
replications. Seedlings of canjerana can be produced in a substrate
composed of 60% peat and 40% of rice hulls without harming its growth
in the field, with a view that the economy is in nursery. The tube of
the tube in the size 280 cm3 only provided superior growth of seedlings
during the field phase, where seedlings produced in these containers
expressed a better performance in relation to root collar diameter and
root dry mass
ENSEÑANZA DE ENFERMERÍA: ¿QUIÉN DISCUTE Y LO QUÉ ES DISCUTIDO?
O presente trabalho teve por objetivo descrever de que forma o Ensino de Enfermagem vem sendo discutido e o perfil dos autores que discutem esse tema. A pesquisa de revisão sistemática foi operacionalizada por meio da busca eletrônica de artigos indexados na base de dados SciELO, por meio do descritor “Ensino de Enfermagem”, em “Assunto”, no dia 15 de abril de 2010. Foram analisados todos os artigos encontrados, perfazendo um universo de 11 trabalhos. Os resultados sugerem que a pesquisa científica na área do Ensino de Enfermagem ainda é pouco desenvolvida e que os autores dos artigos analisados possuem formação acadêmica adequada à reflexão neste tema. O principal foco dos estudos são as mudanças sofridas ou, em alguns estudos, a necessidade de mudanças no Ensino de Enfermagem para atender ao contexto econômico, político e social e as evoluções das políticas públicas de saúde ao longo do tempo.This work aims to describe the way in which Nursing Teaching is being discussed and the profile of the authors who discuss it. The literature search was undertaken via the Internet, searching for articles indexed in the SciELO database, with the search term ‘Nurse Teaching’ as subject, on April 15th 2010. All 11 articles found were analyzed. The results suggest that scientific research in the area of Nurse Teaching is under-developed but that the authors of the articles analyzed possess appropriate academic backgrounds for reflecting on the subject. The main focus of the studies is the changes which have happened, and, in some studies, the necessity for changes to keep up with the economic, political and social context and changes in public health policy over time.El presente trabajo tuvo por objetivo describir de que modo la Enseñanza de Enfermería está siendo discutida y el perfil de los autores que discuten ese tema. La investigación de revisión sistemática fue operacionalizada por medio de la búsqueda electrónica de artículos indexados en la base de datos SciELO, por medio del descriptor “Enseñanza de Enfermería”, en “Asunto”, el día 15 de abril de 2010. Fueron analizados todos los artículos encontrados, tolalizando un universo de 11 trabajos. Los resultados sugieren que la investigación científica en área de Enseñanza de Enfermería todavía es poco desarrollada y que los autores de los artículos analizados poseen formación académica adecuada a la reflexión neste tema. El principal foco de los estudios son las cambios sufridas o, en algunos estudios, la necesidad de cambios en la Enseñanza de Enfermería para atender al contexto económico, político y social y las evoluciones de las políticas públicas de salud a lo largo del tiempo
Potency of descending pain modulatory system is linked with peripheral sensory dysfunction in fibromyalgia : An exploratory study
Fibromyalgia (FM) is characterized by chronic widespread pain whose pathophysiological mechanism is related to central and peripheral nervous system dysfunction. Neuropathy of small nerve fibers has been implicated due to related pain descriptors, psychophysical pain, and neurophysiological testing, as well as skin biopsy studies. Nevertheless, this alteration alone has not been previously associated to the dysfunction in the descending pain modulatory system (DPMS) that is observed in FM. We hypothesize that they associated, thus, we conducted a cross-sectional exploratory study. To explore small fiber dysfunction using quantitative sensory testing (QST) is associated with the DPMS and other surrogates of nociceptive pathways alterations in FM. We run a cross-sectional study and recruited 41 women with FM, and 28 healthy female volunteers. We used the QST to measure the thermal heat threshold (HTT), heat pain threshold (HPT), heat pain tolerance (HPT), heat pain tolerance (HPTo), and conditional pain modulation task (CPM-task). Algometry was used to determine the pain pressure threshold (PPT). Scales to assess catastrophizing, anxiety, depression, and sleep disturbances were also applied. Serum brain-derived neurotrophic factor (BDNF) was measured as a marker of neuroplasticity. We run multivariate linear regression models by group to study their relationships. Samples differed in their psychophysical profile, where FM presented lower sensitivity and pain thresholds. In FM but not in the healthy subjects, regression models revealed that serum BDNF was related to HTT and CPM-Task (Hotelling Trace=1.80, P<.001, power=0.94, R2=0.64). HTT was directly related to CPM-Task (B=0.98, P=.004, partial-n2=0.25), and to HPT (B=1.61, P=.008, partial n2=0.21), but not to PPT. Meanwhile, BDNF relationship to CPM-Task was inverse (B=–0.04, P=.043, partial-n2=0.12), and to HPT was direct (B=–0.08, P=.03, partial-n2=0.14). These findings high spot that in FM the disinhibition of the DPMS is positively correlated with the dysfunction in peripheral sensory neurons assessed by QST and conversely with serum BDNF. Abbreviations: ACR = American College of Rheumatology, BDI-II = Beck Depression Inventory, BDNF = brain-derived neurotrophic factor, BP-PCS = Brazilian Portuguese Catastrophizing Scale, CPM-task = conditional pain modulation task, DPMS = descending pain modulatory system, ELISA = Enzyme-Linked Immunosorbent Assay, FIQ = Fibromyalgia Impact Questionnaire, FM = Fibromyalgia, HCPA = Hospital de Clinicas de Porto Alegre, HPT = heat pain threshold, HPTO = heat pain tolerance, HTT = thermal heat threshold, LTD = long term depression, NGF = neural growth factor, NMDA = N-methyl-D-aspartate, NPS = numerical pain scale, NRM = nucleus raphe magnus, PKC = Protein kinase C, PPT = pain pressure threshold, PSQI = Pittsburgh Sleep Quality Index, QST = quantitative sensory testing, STAI = State-Trait Anxiety Inventory, STT = spinothalamic tract, tDCS = transcranial direct
Environmental restriction or an opportunity for sustainable development? The Karst Aquifer in the metropolitan region of Curitiba
Em termos ambientais, a expansão de áreas urbanas tornou-se um problema mais grave do que o crescimento demográfico em si. Para fazer frente a esse desafio, a Organização para a Cooperação e Desenvolvimento Econômico (OCDE) indica a necessidade de mudanças na gestão das cidades, com a adoção de estratégias participativas de intervenção como forma de reduzir os conflitos socioambientais e diminuir o efeito da poluição sobre o meio natural. Este artigo tem como pano de fundo a formulação de políticas para a ocupação de áreasde mananciais em contextos urbanos, tomando como estudo de caso a percepção da população residente e dos representantes das instituições de governo sobre a conservação de mananciais subterrâneos de formação cárstica na Região Metropolitana de Curitiba.In environmental terms, the expansion of urban areas has become a problem that is more serious than that of population growth itself. To face this challenge, the Organization for Economic Cooperation and Development (OECD) indicates the need for changes in city management with the adoption of participative intervention as a strategy to reduce socio-environmental conflicts and control the effects of pollution on the natural environment. The background of this paper is the formulation of watershed occupation policies in urban contexts. The paper studies the perception of residents and representatives of government institutions about the conservation of karst groundwater in the Metropolitan Region of Curitiba
Dimensionamento Amostral para Avaliação de Altura e Diâmetro de Plantas de Timbaúva
RESUMO O objetivo do estudo foi estimar o tamanho de amostra para avaliar a altura de planta (H), o diâmetro do coleto (D) e a relação altura de planta/diâmetro do coleto (HD) de timbaúva (Enterolobium contortisiliquum) e verificar a variabilidade do tamanho de amostra entre tubetes, doses de fertilizante e idades de avaliação. Foram avaliados dez tratamentos, formados pela combinação de tamanhos de tubetes (110 e 180 cm3) e doses de fertilizante (0, 3, 5, 7 e 9 g L-1 de substrato), no delineamento em blocos, com quatro repetições. Em cinco idades foram determinadas H, D e HD. O tamanho de amostra para H, D e HD é dependente da idade de avaliação. Para os tamanhos de tubetes, doses de fertilizante e idades de avaliação, 22 plantas por unidade experimental (bandeja) são suficientes para estimar a média dessas características, para erro de estimação de 10% da média, com grau de confiança de 95%