149 research outputs found

    Dimensionement optimal des systèmes énergétiques intégrant la stratégie de gestion pour une maison raccordée au réseau

    No full text
    International audienceCet article présente une méthodologie de dimensionnement optimal intégrant la stratégie de gestion d'un système d'énergie complexe (chauffage, climatisation, PV et stockage électrochimique) pour un bâtiment raccordé au réseau. Le confort thermique, déterminé grâce à un modèle d'enveloppe thermique dynamique d'ordre réduit, et le coût sur le cycle de vie seront pris en compte comme les critères d'optimisation alors que la couverture de la charge sera considérée comme une des contraintes. Cela se traduit par la formulation d'un problème d'optimisation multi-objectif complexe avec un grand nombre de paramètres et de contraintes, mais on va montrer qu'il peut être calculé rapidement en utilisant une approche d'optimisation de type gradient. Le cas d'étude est une maison individuelle située au Sud-Est de la France. Les résultats d'optimisation que nous obtenons sont les meilleurs compromis entre confort et coût global (fabrication et utilisation).

    Les enjeux de la conception en phase d'esquisse pour les systèmes du génie électrique : illustration sur le cas des systèmes énergétiques pour les bâtiments

    No full text
    International audienceCe papier propose de donner un statut, et un outil, aux phases de conception initiale, dans lesquelles les caractéristiques principales du système énergétique utilisant l'énergie électrique doivent être esquissées. Nous proposons ainsi, d'utiliser un type de modèle adapté (modèle macroscopique et statique basé sur des bilans énergétiques et financiers). Ces modèles sont réalisés à l'échelle des composants du système et ils comportent des équations et des contraintes, qui sont ensuite composées à l'échelle du système, via des ports énergétiques et financiers. Il en résulte un modèle qui peut dès lors, être utilisé par des techniques d'optimisation. Cela permet de fournir un dimensionnement global et simultané des caractéristiques du système (taille et dimension des systèmes énergétiques) tout en esquissant une stratégie de gestion optimale sur des cycles de fonctionnement type. La fonction objectif est un coût global du système intégrant les coûts d'investissement, de maintenance et d'exploitation. Cette approche est illustrée sur un exemple de gare, représentatif à la fois des enjeux de la filière bâtiment, mais aussi représentatif de cette problématique de conception générique des systèmes hybrides comportant des sources, des charges et des moyens de stockage, auquel le génie électrique est de plus en plus confronté via des application dans les transports terrestres, aéronautiques, le smart-building, le smart-grid, ..

    Les enjeux de la conception système en phase d'esquisse pour les systèmes du génie électrique : illustration sur le cas des systèmes énergétiques pour les bâtiments

    No full text
    Ce papier propose de donner un statut, et un outil, aux phases de conception initiale, dans lesquelles les caractéristiques principales du système énergétique utilisant l'énergie électrique doivent être esquissées. Nous proposons ainsi, d'utiliser un type de modèle adapté (modèle macroscopique et statique basé sur des bilans énergétiques et financiers). Ces modèles sont réalisés à l'échelle des composants du système et ils comportent des équations et des contraintes, qui sont ensuite composées à l'échelle du système, via des ports énergétiques et financiers. Il en résulte un modèle qui peut dès lors, être utilisé par des techniques d'optimisation. Cela permet de fournir un dimensionnement global et simultané des caractéristiques du système (taille et dimension des systèmes énergétiques) tout en esquissant une stratégie de gestion optimale sur des cycles de fonctionnement type. La fonction objectif est un coût global du système intégrant les coûts d'investissement, de maintenance et d'exploitation. Cette approche est illustrée sur un exemple de gare, représentatif à la fois des enjeux de la filière bâtiment, mais aussi représentatif de cette problématique de conception générique des systèmes hybrides comportant des sources, des charges et des moyens de stockage, auquel le génie électrique est de plus en plus confronté via des application dans les transports terrestres, aéronautiques, le smart-building, le smart-grid, ..

    Effects of Crossbreeding and Feed Supplementation on Meat Productivity of Goats in Laos: 2. Body Composition and Meat Quality

    Full text link
    A 5 month long 2x2 factorial feeding trial was carried out to determine effects of crossbreeding and feed supplementation on meat productivity of goats in Laos. The indigenous goat breed (Lat) was used as the control to compare with the F1 (BT x L) as a result of crossbreeding Lat does with bucks of Bach Thao, an improved goat breed imported from Vietnam. For each genotype, 30 growing male goats at 7 months of age were chosen and equally divided into 2 groups, each being raised under either the traditional feeding regime (free grazing only) or an improved feeding regime including dried cassava hay and mineral block provided ad libitum in addition to the free grazing regime. Observations included feed intake, live weight gain, dressing percentage, body composition, carcass parts, and meat quality. This paper presents body composition and meat quality of the goats as affected by crossbreeding and feed supplementation. Results showed that although there existed significant differences in weight percentage of some organs (legs, lungs and liver) in the body, no significant diferences were observed for meat quality (tenderness, color, pH, drip loss and cooking loss) between Lat and F1 goats under the two different feeding regimes. It was therefore concluded that crossbreeding with Bach Thao bucks imported from Vietnam and feed supplementation (cassava hay and mineral block) well improved meat yield without negative effects on meat quality of goats in Laos.Peer reviewe

    Quality of Water used at pig farms in the Red River delta

    Full text link
    peer reviewedA research was carried out to evaluate water quality using at 12 different pig farms in Bac Ninh, Hung Yen and Hai Duong provinces. Water samples were taken in two periods from October to December 2006 and from March to April 2007. Physical and chemical parameters were analysed at the laboratory of the Department of Veterinary Parasitology-Inspection and Hygiene - Hanoi University of Agriculture. The results showed that, all water sources using the pig farms came from underground and a half of which was not processed. Contents of COD(H+), COD(OH-), CO2, Cl- in water in Hai Duong and Bac Ninh were exceeded the hygiene standard. Iron content in water in all three provinces was exceeded the hygiene standard. After using a processed system including artificial rain, H2O2 supplement and filter the content of DO, CO2 and Fe in the water reached the permitted hygiene standard

    1M parameters are enough? A lightweight CNN-based model for medical image segmentation

    Full text link
    Convolutional neural networks (CNNs) and Transformer-based models are being widely applied in medical image segmentation thanks to their ability to extract high-level features and capture important aspects of the image. However, there is often a trade-off between the need for high accuracy and the desire for low computational cost. A model with higher parameters can theoretically achieve better performance but also result in more computational complexity and higher memory usage, and thus is not practical to implement. In this paper, we look for a lightweight U-Net-based model which can remain the same or even achieve better performance, namely U-Lite. We design U-Lite based on the principle of Depthwise Separable Convolution so that the model can both leverage the strength of CNNs and reduce a remarkable number of computing parameters. Specifically, we propose Axial Depthwise Convolutions with kernels 7x7 in both the encoder and decoder to enlarge the model receptive field. To further improve the performance, we use several Axial Dilated Depthwise Convolutions with filters 3x3 for the bottleneck as one of our branches. Overall, U-Lite contains only 878K parameters, 35 times less than the traditional U-Net, and much more times less than other modern Transformer-based models. The proposed model cuts down a large amount of computational complexity while attaining an impressive performance on medical segmentation tasks compared to other state-of-the-art architectures. The code will be available at: https://github.com/duong-db/U-Lite.Comment: 6 pages, 7 figure

    Some issues of geomorphology to serve coastal environmental management of Quang Nam province

    Get PDF
    This paper presents the results of studies on the coastal geomorphological processes, which have been happening, to serve the coastal environmental management of Quang Nam province. Research results show that the geomorphological process is mainly destruction or coastal erosion, which has been occurring in most of the shores formed by loose material. In particular, coastal erosion has occurred strongly on the beaches of Cua Dai ward (Hoi An), in the south of Cua Dai (Duy Xuyen) and the south of Cua Lo (Nui Thanh). On the other hand, using geomorphological research methods, in the study area, we have determined five different geomorphic units belonging to the nearshore seabed. Thus, the zonation is carried out for risk warning according to different levels of risk of geomorphological hazards. This can help managers get a general picture for planning as well as have a specific planning policy for each coastal region in the coastal strip of Quang Nam province

    ffect of the Halothane Allele on Growth Performance of Pigs and its Genotype Frequencies in the Progeny

    Full text link
    A total of 395 tail samples of stress negative Piétrain new born piglets from the pig farm of Dong Hiep Haiphong were used to determine halothane genotypes (CC, CT and TT) in order to study the effect of mating type (♂CC×♀CC, ♂CC×♀CT, ♂CT×♀CC, and ♂CT×♀CT) on halothane genotype frequencies. Effects of genotype on live weight (174 pigs of 2 month old, 96 pigs of 5.5 month old), back fat thickness, loin muscle thickness and lean percentage (117 pigs), average daily gain (89 pigs) were also studied. Results showed that the mating type affected halothane genotype frequencies in the progeny. For the mating type ♂CC×♀CT and ♂CT×♀CT, the genotype containing allele T was reduced in the next generation; in the rest two genotypes (♂CC×♀CC and ♂CT×♀CC) the halothane allele frequency in the offspring was consistent with the theoretical frequency. The halothane genotypes CC and CT did not affect live weights at 2.0 and 5.5 months of age, average daily gain, backfat thickness, loin muscle thickness and lean percentage.Peer reviewe

    Characterization of pig farms in Hung Yen, Hai Duong and Bac Ninh provinces

    Full text link
    peer reviewedIn order to characterization of pig farms in the Red River Delta, a study was conducted on 90 pig farms in Hung Yen, Hai Duong and Bac Ninh provinces from June to December 2006. Results show that most of the pig farms had been built for five years with a small size (0.5 hectare per farm). The invested capital was about 300-400 millions VND per farm. Four main sow groups used in the farms included crossbred exotic sows (51.1%), crossbred sow between local and exotic breeds (14.4%), purebred Landrace and Yorkshire breeds (15.6 and 18.9%, respectively). The boars were various (Duroc 30%, Yorkshire 21%, Landrace 13%, PiÐtrain × Duroc 36% and others). The pigs farms were faced with several difficulties such as limited land, lack of invested capital, uncontrolled quality of breeding pigs, high costs of feed, poor hygiene condition and diseases
    corecore