4,740 research outputs found

    Incremental learning with respect to new incoming input attributes

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    Neural networks are generally exposed to a dynamic environment where the training patterns or the input attributes (features) will likely be introduced into the current domain incrementally. This paper considers the situation where a new set of input attributes must be considered and added into the existing neural network. The conventional method is to discard the existing network and redesign one from scratch. This approach wastes the old knowledge and the previous effort. In order to reduce computational time, improve generalization accuracy, and enhance intelligence of the learned models, we present ILIA algorithms (namely ILIA1, ILIA2, ILIA3, ILIA4 and ILIA5) capable of Incremental Learning in terms of Input Attributes. Using the ILIA algorithms, when new input attributes are introduced into the original problem, the existing neural network can be retained and a new sub-network is constructed and trained incrementally. The new sub-network and the old one are merged later to form a new network for the changed problem. In addition, ILIA algorithms have the ability to decide whether the new incoming input attributes are relevant to the output and consistent with the existing input attributes or not and suggest to accept or reject them. Experimental results show that the ILIA algorithms are efficient and effective both for the classification and regression problems

    Parallel growing and training of neural networks using output parallelism

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    In order to find an appropriate architecture for a large-scale real-world application automatically and efficiently, a natural method is to divide the original problem into a set of sub-problems. In this paper, we propose a simple neural network task decomposition method based on output parallelism. By using this method, a problem can be divided flexibly into several sub-problems as chosen, each of which is composed of the whole input vector and a fraction of the output vector. Each module (for one sub-problem) is responsible for producing a fraction of the output vector of the original problem. The hidden structure for the original problem’s output units are decoupled. These modules can be grown and trained in parallel on parallel processing elements. Incorporated with a constructive learning algorithm, our method does not require excessive computation and any prior knowledge concerning decomposition. The feasibility of output parallelism is analyzed and proved. Some benchmarks are implemented to test the validity of this method. Their results show that this method can reduce computational time, increase learning speed and improve generalization accuracy for both classification and regression problems

    A design for investigating the association of birth weight, weight change during life course with adult hypertension in Hong Kong women

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    Poster Presentation: P-6A-270"Fetal origins hypothesis" by Barker in 1990 is a well known hypothesis. One of the key finding was that low birth weight was associated with higher adult systolic blood pressure. However, in 2002, Huxley et al argued that birth weight had little relevance in determining blood pressure levels in later life. But after that, several studies argued against it until now. In addition, some experts think that change in size between birth and current rather than fetal biology itself affect the blood pressure, which means the fetal origins hypothesis must be weighed against a "postnatal origins hypothesis". Therefore, it is important to explore what is the interaction between later body weight change and fetal programming on the effect of BP ...published_or_final_versio

    Lutembacher's syndrome: A rare combination of congenital and acquired heart disease – A case report and review of literature

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    Lutembacher's syndrome is defined as the rare combination of congenital atrial septal defect and acquired mitral stenosis. The haemodynamic effects of this syndrome are a result of the interplay between the relative effects of the atrial septal defect and mitral stenosis. Mitral stenosis augments the left to right shunt through the atrial septal defect. The definition of Lutembacher's syndrome has undergone many changes. The earliest description in medical literature was found in a letter written by anatomist Johann Friedrich Meckel to Albrecht von Haller in 1750.In 1916, Lutembacher described his first case of this syndrome, involving a 61-year-old woman, and he attributed the mitral valvular lesion to congenital mitral stenosis. Because the mitral stenosis was, in fact, rheumatic in aetiology, the syndrome was defined eventually as a combination of congenital atrial septal defect and acquired, almost always rheumatic, mitral stenosis.Keywords:Lutembacher's syndrome, congenital heart disease, valvular heart disease,  atrial septal defect, mitral stenosi

    Laboratory Evaluation of Flurox, a Chitin Synthesis Inhibitor, on the Termite, Microcerotermes diversus

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    Microcerotermes diversus (Silvestri) (Isoptera: Termitidae) is the most economically destructive termite in structures in southwest Iran. One sustainable control strategy that usually helps to reduce subterranean termite damage in buildings, is the use of insect growth regualtors in a suitable bait matrix that are safe to the user and the environment. In the laboratory assays described here, the delayed toxicity of Flurox, a chitin synthesis inhibitor, to M. diversus was evaluated under force-feeding and choice trials. Flurox induced worker and nymph mortality and incomplete ecdysis in nymphs of M. diversus under no-choice and two-choice feeding tests. These adverse effects may cause disruption of the caste balance in M. diversus, leading to the collapse of the colony. These assays determined concentrations of Flurox that can be used in bait formulations

    Ultraviolet Lasing Characteristics of ZnS Microbelt Lasers

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    Post-growth annealing induced change of conductivity in As-doped ZnO grown by radio frequency magnetron sputtering

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    Arsenic-doped ZnO films were fabricated by radio frequency magnetron sputtering method at a relatively low substrate temperature of 200 C. Post-growth annealing in air was carried out up to a temperature of 1000 C. The samples were characterized by Hall measurement, positron annihilation spectroscopy (PAS), secondary ion mass spectroscopy (SIMS), and cathodoluminescence (CL). The as-grown sample was of n-type and it converted to p-type material after the 400 C annealing. The resulting hole concentration was found to increase with annealing temperature and reached a maximum of 6 10 17cm -3 at the annealing temperature of 600 C. The origin of the p-type conductivity was consistent with the As Zn(V Zn) 2 shallow acceptor model. Further increasing the annealing temperature would decrease the hole concentration of the samples finally converted the sample back to n-type. With evidence, it was suggested that the removal of the p-type conductivity was due to the dissociation of the As Zn(V Zn) 2 acceptor and the creation of the deep level defect giving rise to the green luminescence. © 2011 American Institute of Physics.published_or_final_versio

    Leg disorders in broiler chickens : prevalence, risk factors and prevention

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    Broiler (meat) chickens have been subjected to intense genetic selection. In the past 50 years, broiler growth rates have increased by over 300% (from 25 g per day to 100 g per day). There is growing societal concern that many broiler chickens have impaired locomotion or are even unable to walk. Here we present the results of a comprehensive survey of commercial flocks which quantifies the risk factors for poor locomotion in broiler chickens.We assessed the walking ability of 51,000 birds, representing 4.8 million birds within 176 flocks.We also obtained information on approximately 150 different management factors associated with each flock. At a mean age of 40 days, over 27.6% of birds in our study showed poor locomotion and 3.3% were almost unable to walk. The high prevalence of poor locomotion occurred despite culling policies designed to remove severely lame birds from flocks. We show that the primary risk factors associated with impaired locomotion and poor leg health are those specifically associated with rate of growth. Factors significantly associated with high gait score included the age of the bird (older birds), visit (second visit to same flock), bird genotype, not feeding whole wheat, a shorter dark period during the day, higher stocking density at the time of assessment, no use of antibiotic, and the use of intact feed pellets. The welfare implications are profound. Worldwide approximately 261010 broilers are reared within similar husbandry systems.We identify a range of management factors that could be altered to reduce leg health problems, but implementation of these changes would be likely to reduce growth rate and production. A debate on the sustainability of current practice in the production of this important food source is required
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