238 research outputs found
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Chaotic behavior control in fluidized bed systems using artificial neural network. Quarterly progress report, October 1, 1996--December 31, 1996
Pressurized fluidized-bed combustors (FBC) are becoming very popular, efficient, and environmentally acceptable replica for conventional boilers in Coal-fired and chemical plants. In this paper, we present neural network-based methods for chaotic behavior monitoring and control in FBC systems, in addition to chaos analysis of FBC data, in order to localize chaotic modes in them. Both of the normal and abnormal mixing processes in FBC systems are known to undergo chaotic behavior. Even though, this type of behavior is not always undesirable, it is a challenge to most types of conventional control methods, due to its unpredictable nature. The performance, reliability, availability and operating cost of an FBC system will be significantly improved, if an appropriate control method is available to control its abnormal operation and switch it to normal when exists. Since this abnormal operation develops only at certain times due to a sequence of transient behavior, then an appropriate abnormal behavior monitoring method is also necessary. Those methods has to be fast enough for on-line operation, such that the control methods would be applied before the system reaches a non-return point in its transients. It was found that both normal and abnormal behavior of FBC systems are chaotic. However, the abnormal behavior has a higher order chaos. Hence, the appropriate control system should be capable of switching the system behavior from its high order chaos condition to low order chaos. It is to mention that most conventional chaos control methods are designed to switch a chaotic behavior to a periodic orbit. Since this is not the goal for the FBC case, further developments are needed. We propose neural network-based control methods which are known for their flexibility and capability to control both non-linear and chaotic systems. A special type of recurrent neural network, known as Dynamic System Imitator (DSI), will be used for the monitoring and control purposes
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Chaotic behavior control in fluidized bed systems using artificial neural network. Quarterly progress report, April 1, 1996--June 30, 1996
We have developed techniques to control the chaotic behavior in the Fluidized Bed (FBC) Systems using Artificial Neural Networks (ANNs). For those techniques to cross from theory to implementation, the computer programs we are developing have to be interfaced with the outside world, as a necessary step towards the actual interface with an FBC system or its experimental mock up. For this reason we are working on a Data Acquisition Board setup that will enable communication between our programs and external systems. Communication is planned to be enabled in both ways to deliver feedback signals from a system to the control programs in one way, and the control signals from the control programs to the controlled system in the other way. On the other hand, since most of our programs are PC based, they have to follow the revolutionary progress in the PC technology. Our programs were developed in the DOS environment using an early version of Microsoft C compiler. For those programs to meet the current needs of most PC users, we are working on converting those programs to the Windows environment, using a very advanced and up to date C++ compiler. This compiler is known as the Microsoft Visual C++ Version 4.0. This compiler enables the implementation of very professional and sophisticated Windows 95, 32 bit applications. It also allows a simple utilization of the Object Oriented Programming (OOP) techniques, and lots of powerful graphical and communication tools known as the Microsoft Foundation Classes (MFC). This compiler also allows creating Dynamic Link Libraries (DLLS) that can be liked together or with other Windows programs. These two main aspects, the computer-system interface and the DOS-Windows migration will give our programs a leap frog towards their real implementation
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Neural Network Based Montioring and Control of Fluidized Bed.
The goal of this project was to develop chaos analysis and neural network-based modeling techniques and apply them to the pressure-drop data obtained from the Fluid Bed Combustion (FBC) system (a small scale prototype model) located at the Federal Energy Technology Center (FETC)-Morgantown. The second goal was to develop neural network-based chaos control techniques and provide a suggestive prototype for possible real-time application to the FBC system. The experimental pressure data were collected from a cold FBC experimental set-up at the Morgantown Center. We have performed several analysis on these data in order to unveil their dynamical and chaotic characteristics. The phase-space attractors were constructed from the one dimensional time series data, using the time-delay embedding method, for both normal and abnormal conditions. Several identifying parameters were also computed from these attractors such as the correlation dimension, the Kolmogorov entropy, and the Lyapunov exponents. These chaotic attractor parameters can be used to discriminate between the normal and abnormal operating conditions of the FBC system. It was found that, the abnormal data has higher correlation dimension, larger Kolmogorov entropy and larger positive Lyapunov exponents as compared to the normal data. Chaotic system control using neural network based techniques were also investigated and compared to conventional chaotic system control techniques. Both types of chaotic system control techniques were applied to some typical chaotic systems such as the logistic, the Henon, and the Lorenz systems. A prototype model for real-time implementation of these techniques has been suggested to control the FBC system. These models can be implemented for real-time control in a next phase of the project after obtaining further measurements from the experimental model. After testing the control algorithms developed for the FBC model, the next step is to implement them on hardware and link them to the experimental system. In this report, the hardware implementation issues of the control algorithms are also discussed
Transient development of gravity waves for two layered fluids
The transient gravity waves generated by a harmonically oscillating wave maker immersed in two incompressible fluids, the upper fluid having a free surface, is considered. The resulting linearized initial value problem is solved using the method of generalized functions, and asymptotic analysis for large time and distance are given for the elevation
Possible protective and curative effects of selenium nanoparticles on testosterone-induced benign prostatic hyperplasia rat model
Background: Men over the age of 40 are more likely to develop benign prostatic hyperplasia (BPH). BPH is characterized by proliferation of the prostatic epithelium and stroma. Selenium nanoparticles (SeNPs), is an essential metalloid mineral and antioxidant. In this study, SeNPs were tested for their potential protective and curative impacts on BPH in rats.
Materials and methods: 50 male Sprague-Dawley rats were randomly divided into five groups: Group I (Control group); Group II (Orchiectomized group): bilateral orchiectomy was conducted on rats; Group III (BPH group): testosterone (TE) enanthate injection was used to induce BPH; Group IV (Protective group): rats were given SeNP before subjecting rats to BPH; Group V (Curative group): rats were succumbed to BPH, followed by administration of SeNP. Measurement of prostate specific antigen (PSA) and TE in serum was performed and prostates were weighed and prepared for histological, immunohistochemical and ultrastructural examination.
Results: In the BPH group, serum TE- and PSA-levels, as well as prostate weight, increased significantly and significant decreases in the protective and curative groups. Reduced acinar lumen, expansion of stroma and epithelial hyperplasia were noticed in the BPH group, which were ameliorated significantly both in protective and curative groups. There was an increase in PCNA immunoreaction in the BPH group and a decrease in both the protective and curative groups. On TEM of BPH group, the nuclei appeared irregular with dilated endoplasmic reticulum, loss of cell boundaries and apical microvilli. The protective group showed more improvement than the curative group.
Conclusions: The effects of SeNPs on BPH induced by TE in rats, were both protective and curative, although the protective effects were more pronounced
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Iterative prediction of chaotic time series using a recurrent neural network
Chaotic systems are known for their unpredictability due to their sensitive dependence on initial conditions. When only time series measurements from such systems are available, neural network based models are preferred due to their simplicity, availability, and robustness. However, the type of neutral network used should be capable of modeling the highly non-linear behavior and the multi-attractor nature of such systems. In this paper the authors use a special type of recurrent neural network called the ``Dynamic System Imitator (DSI)``, that has been proven to be capable of modeling very complex dynamic behaviors. The DSI is a fully recurrent neural network that is specially designed to model a wide variety of dynamic systems. The prediction method presented in this paper is based upon predicting one step ahead in the time series, and using that predicted value to iteratively predict the following steps. This method was applied to chaotic time series generated from the logistic, Henon, and the cubic equations, in addition to experimental pressure drop time series measured from a Fluidized Bed Reactor (FBR), which is known to exhibit chaotic behavior. The time behavior and state space attractor of the actual and network synthetic chaotic time series were analyzed and compared. The correlation dimension and the Kolmogorov entropy for both the original and network synthetic data were computed. They were found to resemble each other, confirming the success of the DSI based chaotic system modeling
ЕFFЕCT OF SOMЕ ЕSSЕNTIAL OILS ON GRЕY MOULD, CAUSЕD BY Botrytis cinеrеa ON TABLЕ GRAPЕ AT COLD-STORAGЕ
Еssеntial oils (ЕOs) from cinnamon (Cinnamon zylanicum), clovе (Syzygium aromaticum) camphor (Еucalyptus globulus), and rockеt (Еruca sativa), wеrе еvaluatеd for thеir botryocidal еffеct. In-vitro, Botrytis cinеrеa was еxposеd to 4 diffеrеnt concеntrations of ЕOs, using thrее diffеrеnt tеchniquеs, i.е. amеndеd mеdium, vapourisation, and volatilising. Cinnamon and clovе ЕOs wеrе thе highеst tеstеd concеntrations found to bе thе most еffеctivе in all tеchniquеs which complеtеly inhibitеd 100% of radial growth for B. cinеrеa in vitro. A post-harvеst trial to control grеy mould on grapе bunchеs of Flamе sееdlеss and Supеrior sееdlеss cvs. were conductеd using cinnamon and clovе oils in sеasons 2014 and 2015. Both of the two ЕOs wеrе usеd at concеntrations of 25, 50 and 100 µL./L-1air v/v, еxposеd as vapour trеatmеnt significantly supprеssеd grеy mould during thе cold-storagе. Thеrе was not a significancе diffеrеncеs obsеrvеd among both ЕOs trеatmеnts. Howеvеr, cinnamon at 100 µL.1L-1air v/v was thе most еffеctivе trеatmеnt to control grеy mould of both grapе cultivar
IMPACT OF FLAXSEED INCLUSION IN DAMASCUS GOAT'S RATION ON DIGESTIBILITY, SOME BLOOD PARAMETERS AND REPRODUCTIVE PERFORMANCE
Feeding flaxseed to dairy animals improve milk production and reproductive performance. So, the objective of our study was to investigate effect of inclusion flaxseed in Damascus goat's ration on its reproductive performance. Twenty-four Damascus goats (31.40 ±0.50 kg weight and 2-3 years old) were divided into three groups (randomly, eight animals each). The basic diet of control group (T1) consisted of 56.67% concentrate feed mixture (CFM) and 33.33% Alfalfa hay, while the groups T2 and T3 supplemented with 10% full fat soya, 5% flaxseed + 5% full fat soya and 10% flaxseed, respectively. Inclusion flaxseed in goat’s ration at rate of 5 and 10% resulted in significant increase in all nutrients digestibility, except nitrogen free extract digestibility (NFE) as well as the nutritive values as total digestible nutrients (TDN). Dry matter intakes (DMI) of the different experimental groups were comparable. Goats in T3 recorded the highest does conceived, twinning, conception and kidding rates % as well as total kids born, than other groups (T1 and T2). On the hand T3 recorded the lowest aborted does and barren does (Zero) compared to T1 and T2. Animals of T3 recorded significant higher of total protein, globulin, Albumin and urea concentration than T1 and T2. Concerning lipids profile, the animals of T3 recorded significant lower triglycerides, cholesterol and Low-density lipoprotein concentration than those of T1 and T2. While the animals of T3 recorded significant higher High-density lipoprotein concentration compared to T2 and T1. The body weight of does is not significantly affected by any of three treatments. In conclusion, flaxseed supplementations in Damascus goat's diets during the gestation period lead to improve total tract digestibility, reduced blood lipids and normalize renal and hepatic functions and improved its reproductive performance, especially those fed on diets containing 10% flaxseed
Sunset Yellow and Allura Red modulate Bcl2 and COX2 expression levels and confer oxidative stress-mediated renal and hepatic toxicity in male rats
Studies on the adverse health effects caused by azo dyes are insufficient and quite contradictory. This work aims to investigate the possible toxic effect of two types of widely used food additives, Sunset Yellow and Allura Red, by assessing the physiological, histopathological and ultrastructural changes in the liver and kidney. Also, we investigated the genotoxic effect of both dyes on white blood cells. Thirty adult male albino rats were divided into three groups of 10 animals each: control (received water), Sunset Yellow-treated (2.5 mg/kg body weight) and Allura Red-treated (seven mg/kg body weight). The doses were orally applied for 4 weeks. Our results indicated an increase in the biochemical markers of hepatic and renal function (Aspartate aminotransferase, alanine aminotransferase, urea, uric acid and creatinine) in animals administered with the azo dyes. We also observed a noticeable increase in MDA and a marked decrease in total antioxidant levels in azo dye-treated animals compared to controls. Conversely, both dyes adversely affected the liver and kidney of albino rats and altered their histological and fine structure, with downregulation of Bcl2 and upregulation of COX2 expression. Our comet assay results showed a significant elevation in the fold change of tail moment in response to application of Sunset Yellow but not Allura Red. Collectively, we show that Sunset Yellow and Allura Red cause histopathological and physiological aberrations in the liver and kidney of male Wistar albino rats. Moreover, Sunset Yellow but not Allura Red induces a potential genotoxic effect
Server‐side workflow execution using data grid technology for reproducible analyses of data‐intensive hydrologic systems
Many geoscience disciplines utilize complex computational models for advancing understanding and sustainable management of Earth systems. Executing such models and their associated data preprocessing and postprocessing routines can be challenging for a number of reasons including (1) accessing and preprocessing the large volume and variety of data required by the model, (2) postprocessing large data collections generated by the model, and (3) orchestrating data processing tools, each with unique software dependencies, into workflows that can be easily reproduced and reused. To address these challenges, the work reported in this paper leverages the Workflow Structured Object functionality of the Integrated Rule‐Oriented Data System and demonstrates how it can be used to access distributed data, encapsulate hydrologic data processing as workflows, and federate with other community‐driven cyberinfrastructure systems. The approach is demonstrated for a study investigating the impact of drought on populations in the Carolinas region of the United States. The analysis leverages computational modeling along with data from the Terra Populus project and data management and publication services provided by the Sustainable Environment‐Actionable Data project. The work is part of a larger effort under the DataNet Federation Consortium project that aims to demonstrate data and computational interoperability across cyberinfrastructure developed independently by scientific communities.Plain Language SummaryExecuting computational workflows in the geosciences can be challenging, especially when dealing with large, distributed, and heterogeneous data sets and computational tools. We present a methodology for addressing this challenge using the Integrated Rule‐Oriented Data System (iRODS) Workflow Structured Object (WSO). We demonstrate the approach through an end‐to‐end application of data access, processing, and publication of digital assets for a scientific study analyzing drought in the Carolinas region of the United States.Key PointsReproducibility of data‐intensive analyses remains a significant challengeData grids are useful for reproducibility of workflows requiring large, distributed data setsData and computations should be co‐located on servers to create executable Web‐resourcesPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137520/1/ess271_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137520/2/ess271.pd
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