WorldWideScience
1

The IKK complex contributes to the induction of autophagy  

UK PubMed Central (United Kingdom)

In response to stress, cells start transcriptional and transcription-independent programs that can lead to adaptation or death. Here, we show that multiple inducers of autophagy, including nutrient...Full Text Available

2010-02-03

2

The DFNA5 gene, responsible for hearing loss and involved in cancer, encodes a novel apoptosis-inducing protein  

British Library Electronic Table of Contents (United Kingdom)

DFNA5 was first identified as a gene causing autosomal dominant hearing loss (HL). Different mutations have been found, all exerting a highly specific gain-of-function effect, in which skipping of exon 8 causes the HL. Later reports revealed the involvement of the gene in different types of cancer. Epigenetic silencing of DFNA5 in a large percentage of gastric, colorectal and breast tumors and p53-dependent transcriptional activity have been reported, concluding that DFNA5 acts as a tumor suppressor gene in different frequent types of cancer. Despite these data, the molecular function of DFNA5 has not been investigated properly. Previous transfection studies with mutant DFNA5 in yeast and in mammalian cells showed a toxic effect of the mutant protein, which was not seen after transfection ...

2011-01-01

3

Resveratrol causes COX-2- and p53-dependent apoptosis in head and neck squamous cell cancer cells  

British Library Electronic Table of Contents (United Kingdom)

Cyclooxygenase-2 (COX-2) content is increased in many types of tumor cells. We have investigated the mechanism by which resveratrol, a stilbene that is pro-apoptotic in many tumor cell lines, causes apoptosis in human head and neck squamous cell carcinoma UMSCC-22B cells by a mechanism involving cellular COX-2. UMSCC-22B cells treated with resveratrol for 24 h, with or without selected inhibitors, were examined: (1) for the presence of nuclear activated ERK1/2, p53 and COX-2, (2) for evidence of apoptosis, and (3) by chromatin immunoprecipitation to demonstrate p53 binding to the p21 promoter. Stilbene-induced apoptosis was concentration-dependent, and associated with ERK1/2 activation, serine-15 p53 phosphorylation and nuclear accumulation of these proteins. These effects were blocked by ...

2008-01-01

4

Methods and Procedures for the Verification and Validation of Artificial Neural Networks  

CERN Document Server

Methods and Procedures for the Verification and Validation of Artificial Neural Networks

2006-01-01

5

Coherency Effects on Retinal Neural Processes (ERG) of ...  

Science.gov (United States)

... Accession Number : ADA111683. Title : Coherency Effects on Retinal Neural Processes (ERG) of Pseudemys. Descriptive ...

1981-12-01

6

Adaptive Nonlinear Autopilot for Anti-Air Missiles.  

Science.gov (United States)

... A control design methodology enabling the adaptive neural augmentation. ... As an example, the problem of designing a neural augmentation system. ...

2011-05-12

7

Functions of mammalian Cdc7 kinase in initiation/monitoring of DNA replication and development  

Energy Technology Data Exchange (ETDEWEB)

Cdc7 kinase plays an essential role in firing of replication origins by phosphorylating components of the replication complexes. Cdc7 kinase has also been implicated in S phase checkpoint signaling downstream of the ATR and Chk1 kinases. Inactivation of Cdc7 in yeast results in arrest of cell growth with 1C DNA content after completion of the ongoing DNA replication. In contrast, conditional inactivation of Cdc7 in undifferentiated mouse embryonic stem (ES) cells leads to growth arrest with rapid cessation of DNA synthesis, suggesting requirement of Cdc7 functions for continuation of ongoing DNA synthesis. Furthermore, loss of Cdc7 function induces recombinational repair (nuclear Rad51 foci) and G2/M checkpoint responses (inhibition of Cdc2 kinase). Eventually, p53 becomes highly activated and the cells undergo massive p53-dependent apoptosis. Thus, defective origin activation in mammalian cells can generate DNA replication ...

2003-11-27

8

Neural processing of asynchronous audiovisual speech perception  

UK PubMed Central (United Kingdom)

The temporal synchrony of auditory and visual signals is known to affect the perception of an external event, yet it is unclear what neural mechanisms underlie the influence of temporal synchrony...Full Text Available

2010-02-15

9

Neural Learning of Predicting Driving Environment  

Science.gov (United States)

... This paper presents our research in neural learning for predicting ... Denote this feature set as F4. ... can be observed that the SOC curves generated by ...

2008-06-01

15

Data compression using artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

This thesis investigates the application of artificial neural networks for the compression of image data. An algorithm is developed using the competitive learning paradigm which takes advantage of the parallel processing and classification capability of neural networks to produce an efficient implementation of vector quantization. Multi-Stage, tree searched, and classification vector quantization codebook design are adapted to the neural network design to reduce the computational cost and hardware requirements. The results show that the new algorithm provides a substantial reduction in computational costs and an improvement in performance.

1991-09-01

17

Probing Compulsive and Impulsive Behaviors, from Animal Models to Endophenotypes: A Narrative Review  

UK PubMed Central (United Kingdom)

Failures in cortical control of fronto-striatal neural circuits may underpin impulsive and compulsive acts. In this narrative review, we explore these behaviors from the perspective of neural processes...Full Text Available

2010-02-01

18

Object Repetition Leads to Local Increases in the Temporal Coordination of Neural Responses  

UK PubMed Central (United Kingdom)

Experience with visual objects leads to later improvements in identification speed and accuracy (“repetition priming”), but generally leads to reductions in neural activity in single-cell...Full Text Available

19

Multiple neural tube defects in the same patient with no neurological deficit  

UK PubMed Central (United Kingdom)

Congenital deformities involving the coverings of the nervous system are called neural tube defects (NTDs). NTD can be classified as neurulation defects, which occur by stage 12, and postneurulation...Full Text Available

2010-01-01

20

Interactions of Top-Down and Bottom-Up Mechanisms in Human Visual Cortex  

UK PubMed Central (United Kingdom)

Multiple stimuli present in the visual field at the same time compete for neural representation by mutually suppressing their evoked activity throughout visual cortex, providing a neural correlate...Full Text Available

2011-01-12

21

Fast, Scalable, Bayesian Spike Identification for Multi-Electrode Arrays  

UK PubMed Central (United Kingdom)

We present an algorithm to identify individual neural spikes observed on high-density multi-electrode arrays (MEAs). Our method can distinguish large numbers of distinct neural units, even when spikes...Full Text Available

22

EARLY BILATERAL SENSORY DEPRIVATION BLOCKS THE DEVELOPMENT OF COINCIDENT DISCHARGE IN RAT BARREL CORTEX  

UK PubMed Central (United Kingdom)

Several theories have proposed a functional role for synchronous neuronal firing in generating the neural code of a sensory perception. Synchronous neural activity develops during a critical...Full Text Available

2009-02-25

23

Behavioral Characteristics and Neural Mechanisms Mediating Performance in a Rodent Version of the Balloon Analog Risk Task  

UK PubMed Central (United Kingdom)

The tendency for some individuals to partake in high-risk behaviors (eg, substance abuse, gambling, risky sexual activities) is a matter of great public health concern, yet the characteristics and neural...Full Text Available

2010-07-01

24

Artificial neural network alarm method based on signal time-frequency characteristics  

International Nuclear Information System (INIS)

On the problem of alarm when parts are falling in nuclear power plant, the artificial neural network (ANN) alarm method based on the signal time-frequency characteristics was developed. The method was realized by the improved BP algorithm, and demonstrated with the data from simulation experiments

1998-06-01

25

A Nonlinear Dynamic Inversion L Adaptive Controller for - NASA  

Science.gov (United States)

Adaptive Neural Augmentation , AIAA Guidance, Navigation, and. Control Conference, Aug. 1998. [2] J. T. Kaneshige, J. Bull, and J. J. Totah, Generic Neural ...

27

NEUROPLASTICITY and INNOVATION  

Science.gov (United States)

OF VOCALIZED SPEECH THROUGH. ANALYSIS OF NEURAL SIGNALS. " SYNTHETIC TELEPATHY- WIRELESS. TRANSMISSION OF DECODED. THOUGHTS. " IMPLANTABLE MEMORY-ELIMINATES ...

29

Circuitry for a Wireless Microsystem for Neural Recording ...  

Science.gov (United States)

... in artificial intelligence, human physiology and biomedical prosthesis. ... central and peripheral nerve systems [1 ... CMOS circuit interface for multiplexed ...

2001-10-25

30

Computing Networks: A General Framework to Contrast Neural and Swarm Architectures  

CERN Document Server

Computing Networks (CNs) are defined. These are used to generalize neural and swarm architectures, namely artificial neural networks, ant colony optimization, and particle swarm optimization. The description of these architectures as CNs allows their comparison, distinguishing which properties enable them to perform complex computations and exhibit complex cognitive abilities. In this context, the most relevant characteristics of CNs are the existence multiple dynamical and functional scales.

2010-01-01

31

Application of artificial neural network to direct coal liquefaction research  

Energy Technology Data Exchange (ETDEWEB)

The catalytic liquefaction of a Chinese bituminous coal was simulated by artificial neural network. Three liquefaction variables, catalyst loading, reaction temperature and reaction time were used as inputs and tetrohydrofuran (THF) conversion and toluene (T) conversion were used as outputs. The artificial neural network, trained by the experimental data, could represent the liquefaction process, with a mean squared deviation of less than 0.025. 7 refs.,1 fig., 3 tabs.

1998-07-01

32

The effects of high-intensity pulsed electromagnetic field on proliferation and differentiation of neural stem cells of neonatal rats in vitro  

British Library Electronic Table of Contents (United Kingdom)

Summary The effects of high-intensity pulsed electromagnetic stimulation (HIPEMS) on proliferation and differentiation of neonatal rat neural stem cells in vitro were investigated. Neural stem cells derived from neonatal rats were exposed to 0.1 Hz, 0.5-10 Tesla (T) [8 groups of B-I, respectively], 5 stimuli of HIPEMF. The sham exposure controls were correspondingly established. Inverted phase contrast microscope was used to observe the cultured cells, MTT assay to detect the viability of the cells as expressed by absorbance (A) value, and flow cytometry to measure differentiation of neural stem cells. The results showed that A values of neural stem cells in both 3.0 T and 4.0 T groups were significantly higher than the other groups 24 to 168 h post HPEMS, indicating a strong promotion of ...

2009-01-01

33

Separation prediction in two dimensional boundary layer flows using artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)

2003-07-01

34

Separation prediction in two dimensional boundary layer flows using artificial neural networks  

International Nuclear Information System (INIS)

In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)

2003-05-28

35

Dynamic neuronal ensembles: Issues in representing structure change in object-oriented, biologically-based brain models  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the structure of dynamic neuronal ensembles (DNEs). DNEs represent a new paradigm for learning, based on biological neural networks that use variable structures. We present a computational neural element that demonstrates biological neuron functionality such as neurotransmitter feedback absolute refractory period and multiple output potentials. More specifically, we will develop a network of neural elements that have the ability to dynamically strengthen, weaken, add and remove interconnections. We demonstrate that the DNE is capable of performing dynamic modifications to neuron connections and exhibiting biological neuron functionality. In addition to its applications for learning, DNEs provide an excellent environment for testing and analysis of biological neural systems. An example of habituation and hyper-sensitization in biological systems, using a neural ...

1996-12-31

36

The effects of high-intensity pulsed electromagnetic field on proliferation and differentiation of neural stem cells of neonatal rats in vitro.  

Science.gov (United States)

The effects of high-intensity pulsed electromagnetic stimulation (HIPEMS) on proliferation and differentiation of neonatal rat neural stem cells in vitro were investigated. Neural stem cells derived from neonatal rats were exposed to 0.1 Hz, 0.5-10 Tesla (T) [8 groups of B-I, respectively], 5 stimuli of HIPEMF. The sham exposure controls were correspondingly established. Inverted phase contrast microscope was used to observe the cultured cells, MTT assay to detect the viability of the cells as expressed by absorbance (A) value, and flow cytometry to measure differentiation of neural stem cells. The results showed that A values of neural stem cells in both 3.0 T and 4.0 T groups were significantly higher than the other groups 24 to 168 h post HPEMS, indicating a strong promotion of the growth of neural stem cells (PHPEMS groups was the same as that in control group (P>0.05). It ...

2009-12-29

37

TGF-@b/BMPs: Crucial crossroad in neural autoimmune disorders  

British Library Electronic Table of Contents (United Kingdom)

Transforming growth factor beta (TGF-@b) has a crucial role in the differentiation of ectodermal cells to neural or epidermal precursors. TGF-@b and bone morphogenetic protein molecules (BMPs) are involved in many developmental processes, including cell proliferation and differentiation, apoptosis, mitotic arrest and intercellular interactions during morphogenesis. Additionally, the failure of central thymic tolerance mechanisms, leading to T cells with a skewed autoreactive response, is being described as a contributor in inflammatory processes in autoimmune diseases such as multiple sclerosis. Since TGF-@b and BMP proteins are crucial for the development of the neural system and the thymus, as well as for the differentiation of T cells, it is essential to further investigate their role i...

2011-01-01

38

Neural solution to the target intercept problems in a gun fire control system  

British Library Electronic Table of Contents (United Kingdom)

Time delay neural networks trained with the backpropagation algorithm are derived for the gun fire control system to correct the miss distance between a target and the projectiles from the gun. Its performance is compared to optimum linear filter based on minimum mean square error [R.E. Kalman, A new approach to linear filtering and prediction problems, J. Basic Eng. 82D (1960) 35-44.]. The structure of the proposed neural controller is described and performance results are shown.

2007-01-01

39

Neural network for prediction of superheater fireside corrosion  

Energy Technology Data Exchange (ETDEWEB)

Superheater corrosion causes vast annual losses to the power companies. If the corrosion could be reliably predicted, new power plants could be designed accordingly, and knowledge of fuel selection and determination of process conditions could be utilized to minimize superheater corrosion. If relations between inputs and the output are poorly known, conventional models depending on corrosion theories will fail. A prediction model based on a neural network is capable of learning from errors and improving its performance as the amount of data increases. The neural network developed during this study predicts superheater corrosion with 80 % accuracy at early stage of the project. (orig.) 10 refs.

1998-12-31

40

Computer aided monitoring of pump efficiency by using ART2 neural networks; ART2 nyurarunettowaku niyoru ponpuseino no rekka shindan shien  

Energy Technology Data Exchange (ETDEWEB)

As an application of ART2 neural networks, computer aided monitoring of pump efficiency is successfully examined for an industrial waste-liquid treatment process with measured data of valve openness and liquid flow rates. By running the neural networks in parallel, we confirm that accuracy to detect system changes is good, and the adjustment of classifier parameters is relatively easy. Investigating the resulting classes carefully, frequency of each class is correlated with pump efficiency. The relative amount of variables are also related to the classes. (author)

2000-05-10

41

A general regression artificial neural network for two-phase flow regime identification  

Energy Technology Data Exchange (ETDEWEB)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

2010-05-15

42

A general regression artificial neural network for two-phase flow regime identification  

International Nuclear Information System (INIS)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

2010-05-01

43

Use of neural network techniques to identify cosmic ray electrons and positrons during the 1993 balloon flight of the NMSU/Wizard-TS93 instrument  

Energy Technology Data Exchange (ETDEWEB)

The detectors used in the TS93 balloon flight produced a large volume of information for each cosmic ray trigger. Some of the data was visual in nature, other portions contained energy deposition and timing information. The data sets are amenable to conventional analysis techniques but there is no assurance that conventional techniques make full use of subtle correlations and relations amongst the detector responses. With the advent of neural network technologies, particularly adept at classification of complex phenomena, it would seem appropriate to explore the utility of neural network techniques to classify particles observed with the instruments. In this paper neural network based methodology for signal/background discrimination in a cosmic ray space experiment is discussed. Results are presented for electron and positron classification in the TS93 flight data set and will be compared to conventional analyses.

1995-09-01

44

Prospects of real-time ion temperature and rotation profiles based on neural-network charge exchange analysis  

Energy Technology Data Exchange (ETDEWEB)

A back-propagation neural network technique is used at JET to extract plasma parameters like ion temperature, rotation velocities or spectral line intensities from charge exchange (CX) spectra. It is shown that in the case of the C VI CX spectra, neural networks can give a good estimation (better than +-20% accuracy) for the main plasma parameters (Ti, V{sub rot}). Since the neural network approach involves no iterations or initial guesses the speed with which a spectrum is processed is so high (0.2 ms/spectrum) that real time analysis will be achieved in the near future. 4 refs., 8 figs.

1994-07-01

45

Organization of optic lobes that support motion detection in a semiterrestrial crab  

UK PubMed Central (United Kingdom)

There is a mismatch between the documentation of the visually guided behaviors and visual physiology of decapods (Malacostraca, Crustacea) and knowledge about the neural architecture of their...Full Text Available

2005-12-19

46

Neural integrated control for a free-floating space robot with suddenly changing parameters  

British Library Electronic Table of Contents (United Kingdom)

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system, this paper proposes a control strategy based on a variable structure neural integrated controller. This scheme does not need a precise space robot model, making use of the radial basis function neural network ability approach to learn about an uncertain model. The network weights are adjusted online in real-time. During the early period of the control phase and parameter changes, the variable structure controller compensates for the uncertain model which the neural network could not learn well. It also creates global asymptotic stability for the whole closed-loop system. Simulation results show that the controller can handle bad changea...

2011-01-01

47

Neural Tissues from the Implanted Stem Cells  

International Science & Technology Center (ISTC)

Morphological, Electrophysiological and Behavioral Investigations of the Nervous Tissue Developed from the Embryonic Matrix Zone Cells of the Dorsolateral Walls of Lateral Ventricles, Implanted into the Lesioned Regions of the Adult Rat's Brain

48

Implementation and Evaluation ... - Intelligent Systems Division - NASA  

Science.gov (United States)

[9] Rysdyk, R. T., and Calise, A. J., Fault Tolerant Flight control via Adaptive Neural Augmentation, AIAA. Guidance, Navigation, and Control Conference, Aug. ...

49

Evaluation of phenylpiperazines as targeting agents for neuroblastoma.  

UK PubMed Central (United Kingdom)

The potential of radiolabelled phenylpiperazines as agents for the detection and therapy of tumours of neural crest origin was evaluated by in vitro pharmacological studies with human neuroblastoma...Full Text Available

1996-09-01

50

Design of recurrent neural network power system stabilizer based on genetic algorithm  

Energy Technology Data Exchange (ETDEWEB)

A new recurrent neural network power system stabilizer (RNNPSS) based on genetic algorithm (GA) was presented. It shows faster convergence than the linear quadratic regulator (LQR) stabilizer in a multi-machine power system, because the proposed GA based neural network was first trained off-line to determine the optimal values of the learning rates. Otherwise, the RNNPSS consists of just two layers. As such, the time consumption of the damping oscillations is lower than with conventional methods. In addition, the operating range of the RNNPSS is greater than that of the LQR and conventional three layer neural networks, since the RNNPSS can greatly reduce system complexity and effectively damp system oscillations. 9 refs., 7 figs.

2008-07-01

51

Chronic Recording of Regenerating Vlllth Nerve Axons with a Sieve ...  

Science.gov (United States)

SLPL molecule to stimulate sufficient growth to have nerve sprouts enter the electrode and establish a neural interface for prosthesis control. ...

52

A new method for adiabatic flame temperature estimations of hydrocarbon fuels  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the application of artificial neural networks to adiabatic flame temperature prediction of hydrocarbon fuels. The investigation was conducted over a wide range of operating conditions in terms of fuel composition, pressure and temperature of reactants, fuel-air equivalence ratio and fuel vapour fraction. Several neural network models for predicting the flame temperature for different applicable fuel ranges were built and examined. The proper preparation of network training data and the appropriate choice of network parameters for achieving better prediction accuracy are discussed. The neural network prediction results were compared with those calculated by a thermodynamic and chemical equilibrium-based computer code - the NASA program CET89. It was shown that trained neural network models can provide the adiabatic flame temperature prediction with a good level of accuracy over a wide ...

1999-03-01

53

Title of paper: the induction of P-53 independent programmed cell death (apoptosis) with ionizing radiation and 5-fluorouracil (5-FU) in the HT-29 human colon carcinoma cell line  

International Nuclear Information System (INIS)

Purpose/Objective: The role of programmed cell death (apoptosis) as a cellular response to cancer therapy such as radiation or chemotherapy is the subject of much study, and manipulation of the apoptotic response in tumor cells may be valuable in the treatment of a variety of cancers. Both p53 dependent and independent apoptotic pathways have been identified; p53 is mutated in at least 50 % of human cancers and a majority of radiation resistant tumors contain p53 mutations. This study is designed to examine the induction of programmed cell death in a human colon carcinoma cell line that possesses two mutated p53 alleles. Ionizing radiation alone, or in combination with the chemotherapeutic drug 5-fluorouracil (5-FU), were used to elicit the apoptotic response. This study will focus on whether these treatments can induce a significant apoptotic response in cells that have mutated p53 alleles. Materials and Methods: HT-29 ...

1996-09-01

54

Studies of neural networks for engine control: application to the electromechanical valves engine; Etudes des reseaux de neurones pour le controle moteur: application a soupapes electromecaniques  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the control of an electromechanical valves engine. The control uses neural networks in order to build a non-linear model of engine filing which depends on the driven inlets. The aim is to build this real-time model and to integrate this model to a control system which performs an iterative inversion. (J.S.)

1997-12-31

55

Neural classifier construction using regularization, pruning and test error estimation.  

Science.gov (United States)

In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems. PMID:12662736

1998-12-01

56

Application of neural networks to pulse-shape analysis of Bragg curves  

Energy Technology Data Exchange (ETDEWEB)

A novel approach is presented to extract relevant parameters associated with the energy loss of ejectiles from nuclear reactions obtained by digitizing the signals of a Bragg curve spectrometer. New and more powerful computational paradigms allow a more thorough pulse-shape analysis. This is fulfilled using a back-propagation artificial neural network as a pattern identifier. The known problem of over-training is discussed.

2006-01-15

57

One-class classifier networks for target recognition applications  

Energy Technology Data Exchange (ETDEWEB)

Target recognition requires the ability to distinguish targets from non-targets, a capability called one-class generalization. Many neural network pattern classifiers fail as one-class classifiers because they use open decision boundaries. To function as one-class classifier, a neural network must have three types of generalization: within-class, between-class, and out-of-class. We discuss these three types of generalization and identify neural network architectures that meet these requirements. We have applied our one-class classifier ideas to the problem of automatic target recognition in synthetic aperture radar. We have compared three neural network algorithms: Carpenter and Grossberg`s algorithmic version of the Adaptive Resonance Theory (ART-2A), Kohonen`s Learning Vector Quantization (LVQ), and Reilly and Cooper`s Restricted Coulomb Energy network (RCE). The ART 2-A neural ...

1993-01-01

58

Neural-network-based voice-tracking algorithm  

Science.gov (United States)

A voice-tracking algorithm was developed and tested for the purposes of electronically separating the voice signals of simultaneous talkers. Many individuals suffer from hearing disorders that often inhibit their ability to focus on a single speaker in a multiple speaker environment (the cocktail party effect). Digital hearing aid technology makes it possible to implement complex algorithms for speech processing in both the time and frequency domains. In this work, an average magnitude difference function (AMDF) was performed on mixed voice signals in order to determine the fundamental frequencies present in the signals. A time prediction neural network was trained to recognize normal human voice inflection patterns, including rising, falling, rising-falling, and falling-rising patterns. The neural network was designed to track the fundamental frequency of a single talker based on the training procedure. The output of the ...

2002-11-01

59

Power system stabilizer based on inverse dynamics using an artificial neural network  

Energy Technology Data Exchange (ETDEWEB)

A stable power system stabilizer (PSS) based on the inverse dynamics of the controlled system using an artificial neural network (ANN) is suggested to enhance the dynamic performances of a power system. First, an output feedback control law is driven with some conditions satisfied, which guarantees the internal stability and robustness against the asymptotically stable external disturbances. Then the control law is implemented using the inverse dynamics of the controlled plant. The inverse dynamics of the controlled plant is identified by an ANN, inverse dynamics neural network (IDNN), off-line. The pole-shifting technique and a scaling factor are introduced for the control system to meet the conditions for internal stability and robustness. The proposed controller is applied to a typical single-machine infinite-bus power system. Simulation results under various operation conditions are given which show that the proposed controller damps the ...

1996-06-01

60

Pentobarbital anesthesia alters neural responses in the precedence effect  

British Library Electronic Table of Contents (United Kingdom)

The precedence effect (PE) is thought to be beneficial for proper localization and perception of sounds. The majority of recent physiological studies focus on the neural discharges correlated with PE in the inferior colliculus (IC). Pentobarbital anesthesia is widely used in physiological studies. However, little is known of the effect of pentobarbital on the discharge of neurons in PE. Neuronal responses in the IC from 23 male SD rats were recorded by standard extracellular recording techniques following presentation of 4ms white noise bursts, presented from either or both of two loud speakers, at different interstimulus delays (ISDs). The neural responses were recorded for off-line analysis before or after intraperitoneal administration of pentobarbital at a loading or maintenance dose. ...

2011-01-01

61

Grid cells generate an analog error-correcting code for singularly precise neural computation  

British Library Electronic Table of Contents (United Kingdom)

Entorhinal grid cells in mammals fire as a function of animal location, with spatially periodic response patterns. This nonlocal periodic representation of location, a local variable, is unlike other neural codes. There is no theoretical explanation for why such a code should exist. We examined how accurately the grid code with noisy neurons allows an ideal observer to estimate location and found this code to be a previously unknown type of population code with unprecedented robustness to noise. In particular, the representational accuracy attained by grid cells over the coding range was in a qualitatively different class from what is possible with observed sensory and motor population codes. We found that a simple neural network can effectively correct the grid code. To the best of our kn...

2011-01-01

62

Fault diagnosis on bottle filling plant using genetic-based neural network  

British Library Electronic Table of Contents (United Kingdom)

Timely detection of the pneumatic system problems is important in industry. Many techniques have been employed to solve this problem. In this paper, Genetic Algorithm (GA) based optimal configuration of neural networks is proposed for fault diagnostic of bottle filling systems. Back-propagation is used for neural networks algorithm. The back-propagation algorithm had six inputs and one output. A fitness function was designed to the minimize execution time of ANN model by keeping the number of hidden layer(s) and nodes as low as possible while the mean square error of estimated output error is minimized. The designed GA-ANN combination and the graphical user interface (GUI) eliminate the trial and error process for selection of the fastest and most accurate configuration. The performance of...

2011-01-01

63

Episodic Future Thinking Reduces Reward Delay Discounting through an Enhancement of Prefrontal-Mediotemporal Interactions  

British Library Electronic Table of Contents (United Kingdom)

Summary Humans discount the value of future rewards over time. Here we show using functional magnetic resonance imaging (fMRI) and neural coupling analyses that episodic future thinking reduces the rate of delay discounting through a modulation of neural decision-making and episodic future thinking networks. In addition to a standard control condition, real subject-specific episodic event cues were presented during a delay discounting task. Spontaneous episodic imagery during cue processing predicted how much subjects changed their preferences toward more future-minded choice behavior. Neural valuation signals in the anterior cingulate cortex and functional coupling of this region with hippocampus and amygdala predicted the degree to which future thinking modulated individual preference fu...

2010-01-01

64

Distributed delays stabilize neural feedback systems  

CERN Document Server

We consider the effect of distributed delays in neural feedback systems. The avian optic tectum is reciprocally connected with the nucleus isthmi. Extracellular stimulation combined with intracellular recordings reveal a range of signal delays from 4 to 9 ms between isthmotectal elements. This observation together with prior mathematical analysis concerning the influence of a delay distribution on system dynamics raises the question whether a broad delay distribution can impact the dynamics of neural feedback loops. For a system of reciprocally connected model neurons, we found that distributed delays enhance system stability in the following sense. With increased distribution of delays, the system converges faster to a fixed point and converges slower toward a limit cycle. Further, the introduction of distributed delays leads to an increased range of the average delay value for which the system's equilibrium point is stable. The enhancement of ...

2007-01-01

65

Cosmic ray antiproton/electron discrimination capability of the CAPRICE silicon-tungsten calorimeter using neural networks  

Energy Technology Data Exchange (ETDEWEB)

A data analysis based on an artificial neural network classifier is proposed to identify cosmic ray antiprotons detected with the CAPRICE silicon-tungsten imaging calorimeter against electron background in the energy range 1.2-4.0 GeV. A set of new physical variables, describing the events inside the calorimeter on the base of their different patterns, are introduced in order to discriminate between hadronic and electromagnetic showers. The ability of the artificial neural network classifier to perform a careful multidimensional analysis gives the possibility to identify antiprotons with an electron rejection 408{+-}85 (stat) at 95.0{+-}0.2 (stat)% of signal detection efficiency. The high accuracy achieved by this method improves substantially the efficiency in the evaluation of the cosmic ray antiproton spectrum. (orig.).

1996-11-01

66

Comparison of Support Vector Machine and Back Propagation Neural Network in Evaluating the Enterprise Financial Distress  

CERN Document Server

Recently, applying the novel data mining techniques for evaluating enterprise financial distress has received much research alternation. Support Vector Machine (SVM) and back propagation neural (BPN) network has been applied successfully in many areas with excellent generalization results, such as rule extraction, classification and evaluation. In this paper, a model based on SVM with Gaussian RBF kernel is proposed here for enterprise financial distress evaluation. BPN network is considered one of the simplest and are most general methods used for supervised training of multilayered neural network. The comparative results show that through the difference between the performance measures is marginal; SVM gives higher precision and lower error rates.

2010-01-01

67

A neural network based adaptive sliding mode controller: Application to a power system stabilizer  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a neural networks (NN) based adaptive sliding mode controller (SMC) is introduced. The selection of SMC feedback gains is normally based on one operating point and thus the performance of the controller away from the design operating point is, of necessity, a compromise. The adaptive SMC is proposed to overcome the limitations imposed on the effectiveness of the SMC under different operating conditions. Neural networks are used for online prediction of the optimal SMC gains when the operating point changes. The proposed method has been applied to a power system stabilizer (PSS) of a single machine power system. Simulation results are included to demonstrate the performance of the proposed control scheme.

2011-02-15

68

A neural network based adaptive sliding mode controller: Application to a power system stabilizer  

International Nuclear Information System (INIS)

In this paper, a neural networks (NN) based adaptive sliding mode controller (SMC) is introduced. The selection of SMC feedback gains is normally based on one operating point and thus the performance of the controller away from the design operating point is, of necessity, a compromise. The adaptive SMC is proposed to overcome the limitations imposed on the effectiveness of the SMC under different operating conditions. Neural networks are used for online prediction of the optimal SMC gains when the operating point changes. The proposed method has been applied to a power system stabilizer (PSS) of a single machine power system. Simulation results are included to demonstrate the performance of the proposed control scheme.

2011-02-01

69

nkx2.2a promotes specification and differentiation of a myelinating subset of oligodendrocyte lineage cells in zebrafish  

UK PubMed Central (United Kingdom)

During development, multipotent neural precursors give rise to oligodendrocyte progenitor cells (OPCs), which migrate and divide to produce additional OPCs. Near the end of embryogenesis and...Full Text Available

2008-05-01

70

[Improvement of the recognition probability about camouflage target based on BP neural network].  

Science.gov (United States)

Using static Michelson interferometer to get the spectrum information of measurement targets for spectrum identification, under the condition that the interference length is constant, the system can be optimized by BP neural network algorithm for the mixed spectral separation process. Thereby it can realize improving the recognition probability of camouflage target. Collecting the spectrum information in field of view (FOV) by the interferometer and linear array CCD detector, composing the set of mixed spectrum data, with known absorption spectrum of the material as a hidden layer of rules, it used BP neural network to separate the mixed spectrum data. Experiment with different distances, different combinations of mixed background spectrum as the initial data, using steel target (size: 1.5 m x 1.5 m) made of four kinds, the recognition probability of non-camouflage target is about 90% by BP neural network algorithm or the ...

2010-12-01

71

VAGUS NERVE STIMULATION REGULATES HEMOSTASIS IN SWINE  

UK PubMed Central (United Kingdom)

The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical stimulation of the...Full Text Available

2010-06-01

72

The Influence of Moderate Hypercapnia on Neural Activity in the Anesthetized Nonhuman Primate  

UK PubMed Central (United Kingdom)

Hypercapnia is often used as vasodilatory challenge in clinical applications and basic research. In functional magnetic resonance imaging (fMRI), elevated CO2 is applied to derive stimulus-induced...Full Text Available

2008-11-01

73

Task-Specific Codes for Face Recognition: How they Shape the Neural Representation of Features for Detection and Individuation  

UK PubMed Central (United Kingdom)

BackgroundThe variety of ways in which faces are categorized makes face recognition challenging for both synthetic and biological vision systems. Here we focus on two face processing...Full Text Available

74

Simultaneous expression of different transgenes in neurons and glia by combining in utero electroporation with the Tol2 transposon-mediated gene transfer system  

UK PubMed Central (United Kingdom)

In utero electroporation is widely used to study neuronal development and function by introducing plasmid DNA into neural progenitors during embryogenesis. This is an effective and...Full Text Available

2010-05-01

75

PyEEG: An Open Source Python Module for EEG/MEG Feature Extraction  

UK PubMed Central (United Kingdom)

Computer-aided diagnosis of neural diseases from EEG signals (or other physiological signals that can be treated as time series, e.g., MEG) is an emerging field that has gained much attention in past...Full Text Available

2011-01-01

76

Prediction of coal response to froth flotation based on coal analysis using regression and artificial neural network  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the combustible value (i.e. 100-Ash) and combustible recovery of coal flotation concentrate were predicted by regression and artificial neural network based on proximate and group macerals analysis. The regression method shows that the relationships between (a) in (ash), volatile matter and moisture (b) in (ash), in (liptinite), fusinite and vitrinite with combustible value can achieve the correlation coefficients (R{sup 2}) of 0.8 and 0.79, respectively. In addition, the input sets of (c) ash, volatile matter and moisture (d) ash, liptinite and fusinite can predict the combustible recovery with the correlation coefficients of 0.84 and 0.63, respectively. Feed-forward artificial neural network with 6-8-12-11-2-1 arrangement for moisture, ash and volatile matter input set was capable to estimate both combustible value and combustible recovery with correlation of 0.95. It was shown that the proposed neural ...

2009-10-15

77

Power of grammatical evolution neural networks to detect gene-gene interactions in the presence of error  

UK PubMed Central (United Kingdom)

BackgroundWith the advent of increasingly efficient means to obtain genetic information, a great insurgence of data has resulted, leading to the need for methods for analyzing this...Full Text Available

78

Percutaneous core excision and radiofrequency thermo-coagulation for the ablation of osteoid osteoma of the spine  

UK PubMed Central (United Kingdom)

Percutaneous radiofrequency ablation is the treatment of choice for osteoid osteoma of the appendicular skeleton. However, difficulties in localizing the lesion in the spine and its proximity to neural...Full Text Available

2009-03-01

79

P2X purinoceptors mediate an endothelium-dependent hyperpolarization in longitudinal smooth muscle of anterior mesenteric artery in young chickens  

UK PubMed Central (United Kingdom)

Background and purpose:The chicken anterior mesenteric artery contains an outer longitudinal smooth muscle layer, whose neural regulation remains to be elucidated. ATP evokes a depolarization...Full Text Available

2009-10-01

80

One-class classifiers and their application to synthetic aperture radar target recognition  

Energy Technology Data Exchange (ETDEWEB)

Target recognition requires the ability to distinguish targets from non-targets, a capability called one-class generalization. To function as a one-class classifier, a neural network must have three types of generalization: within-class, between-class, and out-of-class. We discuss these three types of generalization and identify neural network architectures that meet these requirements. We have applied our one-class classifier ideas to the problem of automatic target recognition in synthetic aperture radar. We have compared three neural network algorithms: Carpenter and Grossberg`s algorithmic version of the Adaptive Resonance Theory (ART-2A), Kohonen`s Learning Vector Quantization (LVQ), and Reilly and Cooper`s Restricted Columb Energy network (RCE). The ART 2-A neural network has given the best results, with 100% within-class, and out-of-class generalization. Experiments show that the network`s ...

1992-10-01

81

Neuronal regulation of cochlear blood flow in the guinea-pig.  

UK PubMed Central (United Kingdom)

1. Previous studies have shown that electrical stimulation (ES) of the guinea-pig cochlea causes a neurally mediated increase in cochlear blood flow (CBF). It is known that the centrifugal neuronal...Full Text Available

1994-11-01

82

Neural injury following stroke: are Toll-like receptors the link between the immune system and the CNS?  

UK PubMed Central (United Kingdom)

The CNS can exhibit features of inflammation in response to injury, infection or disease, whereby resident cells generate inflammatory mediators, including cytokines, prostaglandins, free radicals and...Full Text Available

2010-08-01

83

Multiple-Bond Kinetics from Single-Molecule Pulling Experiments: Evidence for Multiple NCAM Bonds  

UK PubMed Central (United Kingdom)

The kinetic parameters of single bonds between neural cell adhesion molecules were determined from atomic force microscope measurements of the forced dissociation of the homophilic protein-protein bonds....Full Text Available

2005-11-01

84

Mapping the Spatiotemporal Dynamics of Calcium Signaling in Cellular Neural Networks Using Optical Flow  

UK PubMed Central (United Kingdom)

An optical flow gradient algorithm was applied to spontaneously forming networks of neurons and glia in culture imaged by fluorescence optical microscopy in order to map functional calcium signaling...Full Text Available

2010-08-01

85

Manually controlled human balancing using visual, vestibular and proprioceptive senses involves a common, low frequency neural process  

UK PubMed Central (United Kingdom)

Ten subjects balanced their own body or a mechanically equivalent unstable inverted pendulum by hand, through a compliant spring linkage. Their balancing process was always characterized by repeated...Full Text Available

2006-11-15

86

MEG demonstrates a supra-additive response to facial and vocal emotion in the right superior temporal sulcus  

UK PubMed Central (United Kingdom)

An influential neural model of face perception suggests that the posterior superior temporal sulcus (STS) is sensitive to those aspects of faces that produce transient visual changes, including facial...Full Text Available

2009-11-24

87

Late onset muscle plasticity in the whisker pad of enucleated rats  

UK PubMed Central (United Kingdom)

Blindness leads to a major reorganization of neural pathways associated with touch. Because incoming somatosensory information influences motor output, it is plausible that motor plasticity occurs in...Full Text Available

2008-10-14

88

Intrinsic plasticity complements LTP in parallel fiber input gain control in cerebellar Purkinje cells  

UK PubMed Central (United Kingdom)

Synaptic gain control and information storage in neural networks are mediated by alterations in synaptic transmission, such as in long-term potentiation (LTP). Here, we show using both in...Full Text Available

2010-10-13

89

Intelligent techniques applied in identifying fraudsters industrial consumers of electricity; Tecnicas inteligentes aplicadas na identificacao de consumidores industriais fraudadores de energia eletrica  

Energy Technology Data Exchange (ETDEWEB)

The development of a computational intelligent tools based on neural network to identify commercial losses or fraud (theft energy), considering information from a database electric utility, is presented.

2009-07-01

90

Experimental autoimmune encephalomyelitis mobilizes neural progenitors from the subventricular zone to undergo oligodendrogenesis in adult mice  

UK PubMed Central (United Kingdom)

The destiny of the mitotically active cells of the subventricular zone (SVZ) in adult rodents is to migrate to the olfactory bulb, where they contribute to the replacement of granular and periglomerular...Full Text Available

2002-10-01

91

Evolution and Optimality of Similar Neural Mechanisms for Perception and Action during Search  

UK PubMed Central (United Kingdom)

A prevailing theory proposes that the brain's two visual pathways, the ventral and dorsal, lead to differing visual processing and world representations for conscious perception than those for action....Full Text Available

2010-09-01

92

Drosophila neuroblasts retain the daughter centrosome  

UK PubMed Central (United Kingdom)

During asymmetric mitosis, both in male Drosophila germline stem cells and in mouse embryo neural progenitors, the mother centrosome is retained by the self-renewed cell; hence suggesting...Full Text Available

93

Differential neural contributions to native- and foreign-language talker identification  

UK PubMed Central (United Kingdom)

Humans are remarkably adept at identifying individuals by the sound of their voice, a behavior supported by the nervous system’s ability to integrate information from voice and speech...Full Text Available

2009-12-01

94

DESIGN PRINCIPLES OF INSECT AND VERTEBRATE VISUAL SYSTEMS  

UK PubMed Central (United Kingdom)

A century ago, Cajal noted striking similarities between the neural circuits that underlie vision in vertebrates and flies. Over the past few decades, structural and functional studies have...Full Text Available

2010-04-15

95

Comparison of estimation capabilities of response surface methodology (RSM) with artificial neural network (ANN) in lipase-catalyzed synthesis of palm-based wax ester  

UK PubMed Central (United Kingdom)

BackgroundWax esters are important ingredients in cosmetics, pharmaceuticals, lubricants and other chemical industries due to their excellent wetting property. Since the naturally...Full Text Available

96

Clarke's Column Neurons as the Focus of a Corticospinal Corollary Circuit  

UK PubMed Central (United Kingdom)

Proprioceptive sensory signals inform the CNS of the consequences of motor acts, but effective motor planning involves internal neural systems capable of anticipating actual sensory feedback....Full Text Available

2010-10-01

97

CXCL12-Mediated Guidance of Migrating Embryonic Stem Cell-Derived Neural Progenitors Transplanted into the Hippocampus  

UK PubMed Central (United Kingdom)

Stem cell therapies for neurodegenerative disorders require accurate delivery of the transplanted cells to the sites of damage. Numerous studies have established that fluid injections to the hippocampus...Full Text Available

98

Bump time-frequency toolbox: a toolbox for time-frequency oscillatory bursts extraction in electrophysiological signals  

UK PubMed Central (United Kingdom)

Backgroundoscillatory activity, which can be separated in background and oscillatory burst pattern activities, is supposed to be representative of local synchronies of neural assemblies....Full Text Available

99

Behavioral consequences of dopamine deficiency in the Drosophila central nervous system  

UK PubMed Central (United Kingdom)

The neuromodulatory function of dopamine (DA) is an inherent feature of nervous systems of all animals. To learn more about the function of neural DA in Drosophila, we generated mutant...Full Text Available

2011-01-11

100

Antibody protects against lethal infection with the neurally spreading reovirus type 3 (Dearing).  

UK PubMed Central (United Kingdom)

The mammalian reoviruses have provided a valuable model for studying the pathogenesis of viral infections of the central nervous system (CNS). We have used this model to study the effect of antibody...Full Text Available

1988-12-01

101

Analysis of complex systems using neural networks  

Energy Technology Data Exchange (ETDEWEB)

The application of neural networks, alone or in conjunction with other advanced technologies (expert systems, fuzzy logic, and/or genetic algorithms), to some of the problems of complex engineering systems has the potential to enhance the safety, reliability, and operability of these systems. Typically, the measured variables from the systems are analog variables that must be sampled and normalized to expected peak values before they are introduced into neural networks. Often data must be processed to put it into a form more acceptable to the neural network (e.g., a fast Fourier transformation of the time-series data to produce a spectral plot of the data). Specific applications described include: (1) Diagnostics: State of the Plant (2) Hybrid System for Transient Identification, (3) Sensor Validation, (4) Plant-Wide Monitoring, (5) Monitoring of Performance and Efficiency, and (6) Analysis of Vibrations. Although specific ...

1992-01-01

102

Analysis of complex systems using neural networks  

Energy Technology Data Exchange (ETDEWEB)

The application of neural networks, alone or in conjunction with other advanced technologies (expert systems, fuzzy logic, and/or genetic algorithms), to some of the problems of complex engineering systems has the potential to enhance the safety, reliability, and operability of these systems. Typically, the measured variables from the systems are analog variables that must be sampled and normalized to expected peak values before they are introduced into neural networks. Often data must be processed to put it into a form more acceptable to the neural network (e.g., a fast Fourier transformation of the time-series data to produce a spectral plot of the data). Specific applications described include: (1) Diagnostics: State of the Plant (2) Hybrid System for Transient Identification, (3) Sensor Validation, (4) Plant-Wide Monitoring, (5) Monitoring of Performance and Efficiency, and (6) Analysis of Vibrations. Although specific ...

1992-12-31

103

An Evaluation of Cellular Neural Networks for the Automatic Identification of Cephalometric Landmarks on Digital Images  

UK PubMed Central (United Kingdom)

Several efforts have been made to completely automate cephalometric analysis by automatic landmark search. However, accuracy obtained was worse than manual identification in every study. The analogue-to-digital...Full Text Available

2009-01-01

104

Age-Related Deterioration of Rod Vision in Mice  

UK PubMed Central (United Kingdom)

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the...Full Text Available

2010-08-18

105

Adaptive power system stabilizer with previous programming of parameters and artificial neural network; Estabilizador de sistemas de potencia adaptativo com pre-programacao de parametros e rede neural artificial  

Energy Technology Data Exchange (ETDEWEB)

This work presents a digital adaptive Power System Stabilizer (PSS) which operates in a gain scheduling scheme. It`s parameters are designed for a lot of different operating regions in a P x Q plane (active and reactive powers), and saved in a microcomputer real time control. During working, the PSS identifies the present region of operation, and synthesizes its damping signal in accordance with the parameters for that region. As an extension of the method, a neural PSS, which uses the set of parameters of each region as a standard set to train a neural network to form this PSS, is also proposed. The tests presented show good performance for both PSS, when compared to a conventional (non adaptive) one. (author) 10 refs., 5 figs., 1 tab.; e-mail: jalb at guama.cpgee.ufpa.br

1997-12-31

106

The neural basis of visual behaviors in the larval zebrafish  

British Library Electronic Table of Contents (United Kingdom)

We review visually guided behaviors in larval zebrafish and summarise what is known about the neural processing that results in these behaviors, paying particular attention to the progress made in the last 2 years. Using the examples of the optokinetic reflex, the optomotor response, prey tracking and the visual startle response, we illustrate how the larval zebrafish presents us with a very promising model vertebrate system that allows neurocientists to integrate functional and behavioral studies and from which we can expect illuminating insights in the near future.

2009-01-01

107

Machine condition monitoring using neural networks and the likelihood function  

Energy Technology Data Exchange (ETDEWEB)

A model-based technique incorporating neural networks has been developed for process monitoring. The technique is intended for processes where the uncertainty in the reference model is larger than desired but where process measurements providing additional information about the behavior of the system are available. This data is used to reduce the uncertainty of the model. The technique has been implemented in a real-time system for monitoring operational changes of mechanical equipment for use in predictive maintenance applications. Tests on a peristaltic pump were conducted and demonstrate the advantages of the proposed technique.

1997-09-01

108

Incremental learning for recognizing handwritten characters using neural networks  

Energy Technology Data Exchange (ETDEWEB)

Artificial Neural Networks (ANNs) are parallel distributed processing machines. The unique characteristics of ANNs are: Fault tolerance, robustness, plasticity and generalization. These offer great potential in many AI applications such as character recognition. Handwritten character recognition is an intrinsically interesting problem, but the difficulties of this task are the many variations in the characters. A robust new incremental learning method, which combines supervised and unsupervised learning paradigms implemented by the Functional Link Net, is illustrated with experimental results. Clustering, based on unsupervised learning, classifies the input data into several categories. The supervised learning paradigm then further classifies the data in the clustered categories.

1989-01-01

109

Image analysis of complex microstructures by texture analysis and correlation with properties by neural networks; Bildanalyse komplexer Werkstoffgefuege durch Texturanalyse und Korrelation mit den Eigenschaften durch neuronale Netze  

Energy Technology Data Exchange (ETDEWEB)

By characterising the microstructure, quantitative image analysis allows to draw conclusions on the mechanical properties of materials. On fine microstructures with low contrast, e.g. of hardened steels, texture analysis has to be applied for quantification. Feeding texture parameters according to Haralick into a trained neural network, a correlation between the microstructure and the hardness of the steels C45 and 100Cr6 can be achieved. (orig.)

2001-08-01

110

Fuzzy-neural network based short term peak and average load forecasting (STPA LF) system with network security  

Energy Technology Data Exchange (ETDEWEB)

In this paper an attempt is made to forecast load using fuzzy neural network (FNN) for an integrated power system. Here, the proposed system uses a two stage FNN for a short term peak and average load forecasting (STPALF). The first stage FNN deals with the load forecasting and the second stage algorithm can be worked independently for network security. This technique is used to forecast load accurately on week days as well as holidays, weekends and some special occasions considering historical data of load and weather information and also take necessary control action for network security.

1997-12-31

111

Effect of the size of an artificial neural network used as pattern identifier  

Energy Technology Data Exchange (ETDEWEB)

A novel way to extract relevant parameters associated with the outgoing ions from nuclear reactions, obtained by digitizing the signals provided by a Bragg curve spectrometer (BCS) is presented. This allowed the implementation of a more thorough pulse-shape analysis. Due to the complexity of this task, it was required to take advantage of new and more powerful computational paradigms. This was fulfilled using a back-propagation artificial neural network (ANN) as a pattern identifier. Over training of ANNs is a common problem during the training stage. In the performance of the ANN there is a compromise between its size and the size of the training set. Here, this effect will be illustrated in relation to the problem of Bragg Curve (BC) identification. (Author)

2003-07-01

112

Comprehensive characterization of fuel, clad and wrapper materials and assemblies for fast reactors - towards design, development and performance  

International Nuclear Information System (INIS)

The paper provides a brief description of the fuel characterization for Fast Breeder Test Reactor (FBTR) and Prototype Fast Breeder Reactor (PFBR). The development and characterization of mechanical properties of Alloy D9 clad and wrapper tubes are discussed. The problems associated with fusion welding of Alloy D9 are outlined. Non-destructive characterization of cladding tubes by optimum encircling eddy current probes, on-line and off-line neural network methods is presented. Both the on-line and off-line neural network methods could readily detect and size defects specified by the designers

2004-01-01

113

Adaptive conventional power system stabilizer based on artificial neural network  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with an artificial neural network (ANN) based adaptive conventional power system stabilizer (PSS). The ANN comprises an input layer, a hidden layer and an output layer. The input vector to the ANN comprises real power (P) and reactive power (Q), while the output vector comprises optimum PSS parameters. A systematic approach for generating training set covering wide range of operating conditions, is presented. The ANN has been trained using back-propagation training algorithm. Investigations reveal that the dynamic performance of ANN based adaptive conventional PSS is quite insensitive to wide variations in loading conditions.

1995-12-31

114

Simultaneous prediction of coal rank parameters based on ultimate analysis using regression and artificial neural network  

Energy Technology Data Exchange (ETDEWEB)

Results from ultimate analysis, proximate and petrographic analyses of a wide range of Kentucky coal samples were used to predict coal rank parameters (vitrinite maximum reflectance (R{sub max}) and gross calorific value (GCV)) using multivariable regression and artificial neural network (ANN) methods. Volatile matter, carbon, total sulfur, hydrogen and oxygen were used to predict both R{sub max} and GCV by regression and ANN. Multivariable regression equations to predict R{sub max} and GCV showed R{sup 2} = 0.77 and 0.69, respectively. Results from the ANN method with a 2-5-4-2 arrangement that simultaneously predicts GCV and R{sub max} showed R{sup 2} values of 0.84 and 0.90, respectively, for an independent test data set. The artificial neural network method can be appropriately used to predict R{sub max} and GCV when regression results do not have high accuracy. (author)

2010-07-01

115

Selective metabolic stimulation of the subfornical organ and pituitary neural lobe by peripheral angiotensin II  

Energy Technology Data Exchange (ETDEWEB)

The subfornical organ is a major receptor area for one of the principal stimuli of thirst, the octapeptide, angiotensin II. In conscious water-sated rats, the authors examined the effects of intravenous infusion of angiotensin II on the rate of glucose utilization in the subfornical organ and in structures anatomically and functionally connected with it. Angiotensin II produced pressor and drinking responses and increased glucose utilization selectively in the subfornical organ and pituitary neural lobe and in no other brain structure. Treatment with the angiotensin II antagonist, sar1-leu8-angiotensin II, before intravenous administration of angiotensin II prevented metabolic stimulation of the subfornical organ and neural lobe. Captopril, an inhibitor of angiotensin-converting enzyme, reduced subfornical organ glucose metabolism to a level similar to that found in control animals. These results demonstrate that peripheral angiotensin II ...

1985-01-01

116

Reduction in radiation-induced brain injury by use of pentobarbital or lidocaine protection  

Energy Technology Data Exchange (ETDEWEB)

To determine if barbiturates would protect brain at high doses of radiation, survival rates in rats that received whole-brain x-irradiation during pentobarbital- or lidocaine-induced anesthesia were compared with those of control animals that received no medication and of animals anesthetized with ketamine. The animals were shielded so that respiratory and digestive tissues would not be damaged by the radiation. Survival rates in rats that received whole-brain irradiation as a single 7500-rad dose under pentobarbital- or lidocaine-induced anesthesia was increased from between from 0% and 20% to between 45% and 69% over the 40 days of observation compared with the other two groups (p less than 0.007). Ketamine anesthesia provided no protection. There were no notable differential effects upon non-neural tissues, suggesting that pentobarbital afforded protection through modulation of ambient neural activity during radiation exposure. ...

1990-05-01

117

Optimization of Evolutionary Neural Networks Using Hybrid Learning Algorithms  

CERN Document Server

Evolutionary artificial neural networks (EANNs) refer to a special class of artificial neural networks (ANNs) in which evolution is another fundamental form of adaptation in addition to learning. Evolutionary algorithms are used to adapt the connection weights, network architecture and learning algorithms according to the problem environment. Even though evolutionary algorithms are well known as efficient global search algorithms, very often they miss the best local solutions in the complex solution space. In this paper, we propose a hybrid meta-heuristic learning approach combining evolutionary learning and local search methods (using 1st and 2nd order error information) to improve the learning and faster convergence obtained using a direct evolutionary approach. The proposed technique is tested on three different chaotic time series and the test results are compared with some popular neuro-fuzzy systems and a recently developed cutting angle ...

2004-01-01

118

The use of artificial neural network analysis and multiple regression for trap quality evaluation: a case study of the Northern Kuqa Depression of Tarim Basin in western China  

Energy Technology Data Exchange (ETDEWEB)

Artificial neural network analysis is found to be far superior to multiple regression when applied to the evaluation of trap quality in the Northern Kuqa Depression, a gas-rich depression of Tarim Basin in western China. This is because this technique can correlate the complex and non-linear relationship between trap quality and related geological factors, whereas multiple regression can only describe a linear relationship. However, multiple regression can work as an auxiliary tool, as it is suited to high-speed calculations and can indicate the degree of dependence between the trap quality and its related geological factors which artificial neural network analysis cannot. For illustration, we have investigated 30 traps in the Northern Kuqa Depression. For each of the traps, the values of 14 selected geological factors were all known. While geologists were also able to assign individual trap quality values to 27 traps, they were less certain ...

2004-03-01

119

Studies with a generalized neuron based Pss on a multi-machine power system  

International Nuclear Information System (INIS)

An artificial neural network can be used as an intelligent controller to control non-linear, dynamic system through learning. It can easily accommodate non-linearities and time dependencies. Most common multi-layer feed-forward neural networks have drawbacks of large number of neurons and hidden layers required to deal with complex problems and require large training time. To overcome these drawbacks, a generalized neuron based non-linear controller has been developed and illustrated as a power system stabilizer. Studies on a five-machine power system show that the proposed controller can significantly improve the dynamic performance and provide good damping of the power system over a wide operating range.

2004-07-01

120

Recursive neural networks for processing graphs with labelled edges: theory and applications.  

Science.gov (United States)

In this paper, we introduce a new recursive neural network model able to process directed acyclic graphs with labelled edges. The model uses a state transition function which considers the edge labels and is independent both from the number and the order of the children of each node. The computational capabilities of the new recursive architecture are assessed. Moreover, in order to test the proposed architecture on a practical challenging application, the problem of object detection in images is also addressed. In fact, the localization of target objects is a preliminary step in any recognition system. The proposed technique is general and can be applied in different detection systems, since it does not exploit any a priori knowledge on the particular problem. Some experiments on face detection, carried out on scenes acquired by an indoor camera, are reported, showing very promising results. PMID:16181770

2005-09-21

121

Protein expression following heat shock in the nervous system of Locusta migratoria  

British Library Electronic Table of Contents (United Kingdom)

There is a thermal range for the operation of neural circuits beyond which nervous system function is compromised. Locusta migratoria is native to the semiarid regions of the world and provides an excellent model for studying neural phenomena. In this organism previous exposure to sublethal high temperatures (heat shock, HS) can protect neuronal function against future hyperthermia but, unlike many organisms, the profound physiological adaptations are not accompanied by a robust increase of Hsp70 transcript or protein in the nervous system. We compared Hsp70 increase following HS in the tissues of isolated and gregarious locusts to investigate the effect of population density. We also localized Hsp70 in the metathoracic ganglion (MTG) of gregarious locusts to determine if HS affects Hsp70 ...

2011-01-01

122

Prediction of thermal conductivity of ethylene glycol-water solutions by using artificial neural networks  

British Library Electronic Table of Contents (United Kingdom)

The objective of this study is to develop an artificial neural network (ANN) model to predict the thermal conductivity of ethylene glycol-water solutions based on experimentally measured variables. The thermal conductivity of solutions at different concentrations and various temperatures was measured using the cylindrical cell method that physical properties of the solution are being determined fills the annular space between two concentric cylinders. During the experiment, heat flows in the radial direction outwards through the test liquid filled in the annual gap to cooling water. In the steady state, conduction inside the cell was described by the Fourier equation in cylindrical coordinates, with boundary conditions corresponding to heat transfer between the solution and cooling water. ...

2009-01-01

123

Nuclear safety culture star-class assessment system based BP neural network  

International Nuclear Information System (INIS)

In order to build the safety culture for nuclear power industry, it is important to evaluate the safety culture scientifically. Considering the traits of safety culture in the nuclear power industry, 24 safety culture assessment indexes are established from 4 aspects such as Safety consciousness, Safety attitude, Safety action and Safety actuality by using the SMART criteria. Safety culture star-class assessment criterion is presented and safety culture star-class assessment system is developed by using Visual Basic 6.0 and BP neural network. The system has a better generalization ability, and it can show exactly which phase the safety culture is in. Experimental results show that safety culture star-class assessment is practical and easy to perform. (authors)

2007-02-01

124

Nonlinear black-box models and force-sensorless damping control for damping systems using magneto-rheological fluid dampers  

British Library Electronic Table of Contents (United Kingdom)

In vibration control field, magneto-rheological (MR) fluid dampers are semi-active control devices that have recently begun to receive more attention. This paper presents a nonlinear black-box model (BBM) and an inverse black-box model (IBBM) for the identification of a MR fluid damper and their application to design a novel force-sensorless control method for any damping system using that damper. The nonlinear model named 'black-box' is a simple direct modeling method which was designed based on fuzzy-neural technique. Characteristics of the damper in study are directly estimated through a fuzzy mapping system. In order to improve the model accuracy, neural network technique including back-propagation and gradient descent method were used to train the fuzzy parameters to minimize the mode...

2011-01-01

125

Non-invasive on-line two-phase flow regime identification employing artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

A novel non-invasive approach to the on-line identification of BWR two-phase flow regimes is investigated. The proposed approach receives neutron radiography images of coolant flow recordings as its input and performs feature extraction on each image via simple and directly computable statistical operators. The extracted features are subsequently used as inputs to an ensemble of self-organizing maps whose outputs demonstrate swift and accurate classification of each image into its corresponding flow regime. The novelty of the approach lies in the use of the self-organizing map which generates the different classes by itself, according to feature similarity of the corresponding images; this contrasts traditional artificial neural networks where the user has to define both the number of distinct classes as well as to supply separate training vectors for each class.

2009-05-01

126

Neural network and noise injection for the modeling of ozone pollution; Reseau de neurones et injection de bruit pour la modelisation de la pollution par l'ozone  

Energy Technology Data Exchange (ETDEWEB)

This study has been carried out in the framework of a collaboration between the laboratory of processes automation (LAP, Caen (France)), and Air Com, a monitoring network for the prevention of atmospheric pollution in Basse-Normandie. It aims at obtaining a medium and long term forecast of the ozone level above the Caen city. The expected goal is to foresee the pollution peaks exceeding the warning thresholds, but the rareness of such events make them more difficult to predict. In order to solve this kind of problem, a neural modeling method combined with a noise injection technique has been implemented in order to obtain a sufficiently performing model over the whole domain of operation. (J.S.)

2001-07-01

127

Influence of attention focus on neural activity in the human spinal cord during thermal sensory stimulation  

British Library Electronic Table of Contents (United Kingdom)

Perceptions of sensation and pain in healthy people are believed to be the net result of sensory input and descending modulation from brainstem and cortical regions depending on emotional and cognitive factors. Here, the influence of attention on neural activity in the spinal cord during thermal sensory stimulation of the hand was investigated with functional magnetic resonance imaging by systematically varying the participants' attention focus across and within repeated studies. Attention states included (1) attention to the stimulus by rating the sensation and (2) attention away from the stimulus by performing various mental tasks of watching a movie and identifying characters, detecting the direction of coherently moving dots within a randomly moving visual field and answering mentally-...

2011-01-01

128

Fault detection and diagnosis of a gearbox in marine propulsion systems using bispectrum analysis and artificial neural networks  

British Library Electronic Table of Contents (United Kingdom)

A marine propulsion system is a very complicated system composed of many mechanical components. As a result, the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft. It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis. For this reason, a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems. To monitor the gear conditions, the bispectrum analysis was first employed to detect gear faults. The amplitude-frequency plots containing gear characteristic sign...

2011-01-01

129

EEMD method and WNN for fault diagnosis of locomotive roller bearings  

British Library Electronic Table of Contents (United Kingdom)

The ensemble empirical mode decomposition (EEMD) can overcome the mode mixing problem of the empirical mode decomposition (EMD) and therefore provide more precise decomposition results. Wavelet neural network (WNN) possesses the advantages of both wavelet transform and artificial neural networks. This paper combines the merits of EEMD and WNN to propose an automated and effective fault diagnosis method of locomotive roller bearings. First, the vibration signals captured from the locomotive roller bearings are preprocessed by EEMD method and intrinsic mode functions (IMFs) are produced. Second, a kurtosis based method is presented and used to select the sensitive IMF. Third, time- and frequency-domain features are extracted from the sensitive IMF, its frequency spectrum and its envelope spe...

2011-01-01

130

Development of a pulse control-type MEMS microrobot with a hardware neural network  

British Library Electronic Table of Contents (United Kingdom)

This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 ? 4 ? 3.5 mm. The frame of the robot is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model was implemented as an HNN system to emulate the lo...

2011-01-01

131

Density measurements of coal samples by different probe gases and their interrelation  

Energy Technology Data Exchange (ETDEWEB)

Density is useful in deducing the spatial structure of coals. In this paper, nitrogen has been used instead of the commonly employed helium, for the gas displacement pycnometer based density determination of a number of coals of Indian origin. The results show that the nitrogen-based densities are always higher than the helium-based ones. Also, empirical relationships between the helium-based and nitrogen-based coal densities have been developed by two modeling methods, namely, multi-variable regression and artificial neural networks. Although the two models have fared well, the neural network model exhibits a relatively better prediction accuracy and generalization performance than the regression model. This study thus demonstrates that nitrogen, which is cheaper and easily available, can be used gainfully as the probe gas for estimating the true density of coals. 23 refs., 1 fig., 3 tabs.

2007-07-15

132

Artificial neural network modeling of physicochemical changes of shrimp during boiling  

British Library Electronic Table of Contents (United Kingdom)

Frozen boiled shrimp and dried shrimp are among the high-value fishery products of Thailand. During the production of these products boiling is one of the most important steps that affects significantly the product physicochemical properties, especially the quantity and quality of proteins, which in turn affect other apparent properties perceived by consumers. The protein changes are, however, difficult to evaluate comparing to other typical physical properties of shrimp. The objective of this study was therefore to develop an artificial neural network (ANN) model to predict the protein changes of shrimp in terms of protein loss and protein denaturation as a function of the boiling conditions, namely, concentration of salt solution and boiling time, as well as a rather easily determined ch...

2012-01-01

133

Application of feedback connection artificial neural network to seismic data filtering  

CERN Document Server

The Elman artificial neural network (ANN) (feedback connection) was used for seismic data filtering. The recurrent connection that characterizes this network offers the advantage of storing values from the previous time step to be used in the current time step. The proposed structure has the advantage of training simplicity by a back-propagation algorithm (steepest descent). Several trials were addressed on synthetic (with 10% and 50% of random and Gaussian noise) and real seismic data using respectively 10 to 30 neurons and a minimum of 60 neurons in the hidden layer. Both an iteration number up to 4000 and arrest criteria were used to obtain satisfactory performances. Application of such networks on real data shows that the filtered seismic section was efficient. Adequate cross-validation test is done to ensure the performance of network on new data sets.

2008-01-01

134

Analysis on Correlation between AE Parameters and Stress Intensity Factor using Principal Component Regression and Artificial Neural Network  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study is to develop the methodology which enables to identify the mechanical properties of element such as stress intensity factor by using the AE parameters. Considering the multivariate and nonlinear properties of AE parameters such as ringdown count, rise time, energy, event duration and peak amplitude from fatigue cracks of machine element the principal component regression(PCR) and artificial neural network(ANN) models for the estimation of stress intensity factor were developed and validated. The AE parameters were found to be very significant to estimate the stress intensity factor. Since the statistical values including correlation coefficients, standard mr of calibration, standard error of prediction and bias were stable, the PCR and ANN models for stress intensity factor were very robust. The performance of ANN model for unknown data of stress intensity factor was better than that of PCR model

2001-02-15

135

An application of artificial neural networks in breast cancer recognition using scintimammography  

International Nuclear Information System (INIS)

The aim of the study was to assess the usefulness of artificial neural networks (ANN) application in evaluation of scintimammography in the context of clinical data in the diagnosis of breast cancer. The results produced by ANN were compared with the diagnosis of two independent observers, nuclear medicine specialists. Material and methods: The clinical data and the numerical values derived from scintimammograms of 103 patients were the material for the study. The reference method was the result of histopathology study (core biopsy and /or FNB). Results: The overall sensitivity of physician diagnosis was 78% with specificity of 72%. The ANN produced 71% sensitivity and specificity of 73%. The physicians and ANN results were not significantly different (p=0.4619). Conclusions: Artificial neutral networks are useful tool in clinical diagnosis of breast cancer. (authors)

136

Amphiphilic Polyanhydride Films Promote Neural Stem Cell Adhesion and Differentiation  

British Library Electronic Table of Contents (United Kingdom)

Several challenges currently exist for rational design of functional tissue engineering constructs within the host, which include appropriate cellular integration, avoidance of bacterial infections, and low inflammatory stimulation. This work describes a novel class of biodegradable, amphiphilic polyanhydrides with many desirable protein-material and cell-material attributes capable of confronting these challenges. The biocompatible amphiphilic polymer films were shown to release laminin in a stable and controlled manner, promote neural cell adhesion and differentiation, and evade inflammatory responses of the immune system. Using high-throughput approaches, it was shown that polymer chemistry plays an integral role in controlling cell?film interactions, which suggests that these polyanhyd...

2011-01-01

137

A self-tuning power system stabilizer based on artificial neural network  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a systematic approach for designing a self-tuning power system stabilizer (PSS) based on artificial neural network (ANN). An ANN is used for self-tuning the parameters of PSS in real-time. The nodes in the input layer of the ANN receive generator terminal active power (P), reactive power (Q), and voltage (V{sub t}), while the nodes in the output layer provide the optimum PSS parameters, e.g. stabilizing gain (K{sub STAB}), time constants (T{sub 1} and T{sub 2}). A new approach for the selection of number of neurons in the hidden layer has been proposed. Investigations reveal that the dynamic performance of the system with self-tuning PSS based on ANN (ST-ANNPSS) is quite robust over a wide range of loading conditions and equivalent reactance, X{sub e}. (Author)

2004-07-01

138

A novel wavelet transform aided neural network based transmission line fault analysis method  

Energy Technology Data Exchange (ETDEWEB)

In the present scenario of market driven business, power supply has become more like a commodity. Reliable and quality power need to be ensured to meet customer requirements. In such a situation, it is extremely important that transmission line faults be identified accurately, reliably and in quick time. Advanced signal processing tools such as discrete wavelet transform (DWT) can be used very effectively for parameterisation and characterization of the fault signals. On the other hand, properly configured neural network (NN) can be utilized for classification of the faults based on the DWT signal. The present contribution uses electromagnetic transient program (EMTP) for modeling of a real transmission system and MATLAB for DWT and NN. Various types of faults have been simulated at different locations along the transmission line and an attempt has been made to correctly identify and locate the fault. (author)

2009-06-15

139

A novel wavelet transform aided neural network based transmission line fault analysis method  

British Library Electronic Table of Contents (United Kingdom)

In the present scenario of market driven business, power supply has become more like a commodity. Reliable and quality power need to be ensured to meet customer requirements. In such a situation, it is extremely important that transmission line faults be identified accurately, reliably and in quick time. Advanced signal processing tools such as discrete wavelet transform (DWT) can be used very effectively for parameterisation and characterization of the fault signals. On the other hand, properly configured neural network (NN) can be utilized for classification of the faults based on the DWT signal. The present contribution uses electromagnetic transient program (EMTP) for modeling of a real transmission system and MATLAB for DWT and NN. Various types of faults have been simulated at differ...

2009-01-01

140

A neuro power system stabilizer based on adaptive control technique  

Energy Technology Data Exchange (ETDEWEB)

A power system stabilizer based on GMV (Generalized Minimum Variance), one of the adaptive control techniques, is developed to enhance the dynamic performances of a power system using an Artificial Neural Network (ANN). The stabilizer consists of two parts. One part is Inverse Dynamics Neural Networks (IDNN), which is trained to identify the inverse dynamics of controlled plant and used as a one-step ahead controller, or inverse controller. The other part is Adaptive Reference Model (ARM), which prevents excessive controller output. The ARM produces the modified reference value by minimizing a cost function recursively on the assumption that the IDNN perfectly identifies the controlled plant. The IDNN is used in the minimization procedure to calculate the sensitivities. The proposed controller is simulated in a typical one-machine-infinite-bus power system to show its effectiveness to damp sustained low frequency oscillation. (author)

1996-12-31

141

A modular neural network for direction-of-arrival estimation of two sources  

British Library Electronic Table of Contents (United Kingdom)

This work addresses the problem of estimating the direction-of-arrival (DOA) of two sources using an array of sensors. This problem is mostly useful in radar applications, where we have few targets at each range bin. Super-resolution algorithms, such as maximum likelihood (ML) estimation and multiple signal classification (MUSIC), have been applied to this problem, but the former involves high computation efforts, while the later has poor estimation performance for coherent sources. In this work, we propose a DOA estimation network, named RBF-AML, which combines the approximated ML (AML) estimator and a radial basis function (RBF) neural network (NN). In the proposed RBF-AML network, the entire two dimensional DOA space is divided into multiple sectors covered by RBF experts. The AML funct...

2011-01-01

142

A Lamarckian Hybrid of Differential Evolution and Conjugate Gradients for Neural Network Training  

British Library Electronic Table of Contents (United Kingdom)

The paper describes two schemes that follow the model of Lamarckian evolution and combine differential evolution (DE), which is a population-based stochastic global search method, with the local optimization algorithm of conjugate gradients (CG). In the first, each offspring is fine-tuned by CG before competing with their parents. In the other CG is used to improve both parents and offspring in a manner that is completely seamless for individuals that survive more than one generation. Experiments involved training weights of feed-forward neural networks to solve three synthetic and four real-life problems. In six out of seven cases the DE?CG hybrid, which preserves and uses information on each solution?s local optimization process, outperformed two recent variants of DE.

2010-01-01

143

Unit commitment using hybrid models: a comparative study for dynamic programming, expert system, fuzzy system and genetic algorithms  

Energy Technology Data Exchange (ETDEWEB)

Hybrid models for solving unit commitment problem have been proposed in this paper. To incorporate the changes due to the addition of new constraints automatically, an expert system (ES) has been proposed. The ES combines both schedules of units to be committed based on any classical or traditional algorithms and the knowledge of experienced power system operators. A solution database, i.e. information contained in the previous schedule is used to facilitate the current solution process. The proposed ES receives the input, i.e. the unit commitment solutions from a fuzzy-neural network. The unit commitment solutions from the artificial neural network cannot offer good performance if the load patterns are dissimilar to those of the trained data. Hence, the load demands, i.e. the input to the fuzzy-neural network is considered as fuzzy variables. To take into account the uncertainty in load demands, a fuzzy decision making ...

2001-11-01

144

The ZNF804A gene: characterization of a novel neural risk mechanism for the major psychoses.  

Science.gov (United States)

Schizophrenia and bipolar disorder share genetic risk, brain vulnerability, and clinical symptoms. The ZNF804A risk variant, rs1344706, confers susceptibility for both disorders. This study aimed to identify neural mechanisms common to both schizophrenia and bipolar disorder through this variant's potential effects on cortical thickness, white matter tract integrity, and cognitive function. Imaging, genetics, and cognitive measures were ascertained in 62 healthy adults aged between 18 and 59 years. High-resolution multimodal MRI/DTI imaging was used to measure cortical thickness and major frontotemporal and interhemispheric white matter tracts. The general linear model was used to examine the influence of the ZNF804A rs1344706 risk variant on cortical thickness, white matter tract integrity, and cognitive measures. Individuals homozygous for the risk variant ('A' allele) demonstrated reduced cortical gray matter thickness in the superior temporal gyrus, and in the ...

2011-04-27

145

Pentobarbital anesthesia alters neural responses in the precedence effect.  

Science.gov (United States)

The precedence effect (PE) is thought to be beneficial for proper localization and perception of sounds. The majority of recent physiological studies focus on the neural discharges correlated with PE in the inferior colliculus (IC). Pentobarbital anesthesia is widely used in physiological studies. However, little is known of the effect of pentobarbital on the discharge of neurons in PE. Neuronal responses in the IC from 23 male SD rats were recorded by standard extracellular recording techniques following presentation of 4 ms white noise bursts, presented from either or both of two loud speakers, at different interstimulus delays (ISDs). The neural responses were recorded for off-line analysis before or after intraperitoneal administration of pentobarbital at a loading or maintenance dose. Data were assessed by one-way repeated measures analysis of variance and pairwise comparisons. When the ipsilateral stimuli were leading, pentobarbital at a ...

2011-05-06

146

On stochastic approximation algorithms for classes of PAC learning problems  

Energy Technology Data Exchange (ETDEWEB)

The classical stochastic approximation methods are shown to yield algorithms to solve several formulations of the PAC learning problem defined on the domain [o,1]{sup d}. Under some assumptions on different ability of the probability measure functions, simple algorithms to solve some PAC learning problems are proposed based on networks of non-polynomial units (e.g. artificial neural networks). Conditions on the sizes of these samples required to ensure the error bounds are derived using martingale inequalities.

1994-03-01

147

Mobile and Marine Robotics  

Science.gov (United States)

University research group with research areas: * Land based and submersible autonomous robots, (UUVs: AUVs and ROVs); * Controllers, electronics, sensor design and fusion, motion control; * Guidance and navigation of underwater vehicles; * AI, neural networks, fuzzy logic, subsumption control, behaviour based control; * Optical fibre and ultrasonic sensors for proximal object detection; * Robot arm control, visual servoing; * Imaging sonar applications; * Simulator development: UUV simulator; imaging sonar simulator; Aircraft/flight simulator.

2007-07-01

148

Lesions that functionally disconnect the anterior and posterodorsal sub-regions of the medial amygdala eliminate opposite-sex odor preference in male Syrian hamsters (Mesocricetus auratus)  

UK PubMed Central (United Kingdom)

In many rodent species, such as Syrian hamsters, reproductive behavior requires neural integration of chemosensory information and steroid hormone cues. The medial amygdala processes both of...Full Text Available

2010-02-17

149

Improve control with software monitoring technologies  

Energy Technology Data Exchange (ETDEWEB)

Multiple linear regression, principal component analysis, partial least squares, polynomial regression and artificial neural networks are popular techniques for process modeling. An industrial case study illustrates some of these technologies, with an emphasis on artificial neural networks. Experience with this and other projects indicates that while neural network models, combined with partial least squares when necessary, are an excellent tool for modeling, linear techniques may also be appropriate in some cases. Regardless of the specific method used, software analyzers are an attractive lower-cost alterative to hardware options in some monitoring applications. From a fundamental point of view, the result of chemical analysis can be considered as the dependent variable(s) of a process system having a number of independent variables. The independent variables are the causes and the chemical analysis is the effect. If the ...

1996-09-01

150

Heuristic paradigm: power electricity appliances; Aplicacoes de um paradigma heuristico adaptativo a eletricidade de potencia  

Energy Technology Data Exchange (ETDEWEB)

This paper presents general considerations concerning the application of artificial neural networks algorithms, more specifically the back-propagation learning algorithm and feed-forward multi-layer networks, to several problems in power system. The main application in power systems is the load forecasting, and two solution methods are used to solve it. (author). 45 figs., 32 tabs., 144 refs.

1994-12-31

151

Glutamate and the aggression neural circuit in adolescent anabolic steroid-treated Syrian hamsters (Mesocricetus auratus).  

Science.gov (United States)

Adolescent exposure to anabolic androgenic steroids (AAS) alters the development and activity of the glutamate neural system in the latero-anterior hypothalamus (LAH) in hamsters (Mesocricetus auratus); that is, an important neural component of the adolescent AAS-induced aggressive response. In this article, we used retrograde tracing to investigate glutamate-specific alterations in the connections between the LAH and several other nuclei implicated in adolescent AAS-induced aggression. Briefly, hamsters were treated with AAS or sesame-oil control during adolescence and then microinjected with retrograde tracer into the medial amygdala (MeA), lateral septum (LS), or bed nucleus of the stria terminalis (BNST). Brains were then processed for vesicular glutamate transporter 2 (VGLUT2) and examined for AAS-induced changes in the number VGLUT2 cells containing retrograde tracer (VGLUT2/tracer) within the LAH. It is interesting to note that while ...

2011-08-22

152

First-break refraction event picking and seismic data trace editing using neural networks  

Energy Technology Data Exchange (ETDEWEB)

Interactive seismic processing systems for editing noisy seismic traces and picking the first-break refraction events have been developed using a neural network learning algorithm. The authors employ a back propagation neural network (BNN) paradigm modified to improve the convergence rate of the BNN. The BNN is interactively trained'' to edit seismic data or pick first breaks by a human processor who judiciously selects and presents to the network examples of trace edits or refraction picks. The network then iteratively adjusts a set of internal weights until it can accurately duplicate the examples provided by the user. After the training session is completed, the BNN system an then process new data sets in a manner that mimics the human processor. Synthetic modeling studies indicated that the BNN uses many of the same subjective criteria that humans employ in editing and picking seismic data sets. Automated trace editing and ...

1993-01-01

153

Fault detection and diagnosis of a gearbox in marine propulsion systems using bispectrum analysis and artificial neural networks  

Science.gov (United States)

A marine propulsion system is a very complicated system composed of many mechanical components. As a result, the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft. It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis. For this reason, a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems. To monitor the gear conditions, the bispectrum analysis was first employed to detect gear faults. The amplitude-frequency plots containing gear characteristic signals were then attained based on the bispectrum technique, which could be regarded as an index actualizing forepart gear faults diagnosis. Both the back propagation ...

2011-03-01

154

ERK-dependent and -independent pathways trigger human neural progenitor cell migration  

International Nuclear Information System (INIS)

Besides differentiation and apoptosis, cell migration is a basic process in brain development in which neural cells migrate several centimeters within the developing brain before reaching their proper positions and forming the right connections. For identifying signaling events that control neural migration and are therefore potential targets of chemicals to disturb normal brain development, we developed a human neurosphere-based migration assay based on normal human neural progenitor (NHNP) cells, in which the distance is measured that cells wander over time. Applying this assay, we investigated the role of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) in the regulation of NHNP cell migration. Exposure to model substances like ethanol or phorbol 12-myristate 13-acetate (PMA) revealed a correlation between ERK1/2 activation and cell migration. The participation of phospho-(P-) ERK1/2 was confirmed by exposure ...

2007-05-15

155

CORIS[sup (TM)]: A knowledge based system for pitting corrosion. CORIS trademark : Wissensbasiertes System zur Lochkorrosion  

Energy Technology Data Exchange (ETDEWEB)

A knowledge based system for pitting corrosion is presented. It can be used for material selection for specific pitting corrosion conditions or to check the suitability of a chosen material. The user can enter his own knowledge. The expert system is an integration of traditional expert system technology and neural networks. (orig.)

1993-10-01

156

A wirelessly powered and controlled device for optical neural control of freely-behaving animals.  

Science.gov (United States)

Optogenetics, the ability to use light to activate and silence specific neuron types within neural networks in vivo and in vitro, is revolutionizing neuroscientists' capacity to understand how defined neural circuit elements contribute to normal and pathological brain functions. Typically, awake behaving experiments are conducted by inserting an optical fiber into the brain, tethered to a remote laser, or by utilizing an implanted light-emitting diode (LED), tethered to a remote power source. A fully wireless system would enable chronic or longitudinal experiments where long duration tethering is impractical, and would also support high-throughput experimentation. However, the high power requirements of light sources (LEDs, lasers), especially in the context of the extended illumination periods often desired in experiments, precludes battery-powered approaches from being widely applicable. We have developed a headborne device weighing 2 g ...

2011-06-23

157

A modeling study by response surface methodology and artificial neural network on culture parameters optimization for thermostable lipase production from a newly isolated thermophilic Geobacillus sp. strain ARM  

UK PubMed Central (United Kingdom)

BackgroundThermostable bacterial lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other...Full Text Available

158

A divergent Tbx6-related gene and Tbx6 are both required for neural crest and intermediate mesoderm development in Xenopus  

UK PubMed Central (United Kingdom)

AbstractT-box family transcription factors play many roles in Metazoan development. Here we characterise Tbx6r, a unique Tbx6 paralogue isolated from the amphibian Xenopus....Full Text Available

2010-04-01

159

[Molecular cloning and expression of an isotoxin gene, alpha-bungarotoxin, from Bungarus multicinctus].  

Science.gov (United States)

Abstract: Snake venom contains a number of small proteins,enzymes and other components,which displays a broad spectrum of biological activities. With the ability of specifically binding on acetylcholine acceptor, alpha-bungarotoxins are not only useful molecular probes in investigating the mechanism of neural signal transmission, but also potential pharmic preparations for neural disease treatment. In current research,cDNAs of Bungarus multicinutus venom gland were synthesized using SMART cDNA amplification kit and then, alpha-bungarotoxin genes were cloned and sequenced. Total of 20 clones were sequenced representing 14 isotoxin mRNAs of alpha-bungarotoxins. Among those clones, a novel isotoxin gene was subcloned into two expression plasmids, alpha-BgTX/pQE30a and alpha-BgTX/pGEX-4T-1, and transformed into E. coli. After inducing with IPTG, fused protein of GST-alpha-BgTX was successfully expressed at level of 30% gross proteins of bacteria. ...

2005-07-01

160

Theoretical and experimental aspects of supervised learning in artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

The topic of supervised learning within the conceptual framework of artificial neural network (ANN) models is addressed. An ANN is a parallel distributed processing system that consists of many computationally simple processing elements interconnected through uni-directional weighted connections. Such networks, which are roughly patterned after biological nervous systems, have been proposed for use in areas in which the traditional von Neumann computer architecture has been relatively unsuccessful. Learning in these networks is accomplished through the use of algorithms that adjust the values of the connection weights. The work presented here addresses the issue of improving the rate at which ANNs can learn to achieve the mapping of an input pattern to a desired output pattern. The most successful learning algorithms for accomplishing this task are based on gradient descent error minimization techniques. However, the large amount of training time that such ...

1989-01-01

161

Prediction of thermal conductivity of ethylene glycol-water solutions by using artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

The objective of this study is to develop an artificial neural network (ANN) model to predict the thermal conductivity of ethylene glycol-water solutions based on experimentally measured variables. The thermal conductivity of solutions at different concentrations and various temperatures was measured using the cylindrical cell method that physical properties of the solution are being determined fills the annular space between two concentric cylinders. During the experiment, heat flows in the radial direction outwards through the test liquid filled in the annual gap to cooling water. In the steady state, conduction inside the cell was described by the Fourier equation in cylindrical coordinates, with boundary conditions corresponding to heat transfer between the solution and cooling water. The performance of ANN was evaluated by a regression analysis between the predicted and the experimental values. The ANN predictions yield R{sup 2} in the range of 0.9999 and MAPE ...

2009-10-15

162

New options for simulating swivel momentum in car door hinges with neural networks. Neue Moeglichkeiten zur Simulation von Schwenkmomenten an Automobiltuerscharnieren mit Neuronalen Netzen  

Energy Technology Data Exchange (ETDEWEB)

The generation of a defined swivel momentum in car door hinges depends on numerous constructional and technical manufacturing parameters. If these parameters and their influence are to be investigated, then in addition to detailed experiments with variations in the parameters, methods are also required which enable the measuring data produced to be assessed in such a way that, in general, the non-linear relationships between initial and target size can be described sufficiently accurately. This paper explains the parameter reduction necessary in the experimental investigation, gives the results of the data assessment with conventional statistical methods and describes in particular the use of artificial neural networks (ANN) to construct so-called 'neuro hinge models' on the basis of the data resulting from the experiments. Parameter variations can be simulated with the hinge models and in this way optimal constructional and technical ...

1999-04-01

163

Neural net formulations for organically modified, hydrophobic silica aerogel  

Energy Technology Data Exchange (ETDEWEB)

Organic modification of aerogel chemical formulations is known to transfer desirable hydrophobicity to lightweight solids. However, the effects of chemical modification on other material constants such as elasticity, compliance, and sound dampening present a difficult optimization problem. Here a statistical treatment of a 9-variable optimization is accomplished with multiple regression and an artificial neural network (ANN). The ANN shows 95 percent prediction success for the entire data set of elasticity, compared to a multidimensional linear regression which shows a maximum correlation coefficient, R=0.782. In this case, using the Number of Categories Criterion for the standard multiple regression, traditional statistical methods can distinguish fewer than 1.83 categories (high and low elasticity) and cannot group or cluster the data to give more refined partitions. A non-linear surface requires at least 3 categories (high, low, and medium elasticities) to ...

1997-07-01

164

Gastric stromal tumors. CT findings; Tumori stromali gastrici. Aspetti con Tomografia Computerizzata  

Energy Technology Data Exchange (ETDEWEB)

Gastric stromal tumors are an ill-defined group of lesions arising from muscle wall cells and characterized by extremely variable biological patterns. Thanks to modern immunohistochemical and ultrastructural techniques, four main classes of these lesions have been identified, namely: (1) tumors with differentiation toward smooth muscle cells; (2) tumors with differentiation toward neural elements; (3) tumors with differentiation toward neural elements; (3) tumors with dual differentiation toward either cell type. It was investigated the yield of CT in diagnosing and characterizing gastric stromal tumors. It was retrospectively reviewed the CT findings of 38 patients (15 men and 23 women; mean age 51 years) with pathologically proven gastric stromal tumors, namely 31 of myoid origin, 4 of neural origin, 2 with both muscle and neural differentiation, 1 lacking differentiation with either cell type. The ...

2000-02-01

165

Estimation of gross calorific value based on coal analysis using regression and artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

Relationships of ultimate and proximate analysis of 4540 US coal samples from 25 states with gross calorific value (GCV) have been investigated by regression and artificial neural networks (ANNs) methods. Three set of inputs: (a) volatile matter, ash and moisture (b) C, H, N, O, S and ash (c) C, H{sub exclusive} {sub of} {sub moisture}, N, O{sub exclusive} {sub of} {sub moisture}, S, moisture and ash were used for the prediction of GCV by regression and ANNs. The multivariable regression studies have shown that the model (c) is the most suitable estimator of GCV. Running of the best arranged ANNs structures for the models (a) to (c) and assessment of errors have shown that the ANNs are not better or much different from regression, as a common and understood technique, in the prediction of uncomplicated relationships between proximate and ultimate analysis and coal GCV. (author)

2009-07-01

166

Development of the heated length to diameter correction factor on critical heat flux using the artificial neural networks  

Energy Technology Data Exchange (ETDEWEB)

With using artificial neural networks (ANNs), an analytical study related to the heated length effect on critical heat flux (CHF) has been carried out to make an improvement of the CHF prediction accuracy based on local condition correlations or table. It has been carried out to suggest a feasible criterion of the threshold length-to-diameter (L/D) value in which heated length could affect CHF. And within the criterion, a L/D correction factor has been developed through conventional regression. In order to validate the developed L/D correction factor, CHF experiments for various heated lengths have been carried out under low and intermediate pressure conditions. The developed threshold L/D correlation provides a new feasible criterion of L/D threshold value. The developed correction factor gives a reasonable accuracy for the original database, showing the error of -2.18% for average and 27.75% for RMS, and promising results for new experimental data. 7 refs., 12 ...

1998-12-31

167

Autism and the development of face processing.  

Science.gov (United States)

Autism is a pervasive developmental condition, characterized by impairments in non-verbal communication, social relationships and stereotypical patterns of behavior. A large body of evidence suggests that several aspects of face processing are impaired in autism, including anomalies in gaze processing, memory for facial identity and recognition of facial expressions of emotion. In search of neural markers of anomalous face processing in autism, much interest has focused on a network of brain regions that are implicated in social cognition and face processing. In this review, we will focus on three such regions, namely the STS for its role in processing gaze and facial movements, the FFA in face detection and identification and the amygdala in processing facial expressions of emotion. Much evidence suggests that a better understanding of the normal development of these specialized regions is essential for discovering the neural bases of face ...

2006-10-01

168

Application of artificial neural network methods for the lightning performance evaluation of Hellenic high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

Feed-forward (FF) artificial neural networks (ANN) and radial basis function (RBF) ANN methods were addressed for evaluating the lightning performance of high voltage transmission lines. Several structures, learning algorithms and transfer functions were tested in order to produce a model with the best generalizing ability. Actual input and output data, collected from operating Hellenic high voltage transmission lines, as well as simulated output data were used in the training, validation and testing process. The aims of the paper are to describe in detail and compare the proposed FF and RBF ANN models, to state their advantages and disadvantages and to present results obtained by their application on operating Hellenic transmission lines of 150kV and 400kV. The ANN results are also compared with results obtained using conventional methods and real records of outage rate showing a quite satisfactory agreement. The proposed ANN methods can be used by electric power ...

2007-01-15

169

An artificial neural network for directional comparison relaying of transmission lines  

Energy Technology Data Exchange (ETDEWEB)

Distance protection, differential protection and directional comparison schemes are presently used for protecting transmission lines. Directional comparison relays are set to respond to faults in the protection zone without intentional time delay and are, therefore, used where high-speed fault clearing is needed. Artificial Neural Networks (ANNs) can handle most situations which cannot be defined sufficiently for finding a deterministic solution. The design and testing of an ANN for directional comparison protection of transmission lines are presented in this paper. Training patterns were generated using voltage and current samples for faults at various locations along a transmission line. The faults were simulated using an electromagnetic transient program and a sample three-phase power system. The performance of the proposed discriminator was checked using data simulated for testing and the fault data recorded from 240 kV and 500 kV lines. Some of the test ...

1997-12-31

170

Reciprocal regulation of the neural and innate immune systems  

British Library Electronic Table of Contents (United Kingdom)

Innate immune responses are regulated by microorganisms and cell death, as well as by a third class of stress signal from the nervous and endocrine systems. The innate immune system also feeds back, through the production of cytokines, to regulate the function of the central nervous system (CNS), and this has effects on behaviour. These signals provide an extrinsic regulatory circuit that links physiological, social and environmental conditions, as perceived by the CNS, with transcriptional 'decision-making' in leukocytes. CNS-mediated regulation of innate immune responses optimizes total organism fitness and provides new opportunities for therapeutic control of chronic infectious, inflammatory and neuropsychiatric diseases.

2011-01-01

171

Recent advances in pharmacotherapy for dyspnea in COPD  

British Library Electronic Table of Contents (United Kingdom)

Dyspnea is the most distressing symptom experienced by those suffering from advanced stages of chronic obstructive pulmonary disease (COPD). Activity-related dyspnea in COPD is multifactorial but is associated with increased central neural drive, impaired dynamic respiratory mechanics and abnormal respiratory muscle function. Each of these components can potentially be targeted for pharmacotherapy. Recent advances in the pharmacotherapy of COPD include the development of new long-acting bronchodilators which, when combined, provide sustained improvements in dyspnea. Additionally, novel applications of older therapies such as opiates, furosemide, helium-oxygen, and statins show early promise as dyspnea-relieving interventions in COPD. Effective pharmacological manipulation of the affective ...

2011-01-01

172

Rapid Tools for Joint Inversion and Imaging. Final report  

Energy Technology Data Exchange (ETDEWEB)

The activities and results of a Small Business Innovation Research Phase II project entitled ''Rapid Tools for Joint Inversion and Imaging'' are presented. Research and development on three-dimensional methods to recover distributions of material property values from sparse data are reported. Innovations using artificial neural networks and extended Kalman filtering are described. The report also covers investigations on upscaling and downscaling, segmentation for data processing, and applications to ground penetrating radar and geohydraulic tomography.

2000-08-02

173

Optimisation of reactive dye removal by sequential electrocoagulation-flocculation method: comparing ANN and RSM prediction.  

Science.gov (United States)

The removal of Reactive Black 5 dye in an aqueous solution by electrocoagulation (EC) as well as addition of flocculant was investigated. The effect of operational parameters, i.e. current density, treatment time, solution conductivity and polymer dosage, was investigated. Two models, namely the artificial neural network (ANN) and the response surface method (RSM), were used to model the effect of independent variables on percentage of dye removal. The findings of this work showed that current density, treatment time and dosage of polymer had the most significant effect on percentage of dye removal (p0.8). PMID:21411950

2011-01-01

174

Mechanisms Underlying Visceral Hypersensitivity in Irritable Bowel Syndrome  

British Library Electronic Table of Contents (United Kingdom)

Visceral hypersensitivity is currently considered a key pathophysiological mechanism involved in pain perception in large subgroups of patients with functional gastrointestinal disorders, including irritable bowel syndrome (IBS). In IBS, visceral hypersensitivity has been described in 20%?90% of patients. The contribution of the central nervous system and psychological factors to visceral hypersensitivity in patients with IBS may be significant, although still debated. Peripheral factors have gained increasing attention following the recognition that infectious enteritis may trigger the development of persistent IBS symptoms, and the identification of mucosal immune, neural, endocrine, microbiological, and intestinal permeability abnormalities. Growing evidence suggests that these factors ...

2011-01-01

175

IDEAS: International Journal of Electronic Finance, Inderscience Enterprises Ltd  

Wastenet

... (restricted)] 406-419 E-auction in China: the case of Taobao by June Lu & Lu-Zhuang Wang & Chun-Sheng Yu [Downloadable! (restricted)] 420-441 The risks of business process outsourcing: a two-fold assessment in the German banking industry by Heiko Gewald & Jochen Franke [Downloadable! (restricted)] 442-459 Prediction of corporate financial health by Artificial Neural Network by Sumit Chakraborty & Sushil K. Sharma [Downloadable! (restricted)] 460-472 The development and performance evaluation of a Continuous Auditing Assistance System by ...

176

Continuum background suppression using various selectors  

International Nuclear Information System (INIS)

Continuum events represent an eminent source of background in any e+e- experiment. As these have a higher branching ratio than BB-bar events (at BaBar this ratio is estimated to about 3.5) or ?+?- events, efficient continuum background suppression is essential in many analyses. Using Artificial Neural Networks and the Nearest Neighbor Method we developed several selectors which, based only on the global event shape variables, efficiently tag BB-bar events and ?+?- events against the continuum background. These selectors could then be combined with the channel specific information in various types of analyses. The study was done using a parametric Monte Carlo.

1999-10-04

177

The role of the mesenchyme in mouse neural fold elevation. II. Patterns of hyaluronate synthesis and distribution in embryos developing in vitro  

Energy Technology Data Exchange (ETDEWEB)

Hyaluronate (HA) distribution patterns were examined in the cranial mesenchyme underlying the mesencephalic neural folds of mouse embryos maintained in roller tube culture. Using standard image-processing techniques, the digitized images of Alcian blue-stained or 3H-glucosamine-labeled sections digested with an enzyme specific for HA, were subtracted from adjacent, undigested sections. The resultant difference picture images (DPI) accurately depicted the distribution of stained or labeled HA within the cranial mesenchyme. 3H-glucosamine-labeled HA was distributed uniformly throughout the cranial mesenchyme as 12, 18, and 24 hr of culture. By contrast, the mesenchyme was uniformly stained with Alcian blue at 12 hr, but stain intensity decreased in the central regions of the mesenchyme at 18 and 24 hr. HA distribution patterns were also examined in the cranial mesenchyme of embryos cultured in the presence of diazo-oxo-norleucine (DON), a glutamine analogue that ...

1990-06-01

178

Prediction of coal grindability based on petrography, proximate and ultimate analysis using multiple regression and artificial neural network models  

Energy Technology Data Exchange (ETDEWEB)

The effects of proximate and ultimate analysis, maceral content, and coal rank (R{sub max}) for a wide range of Kentucky coal samples from calorific value of 4320 to 14960 (BTU/lb) (10.05 to 34.80 MJ/kg) on Hardgrove Grindability Index (HGI) have been investigated by multivariable regression and artificial neural network methods (ANN). The stepwise least square mathematical method shows that the relationship between (a) Moisture, ash, volatile matter, and total sulfur; (b) ln (total sulfur), hydrogen, ash, ln ((oxygen + nitrogen)/carbon) and moisture; (c) ln (exinite), semifusinite, micrinite, macrinite, resinite, and R{sub max} input sets with HGI in linear condition can achieve the correlation coefficients (R{sup 2}) of 0.77, 0.75, and 0.81, respectively. The ANN, which adequately recognized the characteristics of the coal samples, can predict HGI with correlation coefficients of 0.89, 0.89 and 0.95 respectively in testing process. It was determined that ln ...

2008-01-15

179

Optimizing the specific surface area of fly ash-based sorbents for flue gas desulfurization.  

Science.gov (United States)

High performance sorbents for flue gas desulfurization can be synthesized by hydration of coal fly ash, calcium sulfate, and calcium oxide. In general, higher desulfurization activity correlates with higher sorbent surface area. Consequently, a major aim in sorbent synthesis is to maximize the sorbent surface area by optimizing the hydration conditions. This work presents an integrated modeling and optimization approach to sorbent synthesis based on statistical experimental design and two artificial intelligence techniques: neural network and genetic algorithm. In the first step of the approach, the main and interactive effects of three hydration variables on sorbent surface area were evaluated using a full factorial design. The hydration variables of interest to this study were hydration time, amount of coal fly ash, and amount of calcium sulfate and the levels investigated were 4-32 h, 5-15 g, and 0-12 g, respectively. In the second step, a ...

2005-07-05

180

Hypercapnic normalization of BOLD fMRI: comparison across field strengths and pulse sequences.  

DEFF Research Database (Denmark)

The blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) signal response to neural stimulation is influenced by many factors that are unrelated to the stimulus. These factors are physiological, such as the resting venous cerebral blood volume (CBV(v)) and vessel size, as well as experimental, such as pulse sequence and static magnetic field strength (B(0)). Thus, it is difficult to compare task-induced fMRI signals across subjects, field strengths, and pulse sequences. This problem can be overcome by normalizing the neural activity-induced BOLD fMRI response by a global hypercapnia-induced BOLD signal. To demonstrate the effectiveness of the BOLD normalization approach, gradient-echo BOLD fMRI at 1.5, 4, and 7 T and spin-echo BOLD fMRI at 4 T were performed in human subjects. For neural stimulation, subjects performed sequential finger movements at 2 Hz, while for global stimulation, ...

2004-01-01

181

Generation of human cortical neurons from a new immortal fetal neural stem cell line  

International Nuclear Information System (INIS)

Isolation and expansion of neural stem cells (NSCs) of human origin are crucial for successful development of cell therapy approaches in neurodegenerative diseases. Different epigenetic and genetic immortalization strategies have been established for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new, clonal NSC (hc-NSC) line, derived from human fetal cortical tissue, based on v-myc immortalization. Using immunocytochemistry, we show that these cells retain the characteristics of NSCs after more than 50 passages. Under proliferation conditions, when supplemented with epidermal and basic fibroblast growth factors, the hc-NSCs expressed neural stem/progenitor cell markers like nestin, vimentin and Sox2. When growth factors were withdrawn, proliferation and expression of v-myc and telomerase were dramatically reduced, and the hc-NSCs differentiated into glia and neurons (mostly glutamatergic and ...

2007-02-01

182

Zebrafish embryo extracts promote sphere-forming abilities of human melanoma cell line  

British Library Electronic Table of Contents (United Kingdom)

Sphere-forming abilities in culture condition are considered a hallmark of cancer stem-like cells, which represents tumor cell invasiveness and stem-like characteristics. We aimed to show that the sphere-forming subpopulation of human malignant melanoma cell line WM-266-4 acts differently to zebrafish embryo extracts compared with their bulk counterpart. Spheres were maintained in neural stem cell culture conditions. The embryos of zebrafish at specific developmental stages were collected and the extracts were purified under 100 kDa. Spheres were treated with embyo extracts and proliferation assay and immunocytochemistry were conducted. Spheroid cells expressed nestin and epidermal growth factor receptor (EGFR) but not melanoma antigen recognized by T-cells (MART)1, indicating their stem-l...

2009-01-01

183

Two-photon calcium imaging from head-fixed Drosophila during optomotor walking behavior  

British Library Electronic Table of Contents (United Kingdom)

Drosophila melanogaster is a model organism rich in genetic tools to manipulate and identify neural circuits involved in specific behaviors. Here we present a technique for two-photon calcium imaging in the central brain of head-fixed Drosophila walking on an air-supported ball. The ball's motion is tracked at high resolution and can be treated as a proxy for the fly's own movements. We used the genetically encoded calcium sensor, GCaMP3.0, to record from important elements of the motion-processing pathway, the horizontal-system lobula plate tangential cells (LPTCs) in the fly optic lobe. We presented motion stimuli to the tethered fly and found that calcium transients in horizontal-system neurons correlated with robust optomotor behavior during walking. Our technique allows both behavior ...

2010-01-01

184

The influence of normal human ageing on automatic movements  

British Library Electronic Table of Contents (United Kingdom)

There is evidence that aged normal subjects have more difficulty in achieving automaticity than young subjects. The underlying central neural mechanism for this phenomenon is unclear. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the effect of normal ageing on automaticity. Aged healthy subjects were asked to practice self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Although it took more time, most aged subjects eventually performed the tasks automatically at the same level as the young subjects. Functional MRI results showed that, for bot...

2005-01-01

185

The Neural control of mood: The possible role of the adrenergic system in the medulla  

British Library Electronic Table of Contents (United Kingdom)

Mood in humans is a complex phenomenon that integrates emotion (e.g. happiness and sadness), cognition, perception, ideation, and action in a coherent manner. In bipolar disorder extremes of mood (up or down) occur outside the normal range, in which all the above functions are coherently affected. Mood is controlled by a series of separate but interactive brain circuits that involve much of the brain, but particularly the limbic system. The question addressed in this paper is whether the coordination of all these separate systems into one coherent functional mood is mediated by non-linear dynamics acting between these systems as equal participants; or whether it is affected by a single master regulator controlling the others. The possible roles, as master regulators, of non-linear dynamica...

2011-01-01

186

Testosterone reduces amygdalaorbitofrontal cortex coupling  

British Library Electronic Table of Contents (United Kingdom)

Testosterone influences various aspects of affective behavior, which is mediated by different brain regions within the emotion circuitry. Previous neuroimaging studies have demonstrated that testosterone increases neural activity in the amygdala. To investigate whether this could be due to altered regulation of amygdala functioning which is thought to be mediated by the prefrontal cortex, we studied the effects of exogenous testosterone on the interaction between the amygdala and other brain regions. Healthy middle-aged women received a single nasal testosterone dose in a randomized, placebo-controlled, crossover manner, and performed an emotional face matching task while their brain activity was measured with functional MRI. The results show that testosterone rapidly reduced functional co...

2010-01-01

187

Taxa-specific heat shock proteins are over-expressed with crowding in the Australian plague locust  

British Library Electronic Table of Contents (United Kingdom)

Most heat shock proteins (Hsps) function as molecular chaperones that help organisms to cope with stress. Although the best empirical evidence is related to heat shock, there is evidence that Hsps and their encoding genes are involved in resistance to other ecologically relevant types of stresses such as those imposed by high population density. We quantified density-dependent gene expression of large (i.e. Hsp40, Hsc70 and Hsp90) and small (Hsp20.5, Hsp20.6 and Hsp20.7) heat shock genes in neural tissue of fifth-instar nymphs of the Australian plague locust, Chortoicetes terminifera, using reverse transcription-quantitative PCR. Locusts are of particular interest when studying the influence of stress induced by high population density since they show an extreme form of phenotypic plastici...

2011-01-01

188

State-of-the-art in permeability determination from well log data: Part 1-A comparative study, model development  

Energy Technology Data Exchange (ETDEWEB)

This study discusses and compares, from a practical point of view, three different approaches for permeability determination from logs. These are empirical, statistical, and the recently introduced virtual measurement methods. They respectively make use of empirically determined models, multiple variable regression, and artificial neural networks. All three methods are applied to well log data from a heterogeneous formation and the results are compared with core permeability, which is considered to be the standard. In this first part of the paper we present only the model development phase in which we are testing the capability of each method to match the presented data. Based on this, the best two methods are to be analyzed in terms of prediction performance in the second part of this paper.

1995-12-31

189

Serotonin Inhibits Protein Feeding in the Blow Fly, Phormia regina (Meigen)  

British Library Electronic Table of Contents (United Kingdom)

Serotonin is an important signaling molecule involved in the control of feeding in flies and other animals. In this study, a potential neurohemal release site for serotonin and the effects of exogenous serotonin on protein feeding were examined in the black blow fly, Phormia regina. A dense network of varicose neural processes exhibiting serotonin-like immunoreactivity was identified on the dorsal region of the thoracico-abdominal ganglion in P. regina. This dorsal region of the central nervous system is a likely site for the release of serotonin into the hemolymph. Circulating serotonin may have multiple systemic effects on fly physiology, including modulating or regulating feeding related processes and diuresis. Injections of exogenous serotonin reduced protein meal size in female flies ...

2009-01-01

190

Real time automatic discriminating of ultrasonic flaws  

International Nuclear Information System (INIS)

This paper is concerned with the real time automatic discriminating of flaws from two categories; i. cracks (planar defect) and ii. Non-cracks (volumetric defect such as cluster porosity and slag) using pulse-echo ultrasound. The raw ultrasonic flaws signal were collected from a computerized robotic plane scanning system over the whole of each reflector as the primary source of data. The signal is then filtered and the analysis in both time and frequency domain were executed to obtain the selected feature. The real time feature analysis techniques measured the number of peaks, maximum index, pulse duration, rise time and fall time. The obtained features could be used to distinguish between quantitatively classified flaws by using various tools in artificial intelligence such as neural networks. The proposed algorithm and complete system were implemented in a computer software developed using Microsoft Visual BASIC 6.0 (author)

2009-07-20

191

Proceedings of the Pacific Knowledge Acquisition Workshop 2004  

CERN Document Server

Artificial intelligence (AI) research has evolved over the last few decades and knowledge acquisition research is at the core of AI research. PKAW-04 is one of three international knowledge acquisition workshops held in the Pacific-Rim, Canada and Europe over the last two decades. PKAW-04 has a strong emphasis on incremental knowledge acquisition, machine learning, neural nets and active mining. The proceedings contain 19 papers that were selected by the program committee among 24 submitted papers. All papers were peer reviewed by at least two reviewers. The papers in these proceedings cover the methods and tools as well as the applications related to develop expert systems or knowledge based systems.

2005-01-01

192

Photoperiod and gonadal hormones influence odor preferences of the male meadow vole, Microtus pennsylvanicus.  

Science.gov (United States)

Male meadow voles housed in a long photoperiod (14 h light/day, LP) preferred female to male odors, whereas males maintained in a short photoperiod (10 h light/day, SP) did not display preferences for odors of either sex. These odor-preference patterns matched those of free-living males during spring and autumn, respectively. The preference of LP male voles for female over male odors was eliminated by gonadectomy and reinstated by treatment with testosterone. In SP males, although gonadectomy did not affect odor choices, a preference for female odors was induced by testosterone treatment. Treatment with estradiol did not alter odor preferences of LP or SP males. In conjunction with previous result, the present findings suggest that hormonal responsiveness of neural substrates that control odor preferences are sexually dimorphic and may reflect sex differences in reproductive strategies. PMID:1615048

1992-05-01

193

Particle Flow at CMS and the ILC  

CERN Document Server

This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to improve the energy measurement of hadrons at CMS. The networks ...

2010-01-01

194

Optimal Dynamical Range of Excitable Networks at Criticality  

CERN Document Server

A recurrent idea in the study of complex systems is that optimal information processing is to be found near bifurcation points or phase transitions. However, this heuristic hypothesis has few (if any) concrete realizations where a standard and biologically relevant quantity is optimized at criticality. Here we give a clear example of such a phenomenon: a network of excitable elements has its sensitivity and dynamic range maximized at the critical point of a non-equilibrium phase transition. Our results are compatible with the essential role of gap junctions in olfactory glomeruli and retinal ganglionar cell output. Synchronization and global oscillations also appear in the network dynamics. We propose that the main functional role of electrical coupling is to provide an enhancement of dynamic range, therefore allowing the coding of information spanning several orders of magnitude. The mechanism could provide a microscopic neural basis for psychophysical laws.

2006-01-01

195

Moral Judgments Recruit Domain-General Valuation Mechanisms to Integrate Representations of Probability and Magnitude  

British Library Electronic Table of Contents (United Kingdom)

Summary Many important moral decisions, particularly at the policy level, require the evaluation of choices involving outcomes of variable magnitude and probability. Many economic decisions involve the same problem. It is not known whether and to what extent these structurally isomorphic decisions rely on common neural mechanisms. Subjects undergoing fMRI evaluated the moral acceptability of sacrificing a single life to save a larger group of variable size and probability of dying without action. Paralleling research on economic decision making, the ventromedial prefrontal cortex and ventral striatum were specifically sensitive to the "expected moral value" of actions, i.e., the expected number of lives lost/saved. Likewise, the right anterior insula was specifically sensitive to outcome p...

2010-01-01

196

Modular Traffic Sign Recognition applied to on-vehicle real-time visual detection of American and European speed limit signs  

CERN Document Server

We present a new modular traffic signs recognition system, successfully applied to both American and European speed limit signs. Our sign detection step is based only on shape-detection (rectangles or circles). This enables it to work on grayscale images, contrary to most European competitors, which eases robustness to illumination conditions (notably night operation). Speed sign candidates are classified (or rejected) by segmenting potential digits inside them (which is rather original and has several advantages), and then applying a neural digit recognition. The global detection rate is ~90% for both (standard) U.S. and E.U. speed signs, with a misclassification rate 150 minutes of video. The system processes in real-time ~20 frames/s on a standard high-end laptop.

2009-01-01

197

Learning algorithms for feedforward networks based on finite samples  

Energy Technology Data Exchange (ETDEWEB)

Two classes of convergent algorithms for learning continuous functions (and also regression functions) that are represented by feedforward networks, are discussed. The first class of algorithms, applicable to networks with unknown weights located only in the output layer, is obtained by utilizing the potential function methods of Aizerman et al. The second class, applicable to general feedforward networks, is obtained by utilizing the classical Robbins-Monro style stochastic approximation methods. Conditions relating the sample sizes to the error bounds are derived for both classes of algorithms using martingale-type inequalities. For concreteness, the discussion is presented in terms of neural networks, but the results are applicable to general feedforward networks, in particular to wavelet networks. The algorithms can be directly adapted to concept learning problems.

1994-09-01

198

Integrated evolutionary neural network approach with distributed computing for congestion management  

British Library Electronic Table of Contents (United Kingdom)

Electric supply industry is facing deregulation all over the world. Under deregulated power supply scenario, power transmission congestion has become more intensified and recurrent, as compared to conventional regulated power system. Congestion may lead to violation of voltage or transmission capacity limits, thus threatens the power system security and reliability. Also the growing congestion may lead to unanticipated divergent electricity pricing. Owing to these facts congestion management has become a crucial issue in the deregulated power system scenario. Fast and precise prediction of nodal congestion prices in real time deregulated/spot power market may enable market participants and system operators to keep pace with the congestion by taking preventive measures like transaction resc...

2010-01-01

199

High voltage transmission lines studies with the use of artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

The paper presents an alternative approach for the studies of high voltage transmission lines based on artificial intelligence and more specifically artificial neural networks (ANNs). In contrast to the existing conventional-analytical techniques and simulations which are using in the calculations empirical and/or approximating equations, this approach is based only on actual field data and actual measurements. The proposed approach is applied on high voltage transmission lines in order to calculate the lightning outages, on grounding systems in order to assess the grounding resistance and on high voltage transmission lines' polluted insulators in order to estimate the critical flashover voltage. The obtained results are very close to the actual ones for all three case studies, something which clearly implies that the ANN approach is well working and has an acceptable accuracy, constituting an additional tool of electric engineers. (author)

2009-12-15

200

Hearing loss in Turner syndrome  

British Library Electronic Table of Contents (United Kingdom)

ObjectiveTo address the characteristics of hearing loss in patients with Turner syndrome (TS), we evaluated hearing levels of patients with TS and analyzed causative factors.Study designThirty-three patients with TS (8 to 40 years of age) were studied through the use of audiological measurements, and causative factors were explored.ResultsTwenty cases (35 of 66 ears tested) showed high-frequency (8 kHz) sensory neural hearing loss (HFQ-SNHL). Fifteen cases (26 ears) and 15 cases (24 ears) of the impaired 20 cases were unresponsive to distortion-product otoacoustic emissions and transient-evoked otoacoustic emissions, respectively. HFQ-SNHL showed little relation to the history of middle ear infection and puberty, although middle ear infections were seen in 11 of the 20 cases. The hearing t...

2006-01-01

201

Growing RBFNN-based soft computing approach for congestion management  

British Library Electronic Table of Contents (United Kingdom)

In the emerging restructured power system, the congestion management (CM) has become extremely important in order to ensure the security and reliability of the system. In addition to this, lack of CM can impose a hindrance in electricity trading. This paper presents a novel, growing radial basis function neural network (GRBFNN)-based approach for CM. For achieving CM, Nodal congestion price (NCP) forecasting is performed in real time competitive power market. NCP forecasting is an effective way of price-based preventive CM as it directly indicates the presence as well as the severity of the congestion in the system. In present paper, GRBFNN has been developed for NCP forecasting dividing the whole power system into various congestion zones. An unsupervised learning vector quantization (VQ)...

2009-01-01

202

Global exponential stability of periodic solution for shunting inhibitory CNNs with delays  

Energy Technology Data Exchange (ETDEWEB)

By using the continuation theorem of coincidence degree theory and constructing suitable Lyapunov functions, we study the existence and stability of periodic solution for shunting inhibitory cellular neural networks (SICNNs) with delays x-bar {sub ij}(t)=-a{sub ij}(t)x{sub ij}(t)--bar B{sup kl}-bar Nr(i,j)B{sub ij}{sup kl}(t)f{sub ij}(x{sub kl}(t))x{sub ij}(t)--bar C{sup kl}-bar Nr(i,j)C{sub ij}{sup kl}(t)g{sub ij}(x{sub kl}(t-{tau}{sub kl}))x{sub ij}(t)+L{sub ij}(t)

2005-03-28

203

Global exponential stability of periodic solution for shunting inhibitory CNNs with delays  

International Nuclear Information System (INIS)

By using the continuation theorem of coincidence degree theory and constructing suitable Lyapunov functions, we study the existence and stability of periodic solution for shunting inhibitory cellular neural networks (SICNNs) with delays x-bar _i_j(t)=-a_i_j(t)x_i_j(t)--bar B"k"l-bar Nr(i,j)B_i_j"k"l(t)f_i_j(x_k_l(t))x_i_j(t)--bar C"k"l-bar Nr(i,j)C_i_j"k"l(t)g_i_j(x_k_l(t-#tau#_k_l))x_i_j(t)+L_i_j(t).

2005-03-28

204

Functionally defined substates within the human embryonic stem cell compartment.  

Science.gov (United States)

Human embryonic stem (ES) cells can undergo spontaneously differentiation in standard culture conditions, demonstrating that the undifferentiated state is relatively unstable. The heterogeneous expression of SSEA3 observed within human ES colonies, provides a means to examine undifferentiated stem cell substates. Through functional testing of single cells we have shown that undifferentiated ES cells can be segregated into functionally discrete subpopulations on the basis of SSEA3 expression: SSEA3(High), SSEA(Low) and SSEA3(Negative). Human ES subpopulations were found to be interconvertible, but they possess distinct properties when challenged to differentiate along the neural lineage. These data suggest that ES cells with pluripotent/self-renewal capacities can exhibit different responses to induction of differentiation. PMID:21763622

2011-05-11

205

Food reward functions as affected by obesity and bariatric surgery  

British Library Electronic Table of Contents (United Kingdom)

Roux-en-Y gastric bypass surgery (RYGB) remains to be the most effective long-term treatment for obesity and its associated comorbidities, but the specific mechanisms involved remain elusive. Because RYGB patients appear to no longer be preoccupied with thoughts about food and are satisfied with much smaller meals and calorically dilute foods, brain reward mechanisms could be involved. Just as obesity can produce maladaptive alterations in reward functions, reversal of obesity by RYGB could normalize these changes or even further reset the food reward system through changes in gut hormone secretion, aversive conditioning and/or secondary effects of weight loss. Future studies with longitudinal assessments of reward behaviors and their underlying neural circuits before and after surgery wil...

2011-01-01

206

Extended cognition and the space of social interaction  

British Library Electronic Table of Contents (United Kingdom)

The extended mind thesis (EM) asserts that some cognitive processes are (partially) composed of actions consisting of the manipulation and exploitation of environmental structures. Might some processes at the root of social cognition have a similarly extended structure? In this paper, I argue that social cognition is fundamentally an interactive form of space management-the negotiation and management of "we-space"-and that some of the expressive actions involved in the negotiation and management of we-space (gesture, touch, facial and whole-body expressions) drive basic processes of interpersonal understanding and thus do genuine social-cognitive work. Social interaction is a kind of extended social cognition, driven and at least partially constituted by environmental (non-neural) scaffold...

2011-01-01

207

Evaluation of cortical current density imaging methods using intracranial electrocorticograms and functional MRI  

British Library Electronic Table of Contents (United Kingdom)

Objective:EEG source imaging provides important information regarding the underlying neural activity from noninvasive electrophysiological measurements. The aim of the present study was to evaluate source reconstruction techniques by means of the intracranial electrocorticograms (ECoGs) and functional MRI.Methods:Five source imaging algorithms, including the minimum norm least square (MNLS), LORETA with Lp-norm (p equal to 1, 1.5 and 2), sLORETA, the minimum Lp-norm (p equal to 1 and 1.5; when p=2, the MNLS method is mathematically equivalent to the minimum Lp-norm) and L1-norm (the linear programming) methods, were evaluated in a group of 10 human subjects, in a paradigm with somatosensory stimulation. Cortical current density (CCD) distributions were estimated from the scalp somatosensor...

2007-01-01

208

Estimation of elbow flexion force during isometric muscle contraction from mechanomyography and electromyography  

British Library Electronic Table of Contents (United Kingdom)

Mechanomyography (MMG) is the muscle surface oscillations that are generated by the dimensional change of the contracting muscle fibers. Because MMG reflects the number of recruited motor units and their firing rates, just as electromyography (EMG) is influenced by these two factors, it can be used to estimate the force exerted by skeletal muscles. The aim of this study was to demonstrate the feasibility of MMG for estimating the elbow flexion force at the wrist under an isometric contraction by using an artificial neural network in comparison with EMG. We performed experiments with five subjects, and the force at the wrist and the MMG from the contributing muscles were recorded. It was found that MMG could be utilized to accurately estimate the isometric elbow flexion force based on the v...

2010-01-01

209

Early Language Learning and Literacy: Neuroscience Implications for Education  

British Library Electronic Table of Contents (United Kingdom)

The last decade has produced an explosion in neuroscience research examining young children's early processing of language that has implications for education. Noninvasive, safe functional brain measurements have now been proven feasible for use with children starting at birth. In the arena of language, the neural signatures of learning can be documented at a remarkably early point in development, and these early measures predict performance in children's language and pre-reading abilities in the second, third, and fifth year of life, a finding with theoretical and educational import. There is evidence that children's early mastery of language requires learning in a social context, and this finding also has important implications for education. Evidence relating socioeconomic status (SES) ...

2011-01-01

210

Downscaling of GCM forecasts to streamflow over Scandinavia  

DEFF Research Database (Denmark)

A seasonal forecasting technique to produce probabilistic and deterministic streamflow forecasts for 23 basins in Norway and northern Sweden is developed in this work. Large scale circulation and moisture fields, forecasted by the ECHAM4.5 model 4 months in advance, are used to forecast spring flows. The technique includes model output statistics (MOS) based on a non-linear Neural Network (NN) approach. Results show that streamflow forecasts from Global Circulation Model (GCM) predictions, for the Scandinavia region are viable and highest skill values were found for basins located in south-western Norway. The physical interpretation of the forecasting skill is that stations close to the Norwegian coast are directly exposed to prevailing winds from the Atlantic ocean, which constitute the principal source of predictive information from the atmosphere on the seasonal timescale.

2008-01-01

211

Development of a Weekly Load Forecasting Expert System  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the weekly load forecasting expert system (named WLoFy) which was developed and implemented for korea electric power corporation(KEPCO). WLoFy was designed to provide user oriented features with a graphical user interface to improve the user interaction. The various forecasting models such as exponential smoothing, multiple regression, artificial neural networks, rule-based model, and relative coefficient model also have been included in WLofy to increase the forecasting accuracy. The simulation based on historical data shows that the weekly forecasting results from WLoFy is an improvement when compared to the results from the conventional methods. Especially the forecasting accuracy on special days has been improved remarkably. (author). 9 refs., 5 figs., 6 tabs.

1999-04-01

212

Detect and classify faults using neural nets  

Energy Technology Data Exchange (ETDEWEB)

The analysis of transmission line faults is essential to the proper performance of the power system. It is required if protective relays are to take the appropriate action and in monitoring the performance of relays, circuit breakers, and other protective and control elements. The detection and classification of transmission line faults is a fundamental component of such fault analysis. Another application of fault analysis is in software packages for automated analysis of digital fault recorder (DFR) files. Recently, such a package, called DFR Assistant, was developed for substation applications. This program can be installed locally in a substation, in which case it is connected directly to the DFR via a high speed parallel link, or it can be installed at a central station, in which case it can be configured to automatically analyze events coming from all DFRs.

1996-10-01

213

Clonidine, octopaminergic receptor agonist, reduces protein feeding in the blow fly, Phormia regina (Meigen)  

British Library Electronic Table of Contents (United Kingdom)

Results in this study are consistent with those of Murdock and his colleagues who clearly demonstrated that clonidine, an agonist of octopaminergic receptors in some insects, significantly increases sucrose feeding. Their studies, however, did not examine the effect of clonidine on protein feeding. Injection of a 20mg/ml/fly dose of clonidine significantly reduces protein feeding in both sexes of Phormia regina, instead of stimulating feeding as is observed with carbohydrate feeding. The manner in which the flies are fed prior to starvation and the method of testing influences the amounts of diet consumed. It is proposed that the biogenic amines influence the state of hunger (i.e., protein versus carbohydrates) while other chemicals and neural mechanisms (i.e., such as sulfakinins and stre...

2007-01-01

214

Brain glucose sensing and neural regulation of insulin and glucagon secretion  

British Library Electronic Table of Contents (United Kingdom)

Glucose homeostasis requires the tight regulation of glucose utilization by liver, muscle and white or brown fat, and glucose production and release in the blood by liver. The major goal of maintaining glycemia at -5 mM is to ensure a sufficient flux of glucose to the brain, which depends mostly on this nutrient as a source of metabolic energy. This homeostatic process is controlled by hormones, mainly glucagon and insulin, and by autonomic nervous activities that control the metabolic state of liver, muscle and fat tissue but also the secretory activity of the endocrine pancreas. Activation or inhibition of the sympathetic or parasympathetic branches of the autonomic nervous systems are controlled by glucose-excited or glucose-inhibited neurons located at different anatomical sites, mainl...

2011-01-01

215

Application of an inverse input/output mapped ANN as a power system stabilizer  

Energy Technology Data Exchange (ETDEWEB)

An artificial neural network (ANN), trained as an inverse of the controlled plant, to function as a power system stabilizer (PSS) is presented in this paper. In order to make the proposed ANN PSS work properly, it was trained over the full working range of the generating unit with a large variety of disturbances. Data used to train the ANN PSS consists of the control input and the synchronous machine response with an adaptive PSS (APSS) controlling the generator. During training, the ANN was required to memorize the reverse input/output mapping of the synchronous machine. After the training, the output of the synchronous machine was applied as the input of the ANN PSS and the output of the ANN PSS was used as the control signal. Simulation results show that the proposed ANN PSS can provide good damping of the power system over a wide operating range and significantly improve the system performance.

1994-09-01

216

Air conditioning in high rise buildings; Conditionnement d'air dans les immeubles de grande hauteur  

Energy Technology Data Exchange (ETDEWEB)

This two-tomes book brings together the 108 presentations given at the first conference of the international institute of refrigeration (IIF/IIR) about air conditioning in high rise office buildings. The main themes are: general design and control systems, including split systems, radiant panels, fluctuating and gravity ventilation etc..; energy consumption, optimization and heat recovery; cold storage for peak shaving, including ice slurry circulation; indoor air quality; fire and smokes protection, protection against chimney effects and lighting spots; use of fuzzy logic and of neural networks. It includes also a description of the high rise building situation and works in progress in China, Japan and in some other countries. (J.S.)

1997-07-01

217

Advanced readout integrated circuit signal processing  

Science.gov (United States)

Readout integrated circuits (ROICs) for focal plane arrays (FPAs) have become increasingly complex to meet the needs of modern infrared systems. BAE Systems has pioneered a number of advanced signal processing architectures for FPA ROICs. Demonstrated signal processing capabilities of BAE Systems FPAs include analog-to-digital conversion, offset subtraction, individual pixel automatic gain compensation, transient noise suppression, on-FPA defect deselection, reconfigurable pixels, spatial neural network processing and subframe noise averaging. BAE Systems FPA advanced signal processing is not just for demonstrations, but is used in many of their deliverable FPAs, improving real system performance.

2006-06-01

218

Activation of a multisensory, multifunctional nucleus in the zebrafish midbrain during diverse locomotor behaviors  

British Library Electronic Table of Contents (United Kingdom)

Action potentials from the brain control the activity of spinal neural networks to produce, by as yet unknown mechanisms, a variety of motor behaviors. Particularly lacking are details on how identified descending neurons integrate diverse sensory inputs to generate specific locomotor patterns. We have examined the operations of the principal neurons in an intriguing midbrain nucleus, the nucleus of the medial longitudinal fasciculus (nMLF), in the larval zebrafish. The nMLF is the most rostral grouping of neurons that projects from the brain well into the spinal cord of teleost fishes, yet there is little direct physiological data available regarding its function. We report here that a distinct set of large, individually-identifiable neurons in nMLF (the MeL and MeM neurons) are activated...

2010-01-01

219

The influence of different SPECT reconstruction algorithms on cardiac ischemia with the use artificial neural networks  

International Nuclear Information System (INIS)

The aim of the study was the attempt to evaluate the influence of two different methods of cardiac perfusion SPECT reconstruction (FBP and ITW) on clinical efficacy in diagnosing the coronary artery disease as well as the cardiac ischemia detection in three areas of heart vascularized by main coronary arteries: LAD, LCX and RCA with the use of artificial neural networks (ANN). The study was performed retrospectively with the use of the diagnostic image records as well as clinical dataset of 43 patients. Myocardial perfusion stress/rest SPECT study and X-ray coronarography data were evaluated for each patient. The results of coronary angiography were considered the reference method. The cardiac SPECT data were reconstructed using the two different methods: filtered backprojection (FBP) and iterative Wallis method (ITW). The local perfusion deficits denominated in stress and rest study in three main vessel cardiac segments were the main input values for the ANN. The ...

220

Performance prediction of 20 kWp grid-connected photovoltaic plant at Trieste (Italy) using artificial neural network  

International Nuclear Information System (INIS)

Growing of PV for electricity generation is one of the highest in the field of the renewable energies and this tendency is expected to continue in the next years. Due to the various seasonal, hourly and daily changes in climate, it is relatively difficult to find a suitable analytic model for predicting the performance of a grid-connected photovoltaic (GCPV) plant. In this paper, an artificial neural network is used for modelling and predicting the power produced by a 20 kWp GCPV plant installed on the roof top of the municipality of Trieste (latitude 45 deg. 40'N, longitude 13 deg. 46'E), Italy. An experimental database of climate (irradiance and air temperature) and electrical (power delivered to the grid) data from January 29th to May 25th 2009 has been used. Two ANN models have been developed and implemented on experimental climate and electrical data. The first one is a multivariate model based on the solar irradiance and the air temperature, while the second ...

2010-12-01

221

Neuroophthalmology A brief Vademecum  

International Nuclear Information System (INIS)

The stunning, intricate interaction between the visual, vestibular and optomotor systems--each a miracle on its own--ensures maintenance of orientation in space as well as visual recognition and target selection despite a host of sensory conflicts and adversary disturbances. Their main goals are to keep a target of interest on the fovea by either maintaining or shifting the direction of gaze in order to produce an accurate internal representation of the visual surroundings, in particular the selected target, and to continuously mirror the spatial relationship between these various visual elements and the self. Not surprising, the implementation of this host of elaborate neural networks encompasses almost every part of the brain, including the brainstem, cerebellum, extrapyramidal system and many areas of the cerebral cortex. Thus far, these systems are among the best investigated in brain research; and enormous knowledge was amassed over the last century employing ...

2004-01-01

222

Cadmium inhibits neurogenesis in zebrafish embryonic brain development  

International Nuclear Information System (INIS)

Cadmium is a non-essential heavy metal found abundantly in the environment. Children of women exposed to cadmium during pregnancy display lower motor and perceptual abilities. High cadmium body burden in children is also related to impaired intelligence and lowered school achievement. However, little is known about the molecular and cellular basis of developmental neurotoxicity in the sensitive early life stages of animals. In this study, we explore neurological deficits caused by cadmium during early embryonic stages in zebrafish by examining regionalization of the neural tube, pattern formation and cell fate determination, commitment of proneural genes and induction of neurogenesis. We show that cadmium-treated embryos developed a smaller head with unclear boundaries between the brain subdivisions, particularly in the mid-hindbrain region. Embryos display normal anterior to posterior regionalization; however, the commitment of neural ...

2008-05-01

223

A study of the importance of occupancy to building cooling load in prediction by intelligent approach  

International Nuclear Information System (INIS)

Research highlights: #-># The building occupancy affecting the cooling load prediction is studied. #-># PENN model is adopted in this study for predicting the building cooling load. #-># Statistical approach is adopted to result a less prejudice prediction performance. #-># Results show that occupancy data can significantly improve the prediction. -- Abstract: Building cooling load prediction is one of the key factors in the success of energy-saving measures. Many computational models available in the industry today have been developed from either forward or inverse modeling approaches. However, most of these models require extensive computer resources and involve lengthy computation. This paper discusses the use of data-driven intelligent approaches, a probabilistic entropy-based neural (PENN) model to predict the cooling load of a building. Although it is common knowledge that the presence and activity of building occupants have a significant impact ...

2011-07-01

224

Support vector machines for nuclear reactor state estimation  

Energy Technology Data Exchange (ETDEWEB)

Validation of nuclear power reactor signals is often performed by comparing signal prototypes with the actual reactor signals. The signal prototypes are often computed based on empirical data. The implementation of an estimation algorithm which can make predictions on limited data is an important issue. A new machine learning algorithm called support vector machines (SVMS) recently developed by Vladimir Vapnik and his coworkers enables a high level of generalization with finite high-dimensional data. The improved generalization in comparison with standard methods like neural networks is due mainly to the following characteristics of the method. The input data space is transformed into a high-dimensional feature space using a kernel function, and the learning problem is formulated as a convex quadratic programming problem with a unique solution. In this paper the authors have applied the SVM method for data-based state estimation in nuclear power reactors. In ...

2000-02-14

225

Species differences in anxiety-related responses in male prairie and meadow voles: the effects of social isolation.  

Science.gov (United States)

Prairie (Microtus ochrogaster) and meadow voles (M. pennsylvanicus) are closely related species that differ in life strategy and social behaviors, and thus provide an excellent comparative model for the study of neuronal and hormonal mechanisms underlying behavior. In the present study using the elevated plus maze (EPM) test, we found that male prairie voles entered the open arms of the EPM more and remained there longer, and showed a higher level of overall locomotor activity than did male meadow voles. In addition, two weeks of social isolation induced an increase in open arm entries in prairie, but not meadow, voles. Prairie voles also had a higher level of circulating corticosterone compared to meadow voles, and the EPM test increased circulating corticosterone in prairie voles. Finally, social isolation coupled with the EPM test influenced Fos-immunoreactive expression in several brain areas, including the medial preoptic area, ventromedial hypothalamus, amygdala, and prefrontal ...

2005-08-22

226

Non-isothermal oxidation of ceramic nanocomposites using the example of Ti-Si-C-N powder: Kinetic analysis method  

Energy Technology Data Exchange (ETDEWEB)

A method of kinetic analysis applicable to non-isothermal oxidation processes of ceramic nanocomposites is presented using Ti-Si-C-N powder as the substrate. The nanoparticle size and phase composition were determined using high-resolution transmission electron microscopy and X-ray diffraction (XRD). Thermogravimetric measurements were carried out for powder samples in dry air in the temperature range 298-1770 K. The following heating rates were applied: 3, 5, 10, 20 K min{sup -1}. Mass spectrometry was used to analyze gaseous oxidation products and solid products were identified by the XRD technique. The Coats-Redfern equation was applied for the kinetic analysis. For each stage of the oxidation kinetic models, the best accuracy was achieved using a series of criteria, and then the A and E parameters of the Arrhenius equations were estimated. Both linear regression and artificial neural networks were applied in testing kinetic models.

2008-08-15

227

Nature inspired artificial intelligence based adaptive traffic flow distribution in computer network  

CERN Document Server

Because of the stochastic nature of traffic requirement matrix, it is very difficult to get the optimal traffic distribution to minimize the delay even with adaptive routing protocol in a fixed connection network where capacity already defined for each link. Hence there is a requirement to define such a method, which could generate the optimal solution very quickly and efficiently. This paper presenting a new concept to provide the adaptive optimal traffic distribution for dynamic condition of traffic matrix using nature based intelligence methods. With the defined load and fixed capacity of links, average delay for packet has minimized with various variations of evolutionary programming and particle swarm optimization. Comparative study has given over their performance in terms of converging speed. Universal approximation capability, the key feature of feed forward neural network has applied to predict the flow distribution on each link to minimize the average ...

2010-01-01

228

Modeling of electricity consumption in the Asian gaming and tourism center - Macao SAR, People's Republic of China  

Energy Technology Data Exchange (ETDEWEB)

The use of electricity is indispensable to modern life. As Macao Special Administrative Region becomes a gaming and tourism center in Asia, modeling the consumption of electricity is critical to Macao's economic development. The purposes of this paper are to conduct an extensive literature review on modeling of electricity consumption, and to identify key climatic, demographic, economic and/or industrial factors that may affect the electricity consumption of a country/city. It was identified that the five factors, namely temperature, population, the number of tourists, hotel room occupancy and days per month, could be used to characterize Macao's monthly electricity consumption. Three selected approaches including multiple regression, artificial neural network (ANN) and wavelet ANN were used to derive mathematical models of the electricity consumption. The accuracy of these models was assessed by using the mean squared error (MSE), the mean ...

2008-05-15

229

Maintenance and regulation of extracellular volume and the ion environment in Drosophila larval nerves.  

Science.gov (United States)

In mammals and insects, paracellular blood barriers isolate the nervous system from the rest of the animal. Glia and accessory cells of the nervous system use pumps, channels, cotransporters, and exchangers collectively to maintain the extracellular ion environment and osmotic balance in the nervous system. At present, the molecular mechanisms that regulate this process remain unclear. In humans, loss of extracellular ion and volume regulation in the nervous system poses serious health threats. Drosophila is a model genetic organism with a proven track record for uncovering molecular mechanisms relevant to human health and disease. Here, we review what is known about extracellular ion and volume regulation in larval abdominal nerves, present some new data about the impact of neural activity on the extracellular environment, and relate the findings to mammalian systems. Homologies have been found at the level of morphology, physiology, molecular mechanisms, and ...

2011-02-08

230

Machine vision  

Energy Technology Data Exchange (ETDEWEB)

To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human learning patterns. These networks and their hardware implementations (neurocomputers) show a great deal ...

1989-06-01

231

Lead content of dried films of domestic paints currently sold in Nigeria  

Energy Technology Data Exchange (ETDEWEB)

Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high lead levels in existing housing and if detected, intervention programs for eliminating risk of exposure should be developed in addition to measures to ...

2007-12-15

232

Investigating long-range correlation properties in EEG during complex cognitive tasks  

Energy Technology Data Exchange (ETDEWEB)

Previous work shows the presence of scale invariance and long-range correlations in ongoing and spontaneous activity of large scale brain responses (i.e. EEG), and such scaling behavior can also be modulated by simple sensory stimulus. However, little is known whether such alteration but not destruction in scaling properties also occurs during complex cognitive processing and if neuroplasticity plays any role in mediating such changes. In this study, we addressed these issues by investigating scaling properties of multivariate EEG signals obtained from two broad groups - artists and non-artists - while they performed complex tasks of perception and mental imagery of visual art objects. We found that brain regions showing increased correlation properties from rest were similar for both tasks, suggesting that brain networks responsible for visual perception are reactivated for mental imagery. Further, we observed that the two groups could be differentiated by scaling exponents and an ...

2009-11-30

233

Imaging Ewing's sarcoma  

International Nuclear Information System (INIS)

Ewing's sarcoma is a highly malignant neoplasm of the bone whose origin is still uncertain. A strong relationship exists between Ewing's sarcoma and tumors of neural origin (Ewing family of tumors). Ewing's sarcoma must be distinguished from other round-cell tumors like lymphoma and neuroblastoma and also must be differentiated from osteogenic sarcomas. On plain radiographs, Ewing's sarcoma appears as a lytic or mixed lytic-sclerotic, rarely as predominantly sclerotic lesion with margins Lodwick grade III. It is located primarily in the diaphyseal and metadiaphyseal regions of the long bones of the lower extremities. A large soft tissue tumor is usually present. Magnetic resonance imaging is the imaging modality of choice to evaluate the extent of the primary lesion, to monitor the response to neoadjuvant chemotherapy and to follow up non-resected Ewing's sarcomas. Bone scintigraphy is necessary to detect skeletal metastasis, and "2"0"1thallium scanning has been ...

1998-06-01

234

Identification method for gas-liquid two-phase flow regime based on singular value decomposition and least square support vector machine  

International Nuclear Information System (INIS)

Aiming at the non-stationary characteristics of differential pressure fluctuation signals of gas-liquid two-phase flow, and the slow convergence of learning and liability of dropping into local minima for BP neural networks, flow regime identification method based on Singular Value Decomposition (SVD) and Least Square Support Vector Machine (LS-SVM) is presented. First of all, the Empirical Mode Decomposition (EMD) method is used to decompose the differential pressure fluctuation signals of gas-liquid two-phase flow into a number of stationary Intrinsic Mode Functions (IMFs) components from which the initial feature vector matrix is formed. By applying the singular vale decomposition technique to the initial feature vector matrixes, the singular values are obtained. Finally, the singular values serve as the flow regime characteristic vector to be LS-SVM classifier and flow regimes are identified by the output of the classifier. The identification result of four ...

2007-12-01

235

Fuzzy logic of Aristotelian forms  

Energy Technology Data Exchange (ETDEWEB)

Model-based approaches to pattern recognition and machine vision have been proposed to overcome the exorbitant training requirements of earlier computational paradigms. However, uncertainties in data were found to lead to a combinatorial explosion of the computational complexity. This issue is related here to the roles of a priori knowledge vs. adaptive learning. What is the a-priori knowledge representation that supports learning? I introduce Modeling Field Theory (MFT), a model-based neural network whose adaptive learning is based on a priori models. These models combine deterministic, fuzzy, and statistical aspects to account for a priori knowledge, its fuzzy nature, and data uncertainties. In the process of learning, a priori fuzzy concepts converge to crisp or probabilistic concepts. The MFT is a convergent dynamical system of only linear computational complexity. Fuzzy logic turns out to be essential for reducing the combinatorial complexity to linear one. I ...

1996-12-31

236

Functional MRI of the visual cortex and visual testing in patients with previous optic neuritis.  

DEFF Research Database (Denmark)

The volume of cortical activation as detected by functional magnetic resonance imaging (fMRI) in the visual cortex has previously been shown to be reduced following optic neuritis (ON). In order to understand the cause of this change, we studied the cortical activation, both the size of the activated area and the signal change following ON, and compared the results with results of neuroophthalmological testing. We studied nine patients with previous acute ON and 10 healthy persons served as controls using fMRI with visual stimulation. In addition to a reduced activated volume, patients showed a reduced blood oxygenation level dependent (BOLD) signal increase and a greater asymmetry in the visual cortex, compared with controls. The volume of visual cortical activation was significantly correlated to the result of the contrast sensitivity test. The BOLD signal increase correlated significantly to both the results of the contrast sensitivity test and to the Snellen visual acuity. Our ...

2002-01-01

237

Enhanced Genetic Algorithm approach for Solving Dynamic Shortest Path Routing Problems using Immigrants and Memory Schemes  

CERN Document Server

In Internet Routing, the static shortest path (SP) problem has been addressed using well known intelligent optimization techniques like artificial neural networks, genetic algorithms (GAs) and particle swarm optimization. Advancement in wireless communication lead more and more mobile wireless networks, such as mobile networks [mobile ad hoc networks (MANETs)] and wireless sensor networks. Dynamic nature of the network is the main characteristic of MANET. Therefore, the SP routing problem in MANET turns into dynamic optimization problem (DOP). Here the nodes ae made aware of the environmental condition, thereby making it intelligent, which goes as the input for GA. The implementation then uses GAs with immigrants and memory schemes to solve the dynamic SP routing problem (DSPRP) in MANETS. In our paper, once the network topology changes, the optimal solutions in the new environment can be searched using the new immigrants or the useful information stored in the ...

2011-01-01

238

Cholinergic systems in brain development and disruption by neurotoxicants: nicotine, environmental tobacco smoke, organophosphates  

International Nuclear Information System (INIS)

Acetylcholine and other neurotransmitters play unique trophic roles in brain development. Accordingly, drugs and environmental toxicants that promote or interfere with neurotransmitter function evoke neurodevelopmental abnormalities by disrupting the timing or intensity of neurotrophic actions. The current review discusses three exposure scenarios involving acetylcholine systems: nicotine from maternal smoking during pregnancy, exposure to environmental tobacco smoke (ETS), and exposure to the organophosphate insecticide, chlorpyrifos (CPF). All three have long-term, adverse effects on specific processes involved in brain cell replication and differentiation, synaptic development and function, and ultimately behavioral performance. Many of these effects can be traced to the sequence of cellular events surrounding the trophic role of acetylcholine acting on its specific cellular receptors and associated signaling cascades. However, for chlorpyrifos, additional noncholinergic mechanisms ...

2004-07-15

239

5,10 Methylenetetrahydrofolate reductase genetic polymorphism as a risk factor for neural tube defects  

Science.gov (United States)

Persons with a thermolabile form of the enzyme 5,10 methylenetetrahydrofolate reductase (MTHFR) have reduced enzyme activity and increased plasma homocysteine which can be lowered by supplemental folic acid. Thermolability of the enzyme has recently been shown to be caused by a common mutation (677C{sup {r_arrow}}T) in the MTHFR gene. We studied 41 fibroblast cultures from NTD-affected fetuses and compared their genotypes with those of 109 blood specimens from individuals in the general population. 677C{sup {r_arrow}}T homozygosity was associated with a 7.2 fold increased risk for NTDs (95% confidence interval: 1.8-30.3; p value: 0.001). These preliminary data suggest that the 677C{sup {r_arrow}}T polymorphism of the MTHFR gene is a risk factor for spina bifida and anencephaly that may provide a partial biologic explanation for why folic acid prevents these types of NTD. 13 refs., 1 fig., 1 tab.

1996-06-28

240

In-situ measurement of epithelial tissue optical properties: Development and implementation of diffuse reflectance spectroscopy techniques  

Science.gov (United States)

Cancer is a severe threat to human health. Early detection is considered the best way to increase the chance for survival. While the traditional cancer detection method, biopsy, is invasive, noninvasive optical diagnostic techniques are revolutionizing the way that cancer is diagnosed. Reflectance spectroscopy is one of these optical spectroscopy techniques showing promise as a diagnostic tool for pre-cancer detection. When a neoplasia occurs in tissue, morphologic and biochemical changes happen in the tissue, which in turn results in the change of optical properties and reflectance spectroscopy. Therefore, a pre-cancer can be detected by extracting optical properties from reflectance spectroscopy. This dissertation described the construction of a fiberoptic based reflectance system and the development of a series of modeling studies. This research is aimed at establishing an improved understanding of the optical properties of mucosal tissues by analyzing reflectance signals at ...

2009-01-01

241

Condition monitoring and thermoeconomic optimization of operation for a hybrid plant using artificial neural networks; Tillstaandsoevervakning och termoekonomisk driftoptimering av en hybridanlaeggning med artificiella neurala naetverk  

Energy Technology Data Exchange (ETDEWEB)

The project aim is to model the hybrid plant at Vaesthamnsverket in Helsingborg using artificial neural networks (ANN) and integrating the ANN models, for online condition monitoring and thermoeconomic optimization, at Vaesthamnsverket. The definition of a hybrid plant is that it uses more than one fuel, in this case a natural gas fuelled gas turbine with heat recovery steam generator (HRSG) and a biomass fuelled steam boiler with steam turbine. The project is a continuation of previous projects where ANN training was done with operational data from the plant. The ANN models have, if required, been updated to better suit the purpose of this project. The thermoeconomic optimization takes into account current electricity prices, taxes, fuel prices etc. and calculates the current production cost along with the 'predicted' production cost. The tool also has a built in feature of predicting when a compressor wash is economically beneficial. The user ...

2007-12-15

242

World review of ozone forecasting methods and roles; Prevision des episodes d`ozone: etat de l`art dans le monde  

Energy Technology Data Exchange (ETDEWEB)

The growing concern of the population with regards to the problem of atmospheric pollution has induced a change in the role of air quality monitoring networks, especially those monitoring air pollution in large cities which suffer from summer smog. The population is no longer satisfied with real-time measurements but wants to be warmed of high pollutants concentrations in advance. Some countries have been forecasting air pollution, and especially ozone, for a large number of years. Although most of them use statistical models based on the analyses of past conditions which induced high pollution episodes, some predict ozone levels using only their knowledge of the meteorological situation. Nowadays two trends appear regarding ozone forecasting: either very basic statistical methods, such as regression, or more sophisticated ones, such as neural networks. The paper then reviews several behaviours common to most forecasting models: the uncertainly due to the great ...

1997-04-01

243

Sex and species differences in tyrosine hydroxylase-synthesizing cells of the rodent olfactory extended amygdala.  

Science.gov (United States)

The bed nucleus of the stria terminalis (BST) and the medial amygdala (MeA) are anatomically connected sites necessary for chemosensory regulation of social behaviors in rodents. Prairie voles (Microtus ochrogaster) are a valuable model for studying the neural regulation of social behaviors because, unlike many other rodents, they are gregarious, pair bond after copulating, and are biparental. We herein describe sex and species differences in immunoreactivity for tyrosine hydroxylase (TH), the rate-limiting enzyme for catecholamine synthesis, in the BST and MeA. Virgin male prairie voles had a large number of TH-immunoreactive cells in areas analogous to the rat principal nucleus of the BST (pBST) and the posterodorsal medial amygdala (MeAPd). Virgin female prairie voles had far fewer TH-immunoreactive cells in these sites ( approximately 17% of the number of cells as males in the pBST, approximately 35% of the number of cells in the MeAPd). A few TH-immunoreactive ...

2007-01-01

244

Restudy of acid-extractable hydrocarbon data from surface geochemical survey in the Yimeng Uplift of the Ordos Basin, China: Improvement of geochemical prospecting for hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Two geochemical surveys were conducted in 1992 and 2000 respectively in the Yimeng Uplift of the Ordos Basin, China. The earlier survey grid had 1 x 5km spacing and the later survey grid had 0.5 x 0.5km spacing. The acid-extractable hydrocarbons of both surveys show similar geochemical trends. However, the anomalies obtained with traditional statistical methods do not correlate with existing oil/gas fields. This study reveals two problems in the data and their processing. The first one is interference caused by the variation of soil composition. We applied a wavelet-analysis-based method to eliminate this interference in the data of the later survey. The second is that micro-seepage anomalies did not identify existing oil/gas fields and seepage anomalies related with faults had not been previously recognized. We modified the logic multiplication cluster analysis and applied a multi-fractal model and a back propagation artificial neural network to recognize these ...

2006-06-15

245

Propolis derivatives inhibit the systemic inflammatory response and protect hepatic and neuronal cells in acute septic shock  

Scientific Electronic Library Online (English)

Abstract in english BACKGROUND: Severe pathogenic infection triggers excessive release of cytokines as part of the massive inflammatory response associated with septic shock. OBJECTIVES: To investigate the protective effect of caffeic acid phenethye ester (CAPE) against lipopolysaccharide (LPS) induced endotoxemia, hepatic and neuronal damage and the associated systemic inflammatory response (SIR). METHODS: Fifty male Wister rats were divided into: control, LPS, and CAPE+LPS groups. Plasma c (more) oncentrations of various cytokines, including TNF-?, IL-1?, IL-1?, IL-6, IL-4, IL-10, and sICAM-1 were evaluated. In addition, the histopathological changes in the hepatic and neural cells were assessed. RESULTS: The LPS group showed high inflammatory cytokines and sICAM-1 levels reflecting the presence of SIR. Hepatocyte necrosis, apoptosis, extensive hemorrhage and inflammatory cellular infiltration together with brain astrocytes swelling, early neuron injury and ...

2011-08-01

246

Neural node network and model, and method of teaching same  

Energy Technology Data Exchange (ETDEWEB)

The present invention is a fully connected feed forward network that includes at least one hidden layer 16. The hidden layer 16 includes nodes 20 in which the output of the node is fed back to that node as an input with a unit delay produced by a delay device 24 occurring in the feedback path 22 (local feedback). Each node within each layer also receives a delayed output (crosstalk) produced by a delay unit 36 from all the other nodes within the same layer 16. The node performs a transfer function operation based on the inputs from the previous layer and the delayed outputs. The network can be implemented as analog or digital or within a general purpose processor. Two teaching methods can be used: (1) back propagation of weight calculation that includes the local feedback and the crosstalk or (2) more preferably a feed forward gradient decent which immediately follows the output computations and which also includes the local feedback and the crosstalk. Subsequent to the gradient ...

1995-01-01

247

Magnetic field exposures for UK live-line workers  

International Nuclear Information System (INIS)

Dosimetry is evaluated for live-line workers exposed to 50 Hz non-uniform magnetic fields from typical high-voltage transmission lines in the United Kingdom. The configurations involve twin-, triple- and quadruple-conductor transmission line bundles. Scenarios include three worker postures for the twin and triple bundles, and four postures for the quadruple bundle. The postures are selected to simulate worst case scenarios representative of work practices and result in highest values of dosimetric measures in critical organs. Only single-phase bundles are considered, as adjacent bundles of differing phase result only in a small reduction of the dosimetric measures. Reported data include various measures of the electric field and current density induced in tissues, as well as of the current density averaged over 1 cm"2 areas normal to the current flow. A value of this latter quantity of 10 mA m"-"2 is suggested as a threshold for neural tissue in the UK and ...

2002-04-01

248

Improved eddy-current inspection for steam generator tubing  

International Nuclear Information System (INIS)

Computer programs have been written to allow the analysis of different types of eddy-current probes and their performance under different steam generators test conditions. The probe types include the differential bobbin probe, the absolute bobbin probe, the pancake probe and the reflection probe. The generator test conditions include tube supports, copper deposits, magnetite deposits, denting, wastage, pitting, cracking, and intergranular attack. These studies are based mostly on computed values, with the limited number of test specimens available used to verify the computed results. The instrument readings were computed for a complete matrix of the different test conditions, and then the test conditions determined as a function of the readings by a least-squares technique. A comparison was made of the errors in fit and instrument drift for the different probe types. The computations of the change in instrument reading due to the defects have led to an inversion technique in which the ...

1990-03-01

249

Fluoroscopic tumor tracking for image-guided lung cancer radiotherapy  

Energy Technology Data Exchange (ETDEWEB)

Accurate lung tumor tracking in real time is a keystone to image-guided radiotherapy of lung cancers. Existing lung tumor tracking approaches can be roughly grouped into three categories: (1) deriving tumor position from external surrogates; (2) tracking implanted fiducial markers fluoroscopically or electromagnetically; (3) fluoroscopically tracking lung tumor without implanted fiducial markers. The first approach suffers from insufficient accuracy, while the second may not be widely accepted due to the risk of pneumothorax. Previous studies in fluoroscopic markerless tracking are mainly based on template matching methods, which may fail when the tumor boundary is unclear in fluoroscopic images. In this paper we propose a novel markerless tumor tracking algorithm, which employs the correlation between the tumor position and surrogate anatomic features in the image. The positions of the surrogate features are not directly tracked; instead, we use principal component analysis of regions ...

2009-02-21

250

Disorders of brain development and phakomatosis  

International Nuclear Information System (INIS)

Full text: Disorders of brain development and phakomatosis are resulting from disturbed embryonic-foetal development One third of all major embryological anomalies involve CNS, and over 2000 different anomalies have been described. Anomalies of the brain often cause foetal and neonatal death, and mental and physical retardation in pediatric group. The majority of disorders of brain development and phakomatosis are idiopathic, and most of them are not hereditary or familial. Ultrasonography plays the important role in screening foetal and neonatal brain, but after closure of fontanels it is difficult to find the acoustic window. CT has limited contrast resolution, and disadvantage exposing infant to ionizing radiation. It is helpful to demonstrate the presence of calcifications. MR imaging has proved to be a diagnostic tool of major importance in children with disorders of brain development and phakomatosis. The excellent grey/white matter differentiation and multiplanar imaging ...

251

Changes in the extracellular matrix and glycosaminoglycan synthesis during the initiation of regeneration in adult newt forelimbs  

International Nuclear Information System (INIS)

The extracellular matrix (ECM) of the distal tissues in a newt limb stump is completely reorganized in the 2-3-week period following amputation. In view of numerous in vitro studies showing that extracellular material influences cellular migration and proliferation, it is likely that the changes in the limb's ECM are important activities in the process leading to regeneration of such limbs. Using biochemical, autoradiographic, and histochemical techniques we studied temporal and spatial differences in the synthesis of glycosaminoglycans (GAGs) during the early, nerve-dependent phase of limb regeneration. Hyaluronic acid synthesis began with the onset of tissue dedifferentiation, became maximal within 1 weeks, and continued throughout the period of active cell proliferation. Chondroitin sulfate synthesis began somewhat later, increased steadily, and reached very high levels during chondrogenesis. During the first 10 days after amputation, distributions of sulfated and nonsulfated GAGs ...

1986-01-01

252

Carcinogenicity of Black Rock Harbor sediment to the eastern oyster and trophic transfer of Black Rock Harbor carcinogens from the blue mussel to the winter flounder  

Energy Technology Data Exchange (ETDEWEB)

The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed ...

1991-01-01

253

Brain mechanisms supporting the modulation of pain by mindfulness meditation.  

Science.gov (United States)

The subjective experience of one's environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a nonevaluative representation of sensory events. To better understand how meditation influences the sensory experience, we used arterial spin labeling functional magnetic resonance imaging to assess the neural mechanisms by which mindfulness meditation influences pain in healthy human participants. After 4 d of mindfulness meditation training, meditating in the presence of noxious stimulation significantly reduced pain unpleasantness by 57% and pain intensity ratings by 40% when compared to rest. A two-factor repeated-measures ANOVA was used to identify interactions between meditation and pain-related brain activation. Meditation reduced pain-related activation of the contralateral primary somatosensory cortex. Multiple regression analysis was used to ...

2011-04-01

254

A study of relative regional cerebral blood flow using N-isopropyl-p-["1"2"5I]-iodoamphetamine ("1"2"5I-IMP) in carbon monoxide exposed rats  

International Nuclear Information System (INIS)

The influence of carbon monoxide (CO) exposure on regional cerebral blood flow (r-CBF) in rat brain was studied using autoradiography and "1"2"5I-IMP. Fuji computed radiography (FCR) was used to obtain improved autoradiograms in this study. R-CBF was determined in a relative measure by calculating hippocampus/cortex and putamen/cortex ratios of RI accumulation from the autoradiogram using a densitometer. Comparison of autoradiograms with pathological findings in the area of the hippocampus and putamen yield the following results. In the animals that were exposed to 6400 ppm or 10000 ppm of CO for 30 minutes, and then were followed up for 2 weeks without further exposure, r-CBF was decreased but no pathological changes occurred. In the animals that were exposed to 6400 ppm or 10000 ppm of CO, and then were followed up for 4 weeks without further exposure, pathological changes appeared. In animals exposed to 3200 ppm of CO, the r-CBF tended to recover after 4 weeks. Furthermore, ...

255

A study of relative regional cerebral blood flow using N-isopropyl-p-( sup 125 I)-iodoamphetamine ( sup 125 I-IMP) in carbon monoxide exposed rats  

Energy Technology Data Exchange (ETDEWEB)

The influence of carbon monoxide (CO) exposure on regional cerebral blood flow (r-CBF) in rat brain was studied using autoradiography and {sup 125}I-IMP. Fuji computed radiography (FCR) was used to obtain improved autoradiograms in this study. R-CBF was determined in a relative measure by calculating hippocampus/cortex and putamen/cortex ratios of RI accumulation from the autoradiogram using a densitometer. Comparison of autoradiograms with pathological findings in the area of the hippocampus and putamen yield the following results. In the animals that were exposed to 6400 ppm or 10000 ppm of CO for 30 minutes, and then were followed up for 2 weeks without further exposure, r-CBF was decreased but no pathological changes occurred. In the animals that were exposed to 6400 ppm or 10000 ppm of CO, and then were followed up for 4 weeks without further exposure, pathological changes appeared. In animals exposed to 3200 ppm of CO, the r-CBF tended to recover after 4 weeks. Furthermore, ...

1990-11-01

256

Petrophysical Analysis and Geographic Information System for San Juan Basin Tight Gas Reservoirs  

Energy Technology Data Exchange (ETDEWEB)

The primary goal of this project is to increase the availability and ease of access to critical data on the Mesaverde and Dakota tight gas reservoirs of the San Juan Basin. Secondary goals include tuning well log interpretations through integration of core, water chemistry and production analysis data to help identify bypassed pay zones; increased knowledge of permeability ratios and how they affect well drainage and thus infill drilling plans; improved time-depth correlations through regional mapping of sonic logs; and improved understanding of the variability of formation waters within the basin through spatial analysis of water chemistry data. The project will collect, integrate, and analyze a variety of petrophysical and well data concerning the Mesaverde and Dakota reservoirs of the San Juan Basin, with particular emphasis on data available in the areas defined as tight gas areas for purpose of FERC. A relational, geo-referenced database (a geographic information system, or GIS) ...

2008-10-01

257

Research and Development Program in Reactor Diagnostics and Monitoring with Neutron Noise Methods. Stage 13. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report describes the results obtained during Stage 13 of a long-term research and development program concerning the development of diagnostics and monitoring methods for nuclear reactors. A brief proposal for the continuation of this program in Stage 14 is also given at the end of the report. The program executed in Stage 13 consists of three parts and the work performed in each part is summarized below. 1. Study of criticality, neutron kinetics and neutron noise in molten salt reactors (MSR). Although the original goal of the investigations of the MSR in Stage 13 was to calculate the neutron noise induced by the fluctuations of the fuel temperature, the study, solution and interpretation of the static problem, as well as to define an approximate version of the point kinetic approximation was necessary to perform. As it turned out, these tasks in themselves were more involved, and also very edifying, to solve. Hence, in this report, we confine the study of the reactor physics of ...

2008-06-15

258

MULTICOMPONENT SEISMIC ANALYSIS AND CALIBRATION TO IMPROVE RECOVERY FROM ALGAL MOUNDS: APPLICATION TO THE ROADRUNNER/TOWAOC AREA OF THE PARADOX BASIN, UTE MOUNTAIN UTE RESERVATION, COLORADO  

Energy Technology Data Exchange (ETDEWEB)

This report describes the results made in fulfillment of contract DE-FG26-02NT15451, ''Multicomponent Seismic Analysis and Calibration to Improve Recovery from Algal Mounds: Application to the Roadrunner/Towaoc Area of the Paradox Basin, Ute Mountain Ute Reservation, Colorado''. Optimizing development of highly heterogeneous reservoirs where porosity and permeability vary in unpredictable ways due to facies variations can be challenging. An important example of this is in the algal mounds of the Lower and Upper Ismay reservoirs of the Paradox Basin in Utah and Colorado. It is nearly impossible to develop a forward predictive model to delineate regions of better reservoir development, and so enhanced recovery processes must be selected and designed based upon data that can quantitatively or qualitatively distinguish regions of good or bad reservoir permeability and porosity between existing well control. Recent advances in seismic acquisition and ...

2003-07-10