WorldWideScience
1

Distributed Beamforming in Wireless Multiuser Relay-Interference Networks with Quantized Feedback  

CERN Document Server

We study quantized beamforming in wireless amplify-and-forward relay-interference networks with any number of transmitters, relays, and receivers. We design the quantizer of the channel state information to minimize the probability that at least one receiver incorrectly decodes its desired symbol(s). Correspondingly, we introduce a generalized diversity measure that encapsulates the conventional one as the first-order diversity. Additionally, it incorporates the second-order diversity, which is concerned with the transmitter power dependent logarithmic terms that appear in the error rate expression. First, we show that, regardless of the quantizer and the amount of feedback that is used, the relay-interference network suffers a second-order diversity loss compared to interference-free networks. Then, two different quantization schemes are studied: First, using a ...

2010-01-01

2

The Generalized Quantization Schemes for Games and its Application to Quantum Information  

CERN Document Server

Theory of quantum games is relatively new to the literature and its applications to various areas of research are being explored. It is a novel interpretation of strategies and decisions in quantum domain. In the earlier work on quantum games considerable attention was given to the resolution of dilemmas present in corresponding classical games. Two separate quantum schemes were presented by Eisert et al. and Marinatto and Weber to resolve dilemmas in Prisoners' Dilemma and Battle of Sexes games respectively. However for the latter scheme it was argued that dilemma was not resolved. We have modified the quantization scheme of Marinatto and Weber to resolve the dilemma. We have developed a generalized quantization scheme for two person non-zero sum games which reduces to the existing schemes under certain conditions. Applications of this generalized quantization scheme to quantum information theory are ...

2010-01-01

3

Quantum information approach to the ultimatum game  

CERN Document Server

The paper is devoted to quantization of extensive games with the use of both the Marinatto-Weber and the Eisert-Wilkens-Lewenstein concept of quantum game. We revise the current conception of quantum ultimatum game and we show why the proposal is unacceptable. To support our comment, we present the new idea of the quantum ultimatum game. Our scheme also makes a point of departure for a protocol to quantize extensive games.

2011-01-01

4

A Fast Audio Clustering Using Vector Quantization and Second Order Statistics  

CERN Document Server

This paper describes an effective unsupervised speaker indexing approach. We suggest a two stage algorithm to speed-up the state-of-the-art algorithm based on the Bayesian Information Criterion (BIC). In the first stage of the merging process a computationally cheap method based on the vector quantization (VQ) is used. Then in the second stage a more computational expensive technique based on the BIC is applied. In the speaker indexing task a turning parameter or a threshold is used. We suggest an on-line procedure to define the value of a turning parameter without using development data. The results are evaluated using 10 hours of audio data.

2010-01-01

5

Cooperative Strategies for Simultaneous and Broadcast Relay Channels  

CERN Document Server

Consider the simultaneous relay channel which consists of a set of relay channels where the source wishes to transmit common and private information to each of the destinations. This problem is recognized as being equivalent to that of sending common and private information to several destinations in presence of helper relays where each channel outcome becomes a branch of the broadcast relay channel (BRC). Cooperative schemes and capacity region for a set of two relay channels are investigated. The proposed coding schemes, based on Decode-and-Forward (DF) and Compress-and-Forward (CF), must be capable of transmitting information simultaneously to all destinations in such set. Inner bounds on the capacity region of the general BRC are based on three cases. First the channels from source-to-relays of ...

2011-01-01

6

NAME=\\  

Wastenet

... HOWEVER, 27 FREE TV CHANNELS ARE PROVIDED VIA UCLAN'S NETWORK TO YOUR COMPUTER LAPTOP Visit http://www.freewiretv.com for more informtion on the free channels provided and options to purchase further channels. You will still need a licence to view so visit : http://www.tvlicensing.co.uk/information/students.jsp for more informaton. Every bedroom in our accommodation also has a ...

7

Quantum secure direct communication by EPR pairs and entanglement swapping  

Science.gov (United States)

We present a quantum secure direct communication scheme achieved by swapping quantum entanglement. In this scheme a set of ordered Einstein-Podolsky-Rosen (EPR) pairs is used as a quantum information channel for sending secret messages directly. After insuring the safety of the quantum channel, the sender Alice encodes the secret messages directly by applying a series local operations on her particle sequences according to their stipulation. Using three EPR pairs, three bits of secret classical information can be faithfully transmitted from Alice to remote Bob without revealing any information to a potential eavesdropper. By both Alice and Bob's GHZ state measurement results, Bob is able to read out the encoded secret messages directly. The protocol is completely secure if perfect quantum channel is used, because there is not a transmission of the qubits ...

2004-03-01

8

Approximate MIMO Iterative Processing with Adjustable Complexity Requirements  

CERN Document Server

Targeting always the best achievable bit error rate (BER) performance in iterative receivers operating over multiple-input multiple-output (MIMO) channels may result in significant waste of resources, especially when the achievable BER is orders of magnitude better than the target performance (e.g., under good channel conditions and at high signal-to-noise ratio (SNR)). In contrast to the typical iterative schemes, a practical iterative decoding framework that approximates the soft-information exchange is proposed which allows reduced complexity sphere and channel decoding, adjustable to the transmission conditions and the required bit error rate. With the proposed approximate soft information exchange the performance of the exact soft information can still be reached with significant complexity gains.

2011-01-01

9

NAME=\\  

Wastenet

... Possibilities for summer activities become better, but socioeconomic factors such as age-structure may weaken the positive impact. Several research needs related to recreation and tourism were identified. The Finnish tourism industry seems to need more detailed and spatially informed scenarios concerning climate change and more information on its impacts on the different activities in the tourism sector. Also communication channels seem to need more attention. More information is ...

10

Quantum secure direct communication scheme using a W state and teleportation  

International Nuclear Information System (INIS)

A theoretical scheme for quantum secure direct communication (QSDC) is proposed, where a three-qubit symmetric W state functions as a quantum channel. Two legitimate communicators can transmit their secret information by using quantum teleportation and local measurements.

2006-11-01

11

Does the online channel pay? A comparison of online versus offline information search on physical store spend  

British Library Electronic Table of Contents (United Kingdom)

The Internet has transformed consumer behaviour, particularly the manner in which consumers search for information prior to making a purchase. However, we know relatively little about the relationship between consumer information search strategies prior to visiting a physical retail store and the amount of money spent on product purchases. This raises an important question for retailers; does the online channel pay? We test this notion in a study of 1275 consumers across the four retail categories of Clothing and Footwear, Beauty and Skincare, DIY Hardware, and Kitchen and Bathroom Renovations. We find that in all categories, except for Clothing and Footwear, consumers who used the Internet to search for product information prior to making a physical store purchase, spent more money when p...

2010-01-01

12

Influencing citizen behavior: Experiences from multichannel marketing pilot projects  

British Library Electronic Table of Contents (United Kingdom)

Information technology allows national and local governments to satisfy the needs of citizens in a cost effective way. Unfortunately, citizens still tend to prefer traditional, more costly channels, such as the front desk, phone and mail. Through pilot projects government agencies attempt to influence this behavior of citizens, directing them towards the online channel. With this paper we provide insight into the possibility to influence citizens' behavior in the complex landscape of multi-channel service provision. The paper systematically compares five pilot projects using a framework that is based on organizational and marketing literature. The results show that socio-psychological factors are crucial in multi-channel management, much more than the technology itself. We conclude that ci...

2011-01-01

13

Asymptotic Analysis of Double-Scattering Channels  

CERN Document Server

We consider a multiple-input multiple-output (MIMO) multiple access channel (MAC), where the channel between each transmitter and the receiver is modeled by the doubly-scattering channel model. Based on novel techniques from random matrix theory, we derive deterministic approximations of the mutual information, the signal-to-noise-plus-interference-ratio (SINR) at the output of the minimum-mean-square-error (MMSE) detector and the sum-rate with MMSE detection which are almost surely tight in the large system limit. Moreover, we derive the asymptotically optimal transmit covariance matrices. Our simulation results show that the asymptotic analysis provides very close approximations for realistic system dimensions.

2011-01-01

14

Isomorphisms of quantizations via quantization of resolutions  

CERN Document Server

In this paper we prove the existence of isomorphisms between certain non-commutative algebras that are interesting from representation theoretic perspective and arise as quantizations of certain Poisson algebras. We show that quantizations of Kleinian resolutions obtained by three different constructions are isomorphic to each other. The constructions are via symplectic reflection algebras, quantum Hamiltonian reduction, and W-algebras. Next, we prove that parabolic W-algebras in type A are isomorphic to quantum Hamiltonian reductions associated to quivers of type A. Finally, we show that the symplectic reflection algebras for wreath-products of the symmetric group and a Kleinian group are isomorphic to certain quantum Hamiltonian reductions. Our results involving W-algebras are new, while for those dealing with symplectic reflection algebras we just give new proofs. A key ingredient in our proofs is the study of ...

2010-01-01

15

Black hole horizons from within loop quantum gravity  

CERN Document Server

In general relativity, the fields on a black hole horizon are obtained from those in the bulk by pullback and restriction. Similarly, in quantum gravity, the quantized horizon degrees of freedom should result from restricting, or pulling-back, the quantized bulk degrees of freedom. This is not yet fully realized in the - otherwise very successful - quantization of isolated horizons in loop quantum gravity. In this work we outline a setting in which the quantum horizon degrees of freedom are simply components of the quantized bulk degrees of freedom. There is no need to quantize them separately. We present evidence that for a horizon of sphere topology, the resulting horizon theory is remarkably similar to what has been found before.

2011-01-01

16

Precise characterisation of nanochannels in track etched membranes by SAXS and SANS  

Energy Technology Data Exchange (ETDEWEB)

Poster session: Abstract is full text. Track membranes are thin polymer foils irradiated by heavy ions. The defects created by the heavy ions are located along the ions trajectory, the track. It is possible to open channels by etching with a chemical agent. These channels are very uniform. Small Angle Scattering (of X rays and neutrons) give global information about the characteristics of the channel shape. As the nanochannels are strictly parallel, an excellent sample orientation is required to obtain interpretable spectra. Then shoulders due to the oscillations of the Bessel function (radial part of the channel shape Fourier transform) are easily seen in the scattered intensity in the PXY data treatment software of SAS spectra allow to determine the channel diameter with its dispersion law, to demonstrate the existence of a wall thickness with a linearly ...

2003-05-01

17

Sexual information seeking on web search engines.  

Science.gov (United States)

Sexual information seeking is an important element within human information behavior. Seeking sexually related information on the Internet takes many forms and channels, including chat rooms discussions, accessing Websites or searching Web search engines for sexual materials. The study of sexual Web queries provides insight into sexually-related information-seeking behavior, of value to Web users and providers alike. We qualitatively analyzed queries from logs of 1,025,910 Alta Vista and AlltheWeb.com Web user queries from 2001. We compared the differences in sexually-related Web searching between Alta Vista and AlltheWeb.com users. Differences were found in session duration, query outcomes, and search term choices. Implications of the findings for sexual information seeking are discussed. PMID:15006171

2004-02-01

18

Boiling flow instabilities in parallel channels with enhanced heat transfer  

International Nuclear Information System (INIS)

During the last two decades, the demand for higher heat transfers in the heat exchangers has kept increasing. These high heat transfer rates can be obtained by using two-phase flows, or heat transfer augmented surfaces, or in some cases, both. Thus, the boiling flows and the associated two-phase flow instabilities have been studied by many investigators. Most of the work in boiling flows has been concentrated on single channel upflow systems or on parallel channel systems with plain heat transfer surfaces. The boiling flow instabilities in multi-channel systems should be covered to a greater extent, studying the effects of various parameters, such as inlet and outlet restriction, mass flow rates, the property variations, heat transfer coefficients, equal and unequal heat inputs on the stability. Also, the mathematical modeling needs to be developed for the parallel channel system to take into account ...

1985-10-01

19

Deterministic secure direct communication using GHZ states and swapping quantum entanglement  

International Nuclear Information System (INIS)

We present a deterministic secure direct communication scheme via entanglement swapping, where a set of ordered maximally entangled three-particle states (GHZ states), initially shared by three spatially separated parties, Alice, Bob and Charlie, functions as a quantum information channel. After ensuring the safety of the quantum channel, Alice and Bob apply a series of local operations on their respective particles according to the tripartite stipulation and the secret message they both want to send to Charlie. By three of Alice, Bob and Charlie's Bell measurement results, Charlie is able to infer the secret messages directly. The secret messages are faithfully transmitted from Alice and Bob to Charlie via initially shared pairs of GHZ states without revealing any information to a potential eavesdropper. Since there is no transmission of the qubits carrying the secret message between any two of them in ...

2005-06-24

20

Full-Rate Full-Diversity Achieving MIMO Precoding with Partial CSIT  

CERN Document Server

In this paper, we consider a $n_t\\times n_r$ multiple-input multiple-output (MIMO) channel subjected to block fading. Reliability (in terms of achieved diversity order) and rate (in number of symbols transmitted per channel use) are of interest in such channels. We propose a new precoding scheme which achieves both full diversity ($n_tn_r$th order diversity) as well as full rate ($n_t$ symbols per channel use) using partial channel state information at the transmitter (CSIT), applicable in MIMO systems including $n_r

2011-01-01

21

Anode Front-End Electronics for the Cathode Strip Chambers of the CMS Endcap Muon Detector  

CERN Document Server

The front-end electronics system for the anode signals of the CMS Endcap Muon cathode strip chambers has about 183000 channels. The purposes of the anode front-end electronics are to acquire precise muon timing information for bunch crossing number identification at the Level-1 muon trigger system and to provide a coarse radial position of the muon track. Each anode channel consists of an input protection network, amplifier, shaper, constant-fraction discriminator, and a programmable delay. The essential parts of the electronics include a 16-channel amplifier-shaper-discriminator ASIC CMP16 and a 16-channel ASIC D16G providing programmable time delay. The ASIC CMP16 was optimized for the large cathode chamber size (up to 3 x 2.5 m2) and for the large input capacitance (up to 200 pf). The ASIC combines low power consumption (30 mW/channel) with good time ...

2005-01-01

22

On Syndrome Decoding for Source Coding Based on Convolutional and Turbo Codes  

CERN Document Server

In source coding, either with or without side information at the decoder, the ultimate performance can be achieved by means of random binning. Structured binning into cosets of performing channel codes has been successfully employed in practical applications. In this letter it is formally shown that various convolutional- and turbo-syndrome decoding algorithms proposed in literature lead in fact to the same estimate. An equivalent implementation is also delineated by directly tackling syndrome decoding as a maximum a posteriori probability problem and solving it by means of iterative message-passing. This solution takes advantage of the exact same structures and algorithms used by the conventional channel decoder for the code according to which the syndrome is formed.

2009-01-01

23

Nuclear design analysis of wolsung-1 CANDU-PHW nuclear generating station  

International Nuclear Information System (INIS)

A combination of computer codes such as LATREP, HWRAXAV and CITATION is utilized in an attempt to analyze the nuclear design characteristics of the CAXDU-PHWR of the Wolsung Unit 1. The major nuclear properties to be computed are the lattice properties of CANDU fuel channel and the core channel power distribution. The computed results are compared with the preliminary safety reports documentation for the Wolsung reactor. The observed discrepancies between our computations and the preliminary safety reports values are discussed in terms of incomplete information on the description of the core configuration in the preliminary safety reports and the different calculation methods. (author).

1978-01-01

24

Quantization in the presence of Gribov ambiguities  

Energy Technology Data Exchange (ETDEWEB)

The non-perturbative validity of covariant BRST-quantization of gauge theories on compact Euclidean space-time manifolds is reviewed. BRST-quantization is related to the construction of a Topological Quantum Field Theory (TQFT) of Witten type on the gauge group. The criterion for the non-perturbative validity of the quantization is that the partition function of the corresponding TQFT does not vanish and that its (equi-variant) BRST-algebra is free of anomalies. I sketch the construction of a TQFT whose partition function is proportional to the generalized Euler-characteristic of the coset space S U (n){sub gauge} / SU(n){sub global} with an associated equi-variant BRST-algebra that manifestly preserves translational symmetry. Some non-perturbative consequences of this approach are discussed. (author)

1999-07-01

25

Fourier duality as a quantization principle  

Energy Technology Data Exchange (ETDEWEB)

The Weyl-Wigner prescription for quantization on Euclidean phase spaces makes essential use of Fourier duality. The extension of this property to more general phase spaces requires the use of Kac algebras, which provide the necessary background for the implementation of Fourier duality on general locally groups. Kac algebras - and the duality they incorporate are consequently examined as candidates for a general quantization framework extending the usual formalism. Using as a test case the simplest non-trivial phase space, the half-plane, it is shown how the structures present in the complete-plane case must be modified. Traces, for example, must be replaced by their noncommutative generalizations - weights - and the correspondence embodied in the Weyl-Wigner formalism is no more complete. Provided the underlying algebraic structure is suitably adapted to each case, Fourier duality is shown to be indeed a very powerful guide to the ...

1996-08-01

26

Media Choice in Environmental Information Dissemination for Solid Waste Management among Policy Formulators and Implementors: A Case Study of Oyo State, Nigeria  

British Library Electronic Table of Contents (United Kingdom)

Environmental information has been described as central to the issues of solid waste management and disposal. This study investigated the availability and accessibility of environmental information to the solid waste policy formulators and implementors with regard to the media/channels used for disseminating environmental information to the public. A descriptive survey design was adopted for the study. A purposive sampling technique was used to select the sample and the method produced 205 respondents that consisted of 185 Policy Implementors and 20 Policy Formulators. A total of 147 cases were finally analyzed, which included 16 Policy Formulators (80% of total sample) and 131 Policy Implementors (71% of total sample). Data collected were analyzed using descriptive statistics such as perc...

2009-01-01

27

Second quantization of fields associated with spin-1 tachyons  

Energy Technology Data Exchange (ETDEWEB)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. 15 refs.

1982-01-01

28

Second quantization of fields associated with spin-1 tachyons  

International Nuclear Information System (INIS)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. (author).

29

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

30

Conductance quantization in ferromagnetic Ni nano-constriction  

Energy Technology Data Exchange (ETDEWEB)

The conductance in ferromagnetic Ni nano-wire is quantized in units of 2e{sup 2}/h in the absence of magnetic field, while the units switch to e{sup 2}/h in the magnetic field. The fractional units of 0.7e{sup 2}/h and 1.4e{sup 2}/h with and without magnetic field appear under the application of high bias-voltage. The spin polarization and bias-voltage play an important role in the electric conduction.

2002-02-01

31

Algebraic description of perturbation theory in quantum electrodynamics  

Energy Technology Data Exchange (ETDEWEB)

An algebraic formulation of the electromagnetic field in which various quantization procedures can be described was chosen to discuss perturbation calculations. It is shown that the Feynman rules and the second order calculation of the self-energy of the electron can be developed on the basis of the Fermi method of quantization. The algebraic approach clarifies the problems in defining the vacuum and other states which are associated with calculations in terms of field algebra operators. It is demonstrated that the vacuum state defined on the field algebra by Schwinger leads to incorrect results in the self-energy calculation.

1982-01-01

32

A_2 Toda theory in reduced WZNW framework and the representations of the W-algebra  

International Nuclear Information System (INIS)

Using the reduced WZNW formulation we analyse the classical W-orbit content of the space of classical solutions of the A_2 Toda theory. We define the quantized Toda field as a periodic primary field of the W-algebra satisfying the quantized equations of motion. We show that this local operator can be constructed consistently only in Hilbert space consisting of the representation corresponding to the minimal models of the W-algebra. (orig.).

1992-10-01

33

Is loop quantization in cosmology unique?  

CERN Document Server

We re-examine the process of loop quantization for flat isotropic models in cosmology. In particular, we contrast different inequivalent `loop quantizations' of these simple models through their respective successes and limitations and assess whether they can lead to any viable physical description. We propose three simple requirements which any such admissible quantum model should satisfy: i) independence from any auxiliary structure, such as a fiducial interval/cell introduced to define the phase space when integrating over non-compact manifolds; ii) existence of a well defined classical limit and iii) provide a sensible "Planck scale" where quantum gravitational effects become manifest. We show that even when it may seem that one can have several possible loop quantizations, these physical requirements considerably narrow down the consistent choices. Apart for the so called improved dynamics of LQC, none of the other ...

2008-01-01

34

Monte Carlo simulations of precise timekeeping in the Milstar communication satellite system  

Science.gov (United States)

The Milstar communications satellite system will provide secure antijam communication capabilities for DOD operations into the next century. In order to accomplish this task, the Milstar system will employ precise timekeeping on its satellites and at its ground control stations. The constellation will consist of four satellites in geosynchronous orbit, each carrying a set of four rubidium (Rb) atomic clocks. Several times a day, during normal operation, the Mission Control Element (MCE) will collect timing information from the constellation, and after several days use this information to update the time and frequency of the satellite clocks. The MCE will maintain precise time with a cesium (Cs) atomic clock, synchronized to UTC(USNO) via a GPS receiver. We have developed a Monte Carlo simulation of Milstar's space segment timekeeping. The simulation includes the effects of: uplink/downlink time transfer noise; satellite crosslink time transfer ...

1995-05-01

35

Experimental demonstration of three-color entanglement  

CERN Document Server

Entanglement is the essential quantum resource for a potential speed-up of information processing, as well as for sophisticated quantum communication. Quantum information networks will be required to convey information from one place to another, by using entangled light beams. Many physical systems are under consideration as building blocks, with different merits and faults, so that hybrid systems are likely to be developed. Here we present an important tool for connecting systems that share no common resonance frequencies: we demonstrate the first direct generation of entanglement among more than two bright beams of light, all of different wavelengths (532.251 nm, 1062.102 nm, and 1066.915 nm). We also observe, for the first time, disentanglement for finite channel losses, the continuous variable counterpart to entanglement sudden death.

2010-01-01

36

An efficient quantum secure direct communication scheme with authentication  

Science.gov (United States)

In this paper an efficient quantum secure direct communication (QSDC) scheme with authentication is presented, which is based on quantum entanglement and polarized single photons. The present protocol uses Einstein-Podolsky-Rosen (EPR) pairs and polarized single photons in batches. A particle of the EPR pairs is retained in the sender's station, and the other is transmitted forth and back between the sender and the receiver, similar to the ``ping-pong'' QSDC protocol. According to the shared information beforehand, these two kinds of quantum states are mixed and then transmitted via a quantum channel. The EPR pairs are used to transmit secret messages and the polarized single photons used for authentication and eavesdropping check. Consequently, because of the dual contributions of the polarized single photons, no classical information is needed. The intrinsic efficiency and total efficiency are both 1 in this scheme as ...

2007-07-01

37

TrustMAS: Trusted Communication Platform for Multi-Agent Systems  

CERN Document Server

The paper presents TrustMAS - Trusted Communication Platform for Multi-Agent Systems, which provides trust and anonymity for mobile agents. The platform includes anonymous technique based on random-walk algorithm for providing general purpose anonymous communication for agents. All agents, which take part in the proposed platform, benefit from trust and anonymity that is provided for their interactions. Moreover, in TrustMAS there are StegAgents (SA) that are able to perform various steganographic communication. To achieve that goal, SAs may use methods in different layers of TCP/IP model or specialized middleware enabling steganography that allows hidden communication through all layers of mentioned model. In TrustMAS steganographic channels are used to exchange routing tables between StegAgents. Thus all StegAgents in TrustMAS with their ability to exchange information by using hidden channels form distributed ...

2008-01-01

38

Exclusive ?0 electroproduction on transversely polarized protons  

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the ...

2009-08-17

39

Adding channels with PSBT format at 40Gbit/s in an existing 10Gbit/s optical network  

British Library Electronic Table of Contents (United Kingdom)

Until recently, the wavelength-division-multiplexed (WDM) transmission system has reached record capacities and distances due to innovations such as FEC (Forward Error Correction), distributed Raman amplification, new transmission fiber and advanced optical format. Optical-communication systems exclusively employed conventional On-Off Keying signals in either Non-Return-To-Zero (NRZ) or Return-To-Zero (RZ) format. Recently a number of advanced modulation formats have attracted attention. Some of these formats carry information through On-Off-Keying but also modulate the optical phase in order to enhance the robustness of signal to chromatic dispersion, optical filtering and non-linearities. Through extensive sets of simulation results, we showed that it is possible to replace a channel wit...

2011-01-01

42

New Lectures on Supergravity  

CERN Document Server

This essay aims to summarize the main physical features arising from a new supersymmetric theory of gravitation. Based on preliminary discussions about classical field theory, cosmology, algebra and group theory, and taking formal results and theoretical considerations in comparison with several contributions from great authors, present work deals with gravity inside the limits of a meta-field theory, that is, a non-quantized but consistent representation of supergravity, the supersymmetry between gravitons and gravitinos. The introduction of meta-fields furnishes an independent framework for the study of gravity despite of constraints of quantization, treating the supersymmetric partners as deterministic actors of gravitation and not simply probabilistic entities. I explain my belief that gravitational field, by its own nature, is not quantizable in the same foot as the other fields, what does not means that we can not ...

2011-01-01

43

A unified framework for biological evolution and stochastic quantization  

CERN Document Server

We investigate the profound relation between the equations of biological evolution and quantum mechanics by writing a biologically inspired equation for the stochastic dynamics of an ensemble of particles. Interesting behavior is observed which is related to a new type of stochastic quantization. We find that the probability distribution of the ensemble of particles can be decomposed into eigenfunctions associated to a discrete spectrum of eigenvalues. In absence of interactions between the particles, the out-of-equilibrium dynamics asymptotically relaxes towards the fundamental state. This phenomenon can be related with the Fisher theorem in biology. On the contrary, in presence of scattering processes the evolution reaches a steady state in which the distribution of the ensemble of particles is characterized by a Bose-Einstein statistics. In order to show a concrete example of this stochastic quantization we have solved explicitly the case in ...

2010-01-01

44

Bounds on the Achievable Rate for the Fading Relay Channel with Finite Input Constellations  

CERN Document Server

We consider the wireless Rayleigh fading relay channel with finite complex input constellations. Assuming global knowledge of the channel state information and perfect synchronization, upper and lower bounds on the achievable rate, for the full-duplex relay, as well as the more practical half-duplex relay (in which the relay cannot transmit and receive simultaneously), are studied. Assuming the power constraint at the source node and the relay node to be equal, the gain in rate offered by the use of relay over the direct transmission (without the relay) is investigated. It is shown that for the case of finite complex input constellations, the relay gain attains the maximum at a particular SNR and at higher SNRs the relay gain tends to become zero. Since practical schemes always use finite complex input constellation, the above result means that the relay offers maximum advantage over the direct transmission when we operate ...

2011-01-01

45

Virasoro algebra action on integrable hierarchies and Virasoro contraints in matrix models  

International Nuclear Information System (INIS)

The action of the Virasoro algebra on integrable hierarchies of non-linear equations and on related objects ('Schroedinger' differential operators) is investigated. The method consists in pushing forward the Virasoro action to the wave function of a hierarchy, and then reconstructing its action on the dressing and Lax operators. This formulation allows one to observe a number of suggestive similarities between the structures involved in the description of the Virasoro algebra on the hierarchies and the structure of conformal field theory on the world-sheet. This includes, in particular, an 'off-shell' hierarchy version of operator products and of the Cauchy kernel. In relation to matrix models, which have been observed to be effectively described by integrable hierarchies subjected to Virasoro constraints, I propose to define general Virasoro-constrained hierarchies also in terms of dressing operators, by certain equations which carry the information of the ...

1991-12-01

46

The phase space of tachyons  

International Nuclear Information System (INIS)

The phase space of quantized systems that contain tachyons has been investigated. Interpretation difficulties and unexpected divergences are found when it is considered the volume of Lorentz-invariant phase space. These problems can be overcome, however, at the expense of Lorentz invariance.

47

Phase space of tachyons  

Energy Technology Data Exchange (ETDEWEB)

The phase space of quantized systems that contain tachyons has been investigated. Interpretation difficulties and unexpected divergences are found when we consider the volume of Lorentz-invariant phase space. These problems can be overcome, however, at the expense of Lorentz invariance.

1983-12-21

48

Numerical simulations of quantized Bianchi type IX cosmological models  

International Nuclear Information System (INIS)

This paper reports on Monte Carlo path integral simulations of a Bianchi Type IX cosmology which yield a wave function which reflects the known chaotic dynamics of the classical system and predicts a significant probability for a correlation between large universe volume and large anisotropy.

1988-08-08

49

Lattice W_N algebra and its quantization  

International Nuclear Information System (INIS)

We consider the integrable structure of the quantum lattice W_N algebras. We introduce the ultralocal Lax matrix, and show that the Yang-Baxter relation is satisfied with a Z_N invariant R-matrix. (orig.).

1997-11-01

50

Extended covariance under nonlinear canonical transformation in Weyl quantization  

CERN Document Server

A theory of nonunitary-invertible as well as unitary canonical transformations is formulated in the context of Weyl's phase space representations. Exact solutions of the transformation kernels and the phase space propagators are given for the three fundamental canonical maps as fractional-linear, gauge and contact (point) transformations. Under the nonlinear maps a phase space representation is mapped to another phase space representation thereby extending the standard concept of covariance. This extended covariance allows Dirac-Jordan transformation theory to naturally emerge from the Hilbert space representations in the Weyl quantization.

2000-01-01

51

Field investigation of radio network usage at the dismounted infantry section level  

Science.gov (United States)

The Soldier Information Requirements Technology Demonstration (SIREQ TD) project is an experimentation program to identify technologies that significantly enhance the performance of our future soldiers. One of the study series involved a 2 x 2 factorial comparison of the benefits of digital maps over paper maps, and the use of radios vs. no radios. Thirty-two Canadian regular force infantry soldiers performed force-on-force tactical assault missions in wooded terrain, with each soldier participating in all four test conditions. The radios were configured to operate in 4 subnets: 1 channel for each of the 2 Assault Groups (4 soldiers on a channel); a Section Commander/2IC channel; and an all-users channel. Note that in the no-radio conditions soldiers still operated the press-to-talk switch to allow recording of communications, but the speaker volume was set to zero. All ...

2006-06-01

52

Solid state and materials research  

International Nuclear Information System (INIS)

Within about 10 years, microelectronic devices will be made with more than a billion (10"9) electronic components per chip. To implement such a sophisticated technology it will be essential to have a fundamental understanding of the solid state interaction between the different materials in thin film semiconductor structures. This is the main purpose of this research program. Characterization and analysis is carried out mainly by Rutherford backscattering spectrometry and channelling using accelerated nuclear particles from the Van de Graaff accelerator, while radioactive isotopes provide information about interaction mechanisms. 6 figs., 1 ref.

53

Input modelling for subchannel analysis of CANFLEX fuel bundle  

Energy Technology Data Exchange (ETDEWEB)

This report describs the input modelling for subchannel analysis of CANFLEX fuel bundle using CASS(Candu thermalhydraulic Analysis by Subchannel approacheS) code which has been developed for subchannel analysis of CANDU fuel channel. CASS code can give the different calculation results according to users' input modelling. Hence, the objective of this report provide the background information of input modelling, the accuracy of input data and gives the confidence of calculation results. (author). 11 refs., 3 figs., 4 tabs.

1998-06-01

54

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

55

Quantum Teleportation with Continuous Variables: a survey  

CERN Document Server

Very recently we have assisted to a new development of quantum information, the so-called continuous variable (CV) quantum information theory. Such a further development has been mainly due to the experimental and theoretical advantages offered by CV systems, i.e., quantum systems described by a set of observables, like position and momentum, which have a continuous spectrum of eigenvalues. According to this novel trend, quantum information protocols like quantum teleportation have been suitably extended to the CV framework. Here, we briefly review some mathematical tools relative to CV systems and we consequently develop the concepts of quantum entanglement and teleportation in the CV framework, by analogy with the qubit-based approach. Some connections between teleportation fidelity and entanglement properties of the underlying quantum channel are inspected. Next, we face the study of CV quantum ...

2006-01-01

56

Scaling Laws and Design Principles for Multi-Cellular Wireless OFDMA Systems  

CERN Document Server

In this paper, we consider the downlink of large-scale multi-cellular OFDMA-based networks and study performance bounds of the system as a function of the number of users $K$, the number of base-stations $B$, and the number of resource-blocks $N$. Here, a resource block is a collection of subcarriers such that all such collections, that are disjoint have associated independently fading channels. We derive novel upper and lower bounds on the sum-utility for a general spatial geometry of base stations, a truncated path loss model, and a variety of fading models (Rayleigh, Nakagami-$m$, Weibull, and LogNormal). We also establish the associated scaling laws and show that, in the special case of fixed number of resource blocks, a grid-based network of base stations, and Rayleigh-fading channels, the sum information capacity of the system scales as $\\Theta(B \\log\\log K/B)$ for extended networks, and as $O(B \\log\\log K)$ and ...

2011-01-01

57

Joint Uplink and Downlink Relay Selection in Cooperative Cellular Networks  

CERN Document Server

We consider relay selection technique in a cooperative cellular network where user terminals act as mobile relays to help the communications between base station (BS) and mobile station (MS). A novel relay selection scheme, called Joint Uplink and Downlink Relay Selection (JUDRS), is proposed in this paper. Specifically, we generalize JUDRS in two key aspects: (i) relay is selected jointly for uplink and downlink, so that the relay selection overhead can be reduced, and (ii) we consider to minimize the weighted total energy consumption of MS, relay and BS by taking into account channel quality and traffic load condition of uplink and downlink. Information theoretic analysis of the diversity-multiplexing tradeoff demonstrates that the proposed scheme achieves full spatial diversity in the quantity of cooperating terminals in this network. And numerical results are provided to further confirm a significant energy efficiency gain of the proposed ...

2010-01-01

58

Design of the electromagnetic fluctuations diagnostic for MFTF-B  

Energy Technology Data Exchange (ETDEWEB)

The Electromagnetic Fluctuations (EMF) diagnostic will be used to monitor ion fluctuations which could be unstable in MFTF-B. Each probe assembly includes a high impedance electrostatic probe to measure potential fluctuations, and a group of nested, single turn loops to measure magnetic fluctuations in three directions. Eventually, more probes and loops will be added to each probe assembly for making more detailed measurements. The sensors must lie physically close to the plasma edge and are radially positionable. Also, probes at separate axial locations can be positioned to connect along the same magnetic field line. These probes are similar in concept to the rf probes used on TMX, but the high thermal load for 30-second shots on MFTF-B requires a water-cooled design along with temperature monitors. Each signal channel has a bandwidth of .001 to 150 MHz and is monitored by up to four different data channels which obtain amplitude and frequency ...

1983-11-28

59

Application of quantitative sedimentology in the characterization of subsurface reservoirs and outcrop analogs  

Energy Technology Data Exchange (ETDEWEB)

The thesis deals with methods of describing the reservoir rock in central oil and gas fields on the Norwegian continental shelf. Methods of enhancing the level of recovery are dealt with. Following topics are given: Sand body dimensions and infill sequences of stable, humid-climate delta plain channels; minipermeameter-based study of permeability trends in channel sand bodies; significance of tidal cyclicity for modelling of reservoir heterogeneities in the lower Jurassic Tilje Formation, mid-Norwegian shelf; geometry and facies of large-scale flow units in fluvial-dominated fan-delta-front sequences; quantified fluvial architecture in ephemeral stream deposits of the Esplugafreda Formation (Palaeocene), Tremp-Graus Basin, northern Spain; the Safari project - collection and storage of field analogue data for quantitative reservoir modelling; sedimentary architecture of field analogues for reservoir information (SAFARI): a ...

1994-12-31

60

A Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties  

Science.gov (United States)

We propose a simultaneous quantum secure direct communication scheme between one party and other three parties via four-particle GHZ states and swapping quantum entanglement. In the scheme, three spatially separated senders, Alice, Bob and Charlie, transmit their secret messages to a remote receiver Diana by performing a series of local operations on their respective particles according to the quadripartite stipulation. From Alice, Bob, Charlie and Diana's Bell measurement results, Diana can infer the secret messages. If a perfect quantum channel is used, the secret messages are faithfully transmitted from Alice, Bob and Charlie to Diana via initially shared pairs of four-particle GHZ states without revealing any information to a potential eavesdropper. As there is no transmission of the qubits carrying the secret message in the public channel, it is completely secure for the direct secret communication. This scheme can be ...

2005-10-01

66

Quantization of the Lie algebra so(2n+1) and of the Lie superalgebra osp(1/2n) with preoscillator generators  

CERN Document Server

The Lie algebra so(2n+1) and the Lie superalgebra osp(1/2n) are quantized in terms of 3n generators, called preoscillator generators. Apart from n "Cartan" elements the preoscillator generators are deformed para-Fermi operators in the case of so(2n+1) and deformed para-Bose operators in the case of osp(1/2n). The corresponding deformed universal enveloping algebras U_q[so(2n+1)] and U_q[osp(1/2n)] are the same as those defined in terms of Chevalley operators. The name "preoscillator" is to indicate that in a certain representation these operators reduce to the known deformed Fermi and Bose operators.

1994-01-01

67

Quantization of coupled 1D vector modes in integrated photonic waveguides  

International Nuclear Information System (INIS)

A quantum mechanical analysis of the guided light in integrated photonics waveguides is presented. The analysis is made starting from one-dimensional (1D) guided vector modes by taking into account the modal orthonormalization property on a cross section of an optical waveguide, the vector structure of the guided optical modes and the reversal-time symmetry in order to quantize the 1D vector modes and to derive the quantum momentum operator and the Heisenberg equations. The results provide a quantum-consistent formulation of the linear and nonlinear quantum light propagations as a function of forward and backward creation and annihilation operators in integrated photonics. As an illustration, an application to an integrated nonlinear directional coupler is given, that is, both the nonlinear momentum and the Heisenberg equations of the nonlinear coupler are derived.

2008-06-01

68

Numerical simulation of conformational variability in biopolymer translocation through wide nanopores  

CERN Document Server

Numerical results on the translocation of long biopolymers through mid-sized and wide pores are presented. The simulations are based on a novel methodology which couples molecular motion to a mesoscopic fluid solvent. Thousands of events of long polymers (up to 8000 monomers) are monitored as they pass through nanopores. Comparison between the different pore sizes shows that wide pores can host a larger number of multiple biopolymer segments, as compared to smaller pores. The simulations provide clear evidence of folding quantization in the translocation process as the biopolymers undertake multi-folded configurations, characterized by a well-defined integer number of folds. Accordingly, the translocation time is no longer represented by a single-exponent power law dependence on the length, as it is the case for single-file translocation through narrow pores. The folding quantization increases with the biopolymer length, while the rate of ...

2009-01-01

69

Improved batch fuzzy learning vector quantization for image compression  

British Library Electronic Table of Contents (United Kingdom)

In this paper, we develop a batch fuzzy learning vector quantization algorithm that attempts to solve certain problems related to the implementation of fuzzy clustering in image compression. The algorithm's structure encompasses two basic components. First, a modified objective function of the fuzzy c-means method is reformulated and then is minimized by means of an iterative gradient-descent procedure. Second, the overall training procedure is equipped with a systematic strategy for the transition from fuzzy mode, where each training vector is assigned to more than one codebook vectors, to crisp mode, where each training vector is assigned to only one codebook vector. The algorithm is fast and easy to implement. Finally, the simulation results show that the method is efficient and appears...

2008-01-01

70

Study on the low-lying collective states of A=54-124 nuclei in 50 MeV #alpha#-particle scattering and in the "6"4Ni("3He, "3He') reaction by DWBA and coupled channel method  

International Nuclear Information System (INIS)

The analysis of elastic and inelastic scattering of #alpha# particles with energy of 50 MeV by nuclei with mass numbers A=54-124 and of "3He particles by the nucleus "6"4Ni is given in the framework of the optical model. The parameters of multipole deformations for lower states are determined. The parameters for quadrupole and octupole deformations of the potential for the nucleus "1"1"2Sn are extracted, the values of the hexadecupole deformation #beta#_4 of the potential for nuclei "9"4Zr, "1"2"0","1"2"4Sn are found. Information is extracted on the ratio of deformation parameters for the neutron and proton components in lower collective states (2_1"+, 3_1"-) of nuclei with A=90-124.

71

Photo-emission-electron-microscopy for characterization of an operating organic electronic device  

Energy Technology Data Exchange (ETDEWEB)

Photoemission-electron-microscopy (PEEM) is introduced as a tool for the characterization of organic electronic devices. PEEM-measurements are used for imaging as well as for spectroscopic analyses by illumination with light of a Hg-lamp (4.9 eV), a D2 lamp (7.3 eV), and with synchrotron radiation for resonant photoelectron spectroscopy. We determine the charge carrier concentration inside the channel region of the organic device and its lateral distribution. From resonant photoelectron spectroscopy (RPES) we deduce the electronic states which are accessible with the Hg and D2 illumination. Photoelectron-spectroscopy at selected areas ({mu}-PES) gives information on the absolute values of surface potentials in lateral resolution. We are able to perform these studies with applied voltages at the source- and drain-electrode.

2006-01-20

72

Learning and case-based reasoning for faults diagnosis-aiding in nuclear power plants  

International Nuclear Information System (INIS)

The aim of this thesis is the design of a faults diagnosis-aiding system in a nuclear facility of the Cea. Actually the existing system allows the optimization of the production processes in regular operating conditions. Meanwhile during accidental events, the alarms, managed by threshold, are bringing no relevant information. To increase the reliability and the safety, the human operator needs a faults diagnosis-aiding system. The developed system, SECAPI, combines problem solving techniques and automatic learning techniques, that allow the diagnosis and the the simulation of various faults happening on nuclear facilities. Its reasoning principle uses case-based and rules-based techniques. SECAPI owns a learning module which reads out knowledge connected with faults. It can then simulate various faults, using the inductive logical computing. SECAPI has been applied on a radioactive tritium treatment operating channel, at the Cea with good ...

1998-01-01

73

Electrical drilling string separator  

Energy Technology Data Exchange (ETDEWEB)

The separator can be used for electrical separation of the drilling string used as the channel of communication with transmission of face information. It contains upper and lower metal conductors electrically insulated from each other by an insulator made of layered polymer composite material. In order to improve reliability of the connection of the conductors to the insulator and reduce the metal consumption on the ends of the conductors that come into contact with the insulator there are graduated niches with radial projections. The latter form jointly with the layers of the insulator a crown-radial-multiple stage undetachable connection. The niches decreases from the outer diameter of the conductors to the inner. The insulator has additional layers made of high-module fibers of carbon or boron which cover the radial projections in stages.

1983-01-01

74

Bongs - a new fertilizer plant  

Energy Technology Data Exchange (ETDEWEB)

In an attempt to overcome inadequacies perceived in the approach to providing energy to village communities using the conventional Khadi and Village Industries Commission biogas plant as well as the Janata model, a biogas digester has been developed suitable for a farmer having only one hectare of land. The information on gas yields and other data from a variety of substrates in a laboratory digester are presented. The digester itself consists of a chamber underground into which the influent flows through a channel. Gas is collected in a dome which constitutes the upper part of the digestion chamber and is maintained under pressure by water. The dome can be made of any suitable material such as plastic, ferrocement and brick and mortar. The upper part of the chamber itself is exposed to sun light which enhances microbial growth. Water which surrounds the dome ensures a minimum of temperature variation. 3 references.

1981-01-01

75

Advanced distillation curve measurements for corrosive fluids: Application to two crude oils  

British Library Electronic Table of Contents (United Kingdom)

We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of...

2008-01-01

76

High resolution scanning electron microscopy of plasmodesmata.  

Science.gov (United States)

Symplastic transport occurs between neighbouring plant cells through functionally and structurally dynamic channels called plasmodesmata (PD). Relatively little is known about the composition of PD or the mechanisms that facilitate molecular transport into neighbouring cells. While transmission electron microscopy (TEM) provides 2-dimensional information about the structural components of PD, 3-dimensional information is difficult to extract from ultrathin sections. This study has exploited high-resolution scanning electron microscopy (HRSEM) to reveal the 3-dimensional morphology of PD in the cell walls of algae, ferns and higher plants. Varied patterns of PD were observed in the walls, ranging from uniformly distributed individual PD to discrete clusters. Occasionally the thick walls of the giant alga Chara were fractured, revealing the surface morphology of PD within. External structures such as spokes, spirals and mesh ...

2011-05-28

77

Quantum tachyons in Schwarzschild space-time  

Energy Technology Data Exchange (ETDEWEB)

The wave equation of a spinless tachyon is studied in Schwarzschild space-time. In contrast to earlier approaches to the problem, it is shown that tachyonic static solutions satisfy a simple second-order linear differential equation regardless of the mass of the black hole and the mass parameter of the tachyon. Physical implication of the present approach is discussed. Using Langer modification of the WKB (Wentzel-Kramers-Brillouin) boundary condition an expression similar to the Bohr-Sommerfeld quantization condition is derived.

1981-02-01

78

On the buildup of laser oscillation from noise  

Science.gov (United States)

It is well known that laser oscillation is initiated by spontaneous radiation ''noise.'' Evidence for this is often based on the complete theory of laser oscillation, including the quantization of the electromagnetic field. In this article, the buildup of laser oscillation from quantum noise is demonstrated using the most elementary classical equation describing the amplification of laser intensity.

1989-02-01

79

Canonical Gravity with Fermions  

CERN Document Server

Canonical gravity in real Ashtekar-Barbero variables is generalized to allow for fermionic matter. The resulting torsion changes several expressions in Holst's original vacuum analysis, which are explicitly displayed here. This in turn requires adaptations to the known canonical (loop) quantization of gravity coupled to fermions, which is discussed on the basis of the classical analysis.

2007-01-01

80

Advanced distillation curve measurements for corrosive fluids: Application to two crude oils  

Energy Technology Data Exchange (ETDEWEB)

We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of crude oil. A primary motivation behind the work is to precisely measure the distillation curves of these oils using our advanced distillation apparatus; ...

2008-10-15

81

Selection of Inhibitor-Resistant Viral Potassium Channels Identifies a Selectivity Filter Site that Affects Barium and Amantadine Block  

UK PubMed Central (United Kingdom)

BackgroundUnderstanding the interactions between ion channels and blockers remains an important goal that has implications for delineating the basic mechanisms of ion channel function...Full Text Available

82

Pore region of TRPV3 ion channel is specifically required for heat-activation  

UK PubMed Central (United Kingdom)

Ion-channels can be activated (gated) by a variety of stimuli including chemicals, voltage, mechanical force or temperature. Whereas molecular mechanisms of ion-channel gating by chemicals and...Full Text Available

2008-09-01

83

Cocurrent Steam/Water Flow in a Horizontal Channel.  

Science.gov (United States)

Measurement of local steam condensation rates of cocurrent stratified flow of steam and subcooled water was carried out at atmospheric pressure in a horizontal rectangular channel. The channel was constructed of stainless steel with pyrex glass windows, a...

1981-01-01

84

Acetylcholine receptor kinetics. A description from single-channel currents at snake neuromuscular junctions.  

UK PubMed Central (United Kingdom)

Single-channel currents from acetylcholine receptor channels of garter snake neuromuscular junctions were recorded using the patch-clamp technique. Low concentrations of acetylcholine or carbamylcholine...Full Text Available

1982-09-01

85

Water management studies in PEM fuel cells, part IV: Effects of channel surface wettability, geometry and orientation on the two-phase flow in parallel gas channels  

British Library Electronic Table of Contents (United Kingdom)

In this study, the effects of channel surface wettability, cross-sectional geometry and orientation on the two-phase flow in parallel gas channels of proton exchange membrane fuel cells (PEMFCs) are investigated. Ex situ experiments were conducted in flow channels with three different surface wettability (hydrophilically coated, uncoated, and hydrophobically coated), three cross-sectional geometries (rectangular, sinusoidal and trapezoidal), and two orientations (vertical and horizontal). Flow pattern map, individual channel flow variation due to maldistribution, pressure drop and flow visualization images were used to analyze the two-phase flow characteristics. It is found that hydrophilically coated gas channels are advantageous over uncoated or slightly hydrophobic channels regarding un...

2011-01-01

86

Mitochondrial Potassium ATP Channels and Retinal Ischemic Preconditioning  

UK PubMed Central (United Kingdom)

PURPOSETo examine the mechanisms of ischemic preconditioning (IPC) related to the opening of mitochondrial KATP (mKATP) channels in the retina.Full Text Available

2006-05-01

87

The entrepreneur's guide to managing information technology  

CERN Document Server

The entrepreneur's guide to managing information technology

2008-01-01

89

Handbook on information technology in finance  

CERN Document Server

Handbook on information technology in finance

2008-01-01

90

Renormalizability of the functional Schroedinger picture in Robertson--Walker space-time  

Energy Technology Data Exchange (ETDEWEB)

We study free and self-interacting scalar quantum field theories in a flat Robertson-Walker metric in the functional Schroedinger picture. We discuss Schroedinger picture quantization, relating it to conventional Heisenberg picture quantization. For the interacting theory, we introduce the time-dependent Gaussian approximation to study time evolution of pure and mixed states and we establish renormalizability of the approximation. We also study the question of computing a finite, renormalized energy-momentum tensor for both the free and the interacting theory in the Gaussian appproximation. Using the adiabatic expansion, we show that the entire subtration necessary to make the the energy-momentum tensor finite in the free theory can be written in terms of covariantly conserved tensors. We further show that the same subtraction is sufficient to make the energy-momentum tensor finite in the Gaussian approximation for the interacting theory ...

1989-07-01

91

Fully quantized many-particle theory of a free-electron laser  

Energy Technology Data Exchange (ETDEWEB)

A fully quantized many-particle theory of the standard free-electron laser in the small-signal, cold-beam regime is presented. The approach is based on an evaluation of the time-evolution operator in the interaction picture to first order in the quantum-mechanical recoil. For algebraic convenience we use the moving (Bambini-Renieri) frame, in which resonance occurs for zero electron momentum. Though we neglect space-charge effects, genuine many-particle contributions still show up, because the radiation emitted by one electron can be amplified by another electron. Our main results are gross features of the amplification, such as gain and spread, are virtually without many-particle effects. These effects are mainly important in the case of spontaneous emission. For a sufficiently high current, the buildup of the laser field from vacuum is enhanced by amplified spontaneous emission. Incoherence of the spontaneous radiation from several electrons induces deviations ...

1983-02-01

92

Weyl gauge, Schwinger terms and bosonization in light-front field theory  

Energy Technology Data Exchange (ETDEWEB)

A systematic study of non-perturbative quantum structure of the massive light-front Schwinger model and QED(3+1) in the continuum formulation is outlined. The light-front Hamiltonian and field algebra are derived in the Weyl gauge using the Dirac-Bergmann constrained quantization. Unitary transformation to the light-cone gauge representation is performed and the gauge-invariant fermi field is constructed. The importance of the Schwinger term in the current-current commutation relations for the derivation of the fermionic vacuum structure and bosonization in two dimensions is indicated.

2002-04-01

93

The canonical form of the Rabi hamiltonian  

CERN Document Server

The Rabi Hamiltonian, describing the coupling of a two-level system to a single quantized boson mode, is studied in the Bargmann-Fock representation. The corresponding system of differential equations is transformed into a canonical form in which all regular singularities between zero and infinity have been removed. The canonical or Birkhoff-transformed equations give rise to a two-dimensional eigenvalue problem, involving the energy and a transformational parameter which affects the coupling strength. The known isolated exact solutions of the Rabi Hamiltonian are found to correspond to the uncoupled form of the canonical system.

1996-01-01

94

Tachyons and quantum field theory  

International Nuclear Information System (INIS)

The problems associated with treating tachoyons in quantum field theory are discussed, and the quantization proposed by Arons and Sudarshan is chosen as the most satisfactory of the presently available methods, although it is unable to describe interactions in its present form. In order to help determine whether suitable S-matrices can ever be found, a perturbation-type expansion for the S-matrix is considered. It is shown that if the first order term is any polynomial in the tachyon field and its conjugate, then the reinterpreted, or physical, S-matrix will violate unitarity. An example shows that the inclusion of derivatives of the field is also expected to produce non-unitary physical S-matrices. The indications are that a correct interesting theory of tachyons must be non-local.

95

Synthesis of histidine-stabilized cadmium sulfide quantum dots: Study of their fluorescence behaviour in the presence of adenine and guanine  

British Library Electronic Table of Contents (United Kingdom)

Cadmium sulfide particles have been synthesized in the aqueous medium using the amino acid histidine as a stabilizing agent. These particles demonstrate the phenomenon of size quantization effect. The fluorescence of histidine-stabilized CdS was found to be enhanced and quenched by the addition of DNA bases adenine and guanine, respectively. The fluorescence enhancement of CdS in the presence of adenine has been explained on the basis of interaction between the quantum dot stabilizer and the amino group of adenine. Quenching of CdS fluorescence by guanine occurs due to interaction of the substrate with the quantum dot surface.

2010-01-01

96

Quantum Computing with an Electron Spin Ensemble  

DEFF Research Database (Denmark)

We propose to encode a register of quantum bits in different collective electron spin wave excitations in a solid medium. Coupling to spins is enabled by locating them in the vicinity of a superconducting transmission line cavity, and making use of their strong collective coupling to the quantized radiation field. The transformation between different spin waves is achieved by applying gradient magnetic fields across the sample, while a Cooper pair box, resonant with the cavity field, may be used to carry out one- and two-qubit gate operations.

2009-01-01

97

Performance Comparisons of PSO based Clustering  

CERN Document Server

In this paper we have investigated the performance of PSO Particle Swarm Optimization based clustering on few real world data sets and one artificial data set. The performances are measured by two metric namely quantization error and inter-cluster distance. The K means clustering algorithm is first implemented for all data sets, the results of which form the basis of comparison of PSO based approaches. We have explored different variants of PSO such as gbest, lbest ring, lbest vonneumann and Hybrid PSO for comparison purposes. The results reveal that PSO based clustering algorithms perform better compared to K means in all data sets.

2010-01-01

98

Gravitational waves from the big bang  

Energy Technology Data Exchange (ETDEWEB)

The gravitational radiation produced by the big bang is calculated in order to provide a condition for the unification of the gravitational and electromagnetic forces. By analogy with electromagnetic radiation and under the assumption that gravity is also quantized, it is shown that matter would have decoupled from gravitational radiation at a time of approximately 10 to the -43rd sec and would have dominated it at 10 to the -17th sec. Furthermore, the theory predicts a background gravitational radiation temperature of 0.003 K which peaks at a wavelength of about 1 m, which may be detected by the comparison of the synchronization of clocks at increasing distances.

1980-12-20

99

Geometry of supersymmetric gauge theories  

Energy Technology Data Exchange (ETDEWEB)

This monograph gives a detailed and pedagogical account of the geometry of rigid superspace and supersymmetric Yang-Mills theories. While the core of the text is concerned with the classical theory, the quantization and anomaly problem are briefly discussed following a comprehensive introduction to BRS differential algebras and their field theoretical applications. Among the treated topics are invariant forms and vector fields on superspace, the matrix-representation of the super-Poincare group, invariant connections on reductive homogeneous spaces and the supermetric approach. Various aspects of the subject are discussed for the first time in textbook and are consistently presented in a unified geometric formalism.

1988-01-01

100

Cocycles, the descent equations, and the Virasoro algebra  

International Nuclear Information System (INIS)

A generalization of Faddeev's group cohomology applicable to diffeomorphism groups is presented. This cohomology is used to calculate the two cocycles associated with a projective representation of the diffeomorphism group on the circle. The group version of the n"3 term descends from a three dimensional Chern-Simons action based on the diffeomorphism group. The group version of the n term arises from an ambiguity in the descent equations of adding closed but not exact forms and is trivial only if its appropriately normalized coefficient is quantized to be an integer. Finally, a hamiltonian interpretation of global anomalies is suggested in the language of group cohomology. (orig.).

1990-05-01

101

Sequential stratigraphy and probabilistic modeling of reservoirs from a deep sea fan (Namorado field, Brazil). Integration of geological and geophysical data; Stratigraphie sequentielle et modelisation probabiliste des reservoirs d`un cone sous-marin profond (champ de Namorado, Bresil). Integration des donnees geologiques et geophysiques  

Energy Technology Data Exchange (ETDEWEB)

The main objective of this dissertation is to build a numerical 3D geological model of a turbidite reservoir using well and seismic data. For the, the first step was to elaborate a depositional model using a high-resolution genetic stratigraphy approach. Simultaneously, the stratigraphic inversion over the seismic data resulted in an optimal acoustic impedance model. Both models, were used to build, by geostatistical methods, a 3-D geological model, which represents the spatial distribution of the reservoir facies. The studied case is the late Cretaceous Namorado turbidite system in the Campos basin, which is the reservoir of the Namorado oil field, located 80 km from the Brazilian coast, under a bathymetry between 110 and 250 m. The reservoir is a turbidite succession with 90 to 180 m thickness. It is composed by sand-supported conglomerates, matrix-supported conglomerate, massive sandstones, shales, marls and limestones. Four lithotypes characterise the main deposits of the turbidite ...

1997-01-29

102

Failure modes of safety-related components at fires on nuclear power plants; Saekerhetsrelaterade systemkomponenters felmoder vid brand paa kaernkraftverk  

Energy Technology Data Exchange (ETDEWEB)

Probabilistic assessment methods can be used to identify specific plant vulnerabilities. Application of such methods can also facilitate selection among system design alternatives available for safety enhancements. The quality of assessment results is however strongly dependent on realistic and accurate input data for modelling of system component behaviour and failure modes during conditions to be assessed. Use of conservative input data may not lead to results providing guidance on safety upgrades. Adequate input data for probabilistic assessments seems to be lacking for at least failure modes of some electrical components when exposed to a fire. This report presents an attempt to improve the situation with respect to such input data. In order to take advantage of information in existing documentation of fire incident occurrences some of the lessons learned from the fire at Browns Ferry Nuclear Power Plant on March 22, 1975 are discussed in this report. Also a ...

2000-03-01

103

Ecological evaluation of proposed dredged material from Richmond Harbor Deepening Project and the intensive study of the Turning Basin  

Energy Technology Data Exchange (ETDEWEB)

Richmond Harbor is on the eastern shoreline of central San Francisco Bay and its access channels and several of the shipping berths are no longer wide or deep enough to accommodate modem deeper-draft vessels. The Water Resources Development Act of 1986 (PL99-662) authorized the US Army Corps of Engineers (USACE), San Francisco District to deepen and widen the navigation channels in Richmond Harbor. Several options for disposal of the material from this dredging project are under consideration by USACE: disposal within San Francisco Bay, at open-ocean disposal sites, or at uplands disposal sites. Purpose of this study was to conduct comprehensive evaluations, including chemical, biological, and bioaccumulation testing of sediments in selected areas of Richmond Harbor. This information was required by the Environmental Protection Agency (EPA) and USACE. Battelle/Marine Sciences Laboratory collected 20 core samples, both 4-in. ...

1995-06-01

104

Correct diagnosis of vascular encasement and longitudinal extension of hilar cholangiocarcinoma by four-channel multidetector-row computed tomography  

International Nuclear Information System (INIS)

Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm x 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to ...

2009-01-01

105

Advanced distillation curve measurement: Application to a bio-derived crude oil prepared from swine manure  

Energy Technology Data Exchange (ETDEWEB)

We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional petroleum crude oils. Then, the information content of the bio-derived oil distillation was extended further with the composition-explicit data ...

2008-11-15

108
109

Pseudostate description of breakup in the coupled-reaction-channel method: Numerical study of nonorthogonality effects  

Energy Technology Data Exchange (ETDEWEB)

To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

1991-03-01

110

Pseudostate description of breakup in the coupled-reaction-channel method: Numerical study of nonorthogonality effects  

International Nuclear Information System (INIS)

To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

112

Modifications to the rotating crystal spectrometer  

International Nuclear Information System (INIS)

... bf3 counters data multi-channel analyzers multivibrators neutron spectrometers

114

Luescher formula for multi-channel systems  

International Nuclear Information System (INIS)

... Ulf G. Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik,

2010-03-15

123

River ice jams at bridges  

Energy Technology Data Exchange (ETDEWEB)

Ice jamming, known to cause high water levels at even moderate river flows, is described as both the main and least understood source of ice-related bridge damages. This paper describes a joint study by the New Brunswick Department of Transportation, the Department of the Environment, local governments, and the National Water Research Institute, designed to address problems associated with the interaction of ice jams and bridges. The study consists of collecting information at each of four sites in New Brunswick including: historical data on ice jam locations, causes, and water levels; channel bathymetry, width and slope within each study centred at the respective bridge; and documentation of ice conditions throughout the ice season, including measurement of ice cover thickness, observation of breakup mechanisms, times, causes, characteristics and possible impacts of ice jam release. Data analysis will include determination of high stages due ...

2000-12-01

124

Herlyn-Werner-Wunderlich syndrome: uterus didelphys, blind hemivagina and ipsilateral renal agenesis. Sonographic and MR findings in 11 cases  

Energy Technology Data Exchange (ETDEWEB)

Uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis is a rare entity, sometimes referred to as Herlyn-Werner-Wunderlich syndrome (HWW). It usually presents after menarche with progressive pelvic pain, sometimes with regular menses, and a palpable mass due to hemihaematocolpos. The diagnosis is generally made only if the suspicion of this genitourinary syndrome is raised. To highlight the imaging diagnostic clues in this rare condition. We report on 11 adolescents with this condition. Sonography mostly allowed the correct diagnosis by showing uterovaginal duplication, haematocolpos or haematometrocolpos, and the absence of the ipsilateral kidney. MRI provided more detailed information regarding uterine morphology, the continuity with each vaginal channel (obstructed and nonobstructed), and the bloody nature of the contents. Early and accurate diagnosis of this syndrome is important so that adequate and prompt surgical ...

2007-07-15

125

Dilepton and Four-Lepton Signals at the LHC in the Littlest Higgs Model with T-parity Violation  

CERN Document Server

In the presence of the T-parity violating Wess-Zumino-Witten (WZW) anomaly term, the otherwise stable heavy photon A_H in the Littlest Higgs model with T-parity (LHT) decays to either Standard Model (SM) gauge boson pairs, or to SM fermions via loop diagrams. We make a detailed study of the collider signatures where the A_H can be reconstructed from invariant mass peaks in the opposite sign same flavor dilepton or the four-lepton channels. This enables us to obtain information about the fundamental symmetry breaking scale f in the LHT and thereby the low-lying mass spectrum of the theory. In addition, indication of the presence of the WZW term gives us hints of the possible UV completion of the LHT via strong dynamics. The crucial observation is that the sum of all production processes of heavy T-odd quark pairs has a sizeable cross-section at the LHC and these T-odd particles eventually all cascade decay down to the heavy photon A_H. We show ...

2009-01-01

126

Difference Antenna Selection and Power Allocation for Wireless Cognitive Systems  

CERN Document Server

In this paper, we propose an antenna selection method in a wireless cognitive radio (CR) system, namely difference selection, whereby a single transmit antenna is selected at the secondary transmitter out of $M$ possible antennas such that the weighted difference between the channel gains of the data link and the interference link is maximized. We analyze mutual information and outage probability of the secondary transmission in a CR system with difference antenna selection, and propose a method of optimizing these performance metrics of the secondary data link subject to practical constraints on the peak secondary transmit power and the average interference power as seen by the primary receiver. The optimization is performed over two parameters: the peak secondary transmit power and the difference selection weight $\\delta\\in [0, 1]$. We show that, difference selection using the optimized parameters determined by the proposed method can be, ...

2010-01-01

127

A Plan to Diffuse Instructional Materials for Use by Transportation Educators.  

Science.gov (United States)

A plan to diffuse instructional modules for the preparation of transportation professionals is presented, based on research and demonstration projects sponsored by the Urban Mass Transportation Administration (UMTA). The diffusion/adoption plan involves: developing instructional modules; disseminating the modules to professors teaching transportation courses at the college level; promoting the use and adoption of the modules; and evaluating and revising the plan. Transportation educators teach in a variety of disciplines (e.g., engineering, public administration, urban planning, and technology). Eight design and evaluation criteria for the instructional modules are listed, along with the procedures used by West Virginia University in developing the five instructional modules. The diffusion strategy involves repackaging UMTA research findings, change agents, and the use of information channels (e.g, television/radio, periodicals, direct mail). ...

1986-01-01

128

Contrasting Diffusion Patterns for PC and Mobile Videos: A User-Centric View of the Influencing Factors  

Science.gov (United States)

As both computer and mobile phone reach nearly ubiquity in the U.S. market, the slow uptake of mobile video, in contrast to the thriving usage of PC-based video, warrants a deeper understanding of user-oriented factors contributing to the two diffusion paths. Unlike the majority of existing diffusion research practices, the dissertation examines the differences between mobile and PC video diffusion patterns through the lenses of user-oriented influences in the user-technology relationship. Built upon the established adoption user group classification, the research is informed by the Uses and Gratification theory, the Social Technical theory, and the Technical Affordance perspective. These synergistic theoretical arguments share the recognition of the role of user in the dynamic, usually socially intertwined user-technology interactions. The key research questions that the dissertation sets out to answer include: Does the importance of quality of viewing ...

2009-12-01

129

Effect on heat-transfer augmentation by channel width in a sinusoidal wave channel  

Energy Technology Data Exchange (ETDEWEB)

In the development of high performance heat transfer surface on a compact heat exchanger, it was clarified that how reattachment point heat transfer and fluid flow are affected by channel width, at the same time, an evaluation of heat transfer performance and an investigation of optimum channel width were carried out. The channel system used in the experiment is as follows; (1) blow-off type with rectangular section channel, (2) span length of 200 mm, (3) wave length (pitch) of 80 mm, and (4) channel length of 12.5 wave length. The channel Reynolds number was set at about 10/sup 4/ which is relatively higher than the current studies. The results of the experiment were summarized as follows. (1) The channel width H has relevance to the phase difference between the fluid flow in cone portion of main stream and wave shape, the flow patterns are ...

1988-06-25

130

Numerical simulation of shallow-water dam break flows in open channels using smoothed particle hydrodynamics  

British Library Electronic Table of Contents (United Kingdom)

SummaryA meshless numerical model is proposed to investigate shallow-water dam break flows in 1D open channels. The numerical model is to solve the shallow water equations (SWE) based on smoothed particle hydrodynamics (SPH). The concept of slice water particles (SWP) is adopted in the SPH-SWE formulation. The numerical sensitivity analysis is first performed to study the appropriate SWP number and variable smoothing length through dam break flows in an idealized 1D channel with dry/wet beds. Extensive validation by comparison with laboratory and field data is next conducted for four benchmark problems, including dam break flows through a rough flat channel, a rough bumpy channel with various downstream boundary conditions, a nonprismatic channel, and a realistic scale model of the Toce ri...

2011-01-01

131

Local heat transfer augmentation in channels with two opposite ribbed surfaces  

Science.gov (United States)

The local heat transfer coefficient distribution of a square channel with two opposite ribbed walls was determined. The square channel was connected to a sudden contraction entrance in order to simulate the inlet condition of the turbine blade cooling passages. The test channel was heated by thin stainless steel foils with a thickness of 0.000025 m, and instrumented with 180 thermocouples. The brass ribs of a square cross-section were glued periodically, in line, onto the top and bottom walls of the foil-heated channel in patterns to achieve the desired spacing and angle-of-attack. The local heat transfer coefficients on the smooth side and the ribbed side walls, at the channel entrance and the downstream regions, were measured for eight rib configurations and three Reynolds numbers (Re = 10,000, 30,000, and 60,000).

1986-01-01

132

Axial and radial distribution of neutron fluxes in the irradiation channels of the Ghana Research Reactor-1 using foil activation analysis and Monte Carlo  

International Nuclear Information System (INIS)

The Monte-Carlo method and experimental methods were used to determine the neutron fluxes in the irradiation channels of the Ghana Research Reactor -1. The MCNP5 code was used for this purpose to simulate the radial and axial distribution of the neutron fluxes within all the ten irradiation channels. The results obtained were compared with the experimental results. After the MCNP simulation and experimental procedure, it was observed that axially, the fluxes rise to a peak before falling and then finally leveling out. Axially and radially, it was also observed that the fluxes in the centre of the channels were lower than on the sides. Radially, the fluxes dip in the centre while it increases steadily towards the sides of the channels. The results have shown that there are flux variations within the irradiation channels both axially and radially. (au)

2009-01-01

133

45 CFR 170.210 - Standards for health information technology to protect electronic health information created...  

Science.gov (United States)

...2010-10-01 false Standards for health information technology to protect electronic health information...DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION...

2010-10-01

134

The Value of Information The Metaphysics of Information The - NASA  

Science.gov (United States)

Wikileaks was inevitable. The Dynamics of. Information. Take advantage of the eddy currents. You can't step in the same river ...

135

NASA Information Technology Requirement Main Menu  

Science.gov (United States)

Headquarters Centrally-Funded Information Technology (IT) Resource Allocation .... Information Technology Policy Formulation Process ...

136

Information Technology (IT) Management: The Clinger-Cohen ...  

Science.gov (United States)

... Information Technology (IT) Management: ... The role of information technology figures prominently in the Homeland Security Act of 2002. ...

2005-02-03

137

Information Technology Research (ITR) for National Priorities  

Science.gov (United States)

Information Technology Research for National Priorities (ITR) Fiscal Year 2004 Announcement ... the Information Technology Research (ITR) Program is focusing on Information Technology Research in ...

138

Zebrafish TRPA1 Channels are Required for Chemosensation but not for Thermosensation or Mechanosensory Hair Cell Function  

UK PubMed Central (United Kingdom)

Transient receptor potential (TRP) ion channels have been implicated in detecting chemical, thermal and mechanical stimuli in organisms ranging from mammals to Caenorhabditis elegans....Full Text Available

2008-10-01

139

The opening of the two pores of the Hv1 voltage-gated proton channel is tuned by cooperativity  

UK PubMed Central (United Kingdom)

SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available

2010-01-01

140

The Antibacterial Activity of Human Neutrophils and Eosinophils Requires Proton Channels but Not BK Channels  

UK PubMed Central (United Kingdom)

Electrophysiological events are of central importance during the phagocyte respiratory burst, because NADPH oxidase is electrogenic and voltage sensitive. We investigated the recent suggestion that...Full Text Available

2006-06-01

141

Temperature-induced opening of TRPV1 ion channel is stabilized by the pore domain  

UK PubMed Central (United Kingdom)

SummaryTRPV1 is the founding and best-studied member of the family of temperature-activated transient receptor potential ion channels (thermoTRPs). Voltage, chemicals, and heat...Full Text Available

2010-06-01

142

SUN WORSHIPER: McCready's Solar Challenger flies over the English Channel  

Energy Technology Data Exchange (ETDEWEB)

The background for the project of a solar-powered aircraft, designed and built by Dr. Paul McCready of California, is reported with details on the aircraft design and its flight across the English Channel.

1983-12-01

143

Regulation of ROMK1 Channels by Protein-tyrosine Kinase and -tyrosine Phosphatase*  

UK PubMed Central (United Kingdom)

We have used the two-electrode voltage clamp technique and the patch clamp technique to investigate the regulation of ROMK1 channels by protein-tyrosine phosphatase (PTP) and protein-tyrosine...Full Text Available

2001-03-09

144

Parallel helix bundles and ion channels: molecular modeling via simulated annealing and restrained molecular dynamics.  

UK PubMed Central (United Kingdom)

A parallel bundle of transmembrane (TM) alpha-helices surrounding a central pore is present in several classes of ion channel, including the nicotinic acetylcholine receptor (nAChR). We have modeled...Full Text Available

1994-10-01

145

Increased rigidity of the chiral centre of tocainide favours stereoselectivity and use-dependent block of skeletal muscle Na+ channels enhancing the antimyotonic activity in vivo  

UK PubMed Central (United Kingdom)

Searching for the structural requirements improving the potency and the stereoselectivity of Na+ channel blockers as antimyotonic agents, new...Full Text Available

2001-12-01

146

Forward Trafficking of Ion Channels: What the Clinician Needs to Know  

UK PubMed Central (United Kingdom)

Each heartbeat requires precisely orchestrated action potential propagation through the myocardium achieved by coordination of about a million ion channels on the surface of each cardiomyocyte....Full Text Available

2010-08-01

147

Entropic effects in channel-facilitated transport: Inter-particle interactions break the flux symmetry  

UK PubMed Central (United Kingdom)

We analyze transport through conical channels due to the difference in particle concentration on the two sides of the membrane. Because of the detailed balance, fluxes of non-interacting particles...Full Text Available

2009-08-01

148

Dual-channel imaging system for singlet oxygen and photosensitizer for PDT  

UK PubMed Central (United Kingdom)

A two-channel optical system has been developed to provide spatially resolved simultaneous imaging of singlet molecular oxygen (1O2) phosphorescence and photosensitizer (PS) fluorescence...Full Text Available

149

Dimeric subunit stoichiometry of the human voltage-dependent proton channel Hv1  

UK PubMed Central (United Kingdom)

In voltage-gated Na+, K+, and Ca2+ channels, four voltage-sensor domains operate on a central pore domain in response to membrane voltage. In contrast, the voltage-gated...Full Text Available

2008-06-03

150

Detrusor overactivity is associated with downregulation of large-conductance calcium- and voltage-activated potassium channel protein  

UK PubMed Central (United Kingdom)

Large-conductance voltage- and calcium-activated potassium (BK) channels have been shown to play a role in detrusor overactivity (DO). The goal of this study was to determine whether bladder outlet...Full Text Available

2010-06-01

151

Chaotic system of two-phase flow in a small, horizontal, rectangular channel.  

Science.gov (United States)

Various measurement tools that are used in chaos theory were applied to analyze two-phase pressure signals with the objective of identifying and interpreting flow pattern transitions for two-phase flows in a small, horizontal rectangular channel. These me...

1995-01-01

152

Augmented behavioral response and enhanced synaptosomal calcium transport induced by repeated cocaine administration are decreased by calcium channel blockers  

UK PubMed Central (United Kingdom)

Recent studies suggest that calcium influx via L-type calcium channels is necessary for psychostimulant-induced behavioral sensitization. In addition, chronic amphetamine upregulates subtype...Full Text Available

2007-07-26

153

A novel Na+ channel splice form contributes to the regulation of an androgen-dependent social signal  

UK PubMed Central (United Kingdom)

Na+ channels are often spliced but little is known about the functional consequences of splicing. We have been studying the regulation of Na+ current inactivation in an...Full Text Available

2008-09-10

154

17?-estradiol regulation of T-type calcium channels in gonadotropin-releasing hormone neurons  

UK PubMed Central (United Kingdom)

T-type calcium channels are responsible for generating low-threshold spikes that facilitate burst firing and neurotransmitter release in neurons. GnRH neurons exhibit burst firing, but the underlying...Full Text Available

2009-08-26

155

Solution conformations of CaCl sub 2 and Ca(NO sub 3 ) sub 2 complexes of chiral tetramethyl 18-crown-6 macrocycles: A 1D and 2D sup 1 H and sup 13 C NMR investigation  

Energy Technology Data Exchange (ETDEWEB)

One- and two-dimensional NMR techniques have been used to investigate the solution structures of (2S,6S,11S,15S)-2,6,11,15-tetramethyl-1,4,7,10,13,16-hexaoxacyclooctadecane (I) and (2R,3R,11R,12R)-2,3,11,12-tetramethyl-1,4,7,10,13,16-hexaoxyacyclooctadecane (II) macrocycle complexes of CaCl{sub 2} and Ca(NO{sub 3}){sub 2} in CDCl{sub 3}. Previous chiroptical studies of these and similar crown complexes by circularly polarized luminescence (CPL), total luminescence (TL), and circular dichroism (CD) spectroscopy have shown that the macrocycle asymmetric carbons in these complexes constrain the ring such that the sense of the ring twist in the S chiral ring complexes is opposite to that in the R chiral ring complexes. These studies have also shown that there is an added chirality element in the di- and trivalent (alkaline earth and lanthanide metal, respectively) nitrate complexes of I and II associated with the twist of the nitrate anions relative to one another as they sterically ...

1989-10-04

156

Theoretical and Experimental Investigation of Flamespreading ...  

Science.gov (United States)

... CHANNELS, TWO PHASE FLOW, WAVES, IGNITERS, GAS FLOW, HOWITZERS, CARTRIDGE CASES, COMBUSTIBLE CARTRIDGE CASES. ...

1986-02-01

157

Technology Transfer. Volume 2  

Science.gov (United States)

... table (ASCAMP) system and the Military Strategic and Tactical Relay (Milstar) program. 10 ... Single Channel Antijam Milstar Portable Terminal ...

1992-04-01

158

RATIO COMPUTER  

Science.gov (United States)

An electronic computer circuit is described for producing an output voltage proportional to the product or quotient of tbe voltages of a pair of input signals. ln essence, the disclosed invention provides a computer having two channels adapted to receive separate input signals and each having amplifiers with like fixed amplification factors and like negatlve feedback amplifiers. One of the channels receives a constant signal for comparison purposes, whereby a difference signal is produced to control the amplification factors of the variable feedback amplifiers. The output of the other channel is thereby proportional to the product or quotient of input signals depending upon the relation of input to fixed signals in the first mentioned channel.

1958-11-11

159

Multistep contributions in "8"8Sr(h,t)"8"8Y  

International Nuclear Information System (INIS)

... mixing coupled channel theory differential cross sections excited states helium

160

MR-6 Type Fuel Elements Cooling in Natural Convection Conditions after Reactor Shutdown  

International Nuclear Information System (INIS)

... Natural convection cooling of the channel type reactor performed with the fuel

1992-08-03

161

Development and Calibration of Two and Four Wire Water ...  

Science.gov (United States)

... measurement. Power spectral density measurements are made by the dynamic signal analyzer for each channel. A cross power ...

1992-12-01

162

Computing the distance between quantum channels: usefulness of the Fano representation  

Energy Technology Data Exchange (ETDEWEB)

The diamond norm measures the distance between two quantum channels. From an operational viewpoint, this norm measures how well we can distinguish between two channels by applying them to the input states of arbitrarily large dimensions. In this paper, we show that the diamond norm can be conveniently, and in a physically transparent way, computed by means of a Monte Carlo algorithm based on the Fano representation of quantum states and quantum operations. The effectiveness of this algorithm is illustrated for several single-qubit quantum channels.

2010-11-14

163

Selective Expression in Carotid Body Type I Cells of a Single Splice Variant of the Large Conductance Calcium- and Voltage-activated Potassium Channel Confers Regulation by AMP-activated Protein Kinase*  

UK PubMed Central (United Kingdom)

Inhibition of large conductance calcium-activated potassium (BKCa) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BKCa channels remain active...Full Text Available

2011-04-08

164

Multi-channel algebraic scattering theory and the structure of exotic compound nuclei  

CERN Document Server

A Multi-Channel Algebraic Scattering (MCAS) theory is presented with which the properties of a compound nucleus are found from a coupled-channel problem. The method defines both the bound states and resonances of the compound nucleus, even if the compound nucleus is particle unstable. All resonances of the system are found no matter how weak and/or narrow. Spectra of mass-7 nuclei and of {}^{15}F, and MCAS results for a radiative capture cross section are presented.

2007-01-01

165

Mixed convection flows in a channel with a vortex generator  

Science.gov (United States)

This paper presents a numerical investigation of laminar flows and heat transfer in a horizontal rectangular channel whose top and bottom plates have been punched out in the form of a delta wing. The flow structure with respect to the generation, transport, and stability of vortices in laminar horizontal channel flows with combined forced and free convection are reported. To include free convection, Boussinesq approximation of the buoyancy is used and the flow medium is treated as incompressible.

1989-01-01

166

Magnesium Sensitizes Slow Vacuolar Channels to Physiological Cytosolic Calcium and Inhibits Fast Vacuolar Channels in Fava Bean Guard Cell Vacuoles1  

UK PubMed Central (United Kingdom)

Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca2+, calmodulin, protein kinases, and phosphatases....Full Text Available

1999-11-01

167

Kv1.1 potassium channel deficiency reveals brain-driven cardiac dysfunction as a candidate mechanism for sudden unexplained death in epilepsy(SUDEP)  

UK PubMed Central (United Kingdom)

Mice lacking Kv1.1 Shaker-like potassium channels encoded by the Kcna1 gene exhibit severe seizures and die prematurely. The channel is widely expressed in...Full Text Available

2010-04-14

168

A structure modeling of metal-silicide layers by using axial and planar channeling techniques  

International Nuclear Information System (INIS)

Planar channeling effects are studied in such well-oriented polycrystalline layers as NiSi_2 and Pb_2Si layers formed on single crystalline Si. Crystalline perfection of such layers is discussed by using the energy- and angular dependences of the axial and planar channeling yields. It has been shown that, in suitable conditions, the energy dependence of the planar yield is more sensitive to the spread of crystallite orientations in polycrystals than that of the axial one. (Auth.).

169

A new type of scorpion Na+-channel-toxin-like polypeptide active on K+ channels  

UK PubMed Central (United Kingdom)

We have purified and characterized two peptides, named KAaH1 and KAaH2 (AaH polypeptides 1 and 2 active on K+ channels, where AaH stands for Androctonus australis Hector),...Full Text Available

2005-06-01

170

Two-level atom at finite temperature  

CERN Document Server

Properties of a two-level atom coupled to the quantized electromagnetic field at finite temperature are studied. The analysis is based on a new method (inspired by QED) of describing qubits, developed previously by us at zero temperature (Phys. Rev. A 76, 062106 (2007)). In this paper, we make a generalization to finite temperature by introducing the Matsubara formalism and the temperature propagators. We analyze the spectral properties of different types of propagators and we derive a direct connection between the temperature propagators and the real time propagators. To show the effectiveness of this method, we calculate the temperature dependence of the polarizability of a two-level atom in the lowest order of perturbation theory and we predict an unexpected sharpness in the resonance behavior. The whole discussion is carried out without making the rotating wave approximation.

2009-01-01

171

Strong fields and recycled accelerator parts as a laboratory for fundamental physics  

International Nuclear Information System (INIS)

Over the last few years it has become increasingly clear that low energy, but high precision experiments provide a powerful and complementary window to physics beyond the Standard Model. In this note we illuminate this by using minicharged particles as an example. We argue that minicharged particles arise naturally in extensions of the Standard Model. Compatibility with charge quantization arguments suggests that minicharged particles typically arise together with a massless hidden sector U(1) gauge field. We present several low energy experiments employing strong lasers, electric and magnetic fields that can be used to search for (light) minicharged particles and their accompanying U(1) gauge boson.

2009-12-01

172

Renormalization of Lorentz non-invariant actions and manifest T-duality  

CERN Document Server

We study general two-dimensional sigma-models which do not possess manifest Lorentz invariance. We show how demanding that Lorentz invariance is recovered as an emergent on-shell symmetry constrains these sigma-models. The resulting actions have an underlying group-theoretic structure and resemble Poisson--Lie T-duality invariant actions. We consider the one-loop renormalization of these models and show that the quantum Lorentz anomaly is absent. We calculate the running of the couplings in general and show, with certain non-trivial examples, that this agrees with that of the T-dual models obtained classically from the duality invariant action. Hence, in these cases solving constraints before and after quantization are commuting operations.

2009-01-01

173

Phenomenological dynamics of loop quantum cosmology in Kantowski-Sachs spacetime  

CERN Document Server

The full theory and the semiclassical description of loop quantum cosmology (LQC) have been studied in the Friedmann-Robertson-Walker and Bianchi I models. As an extension to include both anisotropy and intrinsic curvature, this paper investigates the cosmological model of Kantowski-Sachs spacetime with a free massless scalar field at the level of phenomenological dynamics with the LQC discreteness corrections. The LQC corrections are implemented in two different improved quantization schemes. In both schemes, the big bang and big crunch singularities of the classical solution are resolved and replaced by the big bounces when the area or volume scale factor approaches the critical values in the Planck regime measured by the reference of the scalar field momentum. Symmetries of scaling are also noted and suggest that the fundamental spatial scale (area gap) may give rise to a temporal scale. The bouncing scenarios are in an analogous fashion of the Bianchi I model, ...

2008-01-01

174

Neutrinos and long-range weak forces in cosmology  

International Nuclear Information System (INIS)

The Lorentz and coordinate covariant calculus of spinors in Riemannian spacetime, which is the mathematical model for the description of the quantum mechanics of elementary particles with spin interacting with the classical gravitation field, is explored. The Dirac equation describing the interaction of neutrinos with the gravitational fields of the Robertson-Walker cosmological world models is separated, and the spectrum of eigenfunctions and eigenvalues for particular choices of the set of quantum numbers is given explicitly for the k = 0 and k = +1 models, although only the radial equations determining the final quantum number are given for the k = -1 model. The mathematical theory of the motion of a perfect fluid whose elements interact via long-range neutrino-exchange forces, as well as gravitationally, is developed. The formalism for calculating, by calculating the Bogoliubov transformation of the Fock space operators that instantaneously diagonalize their ...

175

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

176

Formation of pentagonal Cu nano wires  

Energy Technology Data Exchange (ETDEWEB)

The development of nano/molecular devices will require atomic-sized electrical contacts or nano metric conductors for wiring. As metal nano wires exhibit quantized conductance at room temperature, quantum transport effects will play an important role in the practical implementation of nano devices. As copper is currently used as interconnecting metal in standard microelectronics, the characterization of Cu nano wire properties deserves special attention. In this work, we show a detailed study of structural and electronic properties of atomic-sized Cu wires. In particular, we have established a complete correlation between the conductance and the structure by associating real-time atomic resolution transmission electron microscopy imaging with molecular dynamic simulations, conductance measurements and conductance calculations. Our study has revealed the structural relaxation of Cu wires forming a pentagonal atomic arrangement along the [110] direction that allows a ...

2004-07-01

177

Einstein's fluctuation formula. A historical overview  

CERN Document Server

A historical overview is given on the basic results which appeared by the year 1926 concerning Einstein's fluctuation formula of black-body radiation, in the context of light-quanta and wave-particle duality. On the basis of the original publications (from Planck's derivation of the black-body spectrum and Einstein's introduction of the photons up to the results of Born, Heisenberg and Jordan on the quantization of a continuum) a comparative study is presented on the first line of thoughts that led to the concept of quanta. The nature of the particle-like fluctuations and the wave-like fluctuations are analysed by using several approaches. With the help of the classical probability theory, it is shown that the infinite divisibility of the Bose distribution leads to the new concept of classical poissonian photo-multiplets or to the binary photo-multiplets of fermionic character. As an application, Einstein's fluctuation formula is derived as a sum of fermion type ...

2006-01-01

178

Covariance of quantum general relativity from Ashtekar variables  

CERN Document Server

In this paper we examine the relationship between covariance and unitarity for quantum gravity in Ashtekar variables. A usual description would discard half of the original Lorentz group, in exchange for the resulting simplifications of general relativity. We start by quantizing a trivial SL(2,C) gauge theory resulting in a nonunitary covariant theory. By the addition of a total time derivative we transform this into a unitary theory of the Ashtekar description of gravity with complete accountability of the degrees of freedom. We find that covariance on the spacetime level bears a direct relationship to covariance on the level ofthe quantum fields themselves. This procedure can in principle be applied to any totally constrained system, and bears a resemblance to the Gupta--Bleuler method. Finally, we make some observation regarding the loop representation of the SL(2,C) connection.

2008-01-01

179

Consistency conditions in the chiral ring of super Yang-Mills theories  

CERN Document Server

Starting from the generalized Konishi anomaly equations at the non-perturbative level, we demonstrate that the algebraic consistency of the quantum chiral ring of the N=1 super Yang-Mills theory with gauge group U(N), one adjoint chiral superfield X and N_f<=2N flavours of quarks implies that the periods of the meromorphic one-form Tr dz/(z-X) must be quantized. This shows in particular that identities in the open string description of the theory, that follow from the fact that gauge invariant observables are expressed in terms of gauge variant building blocks, are mapped onto non-trivial dynamical equations in the closed string description.

2007-01-01

180

An effective approach to the problem of time: general features and examples  

CERN Document Server

The effective approach to quantum dynamics allows a reformulation of the Dirac quantization procedure for constrained systems in terms of an infinite-dimensional constrained system of classical type. For semiclassical approximations, the quantum constrained system can be truncated to finite size and solved by the reduced phase space or gauge-fixing methods. In particular, the classical feasibility of local internal times is directly generalized to quantum systems, overcoming the main difficulties associated with the general problem of time in the semiclassical realm. The key features of local internal times and the procedure of patching global solutions using overlapping intervals of local internal times are described and illustrated by two quantum mechanical examples. The choice of time is tantamount to a choice of gauge at the effective level and changing the clock is, therefore, equivalent to a gauge transformation. This article complements the conceptual ...

2010-01-01

181

Algebraic Topology Foundations of Supersymmetry and Symmetry Breaking in Quantum Field Theory and Quantum Gravity: A Review  

CERN Document Server

A novel algebraic topology approach to supersymmetry (SUSY) and symmetry breaking in quantum field and quantum gravity theories is presented with a view to developing a wide range of physical applications. These include: controlled nuclear fusion and other nuclear reaction studies in quantum chromodynamics, nonlinear physics at high energy densities, dynamic Jahn-Teller effects, superfluidity, high temperature superconductors, multiple scattering by molecular systems, molecular or atomic paracrystal structures, nanomaterials, ferromagnetism in glassy materials, spin glasses, quantum phase transitions and supergravity. This approach requires a unified conceptual framework that utilizes extended symmetries and quantum groupoid, algebroid and functorial representations of non-Abelian higher dimensional structures pertinent to quantized spacetime topology and state space geometry of quantum operator algebras. Fourier transforms, generalized Fourier-Stieltjes ...

2009-01-01

182

AlGaInP visible vertical cavity surface emitting lasers operating with gain contributions from the [ital n]=2 quantum well transition  

Science.gov (United States)

We report the characteristics of visible vertical cavity surface emitting laser diodes. Wafers are grown such that the Fabry--Perot resonance wavelength changes with position from 690 to 620 nm, overlapping to varying degrees with the [ital n]=1 and [ital n]=2 quantum well gain peaks at [similar to]670 and 650 nm. Gain guided devices are tested across the entire wafer, and pulsed room temperature lasing is observed from 634.6 to 663.2 nm. Our results suggest that gain contributions from the second quantized state are required to overcome high cavity losses in order to achieve lasing.

1993-12-20

183

A lattice gauge theory model for graphene  

CERN Document Server

In this Ph.D. thesis a model for graphene in presence of quantized electromagnetic interactions is introduced. The zero and low temperature properties of the model are studied using rigorous renormalization group methods and lattice Ward identities. In particular, it is shown that, at all orders in renormalized perturbation theory, the Schwinger functions and the response functions decay with interaction dependent anomalous exponents. Regarding the 2-point Schwinger function, the wave function renormalization diverges in the infrared limit, while the effective Fermi velocity flows to the speed of light. Concerning the response functions, those associated to a Kekul\\'e distortion of the honeycomb lattice and to a charge density wave instability are enhanced by the electromagnetic electron-electron interactions (their scaling in real space is depressed), while the lowest order correction to the scaling exponent of the density-density response function is vanishing. ...

2011-01-01

185

The Bipolar Field-Effect Transistor: VIII. Longitudinal Gradient of Longitudinal Electric Field (Two-MOS-Gates on Pure-Base)  

International Nuclear Information System (INIS)

This paper evaluates the electric current terms from the longitudinal gradient of the longitudinal electric field in Bipolar Field-Effect-Transistors (BiFETs) with a pure base and two MOS gates operating in the unipolar (electron) current mode. These nMOS-BiFETs, known as nMOS-FinFETs, usually have electrically short channels compared with their intrinsic Debye length of about 25 #mu#m at room temperatures. These longitudinal electric current terms are important short-channel current components, which have been neglected in the computation of the long-channel electrical characteristics. This paper shows that the long-channel electrical characteristics are substantially modified by the longitudinal electrical current terms when the physical channel length is less than 100 nm.

2010-07-01

186

Experimental investigation of forced and mixed convection heat transfer in a foam-filled horizontal rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

An experimental study was performed to investigate the heat transfer characteristics of the mixed convection flow through a horizontal rectangular channel where open-cell metal foams of different pore densities (10, 20 and 30 PPI) were situated. A uniform heat flux was applied at all of the bounding walls of the channel. For each of three values of the uniform heat flux, temperatures were measured on the entire surfaces of the walls. Results for the average and local Nusselt numbers are presented as functions of the Reynolds and Richardson numbers. The Reynolds number based on the channel height of the rectangular channel was varied from 600 to 33000, while the Richardson number ranged from 0.02 to 103, extending over forced, mixed and natural convection. Second important parameter that in...

2009-01-01

187

Experimental Investigation and RELAP5 Modeling of Two-Phase Flow in Horizontal Rectangular Channel  

British Library Electronic Table of Contents (United Kingdom)

The investigation of steam, water, and air flow characteristics in horizontal channel is a part of major investigations program at the Lithuanian Energy Institute. The objective of this program is to identify condensation effects on two-phase flow stability and to predict conditions when rapid condensation could be induced in two-phase condensable flow. This article presents investigation of steam-water and air multiphase flow in nearly horizontal rectangular channel. The experimental data for pressure drop and interfacial and wall shear stresses in the channel with uniform distribution of void fraction are presented in this paper. Overall channel dimensions are length = 1.2 m, width = 0.02 m, height = 0.1 m; however, the test section was about 0.84 m in length. Three different flow types ...

2011-01-01

188

Exergy transfer in a porous rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Present paper is performed to investigate the heat and exergy transfer characteristics of forced convection flow through a horizontal rectangular channel where open-cell metal foams of different pore densities such as 10, 20 and 30PPI (per pore inches) were situated. All of the bounding walls of the channel are subjected to various uniform heat fluxes. The pressure drop and heat transfer characteristics are presented by two important parametric values, Nusselt number (NuH) and friction factor (f), as functions of Reynolds number (ReH) and the wall heat flux (q). The Reynolds number (ReH) based on the channel height of the rectangular channel is varied from 600 to 33 000, while the Grashof number (GrDh) ranged from approximately 105-107 depending on q. Based on the experimental data, new em...

2010-01-01

189

Cardiac Channelopathies and Sudden Infant Death Syndrome  

British Library Electronic Table of Contents (United Kingdom)

Abstract Sudden infant death syndrome (SIDS) is always a devastating and unexpected occurrence. SIDS is the leading cause of death in the first 6 months after birth in the industrialized world. Since the discovery in 1998 of long QT syndrome as an underlying substrate for SIDS, around 10-20% of SIDS cases have been proposed as being caused by genetic variants in either ion channel or ion channel-associated proteins. Until now, 10 cardiac channelopathy susceptibility genes have been found to be implicated in the pathogenesis of SIDS. Four of the genes encode cardiac ion channel a-subunits, 3 genes encode ion channel b-subunits, and 3 genes encode other channel-interacting proteins. All 10 genes have been associated with primary electrical heart diseases. SIDS may hereby be the initial sympt...

2011-01-01

190

Blind Adaptive Subcarrier Combining Technique for MC-CDMA Receiver in Mobile Rayleigh Channel  

CERN Document Server

A new subcarrier combining technique is proposed for MC -CDMA receiver in mobile Rayleigh fading channel. It exploits the structure formed by repeating spreading sequences of users on different subcarriers to simultaneously suppress multiple access interference (MAI) and provide implicit channel tracking without any knowledge of the channel amplitudes or training sequences. This is achieved by adaptively weighting each subcarrier in each symbol period by employing a simple gradient descent algorithm to meet the constant modulus (CM) criterion with judicious selection of step-size. Improved BER and user capacity performance are shown with similar complexity in order of O(N) compared with conventional maximum ratio combining and equal gain combining techniques even under high channel Doppler rates.

2011-01-01

191

Information Sharing in the Era of WikiLeaks: Balancing Security and Collaboration.  

Science.gov (United States)

As the IC Information Sharing Executive (IC ISE), my main focus today concerns classified information--and, in particular, information that is derived from intelligence sources and methods, or information that is reflected in the analytic judgments and as...

2011-01-01

192

Two-phase flow regime observations in a vertical hexagonal flow channel with and without a finned fuel bundle  

International Nuclear Information System (INIS)

Previous flow regime studies have been for horizontal, vertical, and inclined pipe flow. As such, only a few studies have been performed on bundle geometries. The present paper examines the flow regimes for a vertical hexagonal flow channel with and without a finned fuel bundle. This type of a 36 finned rod hexagonal fuel bundle in parallel hexagonal flow channels is used in a MAPLE (Multi- purpose Applied Physics Lattice Experimental) type nuclear reactor. An experiment apparatus was designed consisting of the flow channel, inlet plenum and an air-water separator. The inlet plenum is used to provide a uniform mixture of air and water before entering the hexagonal flow channel. A turbine flow meter is used to determine the water flow rate. The turbine flow meter is calibrated for a low flow range and limits the measurable flow to 50 l/min. Flow pattern observation is determined by a SONY video camera, ...

1990-12-10

193

Simulation of velocity profiles in a laboratory electrolyser using computational fluid dynamics  

International Nuclear Information System (INIS)

A commercial CFD code, Fluent, has been used to analyse the design of a filter-press reactor operating with characteristic linear flow velocities between 0.024 and 0.192 m s-1. Electrolyte flow through the reactor channel was numerically calculated using a finite volume approach to solve the Navier-Stokes equations. The length of the channel was divided into 7 sections corresponding to distances of 0, 0.01, 0.04, 0.08, 0.12, 0.14 and 0.15 m from the electrode edge nearest to the inlet. The depth of the channel was divided into three planes parallel to the channel bottom. For each channel section, a velocity profile was obtained at each depth together with the average velocity in each plane. The flow predictions show that the flow development, as the electrolyte passes through the cell, is strongly affected by the manifold causing strong vortex structures at the entrance and exit of ...

2010-04-01

194

Estimation of CHF ratio at various power levels in TAPP-3 and 4 reactors  

International Nuclear Information System (INIS)

TAPP-3 and 4 are the 540 MWe PHWRs having horizontal fuel channel. At normal 100% FP operation there is no boiling in the channel. However, when the power increases due to any transient, the boiling may start in the channel. The main application for critical heat flux (CHP) prediction is to set the operating power with a comfortable margin to avoid CHF occurrence. This margin of CHF can be expressed in terms of minimum critical heat flux ratio (MCHFR), which is the ratio of CHF to local heat flux for the same pressure, mass flux and quality. The CHF depends on power, coolant flow rate as well as coolant condition in the channel. As the power increases the flow reduces in the channel and cooling is degraded. The thermal hydraulic code is developed for present analysis. The output of analysis are CHF prediction quality calculation at axial locations of the maximum rated ...

2005-12-01

195

Determination of two-phase flow parameters for nuclear fuel channels using a real-time neutron radiography method  

Energy Technology Data Exchange (ETDEWEB)

Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10{sup 6}n/cm{sup 2}-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,{integral}dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, ...

1995-07-01

196

Determination of two-phase flow parameters for nuclear fuel channels using a real-time neutron radiography method  

International Nuclear Information System (INIS)

Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10"6n/cm"2-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,#integral#dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and ...

1346-01-01

197

Personal Information Databases  

CERN Document Server

One of the most important aspects of security organization is to establish a framework to identify security significant points where policies and procedures are declared. The (information) security infrastructure comprises entities, processes, and technology. All are participants in handling information, which is the item that needs to be protected. Privacy and security information technology is a critical and unmet need in the management of personal information. This paper proposes concepts and technologies for management of personal information. Two different types of information can be distinguished: personal information and nonpersonal information. Personal information can be either personal identifiable information (PII), or nonidentifiable information ...

2009-01-01

198

TRANSPORT CHARACTERISTICS OF REPRESENTATIVE DEBRIS IN A OPEN CHANNEL  

Energy Technology Data Exchange (ETDEWEB)

During LOCA(Loss of Coolant Accident), emergency core coolant supplements form a recirculation sump and cooled core and containment. When the double ended guillotine Break (DEGB) at the hot leg near steam generator, due to the jet impingement discharge flow, the debris could be potentially generated at pipe or wall nearby steam generator and be transported to the recirculation sump. Therefore, the debris could be accumulated and be clogged in the recirculation sump screen. If debris blocked the sump screen, the pressure drop increased at the screen so as to increase the pressure loss of ECCS (Emergency Core Cooling System) pump NPSH (Net positive suction head). It is potentially influenced to decrease the long-term cooling capability of the recirculation sump. The recirculation sump screen clogging accident has happened in BWR at 1990. Considering the important of safety, US NRC published Regulatory Guide 1.82 Rev.3 incorporating the R and D findings and experiences in 2003. NEI ...

2010-05-15

199

Study of the origin of elements of the uranium-235 family observed in excess in the vicinity of the experimental nuclear EL4 reactor under dismantling. Lessons got at this day and conclusions; Etude de l'origine des elements de la famille de l'uranium-235 observes en exces dans les environs du reacteur nucleaire experimental EL4 en cours de demantelement. Enseignements retires a ce jour et conclusion  

Energy Technology Data Exchange (ETDEWEB)

This study resumes the discovery of an excess of actinium 227 found around by EL4 nuclear reactor actually in dismantling. The search for the origin of this excess revealed a real inquiry of investigation during three years. Because a nuclear reactor existed in this area a particular attention will have concerned this region. The doubt became the line of conduct to find the answer to the human or natural origin of this excess. Finally and against any evidence, it appears that the origin of this phenomenon was natural, consequence of the particular local geology. The detail of the different investigations is given: search of a possible correlation with the composition of elevations constituent of lanes, search (and underlining) of new sites in the surroundings of the Rusquec pond and the Plouenez station, study of the atmospheric deposits under winds of the nuclear power plant and in the east direction, search of a possible relationship with the gaseous effluents of the nuclear power ...

2007-07-01

200

Point-contact Andreev-reflection spectroscopy in MgB{sub 2}: The role of substitutions  

Energy Technology Data Exchange (ETDEWEB)

We summarize the results of point-contact Andreev-reflection (PCAR) spectroscopy in MgB{sub 2} doped by chemical substitutions, either magnetic (Mn) or non-magnetic (Al,C), obtained by us and by other groups in the last four years. Despite the variety of samples used (crystals and polycrystals of various origin) and some minor differences in the experimental techniques, these measurements have directly provided a complete and consistent picture of the effects of chemical substitutions on the gaps of MgB{sub 2} shedding light on other relevant parameters (scattering rates, DOSs) affected by doping. In Al-doped crystals and polycrystals, the gap amplitudes {delta}{sub {sigma}} and {delta}{sub {pi}} - obtained through a two-band Blonder-Tinkham-Klapwijk (BTK) fit of the Andreev-reflection conductance curves - decrease on increasing the Al content x (i.e. on decreasing the critical temperature of the contacts T{sub c}{sup A}), but remain clearly distinct with no evidence of gap merging ...

2007-06-01

201

Measurement of K x-ray intensity ratio of tin, gadolinium and dysprosium  

International Nuclear Information System (INIS)

Full text: Measurement of K_#beta# to K_#alpha# x-ray intensity ratios are important not only in the field of atomic physics, radiation physics and medical physics, but also to test the validity of assumptions made in the theoretical prediction. The intensity ratios can also give information on the effect of physical and chemical environment of the element in the compound. Many investigators have adopted a single and double reflection geometries to measure the K_#beta# to K_#alpha# x ray intensity ratios to understand the effect of physical and chemical environment on x-ray fluorescence. The targets are excited by a radioactive source of having activity of the order 100 MBq. in order to carry out accurate measurement K_#beta# to K_#alpha# x-ray intensity ratios, we have develop 2#pi# geometrical configuration method : placing a target right on the surface of the detector facing the target to measure the K shell fluorescence parameters such as fluorescence yield, ...

2003-11-01

202

Heat transfer augmentation using a magnetic fluid under the influence of a line dipole  

Energy Technology Data Exchange (ETDEWEB)

Ferrofluids have promising potential for heat transfer applications, since advective transport in a ferrofluid can be readily controlled by using an external magnetic field. However, unlike conventional free or forced convection, ferrohydrodynamic convection is not yet well characterized. A full understanding of the relationship between an imposed magnetic field, the resulting ferrofluid flow, and the temperature distribution is a prerequisite for the proper design and implementation of applications involving thermomagnetic convection. The literature variously assumes constant magnetic fields, does not completely represent the variation in the imposed field, or its descriptions are inaccurate, since the fields do not comply with the Maxwell's equations of electromagnetism. We address this by simulating two-dimensional forced convection heat transfer in a channel with a ferrofluid that is under the influence of a two-dimensional magnetic field created by a ...

2004-04-01

203

Heat transfer augmentation using a magnetic fluid under the influence of a line dipole  

International Nuclear Information System (INIS)

Ferrofluids have promising potential for heat transfer applications, since advective transport in a ferrofluid can be readily controlled by using an external magnetic field. However, unlike conventional free or forced convection, ferrohydrodynamic convection is not yet well characterized. A full understanding of the relationship between an imposed magnetic field, the resulting ferrofluid flow, and the temperature distribution is a prerequisite for the proper design and implementation of applications involving thermomagnetic convection. The literature variously assumes constant magnetic fields, does not completely represent the variation in the imposed field, or its descriptions are inaccurate, since the fields do not comply with the Maxwell's equations of electromagnetism. We address this by simulating two-dimensional forced convection heat transfer in a channel with a ferrofluid that is under the influence of a two-dimensional magnetic field created by a ...

2004-04-01

204

Ground- and space-based temperature and humidity retrievals: Statistical evaluation  

Energy Technology Data Exchange (ETDEWEB)

A near-real-time integrated temperature and water vapor sounding system has been designed and in operation since June 1993. It combines hourly data from the ground-based radio acoustic sounding system (RASS), a two-channel microwave radiometer, standard surface meteorological instruments, a lidar ceilometer, and the Aerodynamic Research Incorporated Communication, Addressing and Reporting System aboard commercial airlines with space-based data from the TIROS-N Operational Vertical Sounder (TOVS). The physical retrieval algorithm provided by the International TOVS Processing Package is used for combining the ground- and space-based temperature and humidity profiles. The first-guess profiles of temperature and humidity required by the physical retrieval algorithm are obtained by using a statistical inversion technique and the ground-based remote sensors measurements. Statistical error estimates are presented for the hourly, near-real-time, ground-, and space-based ...

1996-03-01

205

Characterization of the parameters at the origin of the chemical species hideout process at the fuel rod surface in boiling conditions  

International Nuclear Information System (INIS)

Current trends in nuclear power generation (and particularly in pressurized water reactors) are toward plant life extension and extended fuel burnup. A higher heat generation rate can induce local boiling regimes at the fuel rod surface in the hottest channels of the core, which can strongly modify the chemical environment of the cladding and influence the oxidation rate of zirconium alloys. Tests performed in out-of-pile loops under severe chemical and thermal-hydraulic conditions (nucleate boiling, higher lithium contents compared to PWRs) reveal two important phenomena: an increase of the oxidation rate of Zircaloy-4 cladding materials in 'high' lithiated environments; an enrichment of the chemical additives in the primary water (boron, lithium) at the surface of the cladding under nucleate boiling conditions. The latter phenomenon, also called 'hideout effect', is mainly controlled by some thermal hydraulic parameters such as bubble diameters and nucleation ...

1999-12-01

206

Gas-liquid two-phase flow patterns in parallel channels for fuel cells  

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into channels filled with gas (stratified flow ...

2008-09-01

207

Counter-current air-water flow in narrow rectangular channels with offset strip fins  

Energy Technology Data Exchange (ETDEWEB)

Counter-current two-phase flows of air-water in narrow rectangular channels with offset-strip fins have been experimentally investigated in a 760 mm long and 100 mm wide test section with 3.0 and 5.0 mm gap widths. The two-phase flow regime, channel-average void fractions and two-phase pressure gradients were studied. Flow regime transition occurred at lower superficial velocities of air than in the channels without fins. In the bubbly and slug flow regimes, elongated bubbles rose along the subchannel formed by fins without lateral movement. The critical void fraction for the bubbly-to-slug transition was about 0.14 for the 3 mm gap channel and 0.2 for the 5 mm gap channel, respectively. Channel-average void fractions in the channels with fins were almost the same as those in the channels without fins. Void fractions ...

2003-03-01

208

Transforming Clinic Environments into Information Workspaces for Patients  

UK PubMed Central (United Kingdom)

Although clinic environments are a primary location for exchanging information with clinicians, patients experience these spaces as harsh environments to access, use, exchange, and manage information....Full Text Available

2010-01-01

209

NASA Information Technology Requirement  

Science.gov (United States)

Appendix C Information Technology (IT) Waiver Process. Distribution. NODlS. Center Chief Information Officers. 1. Page 3. Change History ...

210

HPCC and the National Information Infrastructure: an overview.  

UK PubMed Central (United Kingdom)

The National Information Infrastructure (NII) or "information superhighway" is a high-priority federal initiative to combine communications networks, computers, databases, and consumer electronics to...Full Text Available

1995-01-01

211

Database Creation for Information Processing Methods ...  

Science.gov (United States)

Page 1. Database Creation for Information Processing Methods, ... ARL-TN-0348 May 2009 Database Creation for Information Processing Methods, ...

2009-05-01

212

A Human-Centered Design and Evaluation Framework for Information Search  

UK PubMed Central (United Kingdom)

Information search in a distributed environment is an interactive process between the user and the artifact. How the information is distributed across the user and the artifact determines the efficacy...Full Text Available

2005-01-01

213

Universality for the Noisy Slepian-Wolf Problem Via Spatial Coupling  

CERN Document Server

We consider a noisy Slepian-Wolf problem where two correlated sources are separately encoded and transmitted over two independent binary memoryless symmetric channels. Each channel capacity is assumed to be characterized by a single parameter which is not known at the transmitter. The receiver has knowledge of both the source correlation and the channel parameters. We call a system universal if it retains near-capacity performance without channel knowledge at the transmitter. Kudekar et al. recently showed that terminated low-density parity-check (LDPC) convolutional codes (a.k.a. spatially-coupled LDPC ensembles) can have belief-propagation thresholds that approach their maximum a-posteriori thresholds. This was proven for binary erasure channels and shown empirically for binary memoryless symmetric channels. They also conjectured that the principle of spatial ...

2011-01-01

214

Design and x-ray crystal structures of high-potency nonsteroidal glucocorticoid agonists exploiting a novel binding site on the receptor  

Energy Technology Data Exchange (ETDEWEB)

Crystallography and computer modeling have been used to exploit a previously unexplored channel in the glucocorticoid receptor (GR). Highly potent, nonsteroidal indazole amides showing excellent complementarity to the channel were designed with the assistance of the computational technique AlleGrow. The accuracy of the design process was demonstrated through crystallographic structural determination of the GR ligand-binding domain-agonist complex of the D-prolinamide derivative 11. The utility of the channel was further exemplified through the design of a potent phenylindazole in which structural motifs, seen to interact with the traditional GR ligand pocket, were abandoned and replaced by interactions within the new channel. Occupation of the channel was confirmed with a second GR crystal structure of this truncated D-alaninamide derivative 13. Compound 11 displays properties ...

2010-09-17

215

Temperature-dependent properties of semiconductor quantum dots in coherent regime; Temperaturabhaengige Eigenschaften einzelner Halbleiter-Quantenpunkte im Kohaerenten Regime  

Energy Technology Data Exchange (ETDEWEB)

Recently, the public has become aware of keywords like ''Quantum computer'' or ''Quantum cryptography''. Regarding their potential application in solid state based quantum information processing and their overall benefit in fundamental research quantum dots have gained more and more public interest. In this context, quantum dots are often referred to as ''artificial atoms'', a term subsuming their physical properties quite nicely and emphasizing the huge potential for further investigations. The basic mechanism to be considered is the theoretical model of a two-level system. A quantum dot itself represents this kind of system quite nicely, provided that only the presence or absence of a single exciton in the ground state of that structure is regarded. This concept can also be expanded to the presence of two excitons (bi-exciton). Transitions between the ...

2009-10-15

216

Thermal-hydraulic characteristics of boiling water two-phase flow in narrow horizontal rectangular channel  

International Nuclear Information System (INIS)

Heat transfer and flow characteristics of water boiling flow were experimentally investigated in narrow horizontal rectangular channels with the gaps of 0.6mm-2.03mm. The heat transfer of two-phase boiling flow was weakend in smaller gap. The two-phase friction pressure drop decreased with the gap size and the two-phase friction multipliers were smaller compared with those in normal channels. Correlations to predict te boiling heat transfer coefficients were obtained. (author)

2003-05-28

217

Microstructure, texture and mechanical properties of the magnesium alloy AZ31 processed by ECAP  

Energy Technology Data Exchange (ETDEWEB)

To investigate the influence of equal channel angular pressing on the microstructure and texture of the magnesium alloy AZ31, electron backscattering diffraction and well as neutron diffraction experiments were carried out. Through these experiments it was possible to trace the microstructure and texture evolution with strain accumulated with the increasing number of equal channel angular pressing passes. It was further demonstrated by subsequent compression tests that the microstructural changes produced by equal channel angular pressing have a beneficial effect on both the compressive strength and ductility of AZ31. (orig.)

2008-01-15

218

Heat rejection system  

Energy Technology Data Exchange (ETDEWEB)

A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water. 5 figs.

1980-01-22

219

Functionalized luminescent oxide nanoparticles for sodium channel imaging at the single molecule level  

Science.gov (United States)

Lanthanide-ion doped oxide nanoparticles were functionalized for use as fluorescent biological labels. These nanoparticles are synthesized directly in water which facilitates their functionalization, and are very photostable without emission intermittency. Nanoparticles functionalized with guanidinium groups act as artificial toxins and specifically target sodium channels. They are individually detectable in cardiac myocytes, revealing a heterogeneous distribution of sodium channels. Functionalized oxide nanoparticles appear as a novel tool particularly well adapted to long-term single-molecule tracking.

2005-04-01

220

Coupled-channels calculations of elastic and inelastic scattering  

Energy Technology Data Exchange (ETDEWEB)

Cross sections for the elastic and inelastic scattering of /sup 16/O on /sup 58/Ni, /sup 88/Sr, /sup 40/Ca, and /sup 48/Ca have been calculated in a coupled-channels treatment, including the low-lying 2/sup +/ and 3/sup /minus// states of both projectile and target. Real, energy-independent ion-ion potentials and form factors were used, and fusion was simulated by ingoing wave boundary conditions in all channels. The agreement with the measured scattering data is qualitatively as good as obtained in previous optical-model calculations.

1989-07-01

221

Coupled-channels calculations of elastic and inelastic scattering  

International Nuclear Information System (INIS)

Cross sections for the elastic and inelastic scattering of "1"6O on "5"8Ni, "8"8Sr, "4"0Ca, and "4"8Ca have been calculated in a coupled-channels treatment, including the low-lying 2"+ and 3"- states of both projectile and target. Real, energy-independent ion-ion potentials and form factors were used, and fusion was simulated by ingoing wave boundary conditions in all channels. The agreement with the measured scattering data is qualitatively as good as obtained in previous optical-model calculations.

222

Vascular ATP-sensitive potassium channels are over-expressed and partially regulated by nitric oxide in experimental septic shock  

British Library Electronic Table of Contents (United Kingdom)

Purpose To study the activation and expression of vascular (aorta and small mesenteric arteries) potassium channels during septic shock with or without modulation of the NO pathway. Methods Septic shock was induced in rats by peritonitis. Selective inhibitors of vascular KATP (PNU-37883A) or BKCa [iberiotoxin (IbTX)] channels were used to demonstrate their involvement in vascular hyporeactivity. Vascular response to phenylephrine was measured on aorta and small mesenteric arteries mounted on a wire myograph. Vascular expression of potassium channels was studied by PCR and Western blot, in the presence or absence of 1400W, an inducible NO synthase (iNOS) inhibitor. Aortic activation of the transcriptional factor nuclear factor-kappaB (NF-?B) was assessed by electrophoretic mobility shift as...

2011-01-01

223

Unified Analysis of the Average Gaussian Error Probability for a Class of Fading Channels  

CERN Document Server

This paper focuses on the analysis of average Gaussian error probabilities in certain fading channels, i.e. we are interested in E[Q((p {\\gamma})^(1/2))] where Q(.) is the Gaussian Q-function, p is a positive real number and {\\gamma} is a nonnegative random variable. We present a unified analysis of the average Gaussian error probability, derive a compact expression in terms of the Lauricella FD^(n) function that is applicable to a broad class of fading channels, and discuss the relation of this expression and expressions of this type recently appeared in literature. As an intermediate step in our derivations, we also obtain a compact expression for the outage probability of the same class of fading channels. Finally, we show how this unified analysis allows us to obtain novel performance analytical results.

2011-01-01

224

Transformation of Verapamil by Cunninghamella blakesleeana  

UK PubMed Central (United Kingdom)

A filamentous fungus, Cunninghamella blakesleeana AS 3.153, was used as a microbial model of mammalian metabolism to transform verapamil, a calcium channel antagonist. The metabolites...Full Text Available

2004-05-01

225

Thermalhydraulic Characteristics for Wolsung-1 after retubing  

International Nuclear Information System (INIS)

The ROP margin in a CANDU reactor is decreasing over time due to the Primary Heat-Transport System (PHTS) aging effect. Adjustment of the ROP trip setpoint is required to maintain a high trip-probability and ROP trip effectiveness. Especially, for Wolsong-1, which is scheduled to change the old pressure tubes in 2009, the trend of ROPT after the retubing should be reevaluated. Before setting a ROPT, the main thermal characteristics including Critical Channel Power (CCP) should be calculated by the NUCIRC code. In this paper, the thermalhydraulic evaluation for Wolsung-1 was conducted with the updated Wolsung-1 PHTS data. Specifically, for the case of 0 EFPY (Effective Full Power Year) and 11 EFPY after the retubing, the distribution of the channel flow rate, channel exit quality, critical channel power, and critical power ratio (CPR) of the Wolsong-1 aged plant are calculated

2009-05-01

226

Subcooled Flow Boiling in a Minichannel  

British Library Electronic Table of Contents (United Kingdom)

It has been considered that dry-out occurs easily in boiling heat transfer for a small channel, a mini- or microchannel, because the channel was easily filled with coalescing vapor bubbles. In the present study, the experiments of subcooled flow boiling of water were performed under atmospheric conditions for a horizontal rectangular channel for which the size is 1 mm height and 1 mm width, with a flat heating surface of 10 mm length and 1 mm width placed on the bottom of the channel. The heating surface has a top of copper heating block and is heated by ceramic heaters. In the high heat flux region of nucleate boiling, about 70-80% of the heating surface was covered with a large coalescing bubble and the boiling reached critical heat flux as observed by high-speed video. In the beginning ...

2011-01-01

227

Secure Direct Communication Based on Non-Orthogonal Entangled Pairs and Local Measurement  

Science.gov (United States)

We propose a quantum secure direct communication scheme based on non-orthogonal entangled pairs and local measurement. In this scheme, we use eight non-orthogonal entangled pairs to act as quantum channels. Due to the non-orthogonality of the quantum channels, the present protocol can availably prohibit from all kinds of valid eavesdropping and acquire a secure quantum channel. By local measurement, the sender acquires a secret random sequence. The process of encoding on the random sequence is identical to the one in one-time-pad. So the present protocol is secure. Even for a highly lossy channel, our scheme is also valid. The scheme is feasible with present-day techniques.

2008-12-01

228

Rough surface  

International Nuclear Information System (INIS)

For the determination of the thermal-hydraulic performances of rough surfaces, the method of evaluation is particularly important. In order to increase confidence in the results, a new evaluation procedure was introduced. This procedure is based on the transformation of simple channel experimental results to equal boundary conditions, and on the suitable application and confirmation of these transformed values in more complicated flow channel geometries. Existing methods, applied to the results obtained in an annular channel, do not fulfil all the transformation requirements. Thus a new, more complete transformation method, which uses the turbulent eddy diffusivity model, was developed. To check the quality of this transformation, within the scope of the new evaluation procedure, the results of experimental investigation in annular channels and in a bundle of hexagonal geometry were used together with ...

2009-08-01

229

Refilling Intracellular Calcium Stores  

UK PubMed Central (United Kingdom)

Within the cardiac cell, the movements of calcium ions are tightly regulated by a number of regulatory proteins including pumps, and channels. The sarcoplasmic reticulum (SR) is in large part...Full Text Available

2010-01-01

230

Physical and mathematical description of Nuclear Weapons Identification System (NWIS) signatures  

Energy Technology Data Exchange (ETDEWEB)

This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the {sup 252}Cf source ionization chamber; (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the full five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt%, {sup 235}U) metal casting for storage are presented to illustrate the various time and ...

1997-09-26

231

Physical and Mathematical Description of Nuclear Weapons Identification System (NWIS) Signatures  

Energy Technology Data Exchange (ETDEWEB)

This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the 252Cf source ionization chamber (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the fill five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt 0/0, 235U) metai casting for storage are presented to illustrate the various time and frequency ...

1997-09-26

232

Perfect and Incompressible Fluid Flow in Turbomachines.  

Science.gov (United States)

A method for calculating flow through an airfoil cascade drawn on a surface of revolution is discussed. The three-dimensional flow was assumed to be represented by part-channels of varying width. The basic equations are the equation of continuity and the ...

1974-01-01

233

Multi-channel customer management: Delighting consumers, driving efficiency  

British Library Electronic Table of Contents (United Kingdom)

In today's maturing consumer markets, emphasis is shifting from straightforward sales to a more holistic approach to customer life cycle management, with a stronger emphasis on how sales are generated and service provided all along the customer journey. Effectively managing these different marketing, sales and service channels poses a significant challenge. Companies need new strategies, structures, processes and tools to deliver customer value across all channels. A multi-channel, integrative customer model that delivers customer value and significant return on investment (ROI) requires both a strong understanding of customer preferences and behaviours and a robust IT architecture that supports the overarching customer relationship management (CRM) strategy. Even those organizations that ...

2010-01-01

234

LCP-10 Intelligibility of Oxygen Masks and Microphones in ...  

Science.gov (United States)

... JTIDS) LPC-10 voice channel has been an important facet of a larger ongoing in-house research task on Digital Audio Technology for Aircraft ...

1988-10-24

235

Ion channels, transporters, and pumps as targets for heart failure  

UK PubMed Central (United Kingdom)

Congestive heart failure (CHF) is a leading cause of morbidity and mortality. CHF is marked by atrial and ventricular enlargement and reduced cardiac contractility, as well as an association...Full Text Available

2009-10-01

236

Integrated Optics Interdigitated-Electrode Switches  

Science.gov (United States)

... thus can function as switches -6 ... Akkari, "Optical Channel Waveguide Switch and Coupler ... Wide-Band Guided Wave Acousto-Optic Bragg Diffraction ...

1989-12-31

237

Heat transfer augmentation through wall-shape-induced flow destabilization  

Energy Technology Data Exchange (ETDEWEB)

Experiments on heat transfer augmentation in a rectangular cross-section water channel are reported. The channel geometry is designed to excite normally damped Tollmein-Schlichting modes in order to enhance mixing. In this experiment, a hydrodynamically fully developed flow encounters a test section where one channel boundary is a series of periodic, saw-tooth, transverse grooves. Free shear layers span the groove openings, separating the main channel flow from the circulating vortices contained within each cavity. The periodicity length of the grooves is equal to one-half of the expected wavelength of the most unstable mode. The remaining channel walls are flat, and the channel has an aspect ratio of 10:1. Experiments are performed over the Reynolds number range of 300 to 15,000. Streakline flow visualization shows that the flow is steady at the entrance, but ...

1990-05-01

238

Heat transfer augmentation of mixed convection through vortex shedding from an inclined plate in a vertical channel containing heated blocks  

Energy Technology Data Exchange (ETDEWEB)

A numerical analysis is made of the unsteady flow and heat transfer characteristics of mixed convection in a vertical block-heated channel with and without installing an inclined plate above an upstream block. Parameter studies including the inclined plate angle, Reynolds number (ranging from 260 to 530), and Grashof number (in the range of 0--3,200,000) on heat transfer performance have been explored in detail. The results show that the installation of an inclined plate in the vertical block-heated channel can effectively augment the blocks` heat transfer performance in the channel. This can be applied to heat exchangers.

1998-02-06

239

GERT" GRAPHICAL EVALUATION AND REVIEW TECHNIQUE  

Science.gov (United States)

of a stochastic network can be a. PERT-type network. After the terminal countdown, ...... pictorial representation of a single channel queueing system ...

240

Forced convective heat transfer in cross-corrugated solar air heaters  

Science.gov (United States)

Forced convective heat transfer in a cross-corrugated channel solar air heater has been studied experimentally using air as a working fluid. The channel was formed by two transversely positioned corrugated sheets and two flat thermally insulated side walls. One corrugated sheet was heated by a radiant heater, while the other was thermally insulated. The fluid velocity and temperature, and the wall temperature and the local heat flux across the heated corrugated sheet were measured for a variety of operating flow rates. Experimental results for the channel geometry have yielded the correlation Nu = 0.0743 (Re)[sup 0.76]. This heat-transfer coefficient is about 2.8 times that of a smooth flat channel. The experiments showed that local heat transfer rate was smaller on the valley of the corrugation than that on the peak. The ratio of the local heat transfer rates on the two locations was related to the ...

1994-11-01

241

Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated for a wide range of modified Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.15win0.16m/s) using a flow rate control valve so that Reynolds number was always about Re=1500. Experiments were conducted...

2010-01-01

242

Evaluation of Upland Disposal of John F. Baldwin Ship ...  

Science.gov (United States)

... Accession Number : ADA270425. Title : Evaluation of Upland Disposal of John F. Baldwin Ship Channel Sediment. Descriptive Note : Final rept.,. ...

1993-07-01

243

Channel Rehabilitation: Processes, Design, and ...  

Science.gov (United States)

... time. The Paleozoic Era ended only 248 million years ago, the Mesozoic Era ended only 65 million years ago, and so on. ...

1999-07-01

245

Battle Management Command and Control (BMC2) Human ...  

Science.gov (United States)

... For communication systems that employ spatial audio technology to separate intercom and/or radio channels, configurations of the spatial ...

2005-06-01

246

A two-phase flow regime map for a MAPLE-type nuclear research reactor fuel channel: Effect of hexagonal finned bundle  

Energy Technology Data Exchange (ETDEWEB)

A two-phase flow regime map is developed experimentally and theoretically for a vertical hexagonal flow channel with and without a 36-finned rod hexagonal bundle. This type of flow channel is of interest to MAPLE-type nuclear research reactors. The flow regime maps are determined by visual observations and observation of waveforms shown by a capacitance-type void fraction meter. The experimental results show that the inclusion of the finned hexagonal bundle shifts the flow regime transition boundaries toward higher water flow rates. Existing flow regime maps based on pipe flow require slight modifications when applied to the hexagonal flow channel with and without a MAPLE-type finned hexagonal bundle. The proposed theoretical model agrees well with experimental results.

1997-05-01

247

A two-phase flow regime map for a MAPLE-type nuclear research reactor fuel channel: Effect of hexagonal finned bundle  

International Nuclear Information System (INIS)

A two-phase flow regime map is developed experimentally and theoretically for a vertical hexagonal flow channel with and without a 36-finned rod hexagonal bundle. This type of flow channel is of interest to MAPLE-type nuclear research reactors. The flow regime maps are determined by visual observations and observation of waveforms shown by a capacitance-type void fraction meter. The experimental results show that the inclusion of the finned hexagonal bundle shifts the flow regime transition boundaries toward higher water flow rates. Existing flow regime maps based on pipe flow require slight modifications when applied to the hexagonal flow channel with and without a MAPLE-type finned hexagonal bundle. The proposed theoretical model agrees well with experimental results.

1997-01-01

248

A note on the flow and heat transfer enhancement in a channel with built-in winglet pair  

International Nuclear Information System (INIS)

Counter rotating longitudinal vortices produced by winglet in a channel are known to enhance heat transfer. In the present investigation the flow structure and heat-transfer enhancement by a winglet pair of non-zero thickness has been studied. A delta winglet pair type vortex generator is placed in a hydrodynamically developed and thermally developing laminar channel flow. Computations are done by solving the unsteady, three-dimensional, incompressible Navier-Strokes equations and energy equation using a modified Marker-and-Cell (MAC) method. The flow structure is complex and consists of main, corner and induced vortices. It is observed that as compared to a channel without winglets, the heat transfer is enhanced by 33% when single winglet is used and by 67% when a winglet pair is employed. Effects of thickness of the winglets and Reynolds number on the heat transfer augmentation are presented.

2007-04-01

249

A comparison of benthic biodiversity in the North Sea, English ...  

Science.gov (United States)

A comparison of benthic biodiversity in the North Sea, English Channel, and Celtic Seas. ICES J. Mar. Sci./J. Cons. int. Explor. Mer 56: 228-246. ...

253

48 CFR 352.239-72 - Security requirements for Federal information technology resources.  

Science.gov (United States)

...requirements for Federal information technology resources. 352.239-72...requirements for Federal information technology resources. As prescribed...Requirements for Federal Information Technology Resources (January...

2010-10-01

254

48 CFR 2452.239-71 - Information Technology Virus Security.  

Science.gov (United States)

... 2010-10-01 true Information Technology Virus Security. 2452...Clauses 2452.239-71 Information Technology Virus Security. As prescribed...the following clause: Information Technology Virus Security (FEB...

2010-10-01

255

48 CFR 1252.239-71 - Information technology security plan and accreditation.  

Science.gov (United States)

...2010-10-01 false Information technology security plan and accreditation...Clauses 1252.239-71 Information technology security plan and accreditation...following provision: Information Technology Security Plan and...

2010-10-01

256

To Repair or to Rebuild? Analyzing Personnel Security ...  

Science.gov (United States)

... Screening Adjudication Monitoring Applicants of Information Behavior II I Conducting Investigations ... Applicants of Information Behavior Conducting ...

1988-09-01

257

The Detailing Process Information Technology and NEC ...  

Science.gov (United States)

... Accession Number : ADB323076. Title : The Detailing Process Information Technology and NEC Utilization. Descriptive Note : Final rept. ...

2006-09-01

258

National Agricultural Library:  

Science.gov (United States)

Featured Collections Featured collections are information sources that use federated search or are known for presenting exceptional, authoritative information for...

2011-08-19

259

Lifting the Fog of Corporate Information Management  

Science.gov (United States)

... forces. These small forces must have the same information management capabilities as are currently 32 Page 40. available ...

1993-04-01

260

Information Warfare: Evaluation of Operator Information ...  

Science.gov (United States)

... as the now-famous Missionaries and Cannibals task: three missionaries and three cannibals must cross a river. They have ...

1997-10-01

261

Information Technology Glossary - NASA  

Science.gov (United States)

Information Technology Glossary of Terms. Applets: Programs that run inside net browsers, usually in Java and typically involving modestly interactive ...

262

Enabling Battlefield Visualization: An Agent-Based Information ...  

Science.gov (United States)

... such as discovery, capabilities registration, lookup, and a ... Java- based toolkit for creating ... Multisensor, Multisource Information Fusion: Architectures ...

2005-06-01

263

Defense Science Board 2006 Summer Study of Information ...  

Science.gov (United States)

... Those communications and information management capabilities required in the battlefield should be part of the weapon system. ...

2007-04-01

264

DIGITAL LIBRARIES: IMPACT ON SCIENCE ... - MUSPIN - NASA  

Science.gov (United States)

digital libraries, which was identified as a national challenge in the Information ... The linkages between the many digital libraries and information services are ...

265

Computer and Network Security Information  

Science.gov (United States)

Computer And Network Security: Information For Everyone: This presentation was originally prepared as the 14th talk in a series known as "The Programmer's ...

266

Codifying Information Assurance Controls for Department of ...  

Science.gov (United States)

... listed certifications are vendor (CCNA) and Server Plus (Server neutral such as the Certified Information S ... CCNA ITIL NET+ GSEC SECURITY+ ...

2010-03-01

267

Information systems, databases (www.onderzoekinformatie.nl)  

Wastenet

...Identification - ETI Food & Biobased Research (WUR) Freudenthal Institute - FIsme (UU) Holst Centre IKM Engineering Ltd Information Retrieval and Information Systems (KUN) Information Systems - INS Information Technology Group (WUR) Institute for Computing and Information Sciences - ICIS (KUN) Institute of Health Policy and Management (EUR) ...

268

Research on regimes transition of the boiling water two-phase flow in horizontal rectangular narrow heated channels  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of ...

2005-07-01

269

Research on regimes transition of the boiling water two-phase flow in horizontal rectangular narrow heated channels  

International Nuclear Information System (INIS)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of ...

2005-10-02

270

The Dixmier-Moeglin equivalence and a Gel'fand-Kirillov problem for Poisson polynomial algebras  

CERN Document Server

The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum matrices, quantum symplectic and euclidean spaces, quantum symmetric and antisymmetric matrices. For a similarly large class of Poisson polynomial rings, it is proved that the quotient field of the algebra (respectively, of any Poisson prime factor ring) is a rational function field $F(x_1,...,x_n)$ over the base field (respectively, over an extension field of the base field) with $\\{x_i,x_j\\}= \\lambda_{ij} x_ix_j$ for suitable scalars $\\lambda_{ij}$, thus establishing a ...

2007-01-01

271

Superconducting gravity gradiometer for sensitive gravity measurements. I. Theory  

Energy Technology Data Exchange (ETDEWEB)

Because of the equivalence principle, a global measurement is necessary to distinguish gravity from acceleration of the reference frame. A gravity gradiometer is therefore an essential instrument needed for precision tests of gravity laws and for applications in gravity survey and inertial navigation. Superconductivity and SQUID (superconducting quantum interference device) technology can be used to obtain a gravity gradiometer with very high sensitivity and stability. A superconducting gravity gradiometer has been developed for a null test of the gravitational inverse-square law and space-borne geodesy. Here we present a complete theoretical model of this instrument. Starting from dynamical equations for the device, we derive transfer functions, a common mode rejection characteristic, and an error model of the superconducting instrument. Since a gradiometer must detect a very weak differential gravity signal in the midst of large platform accelerations and other environmental ...

1987-06-15

272

Quantum geometrodynamics of the Bianchi IX cosmological model  

Energy Technology Data Exchange (ETDEWEB)

The canonical quantum theory of gravity-quantum geometrodynamics (QG)-is applied to the homogeneous Bianchi type IX cosmological model. As a result, a framework for the quantum theory of homogeneous cosmologies is developed. We show that the theory is internally consistent and prove that it possesses the correct classical limit (the theory of general relativity). To emphasize the special role that the constraints play in this new theory, we compare it to the traditional ADM square-root and Wheeler-DeWitt quantization schemes. We show that, unlike traditional approaches, QG leads to a well-defined Schroedinger equation for the wavefunction of the universe that is inherently coupled to the expectation value of the constraint equations. This coupling to the constraints is responsible for the appearance of a coherent spacetime picture. Thus, the physical meaning of the constraints of the theory is quite different from Dirac's interpretation. In light of this ...

2006-07-01

273

Quantum geometrodynamics of the Bianchi IX cosmological model  

International Nuclear Information System (INIS)

The canonical quantum theory of gravity-quantum geometrodynamics (QG)-is applied to the homogeneous Bianchi type IX cosmological model. As a result, a framework for the quantum theory of homogeneous cosmologies is developed. We show that the theory is internally consistent and prove that it possesses the correct classical limit (the theory of general relativity). To emphasize the special role that the constraints play in this new theory, we compare it to the traditional ADM square-root and Wheeler-DeWitt quantization schemes. We show that, unlike traditional approaches, QG leads to a well-defined Schroedinger equation for the wavefunction of the universe that is inherently coupled to the expectation value of the constraint equations. This coupling to the constraints is responsible for the appearance of a coherent spacetime picture. Thus, the physical meaning of the constraints of the theory is quite different from Dirac's interpretation. In light of this ...

2006-07-01

274

Perturbative Quantum Gravity and Yang-Mills Theories in de Sitter Spacetime  

CERN Document Server

This thesis consists of three parts. In the first part we review the quantization of Yang-Mills theories and perturbative quantum gravity in curved spacetime. In the second part we calculate the Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge. In the third part we investigate the physical equivalence of covariant Wightman graviton two-point function with the physical graviton two-point function. The Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge are infrared (IR) divergent in de Sitter spacetime. We point out, that if we regularize these divergences by introducing a finite mass and take the zero mass limit at the end, then the modes responsible for these divergences will not contribute to loop diagrams in computations of time-ordered products in either Yang-Mills theories or perturbative quantum gravity. We ...

2011-01-01

275

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 performance is sensitive to vigilance and number of training set ...

1992-10-01

276

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 network gives the best results, with 100% within-class, between-class, and ...

1993-01-01

277

Critical assessment of the Schroedinger picture of quantum mechanics  

Energy Technology Data Exchange (ETDEWEB)

We provide an example in which the Heisenberg and the Schroedinger pictures of quantum mechanics give different results, thus confirming the statement of P.A.M. Dirac that the two pictures may lead to inequivalent results. We consider a one-dimensional nonrelativistic charged harmonic oscillator (frequency {omega}{sub 0} and mass m), and take into account the action of the radiation reaction and the vacuum electromagnetic forces on the charged oscillator. We show that the Heisenberg picture gives the correct value, {Dirac_h}{omega}{sub 0}/2, for the ground state energy of the harmonic oscillator in both cases of classical and quantized vacuum fields. In the case of the Schroedinger picture, considering classical vacuum fields, and using a simple calculation for the classical radiation reaction force that is valid in the limit of large mass (mc{sup 2} >> {Dirac_h}{omega}{sub 0}), we obtain the value {Dirac_h}{omega}{sub 0} for the ground state energy ...

2002-12-16

278

Anomalous tensor magnetic moments and form factors of the proton in the self-consistent chiral quark-soliton model  

Science.gov (United States)

We investigate the form factors of the chiral-odd nucleon matrix element of the tensor current. In particular, we aim at the anomalous tensor magnetic form factors of the nucleon within the framework of the SU(3) and SU(2) chiral quark-soliton model. We consider 1/N{sub c} rotational corrections and linear effects of SU(3) symmetry breaking with the symmetry-conserving quantization employed. We first obtain the results of the anomalous tensor magnetic moments for the up and down quarks: {kappa}{sub T}{sup u}=3.56 and {kappa}{sub T}{sup d}=1.83, respectively. The strange anomalous tensor magnetic moment is yielded to be {kappa}{sub T}{sup s}=0.2{approx}-0.2, that is compatible with zero. We also calculate the corresponding form factors {kappa}{sub T}{sup q}(Q{sup 2}) up to a momentum transfer Q{sup 2{<=}}1 GeV{sup 2} at a renormalization scale of 0.36 GeV{sup 2}.

2010-09-01

279

Absolute spacetime the twentieth century ether  

CERN Document Server

All gauge theories need ``something fixed'' even as ``something changes.'' Underlying the implementation of these ideas all major physical theories make indispensable use of an elaborately designed spacetime model as the ``something fixed,'' i.e., absolute. This model must provide at least the following sequence of structures: point set, topological space, smooth manifold, geometric manifold, base for various bundles. The ``fine structure'' of spacetime inherent in this sequence is of course empirically unobservable directly, certainly when quantum mechanics is taken into account. This issue is at the basis of the difficulties in quantizing general relativity and has been approached in many different ways. Here we review an approach taking into account the non-Boolean properties of quantum logic when forming a spacetime model. Finally, we recall how the fundamental gauge of diffeomorphisms (the issue of general covariance vs coordinate conditions) raised deep ...

1999-01-01

280

Use of signal delay of one of detectors in two-channel radiometric flaw detector  

International Nuclear Information System (INIS)

A possibility is considered or reducing the surface heterogeneity effect of an item being tested on the result of radiation flaw detection by means of signal delay of one of detectors in a two-channel radiometric flaw detector. The exposure of a translationally moving item has been studied as well as an external exposure of a rotating hollow item.

281

Unique Bell-shaped Voltage-dependent Modulation of Na+ Channel Gating by Novel Insect-selective Toxins from the Spider Agelena orientalis*  

UK PubMed Central (United Kingdom)

Spider venoms provide a highly valuable source of peptide toxins that act on a wide diversity of membrane-bound receptors and ion channels. In this work, we report isolation, biochemical analysis, and...Full Text Available

2010-06-11

282

Two-phase fluid flow measurements in small diameter channels using real-time neutron radiography  

International Nuclear Information System (INIS)

A series of real-time, neutron radiography, experiments are ongoing at the Texas A and M Nuclear Science Center Reactor (NSCR). These tests determine the resolving capabilities for radiographic imaging of two phase water and air flow regimes through small diameter flow channels. Though both film and video radiographic imaging is available, the real-time video imaging was selected to capture the dynamic flow patterns with results that continue to improve. (author)

1994-04-05

283

Two-phase flow patterns and frictional pressure gradients in a small, horizontal, rectangular channel  

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow patterns and frictional pressure gradients in flow in small, rectangular channels are being studies as part of a larger research program addressing phase-change heat transfer of pure refrigerants and refrigerant mixtures in plate-fin heat exchangers. Small rectangular flow channels were selected as representative of plain fin geometries. The particular channel reported herein has dimensions of 19.05 {times} 3.18 mm. Adiabatic flows of air/water mixtures, with the flow channel horizontal and the channel exit at near-atmospheric conditions, were utilized in the experiments. Analysis and interpretation of the pressure data relative to observed flow pattern transitions led to an objective method for determining the plug/bubble-to-slug flow transition. This method, together with visual observations, supplemented with photographic data, was used to develop a flow pattern ...

1990-05-01

284

The software for the USB-based multi-channel analyzer system  

International Nuclear Information System (INIS)

A new type of multi-channel analyzer system is introduced, which takes advantage of Universal Serial Bus to communicate with computer and gets the merit of fast speed, universality and Plug and Play. The authors discussed the framework of the system, primary functions, display of spectrum date and the way of communication with hardware. The environment of the program is Visual Basic 6.0

2002-07-01

285

Stability of the advective flow in a horizontal rectangular channel with adiabatic boundaries  

British Library Electronic Table of Contents (United Kingdom)

The steady-state advective flow in a long horizontal rectangular channel with rigid adiabatic boundaries in the presence of a uniform longitudinal pressure gradient is investigated. The stability of this flow with respect to perturbations of various types is studied. The dependence of the critical Rayleigh number on the Prandtl number is found for various aspect ratios.

2011-01-01

286

Pore properties and pharmacological features of the P2X receptor channel in airway ciliated cells  

UK PubMed Central (United Kingdom)

Airway ciliated cells express an ATP-gated P2X receptor channel of unknown subunit composition (P2Xcilia) which is modulated by Na+ and by long exposures to ATP. P2Xcilia...Full Text Available

2006-03-15

287

Nanophotonic components utilizing channel plasmon polaritons  

Science.gov (United States)

Channel plasmon polaritons (CPPs) propagating along the bottom of subwavelength grooves cut into a metal surface were recently shown to exhibit strong confinement combined with low propagation loss, a feature that makes this guiding configuration very promising for the realisation of ultra-compact photonic components. Here, the results of our investigations of CPP guiding by V-grooves cut into gold are presented, demonstrating efficient large-angle bending and splitting of radiation as well as waveguide-ring resonators and Bragg grating filters.

2008-08-01

288

MIZAR mz8310  

Science.gov (United States)

The mz8310 device support module provides support for the following record types: event, pulseCounter, pulseDelay, and pulseTrain. No driver support is needed. Up to 4 mz8310 modules are supported. Each 8310 module contains 10 channels, which are identified as signals O,...9. Each channel is individually configurable. Each mz83 10 has two Am9513 Timing Controller chips. Each Am9513 has 5 counters.

1992-07-09

289

K Depletion Enhances the Extracellular Ca2+-Induced Inhibition of the Apical K Channels in the Mtal of Rat Kidney  

UK PubMed Central (United Kingdom)

We have shown previously that raising extracellular Ca2+ inhibited the apical 70-pS K channel in the thick ascending limb (TAL; Wang, W.H., M. Lu, and S.C. Hebert. 1996. Am....Full Text Available

2002-01-01

290

Influence of defects in compound single crystals on the critical angle of planar channeling  

Energy Technology Data Exchange (ETDEWEB)

The theoretical treatment of the relation between the critical angle of planar channeling and the characteristics of crystal lattice defects is carried out. The predictions are made about some typical forms of the critical angle dependence on the mean-square static displacement produced by defects, and then these predictions are detailed for the cases of homogeneous disordering, spherical clusters of point defects and dislocation loops. Analytical results are supported by the exact computer calculations for the defects in the intermetallic A-15 compounds.

1985-01-01

291

Induced radiation during scattering of channeled electrons and positrons by point defects  

Energy Technology Data Exchange (ETDEWEB)

In scattering of channeled particles by point defects and in emission of gamma rays in the spontaneous-radiation spectral region conditions are attained where the momentum transferred to the defect is taken up by the crystal as a whole. This leads to coherent and interference effects in the radiation from the crystal defects. When the longitudinal momentum transferred is zero, an induced radiation effect appears in the transitions between the states of transverse motion.

1984-12-01

292

Higher harmonics of spontaneous radiation of ultrarelativistic channeled particles  

International Nuclear Information System (INIS)

The case of spontaneous radiation of channeled ultrarelativistic particles is considered when the dipolarity condition is not satisfied. The change of the particle longitudinal velocity affecting the maximum radiation frequency is included. The angular and frequency characteristics of the radiation for superhigh energies are studied for the first time. It is shown that there is an optimum energy at which the radiation density is maximum. The influence of the angle at which electrons enter a crystal and of the beam divergence on the radiation is investigated. The problem of quasichanneled particle radiation and also the radiation in axis-plane transitions are considered. (author).

1980-06-01

293

Effect of the adsorption-desorption process intensity on solutal convection near a drop in a horizontal channel  

British Library Electronic Table of Contents (United Kingdom)

The interaction between gravity convection and Marangoni convection in a horizontal rectangular channel filled with a liquid containing a surfactant and a drop of another liquid is numerically investigated. For large Schmidt numbers the occurring oscillatory regime of solutal convection is analyzed. In the model with a surface phase the effect of the adsorption and desorption processes on the convective flow structure is determined. The corresponding initial and boundary value problem is solved using a difference method.

2011-01-01

294

Performance evaluation for ML sequence detection in ISI channels with Gauss Markov Noise  

CERN Document Server

Inter-symbol interference (ISI) channels with data dependent Gauss Markov noise have been used to model read channels in magnetic recording and other data storage systems. The Viterbi algorithm can be adapted for performing maximum likelihood sequence detection in such channels. However, the problem of finding an analytical upper bound on the bit error rate of the Viterbi detector in this case has not been fully investigated. Current techniques rely on an exhaustive enumeration of short error events and determine the BER using a union bound. In this work, we consider a subset of the class of ISI channels with data dependent Gauss-Markov noise. We derive an upper bound on the pairwise error probability (PEP) between the transmitted bit sequence and the decoded bit sequence that can be expressed as a product of functions depending on current and previous states in the (incorrect) decoded sequence and the ...

2010-01-01

295

Low energy boron implantation in silicon: (1) reduction of channeling tail by careful alignments. (2) Transient diffusion during rapid thermal annealing  

Energy Technology Data Exchange (ETDEWEB)

An attempt was made to minimize the channeling tail by implantation along a random equivalent direction following a careful alignment of the target. In order to analytically determine the random equivalent directions, critical angles for channeling were mapped on a stereogram. Boron ions with energies of 17 and 45 keV are implanted along specified directions determined from the map. The depth distribution of the dopant is profiled by SIMS and the effects of water orientation upon the channeling tail are noted. Industrial common use of a 7/sup 0/ tilt is not optimum. However, implantation with the wafer tilted at 5.5 +/- 0.5/sup 0/ from the surface normal and rotated at 7.0 +/- 0.5/sup 0/ from a (100) plane shows the least channel-tail compared to implantation along other directions. Rapid thermal annealing (RTA) is a promising annealing method for shallow junction formation. Transient enhanced diffusion ...

1985-01-01

296

Low energy boron implantation in silicon: (1) reduction of channeling tail by careful alignments. (2) Transient diffusion during rapid thermal annealing  

International Nuclear Information System (INIS)

An attempt was made to minimize the channeling tail by implantation along a random equivalent direction following a careful alignment of the target. In order to analytically determine the random equivalent directions, critical angles for channeling were mapped on a stereogram. Boron ions with energies of 17 and 45 keV are implanted along specified directions determined from the map. The depth distribution of the dopant is profiled by SIMS and the effects of water orientation upon the channeling tail are noted. Industrial common use of a 7"0 tilt is not optimum. However, implantation with the wafer tilted at 5.5 +/- 0.5"0 from the surface normal and rotated at 7.0 +/- 0.5"0 from a (100) plane shows the least channel-tail compared to implantation along other directions. Rapid thermal annealing (RTA) is a promising annealing method for shallow junction formation. Transient enhanced diffusion of implanted ...

297

Integral cross sections of 50.5 MeV #alpha# particle inelastic scattering on 1p and (2s-1d) shell nuclei and scattering mechanisms  

International Nuclear Information System (INIS)

Obtained experimental data on integral cross sections (ICS) of inelastic scattering of 50.5 MeV #alpha# particles with the excitation of "6","7Li, "9Be, "1"2","1"3C, "1"4C, "1"4N, "2"0Ne, "2"4Mg, "2"8Si nucleus low-lying energy levels are discussed. Regularities, detected in the behaviour of ICS forward scattering for 20-90 deg angles and backscattering for 90-160 deg angles for the target-nucleus under investigation are considered. Effect of reaction open channel number on #alpha#-particle scattering ICS where n,p,d- and #alpha#-channels were considered as the main channels for all the target-nuclei, is discussed. Dependence of #alpha#-particle scattering ICS on the target-nucleus level excitation energy and dependences of reaction open channel number on the channel spin, calculated for 50.5 MeV #alpha# particles and different target nuclei are shown in the diagrams. It is noted ...

298

Evaluation of ROP Margin Effectiveness by REFORM Region  

Energy Technology Data Exchange (ETDEWEB)

In CANDU reactors, the Regional Overpower Protection Trip (ROPT) system protects the reactor against overpowers in the reactor fuel, whether due to localized peaking within the core or a general increase in core power levels. Due to Primary Heat-Transport System (PHTS) aging the ROP trip setpoint is decreasing over time. Reductions in ROP trip setpoints are required to maintain the required trip-probability and ROP trip effectiveness, and results in a decrease of the ROP margin-to-trip during normal operation. In addition, full power operation can be threatened. In this point, to recover ROPT margin, channel power needs to be redistributed. ROPT setpoint is very conservative in normal operation because distortion of regional overpower is over 1.2 times as nominal power in slow loss of regulation (SLOR). Channel power ratio (CPR) is enough low except the limiting channel of which worst case of design basis flux shape. If the ...

2007-07-01

299

Analysis and optimization of the heat transfer coefficient of a finned heat exchanger submitted to natural convection; Analise e otimizacao do coeficiente de transferencia de calor de um trocador aletado submetido a conveccao natural  

Energy Technology Data Exchange (ETDEWEB)

A heat transfer (condenser) of a domestic freezer was tested in a vertical channel in order to study the influence of the chimney effect in the optimization of the heat transfer coefficient. The variation of the opening of the channel, position and the heating power of the heat exchanger in the heat transfer coefficient was considered. The influence of the surface emissivity on the heat transfer by thermal radiation was studied with the heat exchanger testes without paint and with black paint. The air velocity entering the channel was measured with a hot wire anemometer. In order to evaluate the chimney effect, the heat exchanger was testes in a open ambient. This situation simulates its operational conditions when installed on the freezer system. The variables collected in the experimental procedures was gathered in the form of dimensionless parameters as Nusselt, Rayleigh, Grashof and Prandtl numbers, and dimensional ...

1997-07-01

300

Adaptation of a cubic smoothing spline algortihm for multi-channel data stitching at the National Ignition Facility  

Energy Technology Data Exchange (ETDEWEB)

Some diagnostics at the National Ignition Facility (NIF), including the Gamma Reaction History (GRH) diagnostic, require multiple channels of data to achieve the required dynamic range. These channels need to be stitched together into a single time series, and they may have non-uniform and redundant time samples. We chose to apply the popular cubic smoothing spline technique to our stitching problem because we needed a general non-parametric method. We adapted one of the algorithms in the literature, by Hutchinson and deHoog, to our needs. The modified algorithm and the resulting code perform a cubic smoothing spline fit to multiple data channels with redundant time samples and missing data points. The data channels can have different, time-varying, zero-mean white noise characteristics. The method we employ automatically determines an optimal smoothing level by minimizing the Generalized Cross ...

2010-12-28

301

Evolution of health information management and information technology in emergency medicine.  

Science.gov (United States)

The implementation of information technology will continue to have important effects on the practice of emergency medicine. Patient registration and tracking systems, telemedicine electronic order entry systems, and the advent of electronic health records are some examples of applications that influence patient care in emergency departments. We review the literature regarding information technology advances in emergency medicine and outline the important role that emergency physicians play in developing and implementing a national health information technology strategy. PMID:16712540

2006-06-01

302

Experimental study on heat transfer augmentation for high heat flux removal in rib-roughened narrow channels  

International Nuclear Information System (INIS)

Frictional pressure drop and heat transfer performance in a very narrow rectangular channel having one-sided constant heat flux and repeated-ribs were studied experimentally for turbulent water flows. Their empirical correlations were derived for designing target cooling channels to remove high heat flux generated at target plates in a high-intensity proton accelerator system. The rib pitch-to-height ratios (p/k) were 10 and 20 while holding the rib height constant at 0.2 mm, the Reynolds number (Re) from 2,400 to 98,500 under different channel heights (H) of 1.2 mm and 3.2 mm, the rib height-to-channel equivalent diameter ratio (k/D_e) of 0.088 and 0.036, respectively. The results show that the rib-roughened surface augments heat transfer by about 2-2.5 times compared with the smooth surface at the expense of around 2.5 times higher frictional pressure drop under a range of Re=8,000-to-30,000 at ...

1998-09-01

303

Boiling heat transfer in compact heat exchangers  

Energy Technology Data Exchange (ETDEWEB)

Small circular and noncircular channels are representative of flow passages in compact evaporators and condensers. This paper describes results of an experimental study on heat transfer to the flow boiling of refrigerant- 12 in a small circular tube of diameter = 2.46 mm. The objective of the study was to assess the effect of channel size on the heat transfer coefficient and to obtain additional insights relative to the heat transfer mechanisms. The flow channel was made of brass and had an overall length of 0.9 m. The channel wall was electrically heated, and temperatures were measured on the channel wall and in the bulk fluid stream. Voltage taps were located at the same axial locations as the stream thermocouples to allow testing over an exit quality range of 0.21 to 0.94 and a large range of mass flux (63 to 832 kg/m{sup 2}s) and heat flux (2.5 to 59 kW/m{sup 2}). Saturation ...

1994-12-31

304

Turbulent flow in a channel with transverse rib heat transfer augmentation  

Science.gov (United States)

Turbulent flow in a 2D channel with repeated rectangular rib roughness was numerically simulated using a low Reynolds number form of the k-epsilon turbulence model. Friction factors and average Stanton numbers were calculated for various pitch to rib height ratios and bulk Reynolds numbers. Comparisons with experiment were generally adequate, with the predictions of friction superior to those for heat transfer. The effect of variable properties for channel flow was investigated, and the results showed a greater effect for friction than for heat transfer. Comparison with experiment yielded no clear conclusions. The turbulence model was also validated for a related problem, that of flow downstream of an abrupt pipe expansion.

1993-04-01

305

Synchrotron radiation from electron beams in plasma-focusing channels.  

Science.gov (United States)

Spontaneous radiation emitted from relativistic electrons undergoing betatron motion in a plasma-focusing channel is analyzed, and applications to plasma wake-field accelerator experiments and to the ion-channel laser (ICL) are discussed. Important similarities and differences between a free electron laser (FEL) and an ICL are delineated. It is shown that the frequency of spontaneous radiation is a strong function of the betatron strength parameter a(beta), which plays a role similar to that of the wiggler strength parameter in a conventional FEL. For a(beta) > or approximately 1, radiation is emitted in numerous harmonics. Furthermore, a(beta) is proportional to the amplitude of the betatron orbit, which varies for every electron in the beam. The radiation spectrum emitted from an electron beam is calculated by averaging the single-electron spectrum over the electron distribution. This leads to a frequency broadening of the radiation ...

2002-05-20

306

Study of the $pp \\to np\\pi^+$ reaction at 1.25 GeV with HADES  

CERN Document Server

In pp collisions at 1.25 GeV kinetic energy, the HADES collaboration aimed at investigating the di-electron production related to $\\Delta$ (1232) Dalitz decay ($\\Delta^+ \\to pe^+e^-$). In order to constrain the models predicting the cross section and the production mechanisms of $\\Delta$ resonance, the hadronic channels have been measured and studied in parallel to the leptonic channels. The analyses of $pp\\to np\\pi^+$ and $pp\\to pp\\pi^0$ channels and the comparison to simulations are presented in this contribution, in particular the angular distributions being sensitive to $\\Delta$ production and decay. The accurate acceptance corrections have been performed as well, which could be tested in all the phase space region thanks to the high statistic data. These analyses result in an overall agreement with the one-$\\pi$ exchange model and previous data.

2009-01-01

307

Silicon oxide conductivity of hydrogen ion implanted polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The influence of hydrogen ion implantation into the channel polysilicon of polysilicon thin film transistors on gate oxide conductivity has been investigated. Data for effective tunnelling barriers at the gate oxide/channel polysilicon interface are presented. A value of 1.2eV for samples with boron doped channel polysilicon is calculated. For hydrogenated boron doped samples tunnelling barriers higher than 2.1 eV are obtained. The tunnelling barriers for phosphorus doped samples are impurity concentration dependent and decrease with increasing phosphorus concentration in the range 3 x 10{sup 17} to 3 x 10{sup 19} cm{sup -3}. (Author).

1996-10-01

308

Silicon oxide conductivity of hydrogen ion implanted polysilicon thin film transistors  

International Nuclear Information System (INIS)

The influence of hydrogen ion implantation into the channel polysilicon of polysilicon thin film transistors on gate oxide conductivity has been investigated. Data for effective tunnelling barriers at the gate oxide/channel polysilicon interface are presented. A value of 1.2eV for samples with boron doped channel polysilicon is calculated. For hydrogenated boron doped samples tunnelling barriers higher than 2.1 eV are obtained. The tunnelling barriers for phosphorus doped samples are impurity concentration dependent and decrease with increasing phosphorus concentration in the range 3 x 10"1"7 to 3 x 10"1"9 cm"-"3. (Author).

309

Sedimentation of the Enan suite of the lower to middle Jurassic and coal reserves of the southeastern margin of the Ordos basin (China)  

Energy Technology Data Exchange (ETDEWEB)

The studied coal bearing series has a parallel origin. The following facial complexes are isolated in its composition: lakes free of vegetation without coal interlayers; overgrown lakes of their margins which are poor in coals; swampy lakes, whose peat beds formed coal layers of shallow or moderate depth; channel sediments without coal layers and swamps from between channel spaces which created thick coal strata of high quality for which, however, a strong changeability in thickness is intrinsic. The coal strata are normally split towards the central parts of the lake basins and river channels. The coal presence of the suite is reduced along the section which is associated with the replacement of the lake swamp conditions of sedimentation by lake river conditions. A paleotectonic analysis established that the distribution of the zones richest in coal was controlled by consedimentational structural elements.

1983-01-01

310

Quantum coherence in ion channels: resonances, transport and verification  

Energy Technology Data Exchange (ETDEWEB)

Recently it was demonstrated that long-lived quantum coherence exists during excitation energy transport in photosynthesis. It is a valid question up to which length, time and mass scales quantum coherence may extend, how one may detect this coherence and what, if any, role it plays in the dynamics of the system. Here we suggest that the selectivity filter of ion channels may exhibit quantum coherence, which might be relevant for the process of ion selectivity and conduction. We show that quantum resonances could provide an alternative approach to ultrafast two-dimensional (2D) spectroscopy to probe these quantum coherences. We demonstrate that the emergence of resonances in the conduction of ion channels that are modulated periodically by time-dependent external electric fields can serve as signatures of quantum coherence in such a system. Assessments of experimental feasibility and specific paths towards the experimental realization of such ...

2010-08-15

311

Perceived service quality and self-concept influences on consumer attitude and purchase process: A comparison between physical and internet channels  

British Library Electronic Table of Contents (United Kingdom)

This study aimed to explore the impact of perceived service quality and self-concept on consumer attitude and purchase process using channel type (physical and Internet) as a segmentation variable. From the perspective of consumer behaviour, this study attempted to estimate a relational model and perform an empirical validation using female cosmetics and skincare products as an example. It was discovered that the influence of perceived service quality and self-concept on consumer attitude, purchase intention and behaviour, satisfaction, and loyalty varied with channel type. The analysis result revealed that physical stores presented higher levels of agreement with all research perspectives than Internet stores. However, only two relational paths have a higher influencing effect in physical...

2011-01-01

312

Observation of 77 K staircase I-V characteristics in 2DEG's irradiated by a focused ion beam  

International Nuclear Information System (INIS)

Staircase current-voltage (I-V) characteristics, observed at 77 K in narrow 2DEG channels irradiated by a single line scan of a focused ion beam (FIB), is reported in detail. These staircases are interpreted as evidence of single electron tunneling through a naturally occurring specific Coulomb island in the random potential fluctuations created by FIB damage. Clear comparison is made between the I-V's taken from wide channels and those from narrow channels. Based on orthodox calculations of the I-V characteristics, it is shown that highly asymmetric tunnel junctions are needed to explain our data. This is consistent with the random nature of the potential landscape in the FIB damaged region. (author).

313

Mixed convection in a horizontal rectangular channel - Experimental and numerical velocity distributions  

Science.gov (United States)

Mixed convection in a rectangular channel (width/height = 2) with bottom-heated and top-cooled sections is studied by laser Doppler anemometry in nitrogen at Ra = 22,200 and Re = 18.75, 36, and 54. At the lower Re values, symmetry breaking is observed in steady but spatially oscillating flows that prevail over a certain distance from the leading edge of the differentially heated section. Further downstream, unsteady flows are found even for Re = 18.75. Numerical models are used to investigate the effects of adiabatic, conducting (with a conductive-convective heat transfer coefficient), and perfectly conducting side walls; channel tilts and Prandtl number dependence. Good agreement between calculations and experiment is obtained for longitudinal convective roll velocities. The transverse velocities are found to be independent of Re.

1992-06-01

314

Mass transfer in horizontal flow channels with thermal gradients  

Energy Technology Data Exchange (ETDEWEB)

Mass transfer to a wall of a horizontal rectangular channel reactor was investigated by the limiting current technique for Reynolds numbers ranging from 200 to 32000. Overall mass transfer coefficients at various mass transfer surface angles were obtained while the reactor was operated under isothermal and non-isothermal conditions. Dimensionless correlations were developed for isothermal flows from 25 to 55{sup o}C and for non-isothermal flows with applied temperature differences up to 30{sup o}C. In the laminar flow range natural convection dominated, but under turbulent conditions combined natural and forced convection prevailed. Mass transfer was approximately doubled under optimum selection of channel surface rotation, temperature gradient and flow rate. (author)

1997-12-15

315

Mass transfer in horizontal flow channels with thermal gradients  

International Nuclear Information System (INIS)

Mass transfer to a wall of a horizontal rectangular channel reactor was investigated by the limiting current technique for Reynolds numbers ranging from 200 to 32000. Overall mass transfer coefficients at various mass transfer surface angles were obtained while the reactor was operated under isothermal and non-isothermal conditions. Dimensionless correlations were developed for isothermal flows from 25 to 55"oC and for non-isothermal flows with applied temperature differences up to 30"oC. In the laminar flow range natural convection dominated, but under turbulent conditions combined natural and forced convection prevailed. Mass transfer was approximately doubled under optimum selection of channel surface rotation, temperature gradient and flow rate. (author)

1997-12-01

316

Internal heat transfer augmentation in a channel using an alternate set of porous cavity-block obstacles  

Energy Technology Data Exchange (ETDEWEB)

A numerical investigation for forced convection in a constant-temperature parallel plate channel with porous cavity and block alternately emplaced on the bottom plate is presented in this work. The Brinkman-Forchheimer-extended Darcy model, which accounts for the effects of impermeable boundary and inertia, is used to characterize the flow field inside the porous region. Solutions of the coupled governing equations are carried out through the stream function-vorticity analysis. The characteristics of fluid flow and forced convection heat transfer have been obtained by the examinations of various governing parameters, such as the Reynolds number, Darcy number, inertial parameter, Prandtl number, and two geometric parameters. Several interesting phenomena such as the heat transfer augmentation in the channel were presented and discussed. The results of this investigation indicate that the size of recirculation caused by porous block will have a ...

1994-05-01

317

Intermediate-conductance calcium-activated potassium channels participate in neurovascular coupling  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Controlling vascular tone involves K+ efflux through endothelial cell small- and intermediate-conductance calcium-activated potassium channels (KCa2.3 and KCa3.1, respectively). We investigated the expression of these channels in astrocytes and the possibility that, by a similar mechanism, they might contribute to neurovascular coupling. EXPERIMENTAL APPROACH Transgenic mice expressing enhanced green fluorescent protein (eGFP) in astrocytes were used to assess KCa2.3 and KCa3.1 expression by immunohistochemistry and RT-PCR. KCa currents in eGFP-positive astrocytes were determined in situ using whole-cell patch clamp electrophysiology. The contribution of KCa3.1 to neurovascular coupling was investigated in pharmacological experiments using electrical field stimulatio...

2011-01-01

318

Inhibition of the heterotetrameric K++ channel KCNQ1/KCNE1 by the AMP-activated protein kinase  

British Library Electronic Table of Contents (United Kingdom)

Abstract The heterotetrameric K++-channel KCNQ1/KCNE1 is expressed in heart, skeletal muscle, liver and several epithelia including the renal proximal tubule. In the heart, it contributes to the repolarization of cardiomyocytes. The repolarization is impaired in ischemia. Ischemia stimulates the AMP-activated protein kinase (AMPK), a serine/threonine kinase, sensing energy depletion and stimulating several cellular mechanisms to enhance energy production and to limit energy utilization. AMPK has previously been shown to downregulate the epithelial Na++ channel ENaC, an effect mediated by the ubiquitin ligase Nedd4-2. The present study explored whether AMPK regulates KCNQ1/KCNE1. To this end, cRNA encoding KCNQ1/KCNE1 was injected into Xenopus oocytes with and without additional injection o...

2011-01-01

319

Influence of gully erosion control on amphibian and reptile communities within riparian zones of channelized streams  

British Library Electronic Table of Contents (United Kingdom)

Riparian zones of streams in northwestern Mississippi have been impacted by agriculture, channelization, channel incision, and gully erosion. Riparian gully formation has resulted in the fragmentation of remnant riparian zones within agricultural watersheds. One widely used conservation practice for controlling gully erosion is the installation of drop pipes. This practice involves placing earthen dams across eroding gullies and embedding a metal standpipe within the dam to convey water from the field to stream level. Installation of this structure halts gully erosion and incidentally replaces eroding gullies with riparian habitats. Previous research evaluating gully erosion control structures have not considered the ecological impacts of these conservation practices on amphibian and repti...

2009-01-01

320

Fermi liquid and non-Fermi liquid in M-channel N fold degenerate anderson lattice  

Energy Technology Data Exchange (ETDEWEB)

We investigate Fermi liquid in the single-channel U-infinite N fold degenerate Anderson lattice with use of the expansion from the large limit of the spin-orbital degeneracy N. By collecting all diagrams up to O(N{sup -2}) of the imaginary part of the self-energy of the conduction electrons, the sum of those is shown to be given by a form proportional to {omega}{sup 2} + {pi}{sup 2}T{sup 2} up to O(N{sup -2}) in the single-channel model. On the other hand, the imaginary part of the self-energy of O(N{sup -1}) in the multichannel model has more singular frequency-/temperature-dependence, so the system is regarded as non-Fermi liquid. (author)

1999-02-28

321

Fast leak in channel H9  

International Nuclear Information System (INIS)

The loss of seal of the H9 channel in vacuum, freeing the entire cross section of the front part, leads to a fast leak that progresses rapidly. The effect of depressurizing the reflector can leads to shutdown of the shutdown rod pumps. The source changer associated with the channel fills completely before the valve closes. All of the leak water remains contained within the source changer containment. After the valves open, cooling of the fuel element is handled by natural convection, requiring a reversal of the flow between the plates. This changeover, which takes place at a relatively low pressure level, could lead to local boiling in the fuel element. Consequently, irreversible transformations cannot be excluded as possibilities for the fuel element and even for the control rod. Subsequently, the can is refilled with heavy water with establishment of the usual pressure levels.

322

Experimental study of convective self-oscillations near the lateral surface of a bubble in a plane rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Experimental investigations have been performed to study solutal convection around an air bubble squeezed between the walls of a horizontal rectangular channel, filled by an aqueous solution of surfactant with vertically stratified concentration. A convective motion in the fluid develops due to the solutocapillary Marangoni forces at the bubble lateral free surface. The structure and evolution of the convective flow and the surfactant concentration fields in the channel have been investigated using interferometric technique. The tests revealed the development of self-oscillatory modes near the bubble surface, related to the interaction between solutocapillary and solutogravitational motion mechanisms. The time dependences of the oscillations period are analyzed in relation to the average c...

2008-01-01

323

Effect of the induced magnetic field on peristaltic flow of a couple stress fluid  

Science.gov (United States)

We have analyzed the MHD flow of a conducting couple stress fluid in a slit channel with rhythmically contracting walls. In this analysis we are taking into account the induced magnetic field. Analytical expressions for the stream function, the magnetic force function, the axial pressure gradient, the axial induced magnetic field and the distribution of the current density across the channel are obtained using long wavelength approximation. The results for the pressure rise, the frictional force per wave length, the axial induced magnetic field and distribution of the current density across the channel have been computed numerically and the results were studied for various values of the physical parameters of interest, such as the couple stress parameter ?, the Hartmann number M, the magnetic Reynolds number R and the time averaged mean flow rate ?. Contour plots for the stream and magnetic force functions are obtained and ...

2008-06-01

324

Development and validation of a CATHENA fuel channel model for a post-blowdown analysis of the high temperature thermal-chemical experiment CS28-1  

British Library Electronic Table of Contents (United Kingdom)

To form a licensing basis for a new methodology for a fuel channel safety analysis code for CANDU-6 nuclear reactor, a CATHENA model for a post-blowdown fuel channel analysis has been developed, and tested for a high temperature thermal-chemical experiment CS28-1 [Lei, Q.M., 1993. Post-test analysis of the 28-element high-temperature thermal-chemical experiment CS28-1. In: 4th International Conference on Simulation Methods in Nuclear Engineering, Montreal, PQ, 1993]. Pursuant to the objective of this investigation, the current study has focused on understanding the involved phenomena, their interrelations, and how to maintain a good accuracy of the temperature and H2 generation rate prediction without losing the important physics of the involved phenomena. The transient simulation results ...

2009-01-01

325

Competition between multiphoton fragmentation channels in H sub 2 and HD induced by intermediate states  

Energy Technology Data Exchange (ETDEWEB)

The proton and deuteron spectra following resonant multiphoton ionization of H{sub 2} and HD at 193 nm through the {ital E},{ital F} state have been studied at power densities of 10{sup 10} W/cm{sup 2}. Our results show that the intermediate state induces competition between 3(2+1)-photon ionization, dissociation, and dissociative ionization channels. We find that the competition depends on the specific vibrational and rotational levels excited in the intermediate state. At the same time, the mere presence of this bound intermediate state renders these three-photon fragmentation channels so efficient that higher-order fragmentation processes, such as Coulomb explosions requiring many more photons, are not observed.

1991-04-01

326

Comparison of the channel coupling array and CRC methods for a realistic nuclear transfer-reaction model  

International Nuclear Information System (INIS)

Using a realistic three-body model, angular distributions for the "1"6O(d,p)"1"7O(1/2"+) reaction, based on the channel coupling array (CCA) theory and various forms of the coupled reaction channel (CRC) method are compared. Despite the different forms and theoretical foundations of these methods, they yield similar angular distributions, within the bound state approximations used herein. The expected breaking of time reversal inveriance in the approximated CCA theory is quite small over most of the angular range. Of all the methods used, coupling effects in the forward directions are largest for the post form of the CRC, indicating that it is the least reliable of the CRC forms for fitting data. (Auth.).

327

Application of chaos theory in identification of two-phase flow patterns and transitions in a small, horizontal, rectangular channel  

Energy Technology Data Exchange (ETDEWEB)

Various measurement tools that are used in chaos theory were applied to analyze two-phase pressure signals with the objective of identifying and interpreting flow pattern transitions for two-phase flows in a small, horizontal rectangular channel. These measurement tools included power spectral density function, autocorrelation function, pseudo-phase-plane trajectory, Lyapunov exponent,s and fractal dimensions. It was demonstrated that the randomlike pressure fluctuations characteristic of two-phase flow in small rectangular channels are chaotic, and governed by a high-order deterministic system. The correlation dimension is potentially a new approach for identifying certain two-phase flow patterns and transitions.

1996-06-01

328

AWGN Channel Analysis of Terminated LDPC Convolutional Codes  

CERN Document Server

It has previously been shown that ensembles of terminated protograph-based low-density parity-check (LDPC) convolutional codes have a typical minimum distance that grows linearly with block length and that they are capable of achieving capacity approaching iterative decoding thresholds on the binary erasure channel (BEC). In this paper, we review a recent result that the dramatic threshold improvement obtained by terminating LDPC convolutional codes extends to the additive white Gaussian noise (AWGN) channel. Also, using a (3,6)-regular protograph-based LDPC convolutional code ensemble as an example, we perform an asymptotic trapping set analysis of terminated LDPC convolutional code ensembles. In addition to capacity approaching iterative decoding thresholds and linearly growing minimum distance, we find that the smallest non-empty trapping set of a terminated ensemble grows linearly with block length.

2011-01-01

329

A real-time neutron radiography diagnostic of a vertical co-current two-phase flow channel with a hexagonal finned bundle  

International Nuclear Information System (INIS)

A Real-Time Neutron Radiography (RTNR) system is developed to determine two-phase flow parameters for a vertical co-current two-phase flow channel with a hexagonal finned bundle. Image processing techniques are applied to visualize the two-phase flow, and procedures for measuring flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution for this complex geometry are discussed. The results show that the experimental flow regime map agrees well with an existing flow regime model for a hexagonal fined bundle. The hexagonal finned bundle is observed to significantly affect the void fraction, void migration, and void fluctuation along the axial flow channel.

2003-06-01

330

Use of information sources by family physicians: a literature survey.  

UK PubMed Central (United Kingdom)

Analysis of the use of information sources by family physicians is important for both practical and theoretical reasons. First, analysis of the ways in which family physicians handle information may...Full Text Available

1995-01-01

331

Self-Study Digital Library Courseware  

Science.gov (United States)

Tutorial on digital libraries. Site also contains links to other reference materials on digital libraries as well as links to courses on the subject. Keywords: Information Systems - Information Systems Applications, Information Storage and Retrieval, Database Management, multimedia

2001-12-01

332

Scenario Customization for Information Extraction.  

Science.gov (United States)

Information Extraction (IE) is an emerging NLP technology, whose function is to process unstructured, natural language text, to locate specific pieces of information, or facts, in the text, and to use these facts to fill a database. IE systems today are c...

2001-01-01

333

Network information security in a phase III Integrated Academic Information Management System (IAIMS).  

UK PubMed Central (United Kingdom)

The developing Integrated Academic Information System (IAIMS) at Columbia-Presbyterian Medical Center provides data sharing links between two separate corporate entities, namely Columbia University...Full Text Available

1992-01-01

335

Information circulars  

International Nuclear Information System (INIS)

Information circulars are published from time to time under the symbol INFCIRC/... for the purpose of bringing matters of general interest to the attention of all Members of the Agency. The present revision contains INFCIRCs published up to mid-August 1994. A complete numerical list of information circulars is reproduced with their titles in the Annex.

2005-08-01

336

Impact of informed-choice invitations on diabetes screening knowledge, attitude and intentions: an analogue study  

UK PubMed Central (United Kingdom)

BackgroundDespite concerns that facilitating informed choice would decrease diabetes screening uptake, 'informed choice' invitations that increased knowledge did not affect attendance...Full Text Available

337

Impact and User Satisfaction of a Clinical Information Portal Embedded in an Electronic Health Record  

UK PubMed Central (United Kingdom)

In 2008, a clinical information tool was developed and embedded in the electronic health record system of an academic medical center. In 2009, the initial information tool, Clinical-e, was superseded...Full Text Available

338

Hospital information management: the need for clinical leadership.  

UK PubMed Central (United Kingdom)

On 12 July the Audit Commission published For Your Information, a well researched report about information and its management in acute hospitals in Britain, how and why it is failing, and steps that...Full Text Available

1995-07-15

339

Finding Answers: Information Needs of a Multidisciplinary Patient Care Team in an Emergency Department  

UK PubMed Central (United Kingdom)

Emergency Departments (ED) are fast-paced, information-intensive environments where patient care team members must address their information needs quickly and accurately. We conducted a qualitative...Full Text Available

2006-01-01

340

Extracting medical information from narrative patient records: the case of medication-related information  

UK PubMed Central (United Kingdom)

ObjectiveWhile essential for patient care, information related to medication is often written as free text in clinical records and, therefore, difficult to use in computerized systems....Full Text Available

2010-09-01

341

Blowing in the Wind: Unanchored Patient Information Work during Cancer Care  

UK PubMed Central (United Kingdom)

Patients do considerable information work. Technologies that help patients manage health information so they can play active roles in their health-care, such as personal health records, provide...Full Text Available

2010-01-01

342

45 CFR 170.205 - Content exchange standards and implementation specifications for exchanging electronic health...  

Science.gov (United States)

...standards and implementation specifications for exchanging electronic health information. 170.205 Section 170.205 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY...

2010-10-01

343

Section 508 and Electronic Information Technology Accessibility at EPA | US EPA  

Wastenet

...Section 508 and Electronic Information Technology Accessibility at EPA | US EPA Jump to main content. Section 508 and Electronic Information Technology ...Us Search: All EPA Advanced search You are here: EPA Home Section 508 and Electronic Information Technology Accessibility at EPA Welcome to the United ... Section 508 of the Rehabilitation Act mandates that Federal departments and agencies make electronic and information technology (EIT) accessible to individuals ... Achieving compliance with Section 508 is an ongoing process. If you have any problems or questions about accessing information on a particular ...

344

Information processing, computation, and cognition  

British Library Electronic Table of Contents (United Kingdom)

Computation and information processing are among the most fundamental notions in cognitive science. They are also among the most imprecisely discussed. Many cognitive scientists take it for granted that cognition involves computation, information processing, or both ? although others disagree vehemently. Yet different cognitive scientists use ?computation? and ?information processing? to mean different things, sometimes without realizing that they do. In addition, computation and information processing are surrounded by several myths; first and foremost, that they are the same thing. In this paper, we address this unsatisfactory state of affairs by presenting a general and theory-neutral account of computation and information processing. We also apply our framework by analyzing the relatio...

2011-01-01

345

IQARIS : a tool for the intelligent querying, analysis, and retrieval from information systems.  

Energy Technology Data Exchange (ETDEWEB)

Information glut is one of the primary characteristics of the electronic age. Managing such large volumes of information (e.g., keeping track of the types, where they are, their relationships, who controls them, etc.) can be done efficiently with an intelligent, user-oriented information management system. The purpose of this paper is to describe a concept for managing information resources based on an intelligent information technology system developed by the Argonne National Laboratory for managing digital libraries. The Argonne system, Intelligent Query (IQ), enables users to query digital libraries and view the holdings that match the query from different perspectives.

2002-04-26

346

Cells as semantic systems  

British Library Electronic Table of Contents (United Kingdom)

Background: We consider cells as biological systems that process information by means of molecular codes. Many studies analyze cellular information processing exclusively in syntactic terms (e.g., by measuring Shannon entropy of sets of macromolecules), and abstract completely from semantic aspects that are related to the meaning of molecular information. Methods: This mini-review focusses on semantic aspects of molecular information, particularly on codes that organize the semantic dimension of molecular information. First, a general conceptual framework for describing molecular information is proposed. Second, some examples of molecular codes are presented. Third, a mathematical approach that makes the identification of molecular codes in reaction networks possible, is developed. Results...

2011-01-01

347

ADS-Directory Services for Mobile Ad-Hoc Networks Based on an Information Market Model  

CERN Document Server

Ubiquitous computing based on small mobile devices using wireless communication links is becoming very attractive. The computational power and storage capacities provided allow the execution of sophisticated applications. Due to the fact that sharing of information is a central problem for distributed applications, the development of self organizing middleware services providing high level interfaces for information managing is essential. ADS is a directory service for mobile ad-hoc networks dealing with local and nearby information as well as providing access to distant information. The approach discussed throughout this paper is based upon the concept of information markets.

2007-01-01

348

War in the Information Age: A Primer for Cyberspace ...  

Science.gov (United States)

... A Primer for Cyberspace ... 4. TITLE AND SUBTITLE War in the Information Age: A Primer for Cyberspace Operations in 21st Century Warfare 5a. ...

2011-05-15

349

VERSION 2.1 - NASA Blogs  

Science.gov (United States)

Information superiority provides the Joint force a competitive ... Information Grid (GIG) as it matures and fills the needs of the Joint Task Force ... representatives from The Army Secretariat, Headquarters Department of Army ...

350

Untitled Document  

Science.gov (United States)

integrates multiple fisheries information systems to obtain a view of U.S. freshwater fish distribution. Information about NFDI National Framework for Early Detection, Rapid...

2011-06-23

351

The I3I Model; Identifying Cultural Determinants of Information ...  

Science.gov (United States)

... Information behavior in dynamic group work contexts: Interwoven situational awareness, dense social networks and contested collaboration in ...

2009-06-01

352

Quality and availability of consumer information on heart failure in Australia  

UK PubMed Central (United Kingdom)

BackgroundProvision of consumer information and patient education are considered an essential part of chronic disease management programmes developed for patients with heart failure....Full Text Available

353

Monthly Newsletter October 2003 NASA OH ... - OH Home - NASA  

Science.gov (United States)

with health information management technology Agency-wide. In parallel to the task force appointment, a request for information ...

354

Joint Battlespace Infosphere (JBI): Information Management in ...  

Science.gov (United States)

... In this manner, a JBI-enabled COI would have the full suite of JBI information management capabilities, but would still be based on and have full ...

2006-05-01

355

Information Technology - NASA Science  

Science.gov (United States)

Mar 15, 2011 ... Information Technology. NCCS Discover Supercomputer. Science mission data collection, analysis and simulations pose unprecedented computer ...

356

Health Information for Travelers to South Africa - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) South Africa Regions Vaccinations News & Announcements Travel...

2011-08-28

357

Health Information for Travelers to Somalia - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Somalia Regions Vaccinations News & Announcements Travel...

2011-08-28

358

Health Information for Travelers to Saudi Arabia - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Saudi Arabia Regions Vaccinations News & Announcements Travel...

2011-08-28

359

Health Information for Travelers to Rwanda - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Rwanda Regions Vaccinations News & Announcements Travel...

2011-08-28

360

Health Information for Travelers to Mozambique - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Mozambique Regions Vaccinations News & Announcements Travel...

2011-08-28

361

Health Information for Travelers to Malawi - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Malawi Regions Vaccinations News & Announcements Travel...

2011-08-28

362

Health Information for Travelers to Kenya - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Kenya Regions Vaccinations News & Announcements Travel Notices...

2011-08-28

363

Health Information for Travelers to Gabon - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Gabon Regions Vaccinations News & Announcements Travel Notices...

2011-08-28

364

Health Information for Travelers to Ethiopia - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Ethiopia Regions Vaccinations News & Announcements Travel...

2011-08-28

365

Health Information for Travelers to Eritrea - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Eritrea Regions Vaccinations News & Announcements Travel...

2011-08-28

366

Health Information for Travelers to Equatorial Guinea - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Equatorial Guinea Regions Vaccinations News & Announcements...

2011-08-28

367

Health Information for Travelers to Djibouti - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Djibouti Regions Vaccinations News & Announcements Travel...

2011-08-28

368

Health Information for Travelers to Democratic Republic of the...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Democratic Republic of the Congo Regions Vaccinations News &...

2011-08-28

369

Health Information for Travelers to Antarctica - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Antarctica Regions Vaccinations News & Announcements Travel...

2011-08-28

370

Health Information Technology and Physician Career Satisfaction  

UK PubMed Central (United Kingdom)

PurposeHealth information technology (HIT) and physician career satisfaction are associated with higher-quality medical care. However, the link between HIT and physician...Full Text Available

371

Geographic information systems: their use in environmental epidemiologic research.  

UK PubMed Central (United Kingdom)

Advances in geographic information system (GIS) technology, developed by geographers, provide new opportunities for environmental epidemiologists to study associations between environmental exposures...Full Text Available

1997-06-01

372

Flood Plain Information. Kenai River, Phase I. Kenai ...  

Science.gov (United States)

... Accession Number : ADA067692. Title : Flood Plain Information. Kenai River, Phase I. Kenai Peninsula Borough, Alaska. ...

1973-06-01

373

Conference on Information Technology (2nd)/Special Session ...  

Science.gov (United States)

... Topics includes: Formal methods in information engineering, Electronic documents and digital libraries Autonomous robots in embeded systems ...

2004-08-23

374

Center for Intelligent Information Retrieval  

Science.gov (United States)

evaluation, novelty detection, resource discovery, interfaces and visualization, digital libraries, computational social science, and cross-lingual information retrieval. The CIIR...

2011-08-31

375

Browsing for Information on the Web and in the File System  

Science.gov (United States)

... SIGCHI Bull., 27(3), (1995), 39-43. 3. Bruce, H., Jones, W., Dumais, S. Information behavior that keeps found things found. ...

2007-02-23

376

Background information on the high energy physics program and the proposed Stanford linear electron accelerator project  

CERN Document Server

Background information on the high energy physics program and the proposed Stanford linear electron accelerator project

1961-01-01

377

A New Model for the Organizational Structure of Medical Record Departments in Hospitals in Iran  

UK PubMed Central (United Kingdom)

The organizational structure of medical record departments in Iran is not appropriate for the efficient management of healthcare information. In addition, there is no strong information management division...Full Text Available

378

Water management studies in PEM fuel cells, Part I: Fuel cell design and in situ water distributions  

Energy Technology Data Exchange (ETDEWEB)

A proton exchange membrane fuel cell (PEMFC) must maintain a balance between the hydration level required for efficient proton transfer and excess liquid water that can impede the flow of gases to the electrodes where the reactions take place. Therefore, it is critically important to understand the two-phase flow of liquid water combined with either the hydrogen (anode) or air (cathode) streams. In this paper, we describe the design of an in situ test apparatus that enables investigation of two-phase channel flow within PEMFCs, including the flow of water from the porous gas diffusion layer (GDL) into the channel gas flows; the flow of water within the bipolar plate channels themselves; and the dynamics of flow through multiple channels connected to common manifolds which maintain a uniform pressure differential across all possible flow paths. These two-phase flow effects have been studied at relatively ...

2009-05-15

379

Verification of coolant flow distribution in 540 MWe Indian PHWR during commissioning  

International Nuclear Information System (INIS)

The pressurized Heavy Water Reactor (PHWR) consists of horizontal calandria vessel containing a large number of pressure tubes (fuel channels) connected to the reactor inlet and outlet headers by individual feeders. Coolant flow distribution among the pressure tubes play a vital role in extraction of thermal power. For these reactors one of the design objectives is to achieve uniform coolant outlet temperatures by providing coolant flows according to the channel power. This is achieved by the design process known as feeder sizing. This basically consists of accounting for the individual channel power and centre line geometry of individual feeder and iteratively adjusting the feeder hydraulic resistances within the design constraints such as limiting flow velocities, channel flows. Recently, the first unit of 540 MWe i.e Tarapur Atomic Power Project (unit 4) has been commissioned. This paper discusses ...

2006-11-13

380

Velocity measurement of wake behind flat plate simulating BWR fuel spacer  

International Nuclear Information System (INIS)

Velocity field behind a flat plate, placed near the wall in a narrow channel as a simulant of a BWR fuel spacer, was measured by using a hot wire anemometer. It was found that not only the positions where the dead water region behind flat plate disappeared but also the locations where the velocity relaxation completed were almost independent of the width of the clearance, although the local average velocity and velocity fluctuation immediately downstream the flat plate were affected by the difference in the clearance. The transverse flow diversions in the channel cross section were evaluated from the shape of the average velocity profile. The decrease of local flow rate near the channel wall, which may causes the drift flow behind a flat plate, was encouraged as the drag of clearance increased. Attempts have been made to measure spanwise velocity in the narrow channel. A spanwise velocity that occurred ...

2004-10-04

381

Variability In Motor Learning: Relocating, Channeling and Reducing Noise  

UK PubMed Central (United Kingdom)

Variability in motor performance decreases with practice but is never entirely eliminated, due in part to inherent motor noise. The present study develops a method that quantifies how performers...Full Text Available

2009-02-01

382

Thermosensitive TRP channel pore turret is part of the temperature activation pathway  

UK PubMed Central (United Kingdom)

Temperature sensing is crucial for homeotherms, including human beings, to maintain a stable body core temperature and respond to the ambient environment. A group of exquisitely temperature-sensitive...Full Text Available

2010-04-13

383

The use of quartz patch pipettes for low noise single channel recording.  

UK PubMed Central (United Kingdom)

Quartz has a dissipation factor of approximately 10(-4), which is an order of magnitude less than that of the best glasses previously used to fabricate patch pipettes; it's dielectric constant of 3.8...Full Text Available

1993-10-01

384

The role of calcium ions and calcium channel entry blockers in experimental ischemia-reperfusion-induced liver injury.  

UK PubMed Central (United Kingdom)

Verapamil administered before treatment, but not after treatment, had a beneficial effect on a 90-minute warm ischemia-reperfusion rat liver injury model. The possible activation of proteases converting...Full Text Available

1991-02-01

385

The L-type calcium channel inhibitor diltiazem prevents cardiomyopathy in a mouse model  

UK PubMed Central (United Kingdom)

Dominant mutations in sarcomere protein genes cause hypertrophic cardiomyopathy, an inherited human disorder with increased ventricular wall thickness, myocyte hypertrophy, and disarray. To understand...Full Text Available

2002-04-15

386

The Dystrophin Complex Controls BK Channel Localization and Muscle Activity in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

Genetic defects in the dystrophin-associated protein complex (DAPC) are responsible for a variety of pathological conditions including muscular dystrophy, cardiomyopathy, and vasospasm. Conserved DAPC...Full Text Available

2009-12-01

387

Tarantula Huwentoxin-IV Inhibits Neuronal Sodium Channels by Binding to Receptor Site 4 and Trapping the Domain II Voltage Sensor in the Closed Configuration*S?  

UK PubMed Central (United Kingdom)

Peptide toxins with high affinity, divergent pharmacological functions, and isoform-specific selectivity are powerful tools for investigating the structure-function relationships of voltage-gated...Full Text Available

2008-10-03

388

Role of surface degrees of freedom in grazing heavy ion collisions  

Energy Technology Data Exchange (ETDEWEB)

A survey is given of the influence of surface deformations on heavy ion reactions. Emphasis is put on the effect of zeropoint fluctuations in the entrance channel and on the effect on grazing collisions in terms of an imaginary part of the scattering potential.

1983-11-14

389

Role of surface degrees of freedom in grazing heavy ion collisions  

International Nuclear Information System (INIS)

A survey is given of the influence of surface deformations on heavy ion reactions. Emphasis is put on the effect of zeropoint fluctuations in the entrance channel and on the effect on grazing collisions in terms of an imaginary part of the scattering potential. (orig.).

390

Research in heavy-ion nuclear physics. [Dept. of Physics and Astronomy, The Univ. of Kansas, Lawrence, Kansas  

Energy Technology Data Exchange (ETDEWEB)

Attention was focused on the fission process in light nuclear systems. A model calculation based on the transition-state model of nuclear fission was applied to [sup 47]V fission as populated through multiple entrance channels and to fusion-fission cross sections for production of [sup 28]Al through three different entrance channels. Angular distributions are shown for different mass channels of the [sup 29]Si+[sup 27]Al reaction at E[sub lab] = 125 MeV. Pronounced structure is seen in the symmetric and near-symmetric fission channels from the [sup 24]Mg+[sup 24]Mg reaction; cross sections for binary fragment emission are shown for E[sub lab] = 90 MeV. A large Bragg-curve detector was used in this experiment. Ways to optimize detector response were studied; in addition, the Bragg detector was instrumented with an internal position-sensitive multiwire proportional counter.

1992-01-01

391

Research in heavy-ion nuclear physics. Annual progress report, May 1, 1992--April 30, 1993  

Energy Technology Data Exchange (ETDEWEB)

Attention was focused on the fission process in light nuclear systems. A model calculation based on the transition-state model of nuclear fission was applied to {sup 47}V fission as populated through multiple entrance channels and to fusion-fission cross sections for production of {sup 28}Al through three different entrance channels. Angular distributions are shown for different mass channels of the {sup 29}Si+{sup 27}Al reaction at E{sub lab} = 125 MeV. Pronounced structure is seen in the symmetric and near-symmetric fission channels from the {sup 24}Mg+{sup 24}Mg reaction; cross sections for binary fragment emission are shown for E{sub lab} = 90 MeV. A large Bragg-curve detector was used in this experiment. Ways to optimize detector response were studied; in addition, the Bragg detector was instrumented with an internal position-sensitive multiwire proportional counter.

1992-01-01

392

Reduced thermal sensitivity and Nav1.8 and TRPV1 channel expression in sensory neurons of aged mice  

UK PubMed Central (United Kingdom)

Sensory neurons in aging mammals undergo changes in anatomy, physiology and gene expression that correlate with reduced sensory perception. In this study we compared young and aged mice to identify...Full Text Available

2006-06-01

393

Recent uses of robotics for remote inspection and maintenance  

International Nuclear Information System (INIS)

This paper documents some of the recent uses of robotics for inspection and maintenance activities in Ontario Hydro's nuclear power plants in areas other than fuel channels and steam generators. 7 figs.

1992-11-22

394

Real-Time Assessment of Cardiac Perfusion, Coronary Angiography, and Acute Intravascular Thrombi Using Dual-Channel Near-Infrared Fluorescence Imaging  

UK PubMed Central (United Kingdom)

ObjectivesWe have developed an image-guided surgery system based on invisible near-infrared (NIR) fluorescent light. Presently, the only clinically-available NIR...Full Text Available

2009-07-01

395

Potential description of cluster channel of lithium nuclei  

International Nuclear Information System (INIS)

The new Gaussian potentials and interactions with forbidden states consistent with the phase scattering at low energies were obtained. Cross sections, resonance level spectra and some characteristics of bound states of lithium nuclei are calculated with these potentials.

396

Potassium channels as a potential therapeutic target for trigeminal neuropathic and inflammatory pain  

UK PubMed Central (United Kingdom)

Previous studies in several different trigeminal nerve injury/inflammation models indicated that the hyperexcitability of primary afferent neurons contributes to the pain pathway underlying mechanical...Full Text Available

397

PKC expression is regulated by dietary K intake and mediates internalization of SK channels in the CCD  

UK PubMed Central (United Kingdom)

We have used Western blot analysis and immunocytochemistry to determine the effect of dietary K intake on the expression of protein kinase C (PKC) isoforms in the kidney. Western blot has demonstrated...Full Text Available

2004-06-01

398

Oxidation of an engineered pore cysteine locks a voltage-gated K+ channel in a nonconducting state.  

UK PubMed Central (United Kingdom)

We report the use of cysteine-substituted mutants in conjunction with in situ oxidation to determine the physical proximity of a pair of engineered cysteines in the pore region of the voltage-gated...Full Text Available

1996-12-01

399

Novel Analogs and Stereoisomers of the Marine Toxin Neodysiherbaine with Specificity for Kainate Receptors  

UK PubMed Central (United Kingdom)

Antagonists for kainate receptors (KARs), a family of glutamate-gated ion channels, are efficacious in a number of animal models of neuropathologies, including epilepsy, migraine pain, and anxiety....Full Text Available

2008-02-01

400

Macroscopic consequences of calcium signaling in microdomains: A first passage time approach  

CERN Document Server

Calcium (Ca) plays an important role in regulating various cellular processes. In a variety of cell types, Ca signaling occurs within microdomains where channels deliver localized pulses of Ca which activate a nearby collection of Ca-sensitive receptors. The small number of channels involved ensures that the signaling process is stochastic. The aggregate response of several thousand of these microdomains yields a whole-cell response which dictates the cell behavior. Here, we study analytically the statistical properties of a population of these microdomains in response to a trigger signal. We apply these results to understand the relationship between Ca influx and Ca release in cardiac cells. In this context, we use a first passage time approach to show analytically how Ca release in the whole cell depends on the single channel kinetics of Ca channels and the properties of microdomains. Using these ...

2007-01-01

401

K+ Channels Are Responsible for an Inwardly Rectifying Current in the Plasma Membrane of Mesophyll Protoplasts of Avena sativa 12  

UK PubMed Central (United Kingdom)

In whole-cell recording, the conductance of the plasma membrane of protoplasts isolated from mesophyll cells of leaves of oat (Avena sativa) was greater for inward than outward current....Full Text Available

1992-03-01

402

Interaction of Heparins and Dextran Sulfates with a Mesoscopic Protein Nanopore  

UK PubMed Central (United Kingdom)

AbstractA mechanism of how polyanions influence the channel formed by Staphylococcus aureus α-hemolysin is described. We demonstrate that the probability of several...Full Text Available

2009-12-02

403

Initial Development and Characterization of PLGA Nanospheres Containing Ropivacaine  

UK PubMed Central (United Kingdom)

Local anesthetics are able to induce pain relief by binding to the sodium channels of excitable membranes, blocking the influx of sodium ions and the propagation of the nervous impulse. Ropivacaine...Full Text Available

2007-12-01

404

Heat-transfer analysis of the plum brook reactor - NASA Technical ...  

Science.gov (United States)

average bulk water temper ature rise, OF bulk water temperature at elevation z, OF bulk water temperature in channels 0 and 1, O F film temperature, OF ...

405

Heat transfer augmentation in a rectangular channel with a vee-shaped vortex generator  

International Nuclear Information System (INIS)

The unsteady flow and heat transfer are simulated using LES and DNS for a channel with two angled ribs as a vee-shaped vortex generator to augment heat transfer. The vortex generators are attached on the bottom wall of the channel and their angles in respect to the main flow are between 10"o and 30"o. The Prandtl number is 0.71 and the Reynolds numbers based on the inflow velocity and the height of channel are from 200 to 2000. Based on the results of this work, the variations of the Nusselt number, pressure coefficient, bulk temperature, friction factor and Colburn factor with the Reynolds numbers and the incidence angles are provided. The relation between the key parameters of the velocity (friction factor f) and thermal (Colburn factor J) boundary layers is calculated for all cases and their values are compared with the predicted values by the Chilton-Colburn analogy. A comparison between the DNS and LES results is ...

2007-04-01

406

Gynura procumbens Merr. decreases blood pressure in rats by vasodilatation via inhibition of calcium channels  

UK PubMed Central (United Kingdom)

INTRODUCTION:Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensin‐converting enzyme. However, other mechanisms that...Full Text Available

2011-01-01

407

Geologic Structure and Hydrodynamics of Egmont Channel: An Anomalous Inlet at the Mouth of Tampa Bay, Florida  

Science.gov (United States)

... at depths greater than 29 m. Egmont Deep Seismic Stratigraphy Seismic profile data indicate that both the mouth ... 131. CrossRefDuncan, D. S. 1993. Neogene to Recent Seismic Stratigraphy of the Lower ...

408

Fabrication of single nanofluidic channels in poly(methylmethacrylate) films via focused-ion beam milling for use as molecular gates  

International Nuclear Information System (INIS)

Focused-ion beam (FIB) milling provides rapid fabrication of individual cylindrical submicrometer channels with reproducible dimensions (#+-#5% diameters) through 8-#mu#m thick poly(methylmethacrylate) (PMMA) films. PMMA films are spincast on sacrificial Si carriers and sputter-coated with Au before the 30-kV gallium FIB milling process. By adding a trace amount of poly(ethyleneoxide) and poly(dimethylsiloxane) to the PMMA solution before casting, the films can be released for subsequent mounting in microfluidic devices to create hybrid microfluidic-nanofluidic multilevel architectures. In situ FIB sectioning demonstrates the smooth cylindrical surface within the pore. Placing a milled film in contact with an aqueous fluorescein solution fills the channel by capillary action, as verified by confocal fluorescence microscopy. Confocal fluorescence of dyed films reveals that the pores span the thickness of the PMMA film. Small arrays of ...

2004-08-16

409

Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular channel: In natural convection dominated flow regimes  

British Library Electronic Table of Contents (United Kingdom)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated in the natural convection dominated region for a wide range of Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.02win0.025m/s) using a flow rate control valve so that Reynolds number was always about ...

2009-01-01

410

Evolution of Thermal Response Properties in a Cold-Activated TRP Channel  

UK PubMed Central (United Kingdom)

Animals sense changes in ambient temperature irrespective of whether core body temperature is internally maintained (homeotherms) or subject to environmental variation (poikilotherms). Here we show...Full Text Available

411

Dynamic Control of Tunable Sub-optimal Algorithms for Scheduling of Time-varying Wireless Networks  

CERN Document Server

It is well known that for ergodic channel processes the Generalized Max-Weight Matching (GMWM) scheduling policy stabilizes the network for any supportable arrival rate vector within the network capacity region. This policy, however, often requires the solution of an NP-hard optimization problem. This has motivated many researchers to develop sub-optimal algorithms that approximate the GMWM policy in selecting schedule vectors. One implicit assumption commonly shared in this context is that during the algorithm runtime, the channel states remain effectively unchanged. This assumption may not hold as the time needed to select near-optimal schedule vectors usually increases quickly with the network size. In this paper, we incorporate channel variations and the time-efficiency of sub-optimal algorithms into the scheduler design, to dynamically tune the algorithm runtime considering the tradeoff between algorithm efficiency and ...

2009-01-01

412

Characterization of the Decision Network for Wing Expansion in Drosophila Using Targeted Expression of the TRPM8 Channel  

UK PubMed Central (United Kingdom)

After emergence, adult flies and other insects select a suitable perch and expand their wings. Wing expansion is governed by the hormone bursicon and can be delayed under adverse environmental...Full Text Available

2009-03-18

413

Carvedilol targets human K2P3.1 (TASK1) K+ leak channels  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Human K2P3.1 (TASK1) channels represent potential targets for pharmacological management of atrial fibrillation. K2P channels control excitability by stabilizing membrane potential and by expediting repolarization. In the heart, inhibition of K2P currents by class III antiarrhythmic drugs results in action potential prolongation and suppression of electrical automaticity. Carvedilol exerts antiarrhythmic activity and suppresses atrial fibrillation following cardiac surgery or cardioversion. The objective of this study was to investigate acute effects of carvedilol on human K2P3.1 (hK2P3.1) channels. EXPERIMENTAL APPROACH Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record hK2P3.1 currents from Xenopus oocytes, Chinese hamster o...

2011-01-01

414

COSPIN-ANISOTROPY TELESCOPE for ULY - PDS - NASA  

Science.gov (United States)

To calibrate channels A1 to A4 for particles with Z >= 1, tests were done on the IBIS accelerator at AERE, Harwell, which gave protons up to 3 MeV. ...

415

Boiling heat transfer in a small horizontal rectangular channel  

Energy Technology Data Exchange (ETDEWEB)

Compact heat exchangers have traditionally found wide application in the transportation industry, where they are used as evaporators and condensers in vapor compression cycles for air conditioning and refrigeration. Such heat exchangers possess numerous attractive features including high thermal effectiveness, small size, low weight, design flexibility, and pure counterflow, and they can accommodate multiple streams. Today, there is a widespread interest in expanding the range of application of compact heat exchangers to include phase-change heat transfer in the process industries, among others. An overall objective of this effort is to provide the basis for establishing design technology in this area. In the present study, small channel flow boiling heat transfer was extended to a rectangular channel (4.06 {times} 1.70 mm) using refrigerant 12 (R-12). As with the circular tube studies, the flow channel wall was ...

1993-08-01

416

Annealing behavior of radiation damages in metal-silicides  

International Nuclear Information System (INIS)

The annealing behavior of the radiation damage in epitaxial Pd_2Si and NiSi_2 films on Si, due to the implantation of 100 keV Ar ions, is investigated by using the channeling technique with "4He ions. (U.K.).

417

Analysis on depositional system and discussion on ore-formation conditions of channel sandstone type uranium deposit. Taking Dongsheng area, Ordos meso-cenozoic basin as an example  

International Nuclear Information System (INIS)

Applying the theory of depositional system, the depositional facies and depositional systems of the Zhiluo Formation in Dongsheng area are systematically analysed, and the authors proposed that sediments of the Zhiluo Formation are of fluvial facies, and streams of the Zhiluo time experienced three evolution stages, namely: the early braided stream, the middle low sinuosity meandering stream and the late high sinuosity meandering stream. Based on features of paleoclimatic evolution, the Zhiluo Formation is divided into two lithological members. The lower lithological member consists of sediments of braided and low sinuosity meandering streams under humid-ward paleoclimatic conditions forming grey sedimentary formation. The upper member is composed of sediments of meandering streams under arid-hot paleoclimatic conditions representing complex-colored (mainly red) sedimentary formation. It is suggested that uranium mineralization in the study area is of channel ...

2003-03-01

418

Turbulent characteristics of a statified two-phase flow in a horisontal plane channel  

International Nuclear Information System (INIS)

Experimental investigations of the turbulence characteristics of the air flow above the wave surface of the film in the horizontal rectangular channel in the 5-20 m/s velosity range of the air rate change (Reynolds number for the air 120O0-48000, 100-1000 for the film) are carried out. It is shown that intensities of turbulent pulsations of the rate increase with the growth of liquid flow rate in the film especially in the region of large squall waves. The experimental results on the pulsations are presented in the dimensionless form by a universal dependence. Distributions of tangentials of turbulent stresses above the film are obtained, turbulent stresses are compared with friction losses at the phase interface.

1982-02-01

419

Symbol Error Rates of Maximum-Likelihood Detector: Convex/Concave Behavior and Applications  

CERN Document Server

Convexity/concavity properties of symbol error rates (SER) of the maximum likelihood detector operating in the AWGN channel (non-fading and fading) are studied. Generic conditions are identified under which the SER is a convex/concave function of the SNR. Universal bounds for the SER 1st and 2nd derivatives are obtained, which hold for arbitrary constellations and are tight for some of them. Applications of the results are discussed, which include optimum power allocation in spatial multiplexing systems, optimum power/time sharing to decrease or increase (jamming problem) error rate, and implication for fading channels.

2007-01-01

420

Singlet scalars as Higgs imposters at the Large Hadron Collider  

CERN Document Server

An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.

2011-01-01

421

Real-time neutron radiography at McMaster  

International Nuclear Information System (INIS)

The McMaster Neutron Radiography Facility (MNRF) is fortunate to own the only Real-Time Neutron Radiography system in Canada. Current research at the MNRF involves the visualization of gas-liquid and gas-solid two-phase flow in complex channels, such as nuclear fuel channels, using light water, heavy water, freon-134A, slurries, and other fluids. Other research at the MNRF has examined single-phase flow, material purity, film deposition, turbine blades, and automotive parts.

1995-01-01

422

Proton beam monitoring and forming on the target of isotope complex at INR linac  

International Nuclear Information System (INIS)

Special beam extraction channel is used at INR linac for isotope production. It starts from 160 MeV measuring and matching area of accelerator. This choice of beam extraction enables to direct to the target of isotope complex a proton beam of wide energy range up to 160 MeV. It is important for production of different types of nuclides. The measuring results of proton beam behavior in this region are presented. Required beam forming in 160 MeV measuring and matching area of accelerator and in beam extraction channel is discussed.

2010-01-01

423

Peristaltic flow of a couple stress fluid under the effect of induced magnetic field in an asymmetric channel  

Energy Technology Data Exchange (ETDEWEB)

The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters. (orig.)

2011-01-15

424

Peristaltic flow of a couple stress fluid under the effect of induced magnetic field in an asymmetric channel  

British Library Electronic Table of Contents (United Kingdom)

The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters.

2011-01-01

425

Operation principle of microsecond plasma opening switches  

International Nuclear Information System (INIS)

Closing and breaking of current in microsecond megaampere plasma opening switches are considered. Conductivity current scaling in the switch due to plasma acceleration by a magnetic piston is discussed and compared with experimental data. Two ways of determining the width of a current channel are taken up. This channel results from the diffusion of the magnetic field in the plane of the piston followed by the convective ejection of the field frozen in the accelerated plasma flow behind the shock wave into the bridge. Based on experimental data, a scaling law for the voltage on the switch according to the switch parameters is derived. The problem of reverse closing, which limits the efficiency of storage energy extraction into the load, is considered

2009-01-01

426

Mixed convection flow in a horizontal rectangular channel subjected to a horizontal thermal gradient  

British Library Electronic Table of Contents (United Kingdom)

This paper deals with a mixed convection water flow in a horizontal rectangular duct, uniformly heated from one lateral vertical wall and thermally insulated elsewhere. The supplied heat flux induces a secondary flow, which structure is constituted of one longitudinal roll in the considered aspect ratio (??=?1.9), embedded into a return flow of possibly large stream wise extension (up to twenty channel heights). Such situation induces helicoidal trajectories for the fluid flow particles, which contributes to a heat transfer enhancement compared to purely forced convection flow.

2011-01-01

427

Mixed convection flow in a horizontal rectangular channel subjected to a horizontal thermal gradient  

Science.gov (United States)

This paper deals with a mixed convection water flow in a horizontal rectangular duct, uniformly heated from one lateral vertical wall and thermally insulated elsewhere. The supplied heat flux induces a secondary flow, which structure is constituted of one longitudinal roll in the considered aspect ratio (? = 1.9), embedded into a return flow of possibly large stream wise extension (up to twenty channel heights). Such situation induces helicoidal trajectories for the fluid flow particles, which contributes to a heat transfer enhancement compared to purely forced convection flow.

2011-04-01

428

MIMO APP Receiver Processing with Performance-Determined Complexity  

CERN Document Server

Typical receiver processing, targeting always the best achievable bit error rate performance, can result in a waste of resources, especially, when the transmission conditions are such that the best performance is orders of magnitude better than the required. In this work, a processing framework is proposed which allows adjusting the processing requirements to the transmission conditions and the required bit error rate. It applies a-posteriori probability receivers operating over multiple-input multiple-output channels. It is demonstrated that significant complexity savings can be achieved both at the soft, sphere-decoder based detector and the channel decoder with only minor modifications.

2010-01-01

429

Ion beam crystallography of metal-silicon interfaces: Pd-Si(111)  

Energy Technology Data Exchange (ETDEWEB)

The application of medium energy ion scattering in combination with channelling and blocking to the study of the initial stages of palladium silicide formation is discussed. After a brief description of the experimental arrangement and method, the effects on the Rutherford backscattering spectra of depositing small quantities of palladium on clean Si(111) are reported. The uniformity and thermal stability of thin palladium silicide films grown at room temperature were measured. Finally, channelling and blocking results were used to carry out a structural analysis of thin epitaxial Pd/sub 2/Si layers.

1982-07-09

430

Ion beam crystallography of metal-silicon interfaces: Pd-Si(111)  

International Nuclear Information System (INIS)

The application of medium energy ion scattering in combination with channelling and blocking to the study of the initial stages of palladium silicide formation is discussed. After a brief description of the experimental arrangement and method, the effects on the Rutherford backscattering spectra of depositing small quantities of palladium on clean Si(111) are reported. The uniformity and thermal stability of thin palladium silicide films grown at room temperature were measured. Finally, channelling and blocking results were used to carry out a structural analysis of thin epitaxial Pd_2Si layers. (Auth.).

431

Integrity assessment of pressure tubes for Wolsung unit 2  

Energy Technology Data Exchange (ETDEWEB)

To improve operational safety of the fuel channel for Wolsung units the recommended primary heat transport system (PHTS) operating guidelines were developed, which provides a safe operation window in terms of pressure and temperature to maintain fuel channel integrity, which is similar to pressure-temperature curves used for primary pressure boundary integrity in PWRs and deterministic Leak-Before Break (LBB) analyses were conducted using recent understanding of delayed hydride cracking (DHC) mechanism. In addition, a comparative assessment of LBB analysis was made using the procedures of Fitness For Service Guidelines(FFSG) for pressure tubes rev. 0 and rev. 1.

1997-10-01

432

Horizontal liquid film-mist two-phase flow. I - Concentration distribution and diffusivity of entrained liquid droplets  

Science.gov (United States)

The entrainment flow rate distribution, the gas velocity profile, and the concentration profile of droplets across the channel cross section in fully developed region of a horizontal rectangular channel of 150mm width and 50mm height were measured. The concentration profile of droplets was expressed by a simple equation based on a constant diffusion coefficient model. From this equation the effects of gravity and turbulent diffusion of droplets on the concentration profile were evaluated. The characteristic mean settling velocity of a group of droplets with various diameters was derived, and using this value the mean diffusion coefficient of the group of droplets was obtained

1980-06-01

433

Horizontal liquid film-mist two-phase flow, 1  

International Nuclear Information System (INIS)

The entrainment flow rate distribution, the gas velocity profile, and the concentration profile of droplets across the channel cross section in fully developed region of a horizontal rectangular channel of 150 mm width and 50 mm height were measured. The concentration profile of droplets was expressed by a simple equation based on a constant diffusion coefficient model. From this equation the effects of gravity and turbulent diffusion of droplets on the concentration profile were evaluated. The characteristic mean settling velocity of a group of droplets with various diameters was derived, and using this value the mean diffusion coefficient of the group of droplets was obtained. (author).

1980-01-01

434

Final state interactions in the decays J/{psi}{yields}VPP  

Energy Technology Data Exchange (ETDEWEB)

We investigate the interplay between crossed channel final state interactions and the constraints from two-particle unitarity for the reactions J/{psi}{yields}V{pi}{pi} and VK anti K, where V is either {omega} or {phi}. Using a model where the parameters are largely constrained by other sources, we find that, although small, crossed channel final state interaction can influence the amplitudes considerably, in special areas of phase space. These results cast doubt on the inapplicability of unitarity constraints on production amplitudes as recently claimed in the literature. (orig.)

2009-09-15

435

Emission of photons by electrons and positrons passing through a thin single crystal  

Energy Technology Data Exchange (ETDEWEB)

We consider the radiation of particles (electrons and positrons) undergoing planar channeling in a single crystal of small thickness L. We show that for Lapprox...pi..b/theta/sub L/, where b is the lattice constant and theta/sub L/ is the Lindhard angle, in addition to the principal maxima of spontaneous radiation of channeled particles in the spectrum there are additional interference maxima, and the positions of all maxima of the radiation intensity depend on L. We discuss the dependence of the intensity of radiation at various frequencies on the crystal thickness.

1984-07-01

436

Effective-index modeling of channel plasmon polaritons  

Science.gov (United States)

Effective-index approach is applied for modeling of channel plasmon polaritons (CPPs) propagating in rectangular grooves (trenches) and triangular (V-shaped) grooves in gold, accounting for the main features of CPP guiding and elucidating its underlying physics. The effective indexes of CPP modes along with the corresponding propagation lengths are calculated for different configurations and wavelengths while varying the groove depth. The results obtained allow one to identify the parameter range for realizing the single-mode CPP guiding featuring subwavelength confinement and moderate propagation loss at telecom wavelengths.

2006-10-01

437

Coupled-channels analysis of /sup 12/C and /sup 7/Li scattering using the Watanabe superposition model  

Energy Technology Data Exchange (ETDEWEB)

Angular distributions for the elastic and inelastic scattering of /sup 12/C at 80 MeV by /sup 88/Sr and of /sup 7/Li at 36, 42 and 48 MeV by /sup 54/Fe have been analysed. The optical potentials of /sup 12/C and /sup 7/Li ions are calculated in terms of the alpha-particle and triton optical potentials. Coupled-channels calculations using these potentials are performed. Good fits to the experimental data and the phenomenological calculations are obtained for /sup 12/C projectiles.

1983-11-01

438

Convoy electron production in polycrystalline and monocrystalline targets  

Energy Technology Data Exchange (ETDEWEB)

The velocity distribution of electrons ejected close to the forward direction by 0.8-2 MeV/A ions traversing various solid targets, including a Au monocrystal, is measured in coincidence with emerging charge-selected ions. The velocity spectrum is observed to be independent of outgoing projectile velocity and charge state for polycrystalline targets. Measurements on the Au crystal under channeling conditions show dependences on final charge state, and are tentatively explained by assuming that the main contribution to the production yield comes from the non-channeled fraction of the ions. A simple model for the creation of the forward-ejected electrons is proposed, which accounts for most of the experimental findings.

1980-01-01

439

Bend loss for channel plasmon polaritons  

Science.gov (United States)

Using near-field optical microscopy, the authors investigate propagation of channel plasmon polaritons excited in the wavelength range of 1425-1640 nm along smoothly bent and split V-shaped grooves milled in a gold film. We find that for 0.6-?m-wide and 1.1-?m-deep grooves bent with the smallest curvature radius of ?0.83 ?m, the double bend (for S bends) and splitting (for Y splitters) losses decrease for longer wavelengths approaching (in the wavelength range of 1600-1640 nm) the levels of ~0 and 0.5 dB, respectively.

2006-10-01

440

Experimental study on heat transfer augmentation for high heat flux removal in rib-roughened narrow channels  

Energy Technology Data Exchange (ETDEWEB)

Frictional pressure drop and heat transfer performance in a very narrow rectangular channel having one-sided constant heat flux and repeated-ribs for turbulent flow have been investigated experimentally, and their experimental correlations were obtained using the least square method. The rib pitch-to-height ratios(p/k) were 10 and 20 while holding the rib height constant at 0.2mm, the Reynolds number(Re) from 2,414 to 98,458 under different channel heights of 1.2mm, 2.97mm, and 3.24mm, the rib height-to-channel equivalent diameter(k/De) of 0.03, 0.04, and 0.09 respectively. The results show that the rib-roughened surface augments heat transfer 2-3 times higher than that of the smooth surface with the expense of 2.8-4 times higher frictional pressure drop under Re=5000-10{sup 5}, p/k=10, and H=1.2mm. Experimental results obtained by channel height, H=1.2mm shows a little bit higher heat transfer and ...

1997-07-01

442

The Quantum Information Revolution: 101 Uses for Schroedingers Cat  

ScienceCinema

...exactly five years ago that english poet ? laws ...

443

Study on institutionalization of risk-informed performance-based regulation  

International Nuclear Information System (INIS)

In this study, for the institutionalization of risk informed and performance based regulation in Korea, the latest technical movements of overseas countries are examined and reviewed. And the issues that was found when license change petition using risk information was submitted in Korean regulatory body are reviewed. Based on these review, the applicable areas to domestic situation will be found and proposed. This study can contribute to setting up the proper direction for the institutionalization of risk informed and performance based regulation

2007-04-22

444

Study on institutionalization of risk-informed performance-based regulation  

Energy Technology Data Exchange (ETDEWEB)

In this study, for the institutionalization of risk informed and performance based regulation in Korea, the latest technical movements of overseas countries are examined and reviewed. And the issues that was found when license change petition using risk information was submitted in Korean regulatory body are reviewed. Based on these review, the applicable areas to domestic situation will be found and proposed. This study can contribute to setting up the proper direction for the institutionalization of risk informed and performance based regulation.

2003-02-15

445

Security Considerations For Network-Centric Weapon ...  

Science.gov (United States)

... strategies. Computer and network security deals with cryptography, authentication, and attacks on software. Information ...

2009-09-01

447

Realistic and Affordable Cyberware Opponents for the ...  

Science.gov (United States)

... Therefore, as the information management capabilities of military forces increase, there is a corresponding need for improved security for the ...

2003-06-01

448

QCCM - Center for NMR Quantum Information Processing  

Science.gov (United States)

... decoherence. Descriptors : *QUANTUM COMPUTING, NUCLEAR MAGNETIC RESONANCE, JOSEPHSON JUNCTIONS. Subject ...

2011-02-16

450

Phractura bovei  

Science.gov (United States)

... Lower Congo. The type locality is Vivi, near Matadi. (click map to view full version) No information ... ...

451

Method of bistable optical information storage using antiferroelectric phase PLZT ceramics  

Energy Technology Data Exchange (ETDEWEB)

A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field.

1990-01-01

452

Incorporating the e-HIM[R] Virtual Lab into the Health Information Administration Professional Practice Experience  

Science.gov (United States)

This article will highlight the experiences of two baccalaureate Health Information Administration (HIA) programs in the adoption of the American Health Information Management Association's (AHIMA) e-HIM Virtual Laboratory (Virtual Lab) into the Professional Practice Experience (PPE). Information is provided describing the implementation of the Virtual Lab, issues that were encountered, and subsequent feedback from students and faculty regarding this new technology.

2010-12-01

453

Implementing Advanced Technologies in the Republic of ...  

Science.gov (United States)

... personal computers low-cost information management capabilities to television's uncanny ability to motivate and communicate. ...

1994-03-01

454

Hydrobia rheophila  

Science.gov (United States)

... River on river rapids at Kala Kala near Matadi. (click map to view full version) No information ... ...

456

FDH radiological design review guidelines  

Energy Technology Data Exchange (ETDEWEB)

These guidelines discuss in more detail the radiological design review process used by the Project Hanford Management Contractors as described in HNF-PRO-1622, Radiological Design Review Process. They are intended to supplement the procedure by providing background information on the design review process and providing a ready source of information to design reviewers. The guidelines are not intended to contain all the information in the procedure, but at points, in order to maintain continuity, they contain some of the same information.

1998-09-29

457

Erectile Dysfunction  

Science.gov (United States)

... Remember Hope through Research For More Information Acknowledgments What is erectile dysfunction (ED)? ED is the inability to get or ...

458

Continuous Strategy Development for Effects-Based ...  

Science.gov (United States)

... BAE Systems Advanced Information Technologies, Inc. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. ...

2006-02-01

459

Basic physics of radiotracers  

Energy Technology Data Exchange (ETDEWEB)

This two-volume reference uses many equations to provide detailed information on atomic and nuclear decay phenomena.

1983-01-01

460

A Report on the Evaluation of the NSF's Informal Science Education (ISE) Program  

Science.gov (United States)

... science in places outside of schools, with materials and activities initially not developed for ...

461

Working with activity theory: Context, technology, and information behavior  

British Library Electronic Table of Contents (United Kingdom)

Abstract Over the last 7 years, the AIMTech Research Group in the University of Leeds has used cultural-historical activity theory (CHAT) to inform a range of research activities in the fields of information behavior and information systems. In this article, we identify certain openings and theoretical challenges in the field of information behavior, which sparked our initial interest in CHAT: context, technology, and the link between practice and policy. We demonstrate the relevance of CHAT in studying information behavior and addressing the identified openings and argue that by providing a framework and hierarchy of activity-action-operation and semantic tools, CHAT is able to overcome many of the uncertainties concerning information behavior research. In particular, CHAT provides resear...

2011-01-01

462

To talk or not to talk: exploring culturally diverse patients' health information communication choices.  

Science.gov (United States)

As care shifts from institutional to home- and community-based settings, consumer health information technology (IT) must be designed to support patients' new health information management responsibilities. We developed and piloted a new methodology grounded in social network analysis and human factors engineering to explore two often overlooked aspects of this phenomenon: the task of health information communication with members of the social network and the context of culture. Such knowledge is necessary to inform the appropriate design of consumer health IT. We asked a culturally diverse sample of participants to describe what, to whom, why, and how they communicate health information and to provide direct feedback about the methodology. The methodology was acceptable to all participants and able to capture similarities and differences in their health ...

2010-11-13

463

Navy Occupational Health Information Management System (NOHIMS). Hazardous Materials Control Module. Users' manual  

Energy Technology Data Exchange (ETDEWEB)

The Hazardous Materials Control Module (HMC) is one module of four for the Industrial Health component. The HMC module was designed to inform employees of health and safety hazards in the workplace and to track the movement of hazardous materials through the facility. The module performs these functions by maintaining health and safety data on hazardous materials used in the facility, and by tracking who requests information about any hazardous materials. The HMC module gets its information from two sources. The first one is the Hazardous Materials Information System (HMIS), this is a national system that is used by the Department of Defense. It is loaded on to the system via tapes that contain all safety, health and transportation information about a particular product. The second is Material Safety Data Sheets (MSDS) that are procured by a particular site. This ...

1987-01-16

464

Informal Employment and the Role of Regional Governance  

British Library Electronic Table of Contents (United Kingdom)

Abstract The aim of this paper is to provide an explanation to why the degree of informal employment may vary substantially between different regions within a country. In Brazil, 45% of workers in the urban labor force are employed informally. The degree of informal employment, however, varies substantially across regions, with some cities having 20% and others having 80% or more of their labor force in the informal sector. The hypothesis assessed here is that the quality of local governance-or government effectiveness-affects the decisions of workers and businesses as to whether to participate in the formal or the informal sector. The empirical analysis, based on data from 5500 Brazilian municipalities, shows that informal employment is lower in regions with better governance, higher aver...

2011-01-01

465

Implementing network security guidelines in health care information systems.  

Science.gov (United States)

A Health Care Establishment (HCE) is an establishment where medical services are rendered. These services are provided by the health care personnel. The infrastructure of a HCE may include Information Technology (IT) equipment that stores and processes HC information. The spread of distributed information technology in HCEs have necessitated the implementation of Network Security in Health Care Information System (HCISs), to assure confidentiality, integrity and availability of HC information being transmitted across HC networks. This paper presents a road map in implementing Network Security guidelines for the provision of Network Security in HCEs, work carried out within the Secure Environment for Information Systems in Medicine (SEISMED) project under the Advanced Informatics in Medicine (AIM) programme. PMID:8591295

1995-01-01

466

Hanford facility dangerous waste permit application, general information portion  

Energy Technology Data Exchange (ETDEWEB)

The `Hanford Facility Dangerous Waste Permit Application` is considered to be a single application organized into a General Information Portion (this document, DOE/RL-91-28) and a Unit- Specific Portion. The scope of the General Information Portion includes information that could be used to discuss operating units, units undergoing closure, or units being dispositioned through other options. Documentation included in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units. A checklist indicating where information is contained in the General Information Portion, in relation to the Washington State Department of Ecology guidance documentation, is located in the Contents Section. The intent of the General Information Portion is: (1) to provide an overview of the Hanford ...

1996-07-29

467

Information on Hanford site cribs and septic systems  

Energy Technology Data Exchange (ETDEWEB)

This document provides information on septic systems with a design capacity of greater than 14,500 gal/d and cribs submitted as requested by the Washington State Department of Ecology. Data for this submittal were taken from the Waste Information Database System (WIDS) and the Hanford Environmental Compliance Record (HECR) database. The current definition used in WIDS for an ''inactive facility'' is one that either no longer receives waste or plans to in the future. Information concerning the deactivation method for a facility is included when such information is available.

1988-05-01

468

Impact of more intensive written information in patients having radical radiation therapy: Results of a prospective randomized phase III trial  

International Nuclear Information System (INIS)

Background and purpose: A diagnosis of malignancy and its treatment is a very stressful time for patients and their families. This study was conducted to determine the impact of more intensive written information on patients' anxiety levels. The secondary aim was to determine the impact of this information on patients' satisfaction levels. Materials and methods: This prospective randomized trial consisted of patients with a pathological diagnosis of cancer having radical radiotherapy (RT). Patients were randomized to receive the more intensive information (including written information and a telephone call from the research nurse) or not to receive the more intensive information at the time of their initial consultation with the radiation oncologist. Study questionnaires measuring anxiety (STAI form) were completed prior to their first consultation (baseline) at the time of ...

2010-08-01

469

Contaminant transport in fracture networks with heterogeneous rock matrices. The Picnic code  

Energy Technology Data Exchange (ETDEWEB)

In the context of safety assessment of radioactive waste repositories, complex radionuclide transport models covering key safety-relevant processes play a major role. In recent Swiss safety assessments, such as Kristallin-I, an important drawback was the limitation in geosphere modelling capability to account for geosphere heterogeneities. In marked contrast to this limitation in modelling capabilities, great effort has been put into investigating the heterogeneity of the geosphere as it impacts on hydrology. Structural geological methods have been used to look at the geometry of the flow paths on a small scale and the diffusion and sorption properties of different rock materials have been investigated. This huge amount of information could however be only partially applied in geosphere transport modelling. To make use of these investigations the 'PICNIC project' was established as a joint cooperation of PSI/Nagra and QuantiSci to provide a new ...

2001-02-01

470

Path integrals in quantum physics. Lectures given at ETH Zurich during summer semester 1997; Pfadintegrale in der Quantenphysik. Vorlesung im Sommersemester 1997 an der ETH Zuerich  

Energy Technology Data Exchange (ETDEWEB)

This lectures aim at giving graduate students an introduction to a working knowledge of path integral methods in a wide variety of fields in physics. Consequently, the the lecture notes are organized in three main parts dealing with non-relativistic quantum mechanics, many-body physics and field theory. In the first part the basic concepts of path integrals are developed in the usual heuristic, non-mathematical way followed by the standard examples of quadratic Lagrangians for which the path integrals can be solved exactly. Applications include semi-classical expansions, scattering problems and the representation of Green functions as path integrals. In the last chapter of this part it is shown how (euclidean) path integrals can be treated numerically by Monte-Carlo methods with a program for the anharmonic oscillator as an explicit example. The second part deals with the application of path integrals in statistical mechanics and many-body problems. Various chapters treat the partition ...

1997-12-01

471

On foundation of the generalized Nambu mechanics  

International Nuclear Information System (INIS)

We outline basic principles of a canonical formalism for the Nambu mechanics - a generalization of Hamiltonian mechanics proposed by Yoichiro Nambu in 1973. It is based on the notion of a Nambu bracket, which generalizes the Poisson bracket - a 'binary'' operation on classical observables on the phase space - to the 'multiple' operation of higher order n#>=#3. Nambu dynamics is described by the phase flow given by Nambu-Hamilton equations of motion - a system of ODE's which involves n-1 'Hamiltonians'. We introduce the fundamental identity for the Nambu bracket - a generalization of the Jacobi identity - as a consistency condition for the dynamics. We show that Nambu bracket structure defines a hierarchy of infinite families of 'subordinated' structures of lower order, including Poisson bracket structure, which satisfy certain matching conditions. The notion of Nambu bracket enables us to define Nambu-Poisson manifolds - phase spaces for the Nambu mechanics, which turn out to be ...

472

Measurement of magnetic fields in the Area Metropolitana  

International Nuclear Information System (INIS)

The operation and proper handling of equipment for measuring EMR-300 electromagnetic waves are studied and apply that knowledge to determine which areas of the metropolitan area are mostly affected by exposure to the emission of radiation. This team is able to measure magnetic field strength, electric field strength and power density, also can measure the most important parameters in a simple manner. International standards provide maximum values for these parameters that limit human exposure to such radiation. These standards are based on epidemiological several and laboratory that have been carried out in order to determine in which circumstances a biological entity is exposed to a level of radiation that can cause harm to their health. It focuses on measuring the level of radiation in certain areas of interest, which were chosen because are areas with high population density and also in proximity to antennas that emit electromagnetic waves. Before carrying out the data collection ...

473

Electronic topological transition in an n-BiSb semiconductor alloy in the quantum limit range of magnetic fields for H-parallel C{sub 2}  

Science.gov (United States)

The galvanomagnetic properties of single-crystal samples of the Bi{sub 0.93}Sb{sub 0.07} semiconductor alloy with the electron density n = 1.6 x 10{sup 17} cm{sup -3} in magnetic fields up to 14 T at T = 1.6 K have been investigated. The resistivity {rho} and Hall coefficient R have been measured as functions of the magnetic field directed along the binary axis of a crystal for a current flowing through a sample along the bisector axis; i.e., the components {rho}{sub 22} and R{sub 32,1} have been measured. The strong anisotropy of the electron spectrum of the samples makes it possible to separately observe quantum oscillations of the magnetoresistance {rho}{sub 22}(H) for H -parallel C{sub 2} in low magnetic fields for two equivalent ellipsoids with small extremal cross sections (secondary ellipsoids) and in high magnetic fields for electrons of the ellipsoid with a large extremal cross section (main ellipsoid). An increase in the energy of the electrons of secondary ellipsoids in the ...

2010-08-15

474

Development of Intelligent Setting System for Fracture Based on X-Ray Image  

Energy Technology Data Exchange (ETDEWEB)

In order to achieve micro-wound, intelligence and high efficiency for fracture setting, intelligent setting system for fracture is proposed in accordance with biomechanics and fracture therapy theory. In the comprehensive medical system based on C-shape-arm X-machine, image processing and analysis is the core, programmable logical controller and stepping motor are important driving parts controlling mechanical parts. Six degree of freedom dynamics sensor ensures to control accurately force and moment. On the foundation of analyzing X-ray image peculiarities, method of processing and analysis is put forward, combining time domain with frequency domain. After mining domain knowledge in depth, setting actions is quantized into three non-continuous steps and is parameterized into two angles and one distance aiming at femoral-neck fracture. Objective features are extracted by virtue of three power polymerization curved surface fitting. Master-slave reference frame is ...

2006-10-15

475

Developing common information elements for renewable energy systems: summary and proceedings of the SERI/AID workshop  

Energy Technology Data Exchange (ETDEWEB)

This report describes the activities, conclusions, and recommendations of the Workshop on Evaluation Systems for Renewable Energy Systems sponsored by the Agency for International Development and SERI, held 20-22 February 1980 in Golden, Colorado. The primary objectives of the workshop was to explore whether it was possible to establish common information elements that would describe the operation and impact of renewable energy projects in developing countries. The workshop provided a forum for development program managers to discuss the information they would like to receive about renewable energy projects and to determine whether common data could be agreed on to facilitate information exchange among development organizations. Such information could be shared among institutions and used to make informed judyments on the economic, technical, and social feasibility of the ...

1980-06-01

476

Assessing the effects of the HIPAA privacy rule on release of patient information by healthcare facilities.  

Science.gov (United States)

The HIPAA privacy rule (HIPAA) has had both positive and negative effects on the release of patient information by healthcare facilities. Although the intention of HIPAA was to protect patient privacy and to promote security and confidentiality of patient information, it has had unintended consequences for facilities. To identify some of these unintended effects, two expert panels of health information management directors from healthcare facilities participated in the nominal group technique meetings. They identified 70 barriers related to release of patient information associated with the implementation of HIPAA. The perceived biggest barriers were increases in the public's misunderstanding about release of patient information, lack of an umbrella policy or regulation defining infractions and enforcement that allows individual institutions to make their own interpretations, and ...

2007-03-23

477

Wolsong 2,3 and 4 fuel channel analysis during a large break loss of coolant accident with loss of ECCS injection  

International Nuclear Information System (INIS)

Wolsong 2,3 and 4 fuel channel analysis during a large break loss of coolant accident with loss of ECCS injection (LOCA/LOECC) is performed to obtain the heat load to moderator. Because the single channel analysis requires the establishment of the safety codes and their input decks, the present study follows the same safety analysis methodology found in FSAR of Wolsong 2,3 and 4. From this work we obtain the safety tools such as CATHENA MOD3.5b/Rev.1 and CHAN-II/A MOD2 codes, and their code modeling in a form of code input deck. The analysis consists of two parts: front-end (blowdown period) and back-end. For the front-end analysis the fuel and pressure tube (PT) temperatures, and PT circumferential strains at the end of front-end as well as fuel channel depressurization are calculated using CATHENA code and used as initial and boundary conditions for back-end analysis. The back-end period under the conditions of prolonged ...

2002-10-01

478

The Infrared Camera (IRC) for the ASTRO-F infrared astronomical satellite  

Science.gov (United States)

The Infrared Camera (IRC) is one of the scientific focal plane instruments on board the ASTRO-F infrared astronomical satellite. The IRC is designed for wide field imaging and slit-less spectroscopic observations at near- and mid-infrared wavelengths. The IRC consists of three channels; NIR, MIR-S and MIR-L, each of which covers wavelengths of 2-5, 5-12 and 12-26 micron, respectively. All channels adopt compact refractive optical designs. Large format array detectors (a InSb 512 x 412 array and two Si:As IBC 256 x 256 arrays) are employed. Each channel has 10 x 10 arcminutes wide FOV with diffraction-limited angular resolution of 70cm aperture of the liquid helium cooled telescope at wavelengths over 5 micron. A 6-position filter wheel is placed at the aperture stop in each channel, and has three band-pass filters, two grisms/prisms and a mask for dark current measurements. The 5 sigma sensitivity of ...

2004-01-01

479

3D time-of-flight MR angiography of the intracranial vessels: optimization of the technique with water excitation, parallel acquisition, eight-channel phased-array head coil and low-dose contrast administration  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study is three folds: to compare the eight-channel phased-array and standard circularly polarized (CP) head coils in visualiazation of the intracranial vessels, to compare the three-dimentional (3D) time-of-flight (TOF) MR angiography (MRA) techniques, and to define the effects of parallel imaging in 3D TOF MRA. Fifteen healthy volunteers underwent 3D TOF MRA of the intracranial vessels using eight-channel phased-array and CP standard head coils. The following MRA techniques were obtained on each volunteer: (1) conventional 3D TOF MRA with magnetization transfer; (2) 3D TOF MRA with water excitation for background suppression; and (3) low-dose (0.5 ml) gadolinium-enhanced 3D TOF MRA with water excitation. Results are demonstrating that water excitation is a valuable background suppression technique, especially when applied with an eight-channel phased-array head coil. For central and proximal portions of the ...

2004-11-01

480

The impact of available information on negotiation results  

British Library Electronic Table of Contents (United Kingdom)

Negotiation is the most famous tool for reaching an agreement between parties. Usually, the different parties can be modeled as a buyer and a seller, who negotiate about the price of a given item. In most cases, the parties have incomplete information about one another, but they can invest money and efforts in order to acquire information about each other. This leads to the question of how much each party will be willing to invest on information about its opponent, prior to the negotiation process. In this paper, we consider the profitability of automated negotiators acquiring information on their opponents. In our model, a buyer and a seller negotiate on the price of a given item. Time is costly, and incomplete information exists about the reservation price of both parties. The reservatio...

2010-01-01

481

Issues of security and network security in Health Care Information Systems.  

Science.gov (United States)

A Health Care Establishment (HCE) is an establishment where medical services are rendered. The above services are provided by the health care personnel. The infrastructure of a HCE may include Information Technology (IT) equipment that stores and processes HC information. Previously, IT equipment consisted solely of stand-alone systems, whereas in recent years, the trend has been towards computer networks and distributed systems in HCEs. The spread of distributed information technology in HCEs have necessitated the implementation of Security in HCISs, to assure confidentiality, integrity and availability of HCE information. This paper discusses the issues of Security and Network Security in Health Care Information Systems (HCISs). It also suggests a method in establishing Network Security Guidelines and describes Principles for the provision of Network Security in HCEs. ...

1996-01-01

482

Cosmological Information from Lensed CMB Power Spectra  

CERN Document Server

Gravitational lensing distorts the cosmic microwave background (CMB) temperature and polarization fields and encodes valuable information on distances and growth rates at intermediate redshifts into the lensed power spectra. The non-Gaussian bandpower covariance induced by the lenses is negligible to l=2000 for all but the B polarization field where it increases the net variance by up to a factor of 10 and favors an observing strategy with 3 times more area than if it were Gaussian. To quantify the cosmological information, we introduce two lensing observables, characterizing nearly all of the information, which simplify the study of non-Gaussian impact, parameter degeneracies, dark energy models, and complementarity with other cosmological probes. Information on the intermediate redshift parameters rapidly becomes limited by constraints on the cold dark matter density and initial amplitude of ...

2006-01-01

483

Constrained information maximization by free energy minimization  

British Library Electronic Table of Contents (United Kingdom)

In this paper we introduce free energy-based methods to constrain mutual information maximization, developed to realize competitive learning. The new method is introduced to simplify the computational procedures of mutual information and to improve the fidelity of representation and to stabilize learning. First, the free energy is effective in simplifying the computation procedures of mutual information because we need not directly compute mutual information, which needs heavy computation, but only deals with partition functions. With partition functions, computational complexity is significantly reduced. Second, fidelity to input patterns can be improved because training errors between input patterns and connection weights are implicitly incorporated. This means that mutual information is...

2011-01-01

484

Turbulent heat transfer augmentation using microscale disturbances inside the viscous sublayer  

Energy Technology Data Exchange (ETDEWEB)

The authors report here on an experimental study of heat transfer augmentation in turbulent flow. Enhancement strategies employed in this investigation are based on the near-wall mixing processes induced in the sublayer through appropriate wall and near-wall streamwise-periodic disturbances. Experiments are performed in a low-turbulence wind-tunnel with a high-aspect-ratio rectangular channel having either (a) two-dimensional periodic microgrooves on the wall, or (b) two-dimensional microcylinders placed in the immediate vicinity of the wall. It is found that microdisturbances placed inside the sublayer induce favorable heat-transport augmentation with respect to the smooth-wall case, in the near-analogous momentum and heat transfer behavior are preserved; a roughly commensurate increase in heat and momentum transport is termed favorable in that it leads to a reduction in the pumping power penalty at fixed heat removal rate. The study shows that this favorable ...

1992-05-01

485

Turbulent heat transfer augmentation and friction in periodic fully developed channel flows  

Energy Technology Data Exchange (ETDEWEB)

Measurements are presented of the distribution of average friction factors (f) as well as local and average ({ovr Nu}) heat transfer coefficients for fully developed channel flows with two rib-roughened opposite walls. The temperature measurements were made by using both a laser holographic interferometer and thermocouples. In addition, the reattachment length was determined by flow visualization. The Reynolds number (Re) was varied from 5.0 {times} 10{sup 3} to 5.4 {times} 10{sup 4}; the rib pitch-to-height ratios (Pi/H) were 10, 15, 20; and the rib height-to-hydraulic diameter ratios (H/De) were 0.063, 0.081, and 0.106. The detailed results allowed the peaks of heat transfer augmentation and the regions susceptible to hot spots to be located and allowed the relative contribution of the rib surface and the channel wall to the heat transfer augmentation to be determined. Moreover, relative to a smooth duct, the enhancement of both {ovr Nu} and ...

1992-02-01

486

Thermal analysis of spent fuel in rehearsal and emergency storage facility (RESF) under station blackout (SBO) in TAPS - 4  

International Nuclear Information System (INIS)

The RESF is utilized for storage of spent fuel under emergency conditions as well as for testing of FM heads. It receives cooling supply from the PHT Pressurizing pumps and after removal of decay heat from the spent fuel it goes to the D2O Storage Tank. The geometry of the RESF system is such that it can not sustain the thermosyphon loop during SBO, due to high frictional forces. To achieve the sustained thermosyphon, modifications in the design were suggested viz., removal of the steam trap and the relief valve above it and replacement by a solenoid valve (SV-16). In the event of SBO, SV-16 will open on 'RESF channel temperature high' signal and connect to FT D2O tank. The tank, being at atmospheric pressure and at lower elevation, will provide higher cooling flow rate through the RESF channel. D2O is periodically removed from the FT D2O tank by operating a Class-II pump intermittently. The analysis was done for the modified RESF system ...

2006-11-13

487

Stable p-channel polysilicon thin film transistors fabricated by laser doping technique  

Energy Technology Data Exchange (ETDEWEB)

In this work we present the electrical characterization of non self-aligned p-channel thin film transistors fabricated by using laser doping technique for source/drain contact formation and gate oxide deposited at room temperature by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapour Deposition. These techniques are suitable for a very low temperature process for TFT fabrication. The output characteristics show a current increase at high drain voltage ('kink' effect) rather moderate, if compared to self aligned polysilicon TFTs, probably due to the gradual doping profile induced by laser doping process. After bias stress at low gate voltage and high drain voltage condition a strong reduction of kink current has been observed in the output characteristics at high drain voltage, whereas minor changes has been observed in the transfer characteristics. This behaviour is similar to what observed in n-channel Gate ...

2005-09-01

488

Stable p-channel polysilicon thin film transistors fabricated by laser doping technique  

International Nuclear Information System (INIS)

In this work we present the electrical characterization of non self-aligned p-channel thin film transistors fabricated by using laser doping technique for source/drain contact formation and gate oxide deposited at room temperature by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapour Deposition. These techniques are suitable for a very low temperature process for TFT fabrication. The output characteristics show a current increase at high drain voltage ('kink' effect) rather moderate, if compared to self aligned polysilicon TFTs, probably due to the gradual doping profile induced by laser doping process. After bias stress at low gate voltage and high drain voltage condition a strong reduction of kink current has been observed in the output characteristics at high drain voltage, whereas minor changes has been observed in the transfer characteristics. This behaviour is similar to what observed in n-channel Gate Overlapped Thin Film ...

2005-09-01

489

Multi-objective optimization of a dimpled channel for heat transfer augmentation  

Energy Technology Data Exchange (ETDEWEB)

Staggered arrays of dimples printed on opposite surfaces of a cooling channel is formulated numerically and optimized with hybrid multi-objective evolutionary algorithm and Pareto optimal front. As Pareto optimal front produces a set of optimal solutions, the trends of objective functions with design variables are predicted by hybrid multi-objective evolutionary algorithm. The problem is defined by three non-dimensional geometric design variables composed of dimpled channel height, dimple print diameter, dimple spacing, and dimple depth, to maximize heat transfer rate compromising with pressure drop. Twenty designs generated by Latin hypercube sampling were evaluated by Reynolds-averaged Navier-Stokes solver and the evaluated objectives were used to construct Pareto optimal front through hybrid multi-objective evolutionary algorithm. The optimum designs were grouped by k-means clustering technique and some of the clustered points were evaluated ...

2008-12-15

490

Multi-objective optimization of a dimpled channel for heat transfer augmentation  

Science.gov (United States)

Staggered arrays of dimples printed on opposite surfaces of a cooling channel is formulated numerically and optimized with hybrid multi-objective evolutionary algorithm and Pareto optimal front. As Pareto optimal front produces a set of optimal solutions, the trends of objective functions with design variables are predicted by hybrid multi-objective evolutionary algorithm. The problem is defined by three non-dimensional geometric design variables composed of dimpled channel height, dimple print diameter, dimple spacing, and dimple depth, to maximize heat transfer rate compromising with pressure drop. Twenty designs generated by Latin hypercube sampling were evaluated by Reynolds-averaged Navier-Stokes solver and the evaluated objectives were used to construct Pareto optimal front through hybrid multi-objective evolutionary algorithm. The optimum designs were grouped by k-means clustering technique and some of the clustered points were evaluated ...

2008-12-01

491

Multi-Objective Optimization of Cooling Channel Roughened by Dimples  

Science.gov (United States)

Shape optimization of heat transfer augmentation device employed in turbine blade internal cooling passage has been performed numerically using single as well as multi-objective optimization procedures. Polynomial response surface approximation method and multi-objective genetic algorithm are used for single and multi-objective optimizations, respectively. Problem to enhance heat transfer rate considering staggered dimples on single surface of cooling passage has been formulated, and Reynolds-averaged Navier-Stokes equations are solved to analyze the flow field and the heat transfer. Three design variables defining channel and dimple dimensions, and two objective functions related to Nusselt number and friction drag are employed. Latin hypercube sampling is used to generate sampling points in design space, and the evaluated objectives are used to generate a set of optimal designs. Optimal shapes show higher heat transfer rates in the case of lower ...

2008-01-01

492

Modeling of boiling- and tow-phase flow in offset-strip-fin heat-exchanger geometries  

Energy Technology Data Exchange (ETDEWEB)

The two-phase heat-transfer and pressure-drop characteristics of offset-strip-fin heat-exchanger geometries are examined using both experimental and analytical modeling techniques. Newly-obtained boiling-flow heat-transfer data are presented for two large-scale offset fin geometries at low-to-moderate wall-superheat conditions. Data for which nucleate boiling appeared to be completely suppressed were analyzed together with similar results for other offset fin surfaces to study the effects of channel dimensions on the convective evaporation component of the local heat transfer coefficient. Although these data were found to be well correlated in terms of modified forms of the F and Martinelli parameters used in previous studies of round-tube flows, a single F-factor correlation valid for all combinations of fin and channel dimensions did not appear to exist. The two-phase pressure-drop characteristics of offset-fin surfaces were found to be much ...

1988-01-01

493

Localized deformation and IASCC initiation in austenitic stainless steels  

International Nuclear Information System (INIS)

Localized deformation may play a key role in the underlying mechanism of irradiation assisted stress corrosion cracking (IASCC) in light water reactor core components. In this study, four austenitic alloys, 18Cr8Ni, 15Cr12Ni, 13Cr15Ni and 21Cr32Ni, with different stacking fault energies were irradiated to 1 and 5 dpa at 360 deg. C using 3.2 MeV protons. Interrupted constant extension rate tensile (CERT) tests were conducted in a simulated BWR environment to determine IASCC susceptibility. In order to characterize the localized deformation in slip channels and grain boundaries, parallel CERT experiments were also performed in an argon atmosphere. Results show that the IASCC susceptibility of the tested alloys increases with increasing irradiation dose and decreasing stacking fault energy. IASCC tends to initiate at locations where slip channels intersect grain boundaries. Localized deformation in the form of grain boundary sliding due to the ...

2008-12-01

494

K"A"T"P channels in mesenchymal stromal stem cells: Strong up-regulation of Kir6.2 subunits upon osteogenic differentiation  

British Library Electronic Table of Contents (United Kingdom)

The promising use of mesenchymal stromal cells (MSC) in regenerative technologies accounts for necessity of detailed study of their physiology. Proliferation and differentiation of multipotent cells often involve changes in their metabolic state. In the present study, we analyzed the expression of ATP-sensitive potassium (K"A"T"P) channels in MSC and upon in vitro differentiation. K"A"T"P channels are present in many cells and regulate a variety of cellular functions by coupling cell metabolism with membrane potential. Kir6.1, Kir6.2 and SUR2A were expressed in undifferentiated MSC, whereas SUR2B and SUR1 were not detected on cDNA and protein level. Upon adipogenic differentiation Kir6.1 and SUR2A showed a significant reduction of the amount of mRNA by 84% and 95%, respectively, whereas Ki...

2011-01-01

495

Influence of surface heat flux ratio on heat transfer augmentation in square channels with parallel, crossed, and V-shaped angled ribs  

Science.gov (United States)

The paper investigates the effect of the wall heat flux ratio on the local heat transfer augmentation in a square channel with two opposite in-line ribbed walls for Reynolds numbers from 15,000 to 80,000. The square channel composed of 10 isolated copper sections has a length-to-hydraulic diameter ratio of 20. The rib height-to-hydraulic diameter ratio is 0.0625 and the rib pitch-to-height ratio equals 10. Six ribbed side to smooth side wall heat flux ratios are studied for four rib orientations. The results show that the ribbed side wall heat transfer augmentation increases with increasing ribbed side to smooth side wall heat flux ratios, but the reverse is true for the smooth side wall heat transfer augmentation. The average heat transfer augmentation of the ribbed side and smooth side wall decreases slightly with increasing wall heat flux ratios. The effect of wall heat flux ratio reduces with increasing Reynolds numbers. The 60-deg V-shaped ...

1992-10-01

496

Influence of high energy electron irradiation on the characteristics of polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The influence of high energy electron (23 MeV) irradiation on the electrical characteristics of p-channel polysilicon thin film transistors (PSTFTs) was studied. The channel 220 nm thick LPCVD (low pressure chemical vapor deposition) deposited polysilicon layer was phosphorus doped by ion implantation. A 45 nm thick, thermally grown, SiO{sub 2} layer served as gate dielectric. A self-alignment technology for boron doping of the source and drain regions was used. 200 nm thick polysilicon film was deposited as a gate electrode. The obtained p-channel PSTFTs were irradiated with different high energy electron doses. Leakage currents through the gate oxide and transfer characteristics of the transistors were measured. A software model describing the field enhancement and the non-uniform current distribution at textured polysilicon/oxide interface was developed. In order to assess the irradiation-stimulated changes of gate oxide ...

2006-08-15

497

Influence of high energy electron irradiation on the characteristics of polysilicon thin film transistors  

International Nuclear Information System (INIS)

The influence of high energy electron (23 MeV) irradiation on the electrical characteristics of p-channel polysilicon thin film transistors (PSTFTs) was studied. The channel 220 nm thick LPCVD (low pressure chemical vapor deposition) deposited polysilicon layer was phosphorus doped by ion implantation. A 45 nm thick, thermally grown, SiO_2 layer served as gate dielectric. A self-alignment technology for boron doping of the source and drain regions was used. 200 nm thick polysilicon film was deposited as a gate electrode. The obtained p-channel PSTFTs were irradiated with different high energy electron doses. Leakage currents through the gate oxide and transfer characteristics of the transistors were measured. A software model describing the field enhancement and the non-uniform current distribution at textured polysilicon/oxide interface was developed. In order to assess the irradiation-stimulated changes of gate oxide ...

2006-08-01

498

Heat transfer augmentation in the transition region and low Reynolds number turbulent flows  

Energy Technology Data Exchange (ETDEWEB)

The authors report experimental results of heat transfer in the region of transition to turbulence. The augmentation was induced through deployment of periodically placed cylindrical eddy promoters in parallel plane channel flows. Eight different configurations were used. The presence of eddy promoters displaced the point of transition from Reynolds number values of 1500 for the plane channel to around 400 for the least stable case. The value of Nusselt number at the transition for eddy promoters cases was up to 2.5 times higher than the one for the plane channel at the transition. Furthermore, the lower the transition Reynolds number, the higher the Nusselt number at the transition. For the cases where the diameter of the promoters was small and/or the pitch large, the heat transfer results in the transition region were consistent with values obtained from the Reynolds analogy when the analogy was based on the mean ...

1995-12-31

499

Electronics for the Si detectors in APEX  

Energy Technology Data Exchange (ETDEWEB)

APEX (ATLAS Positron EXperiment), a collaborative effort of ANL, FSU, MSU/NSCL, Princeton, Queen`s, Rochester, Washington and Yale, is an experiment to study positron and electron production in very heavy ion collisions. The electrons and positrons are detected with two detector arrays, each consisting of 216 1 mm thick Si PIN diodes, and their energy and time-of-flight are measured. The number of detectors and limited space made it necessary to develop a system that could efficiently process and transfer signals from the detectors to the charge sensing ADC`s and data readout electronics as well as monitor the condition of the detectors. The discussion will cover the electronics designed for the Si detectors, including the charge amplifier, ``Mother board`` for the charge amplifiers, 8 channel Shaper, 16 channel Constant Fraction Discriminator (CFD), 16 channel Peak-to-FERA (PTF) and the integration of the CFD and PTF with ...

1994-07-01

500

Distributed STBCs with Partial Interference Cancellation Decoding  

CERN Document Server

Recently, Guo and Xia introduced low complexity decoders called Partial Interference Cancellation (PIC) and PIC with Successive Interference Cancellation (PIC-SIC), which include the Zero Forcing (ZF) and ZF-SIC receivers as special cases, for point-to-point MIMO channels. In this paper, we show that PIC and PIC-SIC decoders are capable of achieving the full cooperative diversity available in wireless relay networks. We give sufficient conditions for a Distributed Space-Time Block Code (DSTBC) to achieve full diversity with PIC and PIC-SIC decoders and construct a new class of DSTBCs with low complexity full-diversity PIC-SIC decoding. We also show that almost all known full-diversity PIC/PIC-SIC decodable codes constructed for point-to-point MIMO channels can be used as full-diversity PIC/PIC-SIC decodable DSTBCs in relay networks. The proposed DSTBCs with low complexity, full-diversity PIC/PIC-SIC decoding achieve higher rates (in complex ...

2010-01-01