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81.
Ken Maynard Patrick Moss Marcus Whitehead S. Narayanan Matt Garay Nathan Brannon Raj Gopal Kantamneni & Todd Kustra 《Expert Systems》2001,18(2):88-98
Although developments on software agents have led to useful applications in automation of routine tasks such as electronic mail filtering, there is a scarcity of research that empirically evaluates the performance of a software agent versus that of a human reasoner, whose problem-solving capabilities the agent embodies. In the context of a game of a chance, namely Yahtzee©, we identified strategies deployed by expert human reasoners and developed a decision tree for agent development. This paper describes the computer implementation of the Yahtzee game as well as the software agent. It also presents a comparison of the performance of humans versus an automated agent. Results indicate that, in this context, the software agent embodies human expertise at a high level of fidelity. 相似文献
82.
beta3GalTs are type II transmembrane proteins that transfer galactose from UDP-Gal donor substrate to acceptor GlcNAc, GalNAc or Gal in beta1-->3-linkage. beta1-->3-linked galactose have been found to be a part of many glycans like glycosphingolipids, core tetrasaccharide of proteoglycans, type 1 chains. The 3-D structure of none of the beta3GalTs is known to date. In this study, the 3-D structures of human beta3GalT I, II, IV, V, VI and beta3GalNAcT I have been modeled using fold-recognition and comparative modeling methods. Residues that constitute the UDP-Gal binding site have been predicted. The models are able to qualitatively rationalize data from the site-directed mutagenesis experiments reported in the literature. Residues likely to be involved in conferring differential acceptor substrate specificity have been predicted by a combination of specificity determining positions prediction (SDPs) and subsequent mapping on the generated 3-D models. 相似文献
83.
Refolding of staphylococcal nuclease has been studied recently by hydrogen-deuterium exchange and NMR spectroscopy. These studies infer that beta-hairpin formed by strand 2 and strand 3 connected by reverse turn forms early during the refolding of nuclease. Typically, hydrogen-deuterium exchange NMR techniques are usually carried out on a time scale of milliseconds whereas beta-hairpins are known to fold on a much shorter time scale. It follows that in the experiments, the hydrogen-deuterium exchange protection patterns could be arising from a significant population of fully formed hairpins. In order to demonstrate it is the fully formed hairpins which gives rise to the hydrogen-deuterium exchange protection patterns, we have considered molecular dynamics simulation of the peptide (21)DTVKLMYKGQPMTFR(35) from staphylococcal nuclease corresponding to the beta-hairpin region, using GROMOS96 force field under NVT conditions. Starting from unfolded conformational states, the peptide folds into hairpin conformations with native-like and non-native hydrogen bonding patterns. Subsequent to folding, equilibrium conditions prevail. The computed protection factors and atom depth values, at equilibrium, of the various amide protons agree qualitatively with experimental observations. A collection of molecules following the trajectories observed in the simulations can account for experimental observations. These simulations provide a molecular picture of the formed hairpins and their conformational features during the refolding experiments on nuclease, monitored by hydrogen-deuterium exchange. 相似文献
84.
A new iterative technique to reduce the ringing artifacts in chemical shift images due to the truncation of the high spatial frequency is presented. In this approach the authors extrapolate the high spatial frequency data guided by the edge information obtained from a high resolution anatomic image of the region of interest. The fact that the edge information obtained from the anatomic image can be off by a few pixels (due to factors such as chemical shift artifact, error in edge detection or misregistration) is taken into account by assuming a confidence interval of several pixels around the anatomic edges. The algorithm is validated on simulated and in vivo data, and excellent results were obtained. 相似文献
85.
This paper examines some of the special considerations which apply to the development of such software for minicomputers. These are treated under the following general categories:
- loading and throughput
- the external interfaces of the system software
- the internal structure of the system software
- developing the software
86.
Nanoclays for polymer nanocomposites, paints, inks, greases and cosmetics formulations, drug delivery vehicle and waste water treatment 总被引:2,自引:0,他引:2
Hasmukh A. Patel Rajesh S. Somani Hari C. Bajaj Raksh V. Jasra 《Bulletin of Materials Science》2006,29(2):133-145
An overview of nanoclays or organically modified layered silicates (organoclays) is presented with emphasis placed on the
use of nanoclays as the reinforcement phase in polymer matrices for preparation of polymer/layered silicates nanocomposites,
rheological modifier for paints, inks and greases, drug delivery vehicle for controlled release of therapeutic agents, and
nanoclays for industrial waste water as well as potable water treatment to make further step into green environment. A little
amount of nanoclay can alter the entire properties of polymers, paints, inks and greases to a great extent by dispersing 1nm
thick layered silicate throughout the matrices. The flexibility of interlayer spacing of layered silicates accommodates therapeutic
agents which can later on be released to damaged cell. Because the release of drugs in drug-intercalated layered materials
is controllable, these new materials have a great potential as a delivery host in the pharmaceutical field. The problem of
clean water can be solved by treating industrial and municipal waste water with organoclays in combination with other sorbents
like activated carbon and alum. Organoclays have proven to be superior to any other water treatment technology in applications
where the water to be treated contains substantial amounts of oil and grease or humic acid. 相似文献
87.
Shuangqun Zhao Xishan Xie Gaylord D. Smith Shailesh J. Patel 《Materials & Design》2006,27(10):1120-1127
INCONEL alloy 740 is a newly developed Ni–Cr–Co–Mo–Nb–Ti–Al superalloy in the application to ultra-supercritical boilers with steam temperatures up to 700 °C. By means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), micro-chemical phase analyses, and corrosion-resisting test, this paper investigates the structure stability of the alloy at elevated temperature and concentrates on coal ash corrosion performance of the alloy under the simulated coal ash/flue gas condition. Experimental results show that the most important structure instabilities of the alloy during prolonged aging are γ′ coarsening, γ′ to η transformation and G phase formation at grain boundary. The performance of corrosion resistance of the alloy would meet the requirement of ultra-supercritical boiler tubes. The phase computation by means of Thermo-Calc has been adopted in chemical composition modification for structure stability improvement. Two suggested new modified alloys in adjustment of the Al and Ti contents and in control of Si level, and also in maintenance of Cr content of the alloy were designed and melted for experimental investigation. These two modified alloys exhibit more stable microstructure during 760 °C long time aging. 相似文献
88.
F. Abdollahi H.A. Talebi R.V. Patel 《Mechatronics, IEEE/ASME Transactions on》2006,11(4):488-495
This paper presents an approach for stable identification of multivariable nonlinear system dynamics using a multilayer feedforward neural network. Unlike most of the previous neural network identifiers, the proposed identifier is based on a nonlinear-in-parameters neural network (NLPNN). Therefore, it is applicable to systems with higher degrees of nonlinearities. Both parallel and series-parallel models are used with no a priori knowledge about the system dynamics. The method can be considered both as an online identifier that can be used as a basis for designing a neural network controller as well as an offline learning scheme for monitoring the system states. A novel approach is proposed for the weight updating mechanism based on the modification of the backpropagation (BP) algorithm. The stability of the overall system is shown using Lyapunov's direct method. To demonstrate the performance of the proposed algorithm, an experimental setup consisting of a three-link macro-micro manipulator (M/sup 3/) is considered. The proposed approach is applied to identify the dynamics of the experimental robot. Experimental and simulation results are given to show the effectiveness of the proposed learning scheme. 相似文献
89.
C. Ji N. Chubun R.G. Broeke J. Cao Y. Du S.J.B. Yoo K.Y. Liou J.R. Lothian S. Vatanapradit S.N.G. Chu B. Patel W.S. Hobson W.T. Tsang 《Photonics Technology Letters, IEEE》2006,18(4):625-627
We report a 10-GHz colliding pulse mode-locked laser fabricated with integrated active-passive waveguides. The laser fabrication adopted a deep reactive ion etching and single-step metal-organic vapor phase epitaxy regrowth process for forming the buried heterostructure waveguide. Clean output pulses resulted from laterally tilting the active-passive interface and effectively suppressing residual back-reflections at the interface. Hybrid mode-locking resulted in a synchronized transform-limited sech/sup 2/optical waveform. Pulsewidth, chirp, timing jitter, and frequency-locking range were investigated through systematic device biasing condition optimization. 相似文献
90.
K. K. Makhija Arabinda Ray R. M. Patel U. B. Trivedi H. N. Kapse 《Bulletin of Materials Science》2005,28(1):9-17
A sensor for ammonia gas and ethanol vapour has been fabricated using indium oxide thin film as sensing layer and indium tin
oxide thin film encapsulated in poly(methyl methacrylate) (PMMA) as a miniature heater. For the fabrication of miniature heater
indium tin oxide thin film was grown on special high temperature corning glass substrate by flash evaporation method. Gold
was deposited on the film using thermal evaporation technique under high vacuum. The film was then annealed at 700 K for an
hour. The thermocouple attached on sensing surface measures the appropriate operating temperature.
The thin film gas sensor for ammonia was operated at different concentrations in the temperature range 323–493 K. At 473 K
the sensitivity of the sensor was found to be saturate. The detrimental effect of humidity on ammonia sensing is removed by
intermittent periodic heating of the sensor at the two temperatures 323K and 448 K, respectively. The indium oxide ethanol
vapour sensor operated at fixed concentration of 400 ppm in the temperature range 293–393 K. Above 373 K, the sensor conductance
was found to be saturate. With various thicknesses from 150–300 nm of indium oxide sensor there was no variation in the sensitivity
measurements of ethanol vapour. The block diagram of circuits for detecting the ammonia gas and ethanol vapour has been included
in this paper. 相似文献