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1.
Response time (RT) curves were obtained from Ss who were instructed to search for following or preceding letters in the alphabet with respect to given stimulus letters. To describe the shape of these curves, D. Klahr et al (see record 1984-05777-001) proposed a search model. It was assumed that the alphabet was internally represented by a number of chunks of a few letters. Klahr et al assumed that serial searches occurred along 2 hierarchical levels: (1) a search for the correct chunk and (2) a search of the letters within the chunk. The Klahr et al model predicted an ascending sawtooth-shaped RT curve. However, according to the authors' analysis of the data, the RT curves did not show the expected sawtooth shapes. In order to find out whether the lack of empirical support for the model was an artifact of averaging the data, the experiment was replicated. It was found that individual RT curves did not show the shape characteristics that were predicted by the Klahr et al model either. The data supported the hypothesis that the access of letters was direct without any hierarchy, and that the retrieval of successive letters was determined by the variable associations between subsequent letters. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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本文报导用于异丁烯(叔丁醇)选择氧化制MAL(甲基丙烯醛)的多元复合氧化物催化剂的研究结果。同共沉淀法制备的催化剂的活性主要决定于其化学组成,同时受到制备条件的影响。最佳催化剂的主要物相组成为PbO3,Bi2MoO3.3、NiMoO4、Sb2O3及a-Fe2O3小颗粒。在355℃,1000~2500h-1空速范围,叔丁醇:水:空气=1:3.3:7(摩尔比)的条件下可获得异丁烯转化率达96%,MAL选择性达89%的结果。  相似文献   
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A study of the high-alkali region of glass formation in the system Na2O +B2O3 reveals that retention of CO2 from carbonate starting materials can become a serious preparative problem at the high-alkali extreme. Results presented for glasses prepared using both Na2O and Na2CO3 show that residual CO2 can lead to major differences in physical properties which in this work are represented by the viscosity-related glass transition temperature .  相似文献   
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车载悬架性能检测与可调阻尼减震器   总被引:2,自引:0,他引:2  
刘文强  王磊  谢伟东 《机床与液压》2003,(3):278-279,296
本文采用模糊控制理论,论述了基于被动悬架性能测试基础上的阻尼调节技术,建立了1/4车被动悬架的检测判别理论模型,进行了模拟计算分析,仿真表明,能够提高车辆的安全性,同时,为设计制造性能可靠高效的可调阻尼悬架系统打下良好基础。  相似文献   
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This paper presents a new approach to make current and future television universally accessible. The proposed approach provides a means of universal accessibility both for remotely operating the TV set and for interacting with online services delivered through the TV. This proposal is based on the ISO/IEC 24752 “Universal Remote Console” (URC) standard. This standard defines an abstract user interface layer called the “user interface socket” and allows the development of pluggable (plug-in) user interfaces for any type of user and any control device. The proposed approach lays the foundation for the development of advanced user interfaces that can be interacted within various modalities. Different prototypes have been developed based on this approach and tested with end users. The user tests have shown this approach to be a viable option for the proposed scenarios. Based on the experience gathered with the prototypes, recommendations and implementation options are suggested for commercial adoption.  相似文献   
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Materials with controllable multifunctional abilities for optical imaging (OI) and magnetic resonant imaging (MRI) that also can be used in photodynamic therapy are very interesting for future applications. Mesoporous TiO2 sub‐micrometer particles are doped with gadolinium to improve photoluminescence functionality and spin relaxation for MRI, with the added benefit of enhanced generation of reactive oxygen species (ROS). The Gd‐doped TiO2 exhibits red emission at 637 nm that is beneficial for OI and significantly improves MRI relaxation times, with a beneficial decrease in spin–lattice and spin–spin relaxation times. Density functional theory calculations show that Gd3+ ions introduce impurity energy levels inside the bandgap of anatase TiO2, and also create dipoles that are beneficial for charge separation and decreased electron–hole recombination in the doped lattice. The Gd‐doped TiO2 nanobeads (NBs) show enhanced ability for ROS monitored via ?OH radical photogeneration, in comparison with undoped TiO2 nanobeads and TiO2 P25, for Gd‐doping up to 10%. Cellular internalization and biocompatibility of TiO2@x Gd NBs are tested in vitro on MG‐63 human osteosarcoma cells, showing full biocompatibility. After photoactivation of the particles, anticancer trace by means of ROS photogeneration is observed just after 3 min irradiation.  相似文献   
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Diode-Pumped Solid-State Lasers for Inertial Fusion Energy   总被引:5,自引:0,他引:5  
We have begun building the Mercury laser system as the first in a series of new generation diode-pumped solid-state lasers for inertial fusion research. Mercury will integrate three key technologies: diodes, crystals, and gas cooling, within a unique laser architecture that is scalable to kilojoule and megajoule energy levels for fusion energy applications. The primary near-term performance goals include 10% electrical efficiencies at 10 Hz and 100J with a 2–10 ns pulse length at 1.047 m wavelength. When completed, Mercury will allow rep-rated target experiments with multiple chambers for high energy density physics research.  相似文献   
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Continuous-time quantum Monte Carlo impurity solvers are algorithms that sample the partition function of an impurity model using diagrammatic Monte Carlo techniques. The present paper describes codes that implement the interaction expansion algorithm originally developed by Rubtsov, Savkin, and Lichtenstein, as well as the hybridization expansion method developed by Werner, Millis, Troyer, et al. These impurity solvers are part of the ALPS-DMFT application package and are accompanied by an implementation of dynamical mean-field self-consistency equations for (single orbital single site) dynamical mean-field problems with arbitrary densities of states.

Program summary

Program title: dmftCatalogue identifier: AEIL_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIL_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: ALPS LIBRARY LICENSE version 1.1No. of lines in distributed program, including test data, etc.: 899 806No. of bytes in distributed program, including test data, etc.: 32 153 916Distribution format: tar.gzProgramming language: C++Operating system: The ALPS libraries have been tested on the following platforms and compilers:
  • • 
    Linux with GNU Compiler Collection (g++ version 3.1 and higher), and Intel C++ Compiler (icc version 7.0 and higher)
  • • 
    MacOS X with GNU Compiler (g++ Apple-version 3.1, 3.3 and 4.0)
  • • 
    IBM AIX with Visual Age C++ (xlC version 6.0) and GNU (g++ version 3.1 and higher) compilers
  • • 
    Compaq Tru64 UNIX with Compq C++ Compiler (cxx)
  • • 
    SGI IRIX with MIPSpro C++ Compiler (CC)
  • • 
    HP-UX with HP C++ Compiler (aCC)
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    Windows with Cygwin or coLinux platforms and GNU Compiler Collection (g++ version 3.1 and higher)
RAM: 10 MB–1 GBClassification: 7.3External routines: ALPS [1], BLAS/LAPACK, HDF5Nature of problem: (See [2].) Quantum impurity models describe an atom or molecule embedded in a host material with which it can exchange electrons. They are basic to nanoscience as representations of quantum dots and molecular conductors and play an increasingly important role in the theory of “correlated electron” materials as auxiliary problems whose solution gives the “dynamical mean field” approximation to the self-energy and local correlation functions.Solution method: Quantum impurity models require a method of solution which provides access to both high and low energy scales and is effective for wide classes of physically realistic models. The continuous-time quantum Monte Carlo algorithms for which we present implementations here meet this challenge. Continuous-time quantum impurity methods are based on partition function expansions of quantum impurity models that are stochastically sampled to all orders using diagrammatic quantum Monte Carlo techniques. For a review of quantum impurity models and their applications and of continuous-time quantum Monte Carlo methods for impurity models we refer the reader to [2].Additional comments: Use of dmft requires citation of this paper. Use of any ALPS program requires citation of the ALPS [1] paper.Running time: 60 s–8 h per iteration.References:
  • [1] 
    A. Albuquerque, F. Alet, P. Corboz, et al., J. Magn. Magn. Mater. 310 (2007) 1187.
  • [2] 
    http://arxiv.org/abs/1012.4474, Rev. Mod. Phys., in press.
  相似文献   
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