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41.
42.
Memorializes B?rbel Inhelder, who is noted for her participation in the creation of a new discipline, genetic epistemology (GE). Inhelder's work comprised at least 3 main pioneering efforts: (1) the construction of GE, including books on the topics of the development of elementary logical structures, the child's representation of space and spontaneous geometry, the development of the idea of chance, mental imagery, memory, and learning; (2) the extension of GE to the study of adolescent cognitive development, which led her to recognition of formal operations as a stage typically appearing in adolescent thought; and (3) the connection of the study and understanding of mental retardation with the emerging field of cognitive development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
R. Gruber Ch. Pfersisch S. Semenzato F. Troyon T. Tsunematsu 《Computer Physics Communications》1981,24(3-4):381-387
The various problems that are encountered in searching with ERATO the limits of stability of axisymmetric toroidal equilibria are described and illustrated with specific examples. 相似文献
44.
Niederkofler EE Tubbs KA Gruber K Nedelkov D Kiernan UA Williams P Nelson RW 《Analytical chemistry》2001,73(14):3294-3299
A high-throughput mass spectrometric immunoassay (MSIA) system for the analysis of proteins directly from biological fluids is reported. A 96-well-format robotic workstation equipped with antibody-derivatized affinity pipet tips was used for the parallel extraction of specific proteins from samples and subsequent deposition onto 96-well arrayed matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) targets. Interferences from nonspecifically bound proteins were minimized through choice of appropriate affinity pipet tip derivatization chemistries. Sample preparation for MALDI-TOFMS was enhanced through the use of hydrophobic/hydrophilic contrasting targets, which also presented functionalities found to promote matrix/analyte crystal growth. Automated mass spectrometry was used in the unattended acquisition of data, resulting in an analysis rate of approximately 100 samples/h (biological fluid-->data). The quantitative MSIA of beta2m levels present in human plasma samples is given as illustration. 相似文献
45.
Diffractive optical elements as raster-image generators 总被引:1,自引:0,他引:1
Gruber M 《Applied optics》2001,40(32):5830-5839
The use of diffractive optical elements (DOEs) to generate complex raster images for a primarily artistic purpose is dealt with. Aspects of human vision that are relevant for the design of such elements are discussed. A design method based on an iterative Fourier transform algorithm and extended with elements from the direct-binary-search and the simulated-annealing algorithms is described. The proposed method provides a large set of parameters that can be adjusted freely to optimize it for any given design task. For demonstration a phase-only DOE was designed that generates an image of a Chinese dragon as a diffraction pattern. It was realized as a surface-relief element on a planar substrate through multilevel binary lithography and reactive-ion etching. Experimental tests confirm the usefulness of the design and the fabrication procedures to achieve excellent image quality. 相似文献
46.
Stephane Neuville 《Thin solid films》2007,515(17):6619-6653
Hard carbon coatings hold the key to improved performance for many types of products. However the achievement of these improvements requires the selection of the appropriate type of carbon coating and therefore the correct process and appropriate deposition parameters. The huge range of properties achievable in carbon coatings is mainly due to the ability of carbon to form different types of interatomic bonds, to take up different sites, and to adopt different structures. In addition to intrinsic material properties, other factors must also be considered for each application, such as the adhesion level achievable and coating cost. This complex situation explains why the number of applications for hard carbon films is still more limited than originally expected. Despite the considerable progress achieved during the last decade in hard coating technologies, practical results often appear conflicting, with differences in properties occurring even within the same types of coatings. Furthermore, the many different deposition systems and processes which have been developed introduce further complications in regard to (for example) achievable coating uniformity and deposition rates. Thus, there is often confusion in the use of certain fundamental principles, especially regarding the growth mechanisms and the effects which produce more dense homogeneous and stable coating materials. This is especially true for the improved properties of tetrahedral amorphous carbon films, which are different from previously reported diamond-like carbon materials, and can be created by adapting and improving existing industrial processes, to offer advantages compared to earlier coatings, and hence possibilities for important new applications. This paper discusses issues relating to intrinsic material properties, and practical aspects such as adhesion, to provide a framework for the development, selection and use of hard carbon coatings in practical situations. 相似文献
47.
Ayoub Moradi Laurent Metivier Olivier de Viron Stephane Calmant Catherine Mering 《International journal of remote sensing》2013,34(16):6060-6075
Moderate-Resolution Imaging Spectroradiometer (MODIS) optical and infrared data are used to monitor changes in the Caspian Sea coastline. The information extracted from MODIS images is converted into total water volume and mean lake level by combining a digital elevation model (DEM) with remote-sensing data. The elevation estimates were enhanced by reprocessing the MODIS data at the sub-pixel scale. The water volume variations estimated from MODIS data along with DEM are compared to other estimations derived from altimetry data sets, and show fair agreement. 相似文献
48.
The refractory lining in steel ladles is exposed to chemical and mechanical loads during the heats. Mechanical loads develop from the thermal expansion of the refractories which is confined either by the steel construction or by regions of different temperature within the refractory material. The aim of this work was the investigation of factors influencing the mechanical durability of refractory steel ladle linings and the clarification of failure mechanisms. Especially irreversible strains at the hot face of the working lining caused by compressive stresses induce an opening of joints at the hot face. The irreversible strains reduce the compressive stresses in circumferential direction and increase the probability of tensile failure. A further effect of the irreversible strains is a reduced stability of the working lining. Of special interest in this context is a possible controlled expansion of bricks to counterbalance the irreversible compressive strains. 相似文献
49.
George H. Neilson Jr. Benjamin A. Carreras Daniel A. D'Ippolito Otto Gruber Mitsuru Kikuchi Kevin McGuire Douglass E. Post James D. Callen Patrick H. Diamond Kenneth W. Gentle E. Bickford Hooper Earl S. Marmar Cynthia Kieras Phillips Tony S. Taylor 《Journal of Fusion Energy》1999,18(3):117-160
This is the May 1996 report of a subpanel of the US Department of Energy Fusion Energy Sciences Advisory Committee (FESAC), charged with conducting a review of the progress, priorities and potential near-term contributions of TFTR, DIII-D and Alcator C-MOD (and other facilities as appropriate) as part of the transition to a Fusion Energy Sciences Program and produce an optimum plan for obtaining the most scientific benefit from them. 相似文献
50.