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Kunkel Mark A.; Hector Mark A.; Góngora Coronado Elías; Castillo Vales Victor 《Canadian Metallurgical Quarterly》1989,36(3):322
Conducted a study of client expectations of psychological services in Yucatán, Mexico, under the sponsorship of a grant from the Organization of American States. The Expectations about Counseling–Brief form (EAC-B) questionnaire was translated and administered to 488 subjects across age, sex, and experience with psychological services. Subsequent analyses supported the reliability and robustness of the Spanish EAC-B, with factor structure similar to the EAC-B in English. Some relation was found among age, sex, prior counseling experience, and expectations about counseling. Implications of these data for future research and comparison with U.S. subjects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The TSIMMIS Approach to Mediation: Data Models and Languages 总被引:18,自引:2,他引:16
Hector Garcia-Molina Yannis Papakonstantinou Dallan Quass Anand Rajaraman Yehoshua Sagiv Jeffrey Ullman Vasilis Vassalos Jennifer Widom 《Journal of Intelligent Information Systems》1997,8(2):117-132
TSIMMIS—The Stanford-IBM Manager of Multiple InformationSources—is a system for integrating information. It offers a datamodel and a common query language that are designed to support thecombining of information from many different sources. It also offerstools for generating automatically the components that are needed tobuild systems for integrating information. In this paper we shalldiscuss the principal architectural features and their rationale. 相似文献
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Abstract. Outliers in time series seriously affect conventional parameter estimates. In this paper a robust recursive estimation procedure for the parameters of auto-regressve moving-average models with additive outliers is proposed. Using 'cleaned' residuals from an initial robust fit of an autoregression of high order as input, bounded influence regression is applied recursively. The proposal follows certain ideas of Hannan and Rissanen, who suggested a three-stage procedure for order and parameter estimation in a conventional setting.
A Monte Carlo study is performed to investigate the robustness properties of the proposed class of estimates and to compare them with various other suggestions, including least squares, M estimates, residual autocovariance and truncated residual autocovariance estimates. The results show that the recursive generalized M estimates compare favourably with them. Finally, possible modifications to master even vigourous situations are suggested. 相似文献
A Monte Carlo study is performed to investigate the robustness properties of the proposed class of estimates and to compare them with various other suggestions, including least squares, M estimates, residual autocovariance and truncated residual autocovariance estimates. The results show that the recursive generalized M estimates compare favourably with them. Finally, possible modifications to master even vigourous situations are suggested. 相似文献
6.
Michael P. Balogh Camille Y. Jones J.F. Herbst Louis G. Hector Jr. Matthew Kundrat 《Journal of Alloys and Compounds》2006,420(1-2):326-336
Half-Heusler compounds of Sn-doped TiCoSb “TiCoSnxSb1−x (x = 0.0, 0.01, and 0.05)” were prepared and their thermoelectric properties were measured above room temperature. From the EDX analysis, all the samples have three phases: the TiCoSnxSb1−x, Co-rich, and Ti-rich phases. The values of the thermoelectric power increase with Sn doping, and a positive thermoelectric power is obtained in the sample of TiCoSn0.05Sb0.95. The thermal conductivity decreases both with increasing temperature and with Sn content. The maximum value of ZT for p-type material is 0.030 at 988 K in the sample of TiCoSn0.05Sb0.95. 相似文献
7.
K. V. Sudhakar J. C. Cisneros Hector Cervantes Cosme Gomez Pineda 《Journal of Materials Engineering and Performance》2006,15(1):117-121
The technology of materials removal is improved greatly by the introduction of advanced cutting tools like cubic boron nitride,
ceramics, polycrystalline diamond and the more recent whisker-reinforced materials. In this paper, the influence of cutting
temperature on machinability, mechanical properties, microstructure, and fracture morphology of Cu-2Be alloy using a polycrystalline
diamond cutter is investigated. The information on machining, microstructure, and fracture morphology of Cu-2Be alloy are
very useful to understand their fabrication characteristics and the basic mechanisms of its deformation and fracture. The
machinability (in terms of surface finish) of Cu-2Be alloy is evaluated as a function of cutting temperature, resulting from
wet and dry cutting. Machining is carried out on a Hardinge Cobra 42 CNC machine (Hardinge Inc., Elmira, NY), and the machining
parameters used—cutting speed, depth of cut, and feed rate—are kept constant during both wet and dry cutting. The machined
surface finish on Cu-2Be alloy is measured using a surface finish analyzer (Surftest 401, series 178) technique. The machined
specimens are examined for their strength and hardness properties using a standard Universal Testing Machine and Rockwell
hardness tester, respectively. Wet cutting (using coolants) produced a smooth surface finish when compared with dry cutting
of the Cu-2Be alloy. The machined specimens are examined for their microstructural features using a Nikon optical microscope.
The specimens are etched using a suitable etchant solution for revealing such microstructure constituents as grain size, phase
proportions, and the possible overheated areas (especially in dry cutting). The fractured surfaces from the tensile and impact
toughness tests are investigated for their fracture morphologies (dry and wet cutting) using a microprocessor-controlled scanning
electron microscope (Jeol Model JSM 5910 LV). A detailed analysis is also made to understand and interpret the basic fracture
mechanisms responsible for crack initiation and crack propagation. The Cu-2Be alloy showed relatively higher mechanical properties
in wet cutting in comparison to dry cutting operations. Fracture studies demonstrated intergranular and ductile fractures
as dominant modes of fracture mechanisms in Cu-2Be alloy. 相似文献
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9.
Adrian Hernandez-Becerril Mariko Nakano-Miyatake Marco Ramirez-Tachiquin Hector Perez-Meana 《通讯和计算机》2013,(5):649-660
Recently, a multisecret sharing scheme for secret color images among a set of users was proposed, which allows that each participant to share secret color images with the rest of participants in such way that all of them can recover all secret color images only if all participants pool their shares. In this work a parallel implementation of the cellular automata-based multisecret sharing scheme is proposed, in which the technology of CUDA (Compute Unified Device Architecture) is used in parallelization, taking advantage that each cell of cellular automata can be processed independently. The processing time of the proposed scheme is analyzed and it is proved that the proposed parallel algorithm using the CUDA structure is more than 12 times faster than the conventional sequential algorithm. This reduction of temporal complexity allows the practical use of the secret sharing scheme in many information security fields. 相似文献
10.
Hector Archila Sebastian Kaminski David Trujillo Edwin Zea Escamilla Kent A. Harries 《Materials and Structures》2018,51(4):102
The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or round strips) has often been proposed as an alternative to relatively expensive reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost—bamboo is readily available in many tropical and sub-tropical locations, whereas steel reinforcement is relatively more expensive—and more recently, the drive to find more sustainable alternatives in the construction industry. This review addresses such ‘bamboo-reinforced concrete’ and assesses its structural and environmental performance as an alternative to steel reinforced concrete. A prototype three bay portal frame, that would not be uncommon in regions of the world where bamboo-reinforced concrete may be considered, is used to illustrate bamboo reinforced concrete design and as a basis for a life cycle assessment of the same. The authors conclude that, although bamboo is a material with extraordinary mechanical properties, its use in bamboo-reinforced concrete is an ill-considered concept, having significant durability, strength and stiffness issues, and does not meet the environmentally friendly credentials often attributed to it. 相似文献