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1.
2.
T. M. Holden J. W. L. Pang R. A. Holt 《Metallurgical and Materials Transactions A》2002,33(3):749-755
The development of the understanding of the intergranular stresses in ZIRCALOY-2 is reviewed. Neutron diffraction measurements
of the intergranular strains were made on rod-textured material and highly textured plate. The elastoplastic self-consistent
(EPSC) model provides a sound theoretical foundation for our understanding of the behavior. The strain response of ZIRCALOY-2
to applied tensile stress is well described for two very different textures with the same slip and hardening parameters. It
is almost certain that tensile twinning is the explanation for the response to compressive stress and rolling that is, as
yet, incompletely understood.
This article is based on a presentation made in the symposium entitled “Defect Properties and Mechanical Behavior of HCP Metals
and Alloys” at the TMS Annual Meeting, February 11–15, 2001, in New Orleans, Louisiana, under the auspices of the following
ASM committees: Materials Science Critical Technology Sector, Structural Materials Division, Electronic, Magnetic & Photonic
Materials Division, Chemistry & Physics of Materials Committee, Joint Nuclear Materials Committee, and Titanium Committee. 相似文献
3.
Mary J. Garson Mary P. Zimmermann Christopher N. Battershill Janet L. Holden Peter T. Murphy 《Lipids》1994,29(7):509-516
The tropical marine spongeAmphimedon terpenensis (family Niphatidae, order Haplosclerida) has previously been shown to possess unusual lipids, including unusual fatty acids.
The biosynthetic origin of these fatty acids is of interest as the sponge supports a significant population of eubacterial
and cyanobacterial symbionts. The total fatty acid composition of the sponge was analyzed by gas chromatography/mass spectrometry
of the methyl esters. Among the most abundant of the fatty acids in intact tissue were 16∶0, 18∶0 and 3,7,11,15-tetramethylhexadecanoic
(phytanic) acid. In addition, three brominated fatty acids, (5E,9Z)-6-bromo-5,9-tetracosadienoic acid (24∶2Br), (5E,9Z)-6-bromo-5,9-pentacosadienoic acid (25∶2Br) and (5E,9Z)-6-bromo-5,9-hexacosadienoic acid (26∶2Br) were also present. The three brominated fatty acids, together with phytanic acid,
were isolated from both ectosomoal (superficial) and choanosomal (internal) regions of the sponge. Analysis of extracts prepared
from sponge/symbiont cells, partitioned by density gradient centrifugation on Ficoll, indicated that phytanic acid and the
three brominated fatty acids were associated with sponge cells only. Further, a fatty acid methyl ester sample from intact
tissue ofA. terpenensis was partitioned according to phospholipid class, and the brominated fatty acids were shown to be associated with the phosphatidylserine
and phosphatidylethanolamine fractions that are commonly present in marine sponge lipids. The phosphatidylcholine and phosphatidylglycerol
fractions were rich in the relatively shorter chain fatty acids (16∶0 and 18∶0). The association of brominated long-chain
fatty acids (LCFA) with sponge cells has been confirmed. The findings allow comment on the use of fatty acid profiles in chemotaxonomy
and permit further interpretation of LCFA biosynthetic pathways in sponges. The assignment of the sponge studied, which is
currently placed asA. terpenensis, is being supported to some extent, but the species is unusual in having C25 fatty acids as the major constituent in this group. Other factors, such as season or microenvironmental conditions, may influence
observed fatty acid composition which tends to reduce the usefulness of fatty acid profiles as markers in sponge chemotaxonomy. 相似文献
4.
Holden Ronald R.; Woermke Christina; Fekken G. Cynthia 《Canadian Metallurgical Quarterly》1993,25(1):1
Evaluated the effects of increasing scale reliability and of priming dimensional activation on the construct validity of personality test item differential response latencies. 93 undergraduates were computer-administered items from the 3 lengthened scales of the Personality Research Form. Findings show that differential response latencies can demonstrate remarkably strong evidence for their construct validity. In addition, the priming of personality traits may enhance the construct validity of their corresponding differential response latencies. Results support a model of test item responding where differential item response latencies reflect the interaction of an individual's schema with test item content. (French abstract) (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
5.
Disguise and the structured self-report assessment of psychopathology: I. An analogue investigation.
Explored the utility of disguise in structured self-report assessments of psychopathology in 3 experiments with 370 university students. Exp I used items from the Basic Personality Inventory (BPI); Exp II used the BPI, the Desirability scale of the Personality Research Form—Form E, and 4 criterion measures; and Exp III used 2 of the criterion measures and the BPI. Data indicate that under normal test-taking circumstances, the use of disguised test items was not advantageous. This relationship, however, was moderated by a number of dimensional parameters. When faking response sets in terms of desirability was induced, the use of disguised test item content was not useful. Data are interpreted in terms of the various strategies of test construction underlying the assessment of psychopathology. Results support a rational strategy of test construction emphasizing the use of relevant test item content. It is concluded that, in structured self-report assessments, the most valid results may be obtained through the use of direct questions with cooperative test respondents. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Dunham M.E. Light M. Holden D.N. 《Antennas and Propagation, IEEE Transactions on》1995,43(10):1017-1021
Helical antennas are popular and well characterized for CW frequency domain performance. Renewed interest in time-domain applications of electromagnetics, such as impulse radar, makes accurate time-domain data on broad-band antennas desirable. Although the principal endfire helix radiation mode has been extensively studied in the frequency domain, other modes important in pulse operation are poorly characterized, making a total Fourier transform approach difficult. We have performed impulse tests on helices with two to five turns, establishing novel features of the response and confirming some aspects of frequency domain data. Quick comparisons to time and frequency-domain modeling codes indicate good correspondence of gross features. Successful octave band-pulse operation was achieved, and a few features of helix pulse response invite further investigation 相似文献
7.
Automatic registration of multi-source remote-sensing images is a difficult task as it must deal with the varying illuminations and resolutions of the images, different perspectives and the local deformations within the images. This paper proposes a fully automatic and fast non-rigid image registration technique that addresses those issues. The proposed technique performs a pre-registration process that coarsely aligns the input image to the reference image by automatically detecting their matching points by using the scale invariant feature transform (SIFT) method and an affine transformation model. Once the coarse registration is completed, it performs a fine-scale registration process based on a piecewise linear transformation technique using feature points that are detected by the Harris corner detector. The registration process firstly finds in succession, tie point pairs between the input and the reference image by detecting Harris corners and applying a cross-matching strategy based on a wavelet pyramid for a fast search speed. Tie point pairs with large errors are pruned by an error-checking step. The input image is then rectified by using triangulated irregular networks (TINs) to deal with irregular local deformations caused by the fluctuation of the terrain. For each triangular facet of the TIN, affine transformations are estimated and applied for rectification. Experiments with Quickbird, SPOT5, SPOT4, TM remote-sensing images of the Hangzhou area in China demonstrate the efficiency and the accuracy of the proposed technique for multi-source remote-sensing image registration. 相似文献
8.
Hierarchical classification of protein function with ensembles of rules and particle swarm optimisation 总被引:1,自引:1,他引:0
Nicholas Holden Alex A. Freitas 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(3):259-272
This paper focuses on hierarchical classification problems where the classes to be predicted are organized in the form of
a tree. The standard top-down divide and conquer approach for hierarchical classification consists of building a hierarchy
of classifiers where a classifier is built for each internal (non-leaf) node in the class tree. Each classifier discriminates
only between its child classes. After the tree of classifiers is built, the system uses them to classify test examples one
class level at a time, so that when the example is assigned a class at a given level, only the child classes need to be considered
at the next level. This approach has the drawback that, if a test example is misclassified at a certain class level, it will
be misclassified at deeper levels too. In this paper we propose hierarchical classification methods to mitigate this drawback.
More precisely, we propose a method called hierarchical ensemble of hierarchical rule sets (HEHRS), where different ensembles
are built at different levels in the class tree and each ensemble consists of different rule sets built from training examples
at different levels of the class tree. We also use a particle swarm optimisation (PSO) algorithm to optimise the rule weights
used by HEHRS to combine the predictions of different rules into a class to be assigned to a given test example. In addition,
we propose a variant of a method to mitigate the aforementioned drawback of top-down classification. These three types of
methods are compared against the standard top-down hierarchical classification method in six challenging bioinformatics datasets,
involving the prediction of protein function. Overall HEHRS with the rule weights optimised by the PSO algorithm obtains the
best predictive accuracy out of the four types of hierarchical classification method. 相似文献
9.
With the proliferation of macroergonomic field research, it is time to carefully examine how such research should be managed and implemented. We argue that the importance of attending to high-quality implementation of field research is equal to that of methodological rigor. One way to systematically manage the implementation process is to adopt a change management framework, wherein the research project is conceptualized as an instance of organization-level change. Consequently, principles for successful organization-level change from the literature on change management can be used to guide successful field research implementation. This paper briefly reviews that literature, deriving 30 principles of successful change management, covering topics such as political awareness, assembling the change team, generating buy-in, and management support. For each principle, corresponding suggestions for macroergonomic field research practice are presented. We urge other researchers to further develop and adopt frameworks that guide the implementation of field research. 相似文献
10.