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101.
RS Daum D Hogerman MB Rennels K Bewley F Malinoski E Rothstein K Reisinger S Block H Keyserling M Steinhoff 《Canadian Metallurgical Quarterly》1997,176(2):445-455
Six pentavalent pneumococcal conjugate vaccines (Pn-CRM197) were evaluated among 400 infants. The vaccines differed in saccharide chain length (oligosaccharide [OS] or polysaccharide [PS]) and saccharide quantity (0.5, 2, or 5 microg). Subjects were randomized into groups 1-6 (Pn-CRM197 recipients) or 7 (controls) for immunization at 2, 4, and 6 months of age. Pn-CRM197 were well tolerated and elicited mean antibody concentrations that exceeded those in controls for all 5 capsular serotypes. PS formulations were generally more immunogenic than their OS counterparts. For PS vaccines, a dose-response was documented (5 microg > 2 microg > 0.5 microg), but the differences between the 5- and 2-microg formulations were insignificant. The mean anti-PRP antibody concentration was significantly higher among Pn-CRM197 recipients. It is concluded that PS vaccines are more immunogenic than OS vaccines. The improved immunogenicity from Haemophilus type b oligosaccharide conjugate (HbOC) vaccine when given with Pn-CRM197 suggests that a decreased dose of HbOC vaccine may be sufficient to elicit protection. 相似文献
102.
Simulation with Object Oriented Programming (SW-OOP) is a library of software modules (classes) designed to provide the software constructs necessary for programming general purpose discrete event computer simulations in Pascal.
Systems modeling and simulation has been cited by those disciplined in operations research and management science as one of the skills most frequently applied to the study, understanding and improvement of systems in industry (Law 1991).
This paper presents SW-OOP and discusses how it is used to facilitate systems modeling and simulation when computer software is developed to study a particular problem. 相似文献
103.
An unexpected transient creep behavior characterized by a stress exponent of 1 was observed at low stresses in tin alloys
strengthened by large volume fractions (>15 pct) of the precipitate SbSn. By way of solid-state precipitation, SbSn forms
as high-aspect ratio whiskers. At large volume fractions, whiskers are both directly and indirectly observed to be in direct
contact with multiple other whiskers. The transient creep behavior is attributed to a phase-boundary-enhanced diffusional
creep mechanism, possibly diffusional creep along continuous phase-boundary paths between tin grain boundaries. It is thought
that the creep behavior is, in fact, a “steady-state” behavior characteristic of the initial microstructure. The ultimate
transient nature is due to precipitate coarsening occurring with time during the creep test. 相似文献
104.
105.
Swain Rodney A.; Shinkman Paul G.; Nordholm Alan F.; Thompson Richard F. 《Canadian Metallurgical Quarterly》1992,106(5):739
Implanted rabbits with chronic stimulating electrodes in white matter underlying lobule HVI of the cerebellar cortex. Stimulation elicited movements of the face or neck and, when paired with a tone CS, produced learning comparable to that seen with peripheral unconditioned stimulus/stimuli (UCS). CS-alone trials produced extinction. Reinstatement of paired trials produced reacquisition with savings. Additional groups received either explicitly or randomly unpaired CS–UCS trials before paired conditioning. Low-frequency responding during these sessions indicated that the paired training results were associative and not due to pseudoconditioning or sensitization. Explicitly unpaired sessions retarded learning on subsequent paired trials compared with groups that received either randomly unpaired or no CS–UCS preexposure. These results are interpreted in terms of the role of the cerebellum and associated pathways in classical conditioning of motor responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Rodney J. Sobey 《Canadian Metallurgical Quarterly》2001,127(10):805-824
An analysis of the predictive capabilities of cross-section–integrated models of gradually varied, unsteady flow in channels initially highlights the physical characteristics of the conservation equations, with particular emphasis on those aspects that are operationally crucial or potentially challenged in numerical implementation. A sequence of benchmark test problems are introduced with the express purpose of evaluating all potentially important features of expected response patterns. This sequence of problems is designed to exercise the physically and numerically significant response patterns that are expected to be within the predictive capability of numerical models of flood and tide propagation in channels. An extensive and independent review of this nature should be a routine and automatic part of any numerical model study. 相似文献
107.
108.
A hybrid finite-volume (FV)/transported probability density function (PDF) method is used for the simulation of a partially premixed flame with detailed chemistry. The FV code is implemented to handle detailed chemistry implicitly with no subgrid closure. A partially premixed methane-air flame is simulated to illustrate the need for closure. The PDF scheme is then substituted to handle the species transport using a subgrid mixing model. The algorithmic modifications to the PDF code are discussed in the context of a generalized structured grid solution technique. A multi-step particle transport algorithm is used to eliminate grid dependence of the time step. A detailed chemistry mechanism (GRI-2.11) is handled using in situ adaptive tabulation. It is shown that with simple modifications, the Interaction by Exchange with the Mean mixing model is able to predict the flame quite accurately. Mean profiles and conditional means obtained using the 49-species GRI-2.11 and 53-species GRI-3.0 mechanisms and the 16-species Augmented Reduced Mechanism are compared with the experimental data from the Sandia D flame. It is shown that with the mixing model, good agreement with the experimental data is achieved. Also the effect of the value of the mechanical-to-scalar time-scale ratio used in the mixing model is analyzed. The effect of the model constants in the dissipation equation for the turbulence model and the effect of radiation on flame predictions are also discussed. 相似文献
109.
110.
Mrityunjay Kumar David D. Conger Rodney L. Miller Jiebo Luo Hayder Radha 《Journal of Signal Processing Systems》2011,65(2):159-169
As displays become less expensive and are incorporated into more and more devices, there has been an increased focus on image
resizing techniques to fill an image to an arbitrary screen size. Traditional methods such as cropping or resampling can introduce undesirable losses in information or distortion in perception. Recently, content-aware image retargeting methods
have been proposed (Avidan and Shamir, ACM Trans Graphics 26(3), 2007; Guo et al., IEEE Trans Multimedia 11(5):856–867, 2009; Shamir and Avidan, Commun ACM 52(1), 2009; Simakov et al. 2008; Wolf et al. 2007), which produce exceptional results. In particular, seam carving, proposed by Avidan and Shamir, has gained attention as
an effective solution. However, there are many cases where it can fail. In this paper we propose a distortion-sensitive seam
carving algorithm for content-aware image resizing that improves edge preservation and decreases aliasing artifacts. In the
proposed approach, we use local gradient information along with a thresholding technique to guide the seam selection process
and provide a mechanism to halt seam carving when further processing would introduce unacceptable visual distortion in the
resized image. Furthermore, anti-aliasing filter is used to reduce the aliasing artifacts caused by seam removal. Experiments
have demonstrated superior performance over the current seam carving methods. 相似文献