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排序方式: 共有489条查询结果,搜索用时 23 毫秒
441.
Ponomaryov Volodymyr Montenegro Hector Rosales Alberto Duchen Gonzalo 《Journal of Real-Time Image Processing》2015,10(2):313-328
Journal of Real-Time Image Processing - A novel fuzzy 3D filter designed to suppress impulsive noise in color video sequences is proposed. In contrast to other state-of-the-art algorithms, the... 相似文献
442.
Due to the manufacturing process Ti-6Al-4V alloy exhibited a very strong anisotropic texture caused by the existence of a preferred crystallographic orientation in the polycrystalline microstructure. This crystallographic alignment can result in anisotropic behavior of the material so that the material properties are different depending on whether they are measured in perpendicular or parallel direction. In addition to this morphological anisotropy, due to the dominantly hexagonal grain structure, the Ti-6Al-4V alloy also exhibited a substantial thermoelectric anisotropy. This study was conducted to investigate the effect of thermoelectric anisotropy on the thermoelectric power measurements in a highly textured Ti-6Al-4V specimen using a completely non-destructive technique based on the Seebeck effect. The result shows the thermoelectric power dependence associated with texturing and the macroscopic grain structure in a rolled Ti-6Al-4V specimen which was annealed at 710 °C for 2 h and slowly cooled. The measurements clearly demonstrate that the intrinsic sensitivity of the thermoelectric contact technique is a very useful tool that could be exploited for QND material characterization. 相似文献
443.
Lahey Benjamin B.; Schwab-Stone Mary; Goodman Sherryl H.; Waldman Irwin D.; Canino Glorisa; Rathouz Paul J.; Miller Terri L.; Dennis Kimberly D.; Bird Hector; Jensen Peter S. 《Canadian Metallurgical Quarterly》2000,109(3):488
Behavior problems among youths cannot be understood without explaining their age and gender differences, but age and gender differences cannot be explained until they have been accurately described. In a household survey of 1,285 youths aged 9 to 17 years, there were no gender differences in oppositional behavior, but aggression, property offenses, and status offenses were more common among boys. Levels of oppositional behavior were greater at younger ages, aggression peaked near the middle of this age range, and property and status offenses were more prevalent at older ages. These findings are generally consistent with developmental models of conduct problems but are inconsistent with a recent model of gender differences and raise questions about the external validity of current taxonomies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
444.
RI Hector 《Canadian Metallurgical Quarterly》1998,43(5):466-472
The effect of coadministration of ritonavir and didanosine (ddI) on the pharmacokinetics of these drugs was investigated in a single-center, three-period, crossover study. Eighteen asymptomatic, HIV-positive men were assigned randomly to 6 different sequences of 3 regimens: ddI (200 mg every 12 hours) alone for 4 days, ritonavir (600 mg every 12 hours) alone for 4 days, and 4 days of ddI with ritonavir under dose-staggering conditions. Although not statistically significant, ritonavir concentrations were slightly higher on average (<10%) with concurrent administration of ddI compared with those of ritonavir alone. In contrast, ddI concentrations were lower with concurrent administration compared with those of ddI alone; maximum concentration and area under the concentration-time curve were reduced by about 15% (p < .05). The ddI elimination rate constant was unaffected by ritonavir, suggesting no change in ddI's systemic metabolism. Adverse events were similar between regimens. The relatively minor changes in ritonavir and ddI pharmacokinetics are probably not clinically relevant; therefore, dosage adjustment of either compound appears unnecessary when administered concurrently. However, the combination regimen of ddI and ritonavir continue to be evaluated clinically. 相似文献
445.
J.Carlos Siska Ricard H. Espinosa David A. Trevio Junipero Rodriguez Juan D. Sanchez Hector Ramirez 《Computers & Graphics》1988,12(3-4):381-389
This paper describes the main features of ADROS System: The 2D module DDC (Design and Drafting by Computer) and the 3D module SM (Solid Modeler). 相似文献
446.
447.
Query processing and inverted indices in shared-nothing text document information retrieval systems 总被引:1,自引:0,他引:1
Anthony Tomasic M.A. Ph.D. Candidate Hector Garcia-Molina Ph.D. 《The VLDB Journal The International Journal on Very Large Data Bases》1993,2(3):243-275
The performance of distributed text document retrieval systems is strongly influenced by the organization of the inverted text. This article compares the performance impact on query processing of various physical organizations for inverted lists. We present a new probabilistic model of the database and queries. Simulation experiments determine those variables that most strongly influence response time and throughput. This leads to a set of design trade-offs over a wide range of hardware configurations and new parallel query processing strategies. 相似文献
448.
A path-based approach for web page retrieval 总被引:1,自引:0,他引:1
Use of links to enhance page ranking has been widely studied. The underlying assumption is that links convey recommendations.
Although this technique has been used successfully in global web search, it produces poor results for website search, because
the majority of the links in a website are used to organize information and convey no recommendations. By distinguishing these
two kinds of links, respectively for recommendation and information organization, this paper describes a path-based method
for web page ranking. We define the Hierarchical Navigation Path (HNP) as a new resource for improving web search. HNP is
composed of multi-step navigation information in visitors’ website browsing. It provides indications of the content of the
destination page. We first classify the links inside a website. Then, the links for web page organization are exploited to
construct the HNPs for each page. Finally, the PathRank algorithm is described for web page retrieval. The experiments show
that our approach results in significant improvements over existing solutions. 相似文献
449.
In this paper we study in what order a crawler should visit the URLs it has seen, in order to obtain more “important” pages first. Obtaining important pages rapidly can be very useful when a crawler cannot visit the entire Web in a reasonable amount of time. We define several importance metrics, ordering schemes, and performance evaluation measures for this problem. We also experimentally evaluate the ordering schemes on the Stanford University Web. Our results show that a crawler with a good ordering scheme can obtain important pages significantly faster than one without. 相似文献
450.
An adaptive control algorithm with a neural network model, previously proposed in the literature for the control of mechanical manipulators, is applied to a CSTR (Continuous Stirred Tank Reactor). The neural network model uses either radial Gaussian or “Mexican hat” wavelets as basis functions. This work shows that the addition of linear functions to the networks significantly improves the error convergence when the CSTR is operated for long periods of time in a neighborhood of one operating point, a common scenario in chemical process control. Then, a quantitative comparative study based on output errors and control efforts is conducted where adaptive controllers using wavelets or Gaussian basis functions and PID controllers (IMC tuning with fixed parameters and self tuning PID) are compared. From this comparative study, the practicality and advantages of the adaptive controllers over fixed or adaptive PID control is assessed. 相似文献