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Test Patterns (test + pattern)
Selected AbstractsEvaluation of the improved three-dimensional resolution of a synchrotron radiation computed tomograph using a micro-fabricated test patternJOURNAL OF SYNCHROTRON RADIATION, Issue 6 2008Ryuta Mizutani A micro test pattern prepared by focused ion beam milling was used to evaluate the three-dimensional resolution of a microtomograph at the BL20B2 beamline of SPring-8. The resolutions along the direction within the tomographic slice plane and perpendicular to it were determined from the modulation transfer functions. The through-plane resolution perpendicular to the tomographic slice was evaluated to be 8,µm, which corresponds to the spatial resolution of two-dimensional radiographs. In contrast, the in-plane resolution within the slice was evaluated to be 12,µm. Real-space interpolation was performed prior to the tomographic reconstruction, giving an improved in-plane resolution of 8.5,µm. However, the 8,µm pitch pattern was resolved in the interpolated slice image. To reflect this result, another resolution measure from the peak-to-valley difference plot was introduced. This resolution measure gave resolution limits of 7.4,µm for the in-plane direction and 6.1,µm for the through-plane direction. The three-dimensional test pattern along with the interpolated reconstruction enables the quantitative evaluation of the spatial resolution of microtomographs. [source] What the honeybee sees: a review of the recognition system of Apis melliferaPHYSIOLOGICAL ENTOMOLOGY, Issue 1 2005Adrian Horridge Abstract., For many years, two opposing theories have dominated our ideas of what honeybees see. The earliest proposal based on training experiments was that bees detected only simple attributes or features, irrespective of the actual pattern. The features demonstrated experimentally before 1940 were the disruption of the pattern (related to spatial frequency), the area of black or colour, the length of edge, and the angle of orientation of a bar or grating. Cues discovered recently are the range, and radial and tangential edges, and symmetry, relative to the fixation point, which is usually the reward hole. This theory could not explain why recognition failed when the pattern was moved. In the second theory, proposed in 1969, the bee detected the retinotopic directions of black or coloured areas, and estimated the areas of overlap and nonoverlap on each test pattern with the corresponding positions in the training pattern. This proposal explained the progressive loss of recognition as a test pattern was moved or reduced in size, but required that the bees saw and remembered the layout of every learned pattern and calculated the mismatch with each test image. Even so, the same measure of the mismatch was given by many test patterns and could not detect a pattern uniquely. Moreover, this theory could not explain the abundant evidence of simple feature detectors. Recent work has shown that bees learn one or more of a limited number of simple cues. A newly discovered cue is the position, mainly in the vertical direction, of the common centre (centroid) of black areas combined together. Significantly, however, the trained bees look for the cues mentioned above only in the range of places where they had occurred during the training. These two observations made possible a synthesis of both theories. There is no experimental evidence that the bees detect or re-assemble the layout of patterns in space; instead, they look for a cue in the expected place. With an array of detectors of the known cues, together with their directions, this mechanism would enable bees to recognize each familiar place from the coincidences of cues in different directions around the head. [source] Modeling Age Differences in Infant Category LearningINFANCY, Issue 2 2004Thomas R. Shultz We used an encoder version of cascade correlation to simulate Younger and Cohen's (1983, 1986) finding that 10-month-olds recover attention on the basis of correlations among stimulus features, but 4- and 7-month-olds recover attention on the basis of stimulus features. We captured these effects by varying the score threshold parameter in cascade correlation, which controls how deeply training patterns are learned. When networks learned deeply, they showed more error to uncorrelated than to correlated test patterns, indicating that they abstracted correlations during familiarization. When prevented from learning deeply, networks decreased error during familiarization and showed as much error to correlated as to uncorrelated tests but less than to test items with novel features, indicating that they learned features but not correlations among features. Our explanation is that older infants learn more from the same exposure than do younger infants. Unlike previous explanations that postulate unspecified qualitative shifts in processing with age, our explanation focuses on quantitatively deeper learning with increasing age. Finally, we provide some new empirical evidence to support this explanation. [source] Personality Trait Profiles of Missionary AdolescentsJOURNAL OF TRAVEL MEDICINE, Issue 6 2000Terry L. Dwelle Background: The study objective was to compare the Taylor-Johnson Temperament Analysis secondary population norms for adolescents, to test results of Assemblies of God missionary adolescents, and determine if the mission's experience had significant impact on personality traits. Methods: A retrospective record review study of Taylor-Johnson Temperament Analysis test results administered to all missionary adolescents aged 13- to 18-years-old, having attended a yearly school of missions from 1986 to 1994, was performed. A two-sample, two-tailed t -test was used for statistical analysis. Test results were compared with standard adolescent and adult norms. Initial, and second test results when available, were compared for significant personality trait changes in adolescents over a 2,3 year interval, while in the mission's program. Subpopulation norms were calculated for the study group. Results: Initial tests from 438 study group adolescents demonstrated significant differences in 7 of 9 personality trait categories for males, and 8 of 9 for females, compared with test adolescent norms. Initial, and second test comparisons were performed in 67 adolescents, and showed no significant changes in the personality trait scores in males and females. Personality trait profiles for females more closely resembled adult than adolescent norms, with 8 of the 9 personality trait categories showing no significant difference between adult female norms and study females. Conclusions: Clinicians and mission's sending agencies should be aware of the unique Taylor-Johnson Temperament Analysis test patterns for missionary adolescents, and that Taylor-Johnson Temperament Analysis norm tables for adolescents seem inadequate in evaluating missionary adolescents. Appropriate subpopulation norms are likely necessary. The impact of missions on personality trait categories of missionary adolescents seems negligible, but needs further research with methods that assure follow-up testing. These considerations could apply to other subpopulations and psychological tests. [source] Liver test patterns in patients with acute calculous cholecystitis and/or choledocholithiasisALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2009M. S. PADDA Summary Background, Liver tests are utilized to determine the presence of biliary obstruction. Aim, To examine our hypothesis that liver tests aid in elucidating whether patients have simple calculous cholecystitis (ACC) or choledocholithiasis (CDL). Methods, We performed a retrospective study of patients admitted to two University of Texas Southwestern teaching hospitals with a clinical picture consistent with ,acute gallstone disease', i.e. cholecystitis ± choledocolithiasis. The presence of ACC and CDL was based on defined clinical criteria. Results, The cohort consisted of 154 patients meeting specific entry criteria, primarily with right upper quadrant pain; 62 ACC, 79 both ACC and CDL and 13 CDL alone. Approximately 30% of patients with ACC had abnormal alkaline phosphatase (ALP) and/or bilirubin level and approximately 50% had abnormal aminotransferase levels. Among patients with ACC/CDL, 77% had abnormal ALP, 60% had abnormal bilirubin and 90% had abnormal aminotransferase levels. By multivariate analysis, increasing common bile duct size and an abnormal ALP and alanine aminotransferase (ALT) were excellent predictors of having ACC with CDL. Conclusions, Liver test patterns can aid in elucidating CDL, including in ACC patients. Fundamentally, patients with CDL were more likely to have more abnormal liver tests, whether they had CDL only, or CDL and ACC. A dilated CBD, and abnormal ALP and ALT had modest sensitivity and high specificity for identification of patients with ACC and CDL. [source] What the honeybee sees: a review of the recognition system of Apis melliferaPHYSIOLOGICAL ENTOMOLOGY, Issue 1 2005Adrian Horridge Abstract., For many years, two opposing theories have dominated our ideas of what honeybees see. The earliest proposal based on training experiments was that bees detected only simple attributes or features, irrespective of the actual pattern. The features demonstrated experimentally before 1940 were the disruption of the pattern (related to spatial frequency), the area of black or colour, the length of edge, and the angle of orientation of a bar or grating. Cues discovered recently are the range, and radial and tangential edges, and symmetry, relative to the fixation point, which is usually the reward hole. This theory could not explain why recognition failed when the pattern was moved. In the second theory, proposed in 1969, the bee detected the retinotopic directions of black or coloured areas, and estimated the areas of overlap and nonoverlap on each test pattern with the corresponding positions in the training pattern. This proposal explained the progressive loss of recognition as a test pattern was moved or reduced in size, but required that the bees saw and remembered the layout of every learned pattern and calculated the mismatch with each test image. Even so, the same measure of the mismatch was given by many test patterns and could not detect a pattern uniquely. Moreover, this theory could not explain the abundant evidence of simple feature detectors. Recent work has shown that bees learn one or more of a limited number of simple cues. A newly discovered cue is the position, mainly in the vertical direction, of the common centre (centroid) of black areas combined together. Significantly, however, the trained bees look for the cues mentioned above only in the range of places where they had occurred during the training. These two observations made possible a synthesis of both theories. There is no experimental evidence that the bees detect or re-assemble the layout of patterns in space; instead, they look for a cue in the expected place. With an array of detectors of the known cues, together with their directions, this mechanism would enable bees to recognize each familiar place from the coincidences of cues in different directions around the head. [source] Real-time monitoring of injection molding for microfluidic devices using ultrasoundPOLYMER ENGINEERING & SCIENCE, Issue 4 2005Y. Ono Real-time process monitoring of the fabrication process of microfluidic devices using a polymer injection molding machine was carried out using miniature ultrasonic probes. A thick piezoelectric lead-zirconate-titanate film as an ultrasonic transducer (UT) was fabricated onto one end of a 4-mm diameter and 12-mm long steel buffer rods using a sol gel spray technique. The center frequency and 6 dB bandwidth of this UT were 17 MHz and 14 MHz, respectively. A signal-to-noise ratio of more than 30 dB for ultrasonic signals reflected at the probing end was achieved. The probe can operate continuously at 200°C without ultrasonic couplant and cooling. Clear ultrasonic signals were obtained during injection molding of a 1-mm-thick part having test patterns on its surface. Shrinkage of the molded part and part detachment from the mold were successfully monitored. Surface imperfections of the molded parts due to a lack of the sufficient holding pressure is discussed with regard to the ultrasonic velocity obtained. The presented ultrasonic probes and technique enable on-line quality control of the molded part by optimizing the holding pressure and improvement of process efficiency by reducing the cycle time. POLYM. ENG. SCI., 45:606,612, 2005. © 2005 Society of Plastics Engineers [source] Functional Electrical Stimulation-Induced Surface Muscle Stiffness Captured by Computer-Controlled TonometryARTIFICIAL ORGANS, Issue 3 2002Dietmar Rafolt Abstract: A new tonometric test system to assess surface stiffness over relaxed and activated calf muscles was developed. The mechanical arrangement consists of a skin indentor driven by a torque motor (galvo-drive) that is rigidly connected to an ankle dynamometer. The indentation depth is measured by a displacement transducer. Software routines for cyclic indentation (recording of stiffness curves), static indentation (sensing of twitch responses), and vibration (skin resonance) were implemented. A visual interface is used to capture surface stiffness during target contractions and during controlled relaxation. For functional electrical stimulation (FES) applications, the software includes a pulse train synthesizer to generate arbitrary stimulation test patterns. The system's performance was tested in FES and voluntary contraction procedures. [source] | ||||||||||