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Better Performers (good + performer)
Selected AbstractsNEURAL NETWORK MODELING OF END-OVER-END THERMAL PROCESSING OF PARTICULATES IN VISCOUS FLUIDSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2010YANG MENG ABSTRACT Modeling of the heat transfer process in thermal processing is important for the process design and control. Artificial neural networks (ANNs) have been used in recent years in heat transfer modeling as a potential alternative to conventional dimensionless correlation approach and shown to be even better performers. In this study, ANN models were developed for apparent heat transfer coefficients associated with canned particulates in high viscous Newtonian and non-Newtonian fluids during end-over-end thermal processing in a pilot-scale rotary retort. A portion of experimental data obtained for the associated heat transfer coefficients were used for training while the rest were used for testing. The principal configuration parameters were the combination of learning rules and transfer functions, number of hidden layers, number of neurons in each hidden layer and number of learning runs. For the Newtonian fluids, the optimal conditions were two hidden layers, five neurons in each hidden layer, the delta learning rule, a sine transfer function and 40,000 learning runs, while for the non-Newtonian fluids, the optimal conditions were one hidden layer, six neurons in each hidden layer, the delta learning rule, a hyperbolic tangent transfer function and 50,000 learning runs. The prediction accuracies for the ANN models were much better compared with those from the dimensionless correlations. The trained network was found to predict responses with a mean relative error of 2.9,3.9% for the Newtonian fluids and 4.7,5.9% for the non-Newtonian fluids, which were 27,62% lower than those associated with the dimensionless correlations. Algebraic solutions were included, which could be used to predict the heat transfer coefficients without requiring an ANN. PRACTICAL APPLICATIONS The artificial neural network (ANN) model is a network of computational elements that was originally developed to mimic the function of the human brain. ANN models do not require the prior knowledge of the relationship between the input and output variables because they can discover the relationship through successive training. Moreover, ANN models can predict several output variables at the same time, which is difficult in general regression methods. ANN concepts have been successfully used in food processing for prediction, quality control and pattern recognition. ANN models have been used in recent years for heat transfer modeling as a potential alternative to conventional dimensionless correlation approach and shown to be even better performers. In this study, ANN models were successfully developed for the heat transfer parameters associated with canned particulate high viscous Newtonian and non-Newtonian fluids during an end-over-end rotation thermal processing. Optimized configuration parameters were obtained by choosing appropriate combinations of learning rule, transfer function, learning runs, hidden layers and number of neurons. The trained network was found to predict parameter responses with mean relative errors considerably lower than from dimensionless correlations. [source] A conception-based approach to automatic subject term assignment for scientific journal articlesPROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2006EunKyung Chung This study proposes a conception-based approach to automatic subject term assignment when using Text Classification (TC) techniques. From the perspective of conceptual and theoretical views of subject indexing, this study identifies three conception-based approaches, Domain-Oriented, Document-Oriented, and Content-Oriented, in conjunction with eight semantic sources in typical scientific journal articles. Based on the identification of semantic sources and conception-based approaches, the experiment explores the significance of individual semantic sources and conception-based approaches for the effectiveness of subject term assignment. The results of the experiment demonstrate that some semantic sources and conception-based approaches are better performers than the full text-based approach which has been dominant in TC fields. In fact, this study indicates that subject terms are better assigned by TC techniques when the indexing conceptions are considered in conjunction with semantic sources. [source] Abnormal radiographic findings in 865 French Standardbred trotters and their relationship to racing performanceEQUINE VETERINARY JOURNAL, Issue S36 2006A. COUROUCÉ-MALBLANC Summary Reason for performing study: Developmental orthopaedic lesions are commonly found in French Standardbred horses. One of the main questions asked by trainers, owners and veterinarians is what impact these lesions have on the racing career and racing performances of horses. Objectives: To study the prevalence and distribution of developmental orthopaedic lesions in young French Standardbred trotters and to relate them to racing performance. Methods: Feet, fetlock, tarsus and stifle regions were radiographed in 865 two-year-old French Standardbred trotters. Abnormal radiographic findings (ARF) were evaluated for 12 anatomical sites identified in these areas, and a severity index given. Performance criteria were: success in qualification for racing, maximal and mean index of trot (ITR), an annual index calculated on the basis of the logarithm of earnings per starts, total earnings at 5 years, placed races compared to starts and longevity of the racing career. Analysis of variance were calculated to study the relationships between racing performance and the number of ARF or the severity index. Results: A total of 363 horses (42.0%) showed ARF. Prevalence of ARF was 18.3% in the plantar aspect of the hind fetlock and 10.6% in the proximal tarsus. Among the total population, 833 horses were considered for performance evaluation, 478 of them were qualified for racing. The number of ARF significantly affected racing longevity. However, the number of ARF did not affect performance categories according to maximal ITR. Concerning distribution of ARF, the number of plantar lesions in the fetlock significantly affected mean ITR. The index of severity did not provide more information for prognosis than the number of ARF. Conclusion: Longevity is the only criteria affected by ARF. When evaluating different sites, only the plantar fetlock region showed a significant relationship with mean ITR. Potential relevance: Number of ARF and radiographic score (RS) affect mean ITR and longevity but do not affect maximal ITR. A horse with a good racing ability will be a good performer but might have a racing career shortened because of orthopaedic problems in relation to developmental orthopaedic lesions. [source] Behavioral relevance of gamma-band activity for short-term memory-based auditory decision-makingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2008Jochen Kaiser Abstract Oscillatory activity in the gamma-band range has been established as a correlate of cognitive processes, including perception, attention and memory. Only a few studies, however, have provided evidence for an association between gamma-band activity (GBA) and measures of behavioral performance. Here we focused on the comparison between sample and test stimuli S1 and S2 during an auditory spatial short-term memory task. Applying statistical probability mapping to magnetoencephalographic recordings from 28 human subjects, we identified GBA components distinguishing nonidentical from identical S1,S2 pairs. This activity was found at frequencies between 65 and 90 Hz and was localized over posterior cortical regions contralateral to the hemifield in which the stimuli were presented. The 10 best task performers showed higher amplitudes of this GBA component than the 10 worst performers. This group difference was most pronounced between about 150 and 300 ms after stimulus onset. Apparently the decision about whether test stimuli matched the stored representation of previously presented sample sounds relied partly on the oscillatory activation of networks representing differences between both stimuli. This result could be replicated by reanalyzing the combined data from two previous studies assessing short-term memory for sound duration and sound lateralization, respectively. Similarly to our main study, GBA amplitudes to nonmatching vs. matching S1,S2 pairs were higher in good performers than poor performers. The present findings demonstrate the behavioral relevance of GBA. [source] Predictors of Grade 2 Word Reading and Vocabulary Learning from Grade 1 Variables in Spanish-Speaking Children: Similarities and DifferencesLEARNING DISABILITIES RESEARCH & PRACTICE, Issue 1 2008Alexandra Gottardo We examined the components of first (L1) and second language (L2) phonological processing that are related to L2 word reading and vocabulary. Spanish-speaking English learners (EL) were classified as average or low readers in grades 1 and 2. A large number of children who started out as poor readers in first grade became average readers in second grade while vocabulary scores were more stable. Binary logistic regressions examined variables related to classifications of consistently average, consistently low, or improving on reading or vocabulary across grades. Good L2 phonological short-term memory and phonological awareness scores predicted good reading and vocabulary scores. L1 and L2 measures differentiated consistently good performers from consistently low performers, while only L2 measures differentiated children who improved from children who remained low performers. Children who are EL should be screened on measures of pseudoword repetition and phonological awareness with low scorers being good candidates for receiving extra assistance in acquiring L2 vocabulary and reading. This study suggests measures that can be used to select children who have a greater likelihood of experiencing difficulties in reading and vocabulary. [source] | ||||||||||