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101.
Orientation-dependent developments in misorientation and residual stress, in rolled aluminum, were quantified experimentally and simulated numerically. The latter involved analysis using a crystal plasticity finite element model, accounting for anisotropies in slip system hardening but neglecting near-neighbor interactions, and discrete dislocation dynamics of the single crystals. Both were successful in capturing the experimental patterns of orientation dependence. Numerical simulations, without slip transfer across the neighboring grains, thus established the defining role of dislocation interactions in establishing orientation-sensitive microstructural evolution.  相似文献   
102.
International Journal on Document Analysis and Recognition (IJDAR) - Separation of text and non-text is an essential processing step for any document analysis system. Therefore, it is important to...  相似文献   
103.
Multimedia Tools and Applications - In the era of the smart classroom environment, students’ affective content analysis plays a vital role as it helps to foster the affective states that are...  相似文献   
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105.
Ferritic steel weldments are invariably post-weld heat treated for relieving the residual stresses. However, the long duration of post-weld heat treatment (PWHT) required for very thick weldments can adversely affect the mechanical properties and fracture toughness. Thus, there is a need to establish the relative importance of temperature and time of PWHT with respect to stress relief. Accordingly, in the present work, the phenomenon of stress relief (due to PWHT) in an 800-mm-thick steel weldment was investigated using finite element analysis and the results were validated against experimental measurements. An analytical study was also carried out to determine the relative influence of temperature and time of PWHT on stress relief. It was found that time of PWHT plays a more significant role in case of relatively lower PWHT temperatures. It was also found that, for a given value of Hollomon parameter, different combinations of PWHT temperature and time can be employed to achieve the same level of stress relief. A mathematical relationship has been established between Hollomon parameter and magnitude of residual stress after PWHT. It has been shown that residual stress is a monotonically decreasing function of the Hollomon parameter.  相似文献   
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In this work, SPECT brain images are analyzed automatically in order to determine the effects of acupuncture applied for fighting migraine. For this purpose, two different groups of patients are randomly collected and received verum and sham acupuncture, respectively. Changes in the brain perfusion patterns can be measured quantitatively by dealing with the images in a classification context. A classification scheme consisting of a component-based feature extraction technique in combination with Support Vector Machines allows us to accurately determine the regions of interest (ROIs) where acupuncture produced more intense effects, and whether these effects are correlated with a decrease or an increase of the brain activity. Effects produced by verum and sham acupuncture are studied, and the best method for intensity normalization is discussed. The result is a complete, objective system which can be used for general purposes in the visual assessment of perfusion images.  相似文献   
108.
The impact of external mass transport on the biodegradation rate of phenol in a packed bed bioreactor (PBBR) was studied. A potential bacterial species, Bacillus flexus GS1 IIT (BHU), was isolated from the petroleum‐contaminated soil. Low‐density polyethylene (LDPE) immobilized with the B. flexus GS1 IIT (BHU) was used as packing material in the PBBR. The PBBR was operated by varying the inlet feed flow rate from 4 to 10 mL/min, and the corresponding degradation rate coefficients were found to be in the range of 0.119–0.157 L/g h. In addition, the highest removal rate of phenol was obtained to be 1.305 mg/g h at an inlet feed rate of 10 mL/min. The external mass transfer was studied using the model . A new empirical correlation for the biodegradation of phenol in the PBBR was developed after the evaluation at various values of K and n.  相似文献   
109.
Feature selection through optimization techniques provides an interesting approach to minimize computational time with enhanced prediction capability, and  相似文献   
110.
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