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111.
Ore sorting is a useful tool to remove gangue material from the ore and increase the quality of the ore. The vast developments in the area of artificial intelligence allow fast processing of full color digital images for the preferred investigations. Three different approaches to color texture analysis were used for the classification of associated gangue from limestone and iron ore. All the methods were based on extensions of the co-occurrence matrix method. The first approach was a correlation method, in which co-occurrence matrices are computed both between and within the color bands. In the second approach, joint color-texture features, where color features were extracted from chrominance information and texture features were extracted from luminance information of the color bands. The last approach used grey scale texture features computed on a quantized color image. Results showed that the joint color-texture method was 98% accurate for limestone and 98.4% for iron ore gangue classification. It was further observed that the features showed better accuracy with 64 grey levels quantization.  相似文献   
112.
This letter describes the design, modeling, simulation, and fabrication of novel integrated passive devices (IPDs). These IPDs, comprising of a cofired multilayered varistor and inductor, have been developed in the ceramic coprocessing technology. The equivalent model of the new structures is presented, suitable for design and circuit simulations. The fabrication method, new design of structures and patented materials of these devices lead to improved characteristics suitable for application in high-frequency suppressors. The IPDs were tested in the frequency range of 1 MHz-3 GHz using an Agilent 4287A RF LCR meter. The measurements confirm the validity of the proposed model.  相似文献   
113.
Raghavendra  C.S. 《Micro, IEEE》1984,4(6):44-53
Computer systems with large numbers of processors pose serious reliability problems. One solution is to build redundant communication paths and dynamic reconfiguration into network designs.  相似文献   
114.
The preliminary design of iron-based permeable reactive barriers is often accomplished using analytic expressions for one-dimensional groundwater flow and contaminant transport. Typically, one or more of the governing processes is simplified or neglected to facilitate development of a tractable solution. This paper presents a set of improved design equations that include the effects of dispersion, finite domain boundary, sequential decay, and production processes, and increased flow through high conductivity barriers. When applied to realistic example problems, application of the expanded design equations typically results in the specification of a larger permeable reactive barrier thickness than obtained using conventional approaches.  相似文献   
115.
The present investigation studied the effects of enhancements on the learning, retention, transfer to the unlearned form, and use of Blissymbols in 40 normal 3-year-old children. The subjects, seen individually, learned either 12 standard Blissymbols (SBS) or the same 12 symbols in the enhanced form (EBS). The symbols were introduced with short explanations. The number of trials taken to reach > 90% correct identification, the number of symbols selected appropriately to complete a communicative act, the number of symbols correctly identified a week after the acquisition phase was completed, and the number of symbols correctly identified in the untrained form of Blissymbols were determined. The results demonstrated that the subjects learned EBS faster than SBS, remembered more EBS than SBS in the retention task, did not differ in the communicative use of SBS and EBS, and were affected more negatively when presented with SBS than EBS in a task where the untrained form was presented. The results are discussed in terms of how very young children might benefit more from an illustration system such as EBS than from an orthographic system such as SBS.  相似文献   
116.
Cu-44Ni-5Cr alloy has been subjected to thermomechanical treatment which consisted of plastic deformation of as-quenched material by 50, 65 and 80% reduction in thickness followed by ageing in the interval of 500 to 650 °C for various durations of time. Progress in age-hardening was studied by means of hardness measurement and X-ray diffraction studies. The wavelength of composition modulation and strain amplitude were measured. It was found that age-hardening was a result of interaction between spinodal decomposition and recovery processes. Prior deformation was found to enhance the kinetics of both spinodal decomposition and coarsening. It was concluded that this resulted from increased vacancy concentration and increased coherency strain in the cold-worked material.  相似文献   
117.
118.

Heart is an important and hardest working muscular organ of the human body. Inability of the heart to restore normal perfusion to the entire body refers to cardiac failure, which then with symptoms results in manifestation of congestive heart failure (CHF). Impairment in systolic function associated with chronic dilation of left ventricle is referred as dilated cardiomyopathy (DCM). The clinical examination, surface electrocardiogram (ECG), chest X-ray, blood markers and echocardiography play major role in the diagnosis of CHF. Though the ECG manifests chamber enlargement changes, it does not possess sensitive marker for the diagnosis of DCM, whereas echocardiographic assessment can effectively reveal the presence of asymptomatic DCM. This work proposes an automated screening method for classifying normal and CHF echocardiographic images affected due to DCM using variational mode decomposition technique. The texture features are extracted from variational mode decomposed image. These features are selected using particle swarm optimization and classified using support vector machine classifier with different kernel functions. We have validated our experiment using 300 four-chamber echocardiography images (150: normal, 150: CHF) obtained from 50 normal and 50 CHF patients. Our proposed approach yielded maximum average accuracy, sensitivity and specificity of 99.33%, 98.66% and 100%, respectively, using ten features. Thus, the developed diagnosis system can effectively detect CHF in its early stage using ultrasound images and aid the clinicians in their diagnosis.

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119.
In the present study we have shown the potential memory enhancing property of losartan, a selective Ang II AT1 receptor antagonist. Nootropic activity of losartan in mice was assessed by using passive avoidance step-down task and elevated plus-maze as a measure of short-term working and spatial memory respectively. Losartan at higher dose (10 mg/kg i.p) improved the basal performance in retention testing in both the test paradigms. Prior administration of losartan also attenuated retention deficit induced by scopolamine (0.3 mg/kg i.p). Moreover, physostigmine (0.05 mg/kg i.p) potentiated memory enhancing properties of losartan administered at lower dose (5 mg/kg i.p). On the basis of above observations it is concluded that the memory enhancing properties of losartan can be attributed to increased cholinergic activity.  相似文献   
120.
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