A methodology for the optimization of wet granulation in a model planetary mixer

This paper investigates a methodology for the optimization of wet granulation processes in planetary mixers. A model formulation was granulated in a planetary mixer (two different bowl sizes). The wet masses were characterized by their bulk density and consistency (as measured by mixer torque rheometry), and the feasibility of scale-up from one mixer bowl to the other was studied using a dimensionless numbers approach for the estimation of the power consumption at the granulation end point. Both bowls gave the same dimensionless power relationships (a relationship between the power number, Reynolds number, Froude number, and bowl fill ratio), which could therefore be used for calculating the power consumption level when the wet mass achieves its target values of density and consistency, i.e., the point at which granulation should be stopped. It was also shown that batches granulated in different conditions (batch size, blade speed) in two planetary mixers, but presenting similar wet mass characteristics (bulk density and consistency) led to dry granules of similar properties: granule size distribution, density, friability, and flow. This work suggests that it is possible to characterize the wet mass by only two parameters which describe the quality of the downstream granules. The scale-up procedure based on the use of dimensionless numbers was found to be applicable to planetary mixers, provided they give one common dimensionless power relationship.     

The eigenvalues-greater-than-one rule and the reliability of components.

A commonly used criterion for the number of factors to rotate is the eigenvalues-greater-than-one rule proposed by Kaiser (1960). It states that there are as many reliable factors as there are eigenvalues greater than one. The reasoning is that an eigenvalue less than one implies that the scores on the component would have negative reliability. I show here that this rule is the result of a misapplication of the formula for internal consistency reliability. I also present a formula for the reliability of a component; it depends on the eigenvalue and the reliability of the individual measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the capacity of spatially correlated MIMO Rayleigh-fading channels

In this paper, we investigate the capacity distribution of spatially correlated, multiple-input-multiple-output (MIMO) channels. In particular, we derive a concise closed-form expression for the characteristic function (c.f.) of MIMO system capacity with arbitrary correlation among the transmitting antennas or among the receiving antennas in frequency-flat Rayleigh-fading environments. Using the exact expression of the c.f., the probability density function (pdf) and the cumulative distribution function (CDF) can be easily obtained, thus enabling the exact evaluation of the outage and mean capacity of spatially correlated MIMO channels. Our results are valid for scenarios with the number of transmitting antennas greater than or equal to that of receiving antennas with arbitrary correlation among them. Moreover, the results are valid for an arbitrary number of transmitting and receiving antennas in uncorrelated MIMO channels. It is shown that the capacity loss is negligible even with a correlation coefficient between two adjacent antennas as large as 0.5 for exponential correlation model. Finally, we derive an exact expression for the mean value of the capacity for arbitrary correlation matrices.     

On the energy capture of ultrawide bandwidth signals in densemultipath environments

A quasi-analytical experimental analysis is described in this paper to quantify the tradeoff between energy capture and diversity level in a RAKE receiver using measured received waveforms obtained from ultrawide bandwidth signal propagation experiments     

Acetylcholine-activated chloride current in the T-84 colonic cell line

Plasma viral burden has proven valuable in predicting the future course of systemic HIV related disease and the response to treatment. It is not known whether plasma or cerebrospinal fluid (CSF) viral burden can be used to predict onset of or response to treatment of nervous system disease. We propose a model of viral load mediated neurotoxicity underlying peripheral and central HIV associated neurological disease. The objective of this preliminary study was to assess the relationship of HIV associated neurological disease to quantitative viral load in plasma and CSF. 47 subjects (HIV- = 10, HIV+ = 37) participated in the study. Plasma and CSF samples were collected within a 3 h window. RT-PCR (Roche Amplicor Monitor) was utilized to assess HIV-1 RNA viral load in both plasma and cell free (centrifuged) CSF. Subjects underwent concurrent comprehensive neurological and neuropsychological evaluations. In general, systemic viral load, as measured in plasma, was greater than that found in cell free CSF. Cell free CSF HIV RNA viral load was significantly correlated with neurological dysfunction, whereas plasma viral load was not. The sole subject with an elevated CSF viral load (> 5 Log 10), had HIV associated dementia (HAD) on clinical examination.     

Verification of illumination tolerance for photo-model-based cloth recognition

Globally, robots are being used in garment factories according to their advantages such as high precision, flexibility, and productivity. However, it is difficult for robots to deal with deformable objects such as cloths and strings automatically. The main tasks of such robots are to recognize a deformable object and to pick up and place it at a designated position automatically. The deformable character of cloths seems a main hindrance for automatic handling by robots, especially if the cloth is unique. In this paper, a cloth handling robotic system for unique cloths is proposed with consideration of verification of illumination tolerance. This robotic system comprises two main portions: the first portion generates a model of cloths using an image taken by a single camera, and the second portion estimates the relative pose of cloth appeared in the view of two cameras using the generated model. In our cloths’ pose estimation, the photo-model projected from 3D to 2D is used, where this system does not need defining the object’s size, shape, design, color, and weight. The illumination tolerance of the proposed system under different light conditions of different light sources was verified experimentally for evaluating the proposed system from the view point of practicality. The fluorescent light and the light-emitting diode (LED) light are used in this experiment, having confirmed that the proposed system can recognize cloths in condition that the light environments have varieties.     

The effects of topographic correction and gap filling in imagery on the detection of tropical forest disturbances using a Landsat time series in Myanmar

In this study, we evaluated the effects of topographic correction and gap filling of Landsat Enhanced Thematic Mapper Plus (ETM+) images on the accuracy of forest change detection through a trajectory-based approach. Four types of Landsat time series stacks (LTSS) were generated. These stacks resulted from combinations of topographically corrected and uncorrected imagery combined with gap-filled and unfilled stacks. These combinations of stacks were then used as input into a trajectory-based change detection. The results of change detection from trajectory-based analysis using these LTSS were compared in order to assess the effects of both topographic correction and gap-filling procedures on the ability to detect forest disturbances. The results showed that overall accuracies of change detection were improved after gap filling (10.5% and 7.5%), but were only slightly improved after topographic correction (3.6% and 0.6%). Although the gap-filling process introduced some uncertainty that might have caused false change detection, the number of pixels whose detection of disturbance was enhanced after gap filling exceeded those detecting false change. The results also showed that the topographic correction did not contribute much to improve the change detection in this study area. However, topographic correction has a potential to increase the accuracy of change detection in areas of more rugged terrain and steep slopes. This is because a direct relationship between the slope of the topography with topographic correction and an enhanced detection of disturbance in pixels from year to year was observed in this study. For robust change detection, we recommend that a gap-filling process should be included in the trajectory-based analysis procedures such as the one used in this study where a single image per year is used to characterize change. We also recommend that in areas of rugged terrain, a topographic correction in the image pre-processing should be implemented.     

Dynamics of spacecraft with elastic and dissipative elements in the attitude control mode

Rotational motion of a spacecraft with elastic and dissipative elements as a whole about its center of mass taking into account the control elements designed as single-axis gyrostabilizers in the attitude control mode is studied. Oscillatory processes related to the spacecraft attitude control when the terms emerging due to the elastic oscillations of the structure are comparable with gyroscopic terms. A model problem of spacecraft reorientation is considered. Conditions under which the elastic oscillations do not affect the flat slew of the satellite and assumptions under which no flat slew is possible are obtained. Analytical expressions for estimating the spacecraft deviations from the programmed motion (drift of the angular velocity) are found.