Reflectance calibration of aerial video imagery with automatic gain compensation on and off

Abstract

Video imaging systems are noi radiometrically calibrated, thus it is difficult to obtain quantitative remotely-sensed imagery for natural resource applications. Video camera automatic gain controls (AGC) present potential problems in calibrating video systems for quantitative analysis because they compensate for changing solar illumination conditions. In this experiment aerial video calibrations to ground reflectance standards were compared for AGC turned on and off, The calibrated aerial video was evaluated for guinea grass (Panicum maximum L.) biomass treatments on two dates. Results showed that there was more atmospheric light scattering in the red than in the NIR video band. Light scattering affects could be detected only when the AGC was ofT because when AGC was on light scattering affects were masked. These results also showed that video imagery produced significant correlations with guinea grass biomass that were comparable to ground reflectance measurements.     

SIMULATION BASED PERFORMANCE ANALYSIS of CRAWFISH PROCESSING OPERATIONS1

A detailed model of crawfish processing operations was developed using the SLAM II simulation language. the simulation model was used to compare overall plant performance for two crawfish cooking schemes, boiling water and steam infusion, and to evaluate processing parameters for different plant capacities. For all the range of operating levels included in this study (2,400-19,000 lb of live crawfish/day or 360-2,900 lb of tail meat/day), the steam infusion cooking scheme rendered shorter processing times than those required by the boiling water cooking scheme. Moreover, the batch sizes and amount of resources used are smaller for the steam infusion cooking scheme. the simulation model is a valuable tool to analyze the performance of crawfish plants as well as to determine the impact of changes in technology on the overall process.     

H∞ position transfer and regulation for floating offshore wind turbines

This paper proposes ${\rm H}_\infty$ controller design for platform position transfer and regulation of floating offshore wind turbines. The platform movability of floating wind turbines can be utilized in mitigating the wake effect in the wind farm, thereby maximizing the wind farm''s total power capture and efficiency. The controller is designed so that aerodynamic force is adjusted to meet the three objectives simultaneously, that is, 1) to generate the desired electrical power level, 2) to achieve the desired platform position, and 3) to suppress the platform oscillation. To acquire sufficient aerodynamic force to move the heavy platform, the pitch-to-stall blade pitching strategy is taken instead of the commonly-used pitch-to-feather strategy. The desired power level is attained by the standard constant-power strategy for the generator torque, while ${\rm H}_\infty$ state-feedback control of blade pitch and nacelle yaw angles is adopted for the position regulation and platform oscillation suppression. Weighting constants for the ${\rm H}_\infty$ controller design are adjusted to take the trade-off between the position regulation accuracy and the platform motion reduction. To demonstrate the efficiency of the proposed controller, a virtual 5-MW semi-submersible wind turbine is considered. Simulation results show that the designed ${\rm H}_\infty$ controller successfully accomplishes the platform position transfer and regulation as well as the platform oscillation reduction against wind and wave disturbances, and that it outperforms a previously-proposed linear quadratic controller with an integrator.     

Multi‐walled carbon nanotubes decorated by platinum catalyst nanoparticles—Examination and microanalysis using scanning and transmission electron microscopies

Carbon nanotubes (CNTs) decorated with platinum (Pt) nanoparticles (NPs) have been characterized using a cold field‐emission scanning electron microscope (SEM) and a high resolution field‐emission transmission electron microscope (TEM). With this particular composite material, the complementary nature of the two instruments was demonstrated. Although the long CNTs were found to be mostly bent and defective in some parts, the nucleation of Pt occurred randomly and uniformly covered the CNTs. The NPs displayed a large variation in size, were sometimes defective with twins and stacking faults, and were found to be faceted with the presence of surface steps. The shape and size of the NPs and the presence of defects may have significant consequences on the activity of the Pt catalyst material. Also, thin layers of platinum oxide were identified on the surface of some NPs.     

Ethanol extraction of red peppers: kinetic studies and microstructure

A three-parameter kinetic equation was developed for ethanol extraction of oleoresin from dry red peppers under different solute to solvent ratios, particle sizes and condition of structural damage. The model distinguished two main mechanisms of extraction: a fast, washing step and a diffusion-controlled process. Flaking and, to a lesser extent, blanching induced significant cellular damage resulting in more oleoresin being washed, a faster extraction rate and a higher final concentration in the solvent, compared to untreated material. The activation energy for extraction derived from the study was 6.1 kcal/mol, typical of diffusion-controlled processes. Light micrographs related microstructure to variations in extraction parameters.     

A PRACTICAL APPROACH TO PREPARATION AND MEAT PRESERVATION BY REFRIGERATION OR FREEZING OF THE LAND SNAIL (HELIX ASPERSA MÜLLER)

Helix aspersa Müller is one of the few land snails suitable for preparation for human consumption, and constitutes an important potential alternative for mass production of animal protein. High-quality meat obtained from this snail can compete with cattle, swine and poultry because of its comparatively lower production costs of infrastructure, labor and feeding. The objective of the study is to present information on initial processing steps for this product, where mucus ("slime") is eliminated from the snails. Concentrations of salt and vinegar over periods of time required for elimination of slime after the purging step were determined, permitting uninterrupted continuation of the preparation process before its refrigeration and freezing storage. Optimal slime elimination was achieved by following a statistical design based on a 2³ factorial scheme as a variable response to weight loss, indicating elimination of the slime. The results obtained showed the best concentration of salt to be 7.5% and vinegar 10%, with an immersion time of 45 min. Moreover, some preliminary aspects related to refrigeration and freezing rate process are also delivered.

PRACTICAL APPLICATIONS

The results of this study indicate that there is a practical way to eliminate the Helix aspersa Müller slime in order to obtain a cleaner meat, using acid salt solutions at room temperature with low-cost additives, including common salt and white vinegar, allowing the low- and median-capacity industries to have access to a simple technology in the preliminary operations of the production process. Furthermore, the product obtained could undergo the preservation processes with or without the shell, where the boiling-in-water operation could be included or not. Finally, it could be preserved by refrigeration or freezing.     

Expression of caveolin-1 in rat Leydig cells

Caveolin-1, the first member of caveolin family reported, is recognized as the structural component of caveola, a plasma membrane invagination or vesicles that are a subcompartment distinct from clathrin-coated pits. This protein is also known to be involved in cholesterol trafficking.
The aim of this study was to determine the expression of caveolin-1 in adult rat Leydig cells. Testis sections incubated with an antibody to caveolin-1 showed, by immunohistochemistry, a moderate number of Leydig cells with different degrees of immunoreaction and a strong reaction in endothelial cells and in the lamina propia of seminiferous tubules. Caveolin-1 was detected in the cell cytoplasm with a granular pattern and on the cell surface of Leydig cells cultured 24 h on uncoated, laminin-1 or type IV collagen coated coverslips. We also observed a milder reaction in 3 h cultures. Immunoreaction was also detected in Leydig cells with an antibody to tyrosine-phosphorylated caveolin-1. By double immunofluorescent technique, we observed co-localization of caveolin-1 and 3β-hydroxysteroid dehydrogenase. Western blot analysis revealed a band of about 22 kDa molecular weight that was recognized with both caveolin-1 and tyrosinephosphocaveolin-1 antibodies. Caveolin-1 is one of a few proteins with a demonstrated ability to bind cholesterol in vivo. In this context, the presence of caveolin-1 in Leydig cells may be related to cholesterol traffic -a rate limiting step in steroid biosynthesis.     

Double yield points in triblends of LDPE, LLDPE and EPDM

Factors that affect to the proposed mechanisms that produce the double yield phenomenon in semicrystalline polymeric materials were studied. The systems under study were ternary blends of low-density polyethylene (LDPE), linear LDPE (LLDPE) and ethylene propylene diene (EPDM). The influence on the yield mechanisms of the following different factors were analysed: processing conditions, composition, stretching rate, cooling conditions and different types of elastomers. The behaviour of these blends in the region where the double-yield points occur was found to be different for those LDPE-rich blends from those LLDPE-rich ones. These differences are explained in terms of the two mechanisms in the double yield phenomenon; that is, the slip of the crystalline blocks and the shear on the crystalline blocks. The stretching-rate effect is explained in terms of the stress relaxation time. The effects of EPDM content, cooling conditions and type of EPDM are found to be equivalent to a smaller stretching rate.     

EFFECT OF SOLID CONTENT AND SUGAR COMBINATIONS ON THE QUALITY OF SOYMILK-BASED YOGURT

A research to evaluate the effect of two levels of solids and two sugar combinations in the quality of a soymilk yogurt-type food was carried out. Yogurts were elaborated by inoculating lactic cultures ( Lactobacillus dellbruckii spp. bulgaricus and Streptococcus salivarius spp. thermophilus ) into soymilk with 8% and 11% solid levels and glucose/sucrose and glucose/fructose mixtures. Also, a control treatment with cow milk was prepared. Yogurts were analyzed after two days of preparation for their chemical (protein, lipids, titrable acidity and pH), physical (syneresis and viscosity) and sensory characteristics (quality and acceptability). Protein content of soymilk based yogurts ranged between 3.56 and 4.45 g/100 g. The higher titrable acidities (0.66% and 0.63% lactic acid) were shown by treatments with higher solids level, which also shown the lowest syneresis. All soymilk yogurts were yellowier than the control. The highest sensory acceptability was for the 8% solids treatment enriched with glucose and sucrose.

PRACTICAL APPLICATIONS

There are an increasing number of people suffering of lactose intolerance, which need an alternative product to milk. Besides, some people have adopted a strictly vegetarian way of life. Soymilk has been used for a long time by this part of the population; however, it usually has a beany flavor, which can cause some rejection among occidental consumers. A fermented product from soymilk, such as soymilk yogurt, may offer a good alternative for those people. In soymilk production it is necessary to carefully adjust the amount of solids and the sugar used in fermentation in order to obtain a well accepted commercial product. Soy yogurt could be used to formulate a number of different new products like desserts, high fiber yogurt, fruit-added yogurt and so on.