Costs and Benefits of MBE Rules in Construction

The findings of a study designed to investigate the costs and benefits of Minority Business Enterprise (MBE) regulations in the construction industry are presented. The data indicate that large contractors have less difficulty than smaller organizations in meeting MBE requirements. In addition, it is shown that the regulations both benefit and enlarge the number of minority contractors. According to the study, however, MBE procedures have not increased the number of qualified minority contractors. The data also indicate that MBE regulations have increased the cost of construction projects. The amount allocated, although significant when compared to percentage profit, is not substantial. For example, the unweighted values, in terms of construction dollar volume, range from 3.41% for the Engineering News‐Record (ENR) 400 organizations to 3.33% for the Associated General Contractors of Indiana, AGC (Indiana). The weighted values range from 2.04% for the ENR 400 contractors, to 3.74% for the AGC (Indiana). The great majority of firms surveyed indicate that MBE rules and regulations should be modified. Better agency procurement efforts and comprehensive programs to train minority contractors are mentioned as a necessity.     

Adsorption and desorption dynamics of associative polymers onto particulates of titanium dioxide,alumina and quartz

The authors have been investigating the adsorption and desorption dynamics of nonionic water soluble polymers on inorganic particles. The influence of the nature of polymers with and without associating hydrophobic end groups, the nature of adsorbents [TiO₂, Al₂O₃ (neutral, acid and basic), and SiO₂], polymer concentrations, linear velocity of fluids, and mutual diffusion of polymer molecules on the patterns of adsorption and desorption distribution of polymer concentrations are shown. The model polymer is a nonionic polyurethane polymer based on ethylene oxide. The polymer's structure is R-O-(DI-PEO)₆-DI-O-R (R is C₁₆H₃₃, DI is isophorone diisocyanate, and PEO is CARBOWAX^TM with a molecular weight of 8200). The phenomenological models of association and dissociation kinetics of associative polymers are suggested. The half-lives of clusters into adsorption and desorption layers are estimated. It is shown that heats of desorption of associative polymers are dependent essentially on heats of dissociation of clusters.     

Exhaust emissions and electric energy generation in a stationary engine using blends of diesel and soybean biodiesel

The present work describes an experimental investigation concerning the electric energy generation using blends of diesel and soybean biodiesel. The soybean biodiesel was produced by a transesterification process of the soybean oil using methanol in the presence of a catalyst (KOH). The properties (density, flash point, viscosity, pour point, cetane index, copper strip corrosion, conradson carbon residue and ash content) of the diesel and soybean biodiesel were determined. The exhaust emissions of gases (CO, CO₂,C_xH_y,O₂, NO, NO_x and SO₂) were also measured. The results show that for all the mixtures tested, the electric energy generation was assured without problems. It has also been observed that the emissions of CO, C_xH_y and SO₂ decrease in the case of diesel–soybean biodiesel blends. The temperatures of the exhaust gases and the emissions of NO and NO_x are similar to or less than those of diesel.     

Submicron particle size and polymerization excess surfactant analysis by capillary hydrodynamic fractionation (CHDF)

The particle size distribution of a blend of two polymer latex monodisperse standards, 86 and 238 nm, has been measured by capillary hydrodynamic fractionation (CHDF). The particle size distributions obtained agreed well with the expected particle diameters. The relative amounts of the two standards in the blends were accurately measured at different blend ratios. The particle size distribution of a parenteral lipid sample was successfully measured. A soluble species was fractionated from latex standards smaller than 100nm. This soluble species appears to be excess surfactant used in the preparation of small size monodisperse latexes. The amount of excess surfactant increases as the particle diameter of the standard decreases.     

Soldering mechanisms in materials and coatings for aluminum die casting

The stability against reaction with aluminum of materials and coatings commonly used in aluminum die casting was investigated. The materials considered here were H13 tool steel and Anviloy® 1150, whereas the coatings were TiN and CrN. Special model, freestanding, multilayered thin film structures were used in this study, in association with complementary differential scanning calorimetry and X-ray diffraction. The nature of the reactions (endo or exothermic) and their onset temperatures up to 1273 K were determined. Based on of these results, some activation energies for the different reactions taking place between aluminum and die material or between aluminum and coatings could be established. Different intermetallic compounds were formed in these reactions, which were identified by post mortem X-ray diffraction analysis. Anviloy® 1150 showed superior stability as compared to H13 tool steel, whereas CrN was more inert than TiN coatings. CrN exhibited the best performance among all materials and coatings considered here, although its practical application relies also on adhesion of the CrN coating to the die bulk material. The results are discussed on the lights of two recent models for soldering in aluminum die casting.     

Survival of Listeria innocua in Minas Traditional Serro cheese during ripening

Cheese produced with raw milk can be a risk to consumer health. It is known that lactic acid bacteria present in raw milk and in natural starters can produce antimicrobial compounds against some foodborne bacteria. This work aimed to evaluate the survival of Listeria innocua in Minas Traditional Serro cheese during cheese ripening. The cheeses were inoculated with 10¹, 10² or 10³ CFU mL⁻¹ of the bacterium and were analyzed for 60 days of ripening at 30 °C. It was observed that the time and the dose of bacteria inoculated affected (p < 0.05) the survival of L. innocua. Even when the lowest dose was inoculated, at the end of the 60 days, approximately 10² CFU mL⁻¹ of L. innocua was detected in the cheese. The lactic acid bacteria present in the milk and in the natural starter were not sufficient to guarantee the absence of L. innocua in Minas Traditional Serro cheese even after 60 days of storage, as is required by Brazilian legislation.     

Crops that feed the world 4. Barley: a resilient crop? Strengths and weaknesses in the context of food security

Barley is cultivated both in highly productive agricultural systems and also in marginal and subsistence environments. Its distribution is worldwide and is of considerable economic importance for animal feed and alcohol production. The overall importance of barley as a human food is minor but there is much potential for new uses exploiting the health benefits of whole grain and beta-glucans. The barley supply chains are complex and show added value at many stages. Germplasm resources for barley are considerable, with much potential for exploitation of its biodiversity available through the use of recently developed genomic and breeding tools. Consequently, substantial gains in crucial sustainability characteristics should be achievable in the future, together with increased understanding of the physiological basis of many agronomic traits, particularly water and nutrient use efficiency. Barley’s ability to adapt to multiple biotic and abiotic stresses will be crucial to its future exploitation and increased emphasis on these traits in elite germplasm is needed to equip the crop for environmental change. Similarly, resource use efficiency should become a higher priority to ensure the crop’s sustainability in the long-term. Clearly barley is a resilient crop with much potential which can be realised in the future.     

Experience-Based Cognition for Driving Behavioral Fingerprint Extraction

Abstract

With the rapid progress of information technologies, cars have been made increasingly intelligent. This allows cars to act as cognitive agents, i.e., to acquire knowledge and understanding of the driving habits and behavioral characteristics of drivers (i.e., driving behavioral fingerprint) through experience. Such knowledge can be then reused to facilitate the interaction between a car and its driver, and to develop better and safer car controls. In this paper, we propose a novel approach to extract the driver’s driving behavioral fingerprints based on our conceptual framework Experience-Oriented Intelligent Things (EOIT). EOIT is a learning system that has the potential to enable Internet of Cognitive Things (IoCT) where knowledge can be extracted from experience, stored, evolved, shared, and reused aiming for cognition and thus intelligent functionality of things. By catching driving data, this approach helps cars to collect the driver’s pedal and steering operations and store them as experience; eventually, it uses obtained experience for the driver’s driving behavioral fingerprint extraction. The initial experimental implementation is presented in the paper to demonstrate our idea, and the test results show that it outperforms the Deep Learning approaches (i.e., deep fully connected neural networks and recurrent neural networks/Long Short-Term Memory networks).     

Enhanced visualization of histological samples with an adjustable RGB contrast system with application for tissue used in photodynamic therapy

The analysis of histological sections has long been a valuable tool in the pathological studies. The interpretation of tissue conditions, however, relies directly on visual evaluation of tissue slides, which may be difficult to interpret because of poor contrast or poor color differentiation. The Chromatic Contrast Visualization System (CCV) combines an optical microscope with electronically controlled light-emitting diodes (LEDs) in order to generate adjustable intensities of RGB channels for sample illumination. While most image enhancement techniques rely on software post-processing of an image acquired under standard illumination conditions, CCV produces real-time variations in the color composition of the light source itself. The possibility of covering the entire RGB chromatic range, combined with the optical properties of the different tissues, allows for a substantial enhancement in image details. Traditional image acquisition methods do not exploit these visual enhancements which results in poorer visual distinction among tissue structures. Photodynamic therapy (PDT) procedures are of increasing interest in the treatment of several forms of cancer. This study uses histological slides of rat liver samples that were induced to necrosis after being exposed to PDT. Results show that visualization of tissue structures could be improved by changing colors and intensities of the microscope light source. PDT-necrosed tissue samples are better differentiated when illuminated with different color wavelengths, leading to an improved differentiation of cells in the necrosis area. Due to the potential benefits it can bring to interpretation and diagnosis, further research in this field could make CCV an attractive technique for medical applications.