Computerized Time Impact Analysis for Project Acceleration

Abstract: Project acceleration often results in claims. A LISP program for performing time impact analysis for project acceleration is presented. The program helps the user identify the number of days by which the project can be accelerated and what the user's share will be of the acceleration costs involved. The program analyzes the as-planned, as-built, and utility data files submitted by the user and identifies all delayed, accelerated, added, and canceled (DAAC) activities. It then generates as-planned, as-built, projected, adjusted, owner-accountable, and contractor-accountable schedules. The program performs a compression analysis on the remaining portion of the project. After a consultation session with the user, it apportions acceleration costs between the owner and the contractor in an equitable way. This program is expected to help settle claims.     

Microhardness profile prediction of a graded steel by strain gradient plasticity theory

In the present study, the Vickers microhardness profile of functionally graded steel austenitic steel produced by electroslag remelting process has been investigated. To produce functionally graded steels, two different slices from plain carbon steel and austenitic stainless steels were spot welded and used as electroslag remelting electrode. Functionally graded steel containing graded layers of austenite may be fabricated via diffusion of alloying elements during remelting stage. Vickers microhardness profile of the specimen has been obtained experimentally and modeled with mechanism-based strain gradient plasticity theory. In this regard, the density of the statistically stored dislocations and that of geometrically necessary dislocations was related to the Vickers microhardness profile of each layer. The experimental results are in good agreement with those obtained from the theory.     

Deinking in bubble column and airlift reactors: Influence of wastewater of Merox unit as pulping liquor

Deinking efficiency of recycled fibers was investigated in bubble column reactor (BCR) and in internal loop airlift reactor (ALR). The brightness and intensity of ink spot of deinked fibers were reported as deinking efficiencies. A four-step process involving pulping, washing, flotation, and secondary washing was used. Employing ALR instead of BCR resulted in an increase of 1–4% in brightness, and a decrease of 3–14% in number of ink spot. Subsequently, in separate experiment the wastewater obtained from a Merox unit was used in pulping step instead of sodium hydroxide solution as pulping liquor. Compared to sodium hydroxide, industrial wastewater rendered more brightness gain. Comparison of both experiments suggests that using industrial wastewater in the pulping step and ALR in flotation step gives satisfactory results for industrial applications, yields a quality product with reduced capital investment and operation costs while considerably preserving the environment.     

Modification of electrophoretically deposited nano-hydroxyapatite coatings by wire brushing on Ti–6Al–4V substrates

In the present study, after successful synthesis of nano-HA powders by chemical precipitation method, wire-brushing (WB) treatment was effectively employed on Ti–6Al–4V substrates for the modification of electrophoretically deposited nano-hydroxyapatite coatings. The precipitated nano-HA particles were characterized by XRD, FT-IR, and DLS analyses. The morphology and particle size of synthesized nano-HA particles was observed by FE-SEM. The Ti–6Al–4V plates were initially wire brushed at different times and rotational speeds. Microhardness profile and AFM analysis of substrates were then studied. It was found that WB treatment at 16,000 rpm for 60 s leads to a maximum enhancement in the hardness and roughness of surface. Then, the electrophoretic deposition of nano-HA particles was carried out at constant voltage of 30 V and after 60 s. The results of adhesion test and potentiodynamic polarization measurements showed that WB treatment on Ti–6Al–4V substrates could efficiently increase the bonding strength between coating and substrate as well as corrosion resistance.     

Analysis of Bridge Condition Rating Data Using Neural Networks

Currently bridges are evaluated using either a visual inspection process or a detailed structural analysis. When bridge evaluation is conducted by a visual inspection, a subjective rating is assigned to a bridge component. With analytical evaluation, the rating is computed based on the load applied and the resistance of the bridge component. There have been several attempts to correlate the subjective rating to the analytical rating. The conventional statistical analyses, as well as methods based on fuzzy logic, have not been very successful in providing a clear relationship between the two rating systems. This paper describes the application of neural network systems in developing the relation between subjective ratings and bridge parameters as well as that between subjective and analytical ratings. It is shown that neural networks can be trained and used successfully in estimating a rating based on bridge parameters. The specific application problem for railroad bridges in the commuter rail system in the Chicago metropolitan area is presented. The study showed that a successful training of a network can be achieved, especially if the input data set contains parameters with a diverse combination of intercorrelation coefficients. When the relationship between the bridge subjective rating and bridge parameters was investigated, the network had a prediction rating of about 73%. The study also investigated the relation between the subjective and analytical rating. In this case, the prediction rate was about 43%. Compared with conventional statistical methods and the fuzzy‐logic approach, the neural network system had a much better performance ratio in establishing the relation between the bridge rating and bridge parameters.     

Spectrofluorimetric determination of buparvaquone in biological fluids,food samples and a pharmaceutical formulation by using terbium–deferasirox probe

A simple spectrofluorimetric method is described for the determination of buparvaquone (BPQ), based on its quenching effect on the fluorescence intensity of Tb³⁺–deferasirox (DFX) complex as a fluorescent probe. The excitation and emission wavelengths were 328 and 545 nm, respectively. The optimum conditions for determination of BPQ were investigated considering the effects of various affecting parameters. The variations in fluorescence intensity of the system showed a good linear relationship with the concentration of BPQ in the range of 10–1500 μg L⁻¹, its correlation coefficient was 0.999 with the detection and quantification limits of 1.1 and 3.4 μg L⁻¹, respectively. Linearity, reproducibility, recovery, limits of detection and quantification made the method suitable for BPQ assay in biological fluids, meat, dairy products and BPQ parenteral solutions (vials). The method was applied to real samples of serum and milk of three cows receiving BPQ.     

Spectrofluorimetric determination of tin in canned foods

A simple and sensitive spectrofluorimetric method for the determination of tin as its complex with 1-(2-pyridylazo)-2-naphtol (PAN) in a mixed micellar medium was developed. The mixture of a non-ionic surfactant, Triton X-100 and an anionic surfactant, bis(2-ethylhexyl) sulfosuccinate (AOT) was used as a suitable micellar medium for solubilizing of complex and ligand and also for enhancing the fluorescence intensity of complex. In the optimum experimental conditions the maximum excitation and emission wavelengths of Sn-PAN complex were 300 and 360 nm, respectively. The calibration graph was linear in the range of 0.01-0.8 microg ml(-1) with a correlation coefficient of 0.9991. The detection limit was found to be 2 ng ml(-1). The relative standard deviation of the method for the determination of 0.1 microg ml(-1) tin was calculated to be 0.74%. The interferences caused by the presence of a number of common cations and anions were studied. Finally, the method was successfully applied to the determination of tin in various canned products.     

An investigation on the physicochemical characterization of interesterified blends of fully hydrogenated palm olein and soybean oil

In this study, the effect of interesterification (using sodium methoxide) on physicochemical characteristics of fully hydrogenated palm olein (FHPO)/soybean oil blends (10 ratios) was investigated. Interesterification changed free fatty acid content, decreased oil stability index, solid fat content (SFC) and slip melting point (SMP), and does not affected the peroxide value. With the increase of FHPO ratio, oil stability index, SFC and SMP increased in both the interesterified and non-interesterified blends. Fats with higher FHPO ratio had narrower plastic range, as well. Compared to the initial blends, interesterified fats had wider plastic ranges at lower temperatures. Both the non-interesterified and interesterified blends showed monotectic behavior. The Gompertz function could describe SFC curve (as a function of temperature, saturated fatty acid (SFA) content or both) and SMP (as a function of SFA) of the interesterified fats with high R² and low mean absolute error.     

Ethyl cellulose/hydroxypropyl methyl cellulose-based oleogel shortening: Effect on batter rheology and physical properties of sponge cake

This study attempts to fill the gap in ongoing research on the design, optimization, and characterization of ethyl cellulose/hydroxypropyl methyl cellulose-based (EC/HPMC-based) low-saturated oleogel-shortenings by examining their functional effects on physicochemical, and rheological properties in the cupcake and its batter. Thus, the commercial shortening was completely replaced with the oleogel-shortenings in the cake formulation and, then, characteristics of the batter (including specific gravity, emulsion stability, and rheological properties), and cake samples (specific volume, moisture content, and texture properties) were evaluated and compared with each other and the control samples (containing commercial-shortening). In short, the EC-based- and EC/HPMC-based-oleogel-shortenings-batters had more specific gravity and emulsion stability than the control-batter. Liner viscoelastic rang in EC/HPMC-based-oleogel-shortenings-batter, EC-based-oleogel-shortenings-batter, and control-batter was 0.212%, 0.159%, and 0.195%, respectively. EC/HPMC-based-oleogel-shortenings-batter had a more viscoelastic behavior than EC-based-oleogel-shortening-batter after the control-batter (p < 0.05). The results of frequency sweep and dynamic shear tests indicated a higher similarity of the rheological behavior of the EC/HPMC-based-oleogel-shortening-batter with the control-batter. The results of moisture content and texture profile analysis of the cake samples indicated a slower staling in the oleogel-shortenings containing samples, especially EC/HPMC-based-oleogel-shortening type.