Knowledge Mining of Information Sources for Research in Construction Management

Extracting the right information at the right time is vital in any research project. Moreover, researchers generally seek innovative “knowledge mining” techniques for optimizing their research efforts within constrained time frames and with scarce resources. Meanwhile, rapid developments in the fields of computing and information technology drive the accelerated globalization process in both industry and academia. This paper explores some of the emerging technologies and associated research methodologies from an information supply chain perspective. An application in a recent Internet based two-phase questionnaire survey for design/build contractor selection provides a useful case study in the structuring of an innovative knowledge mining strategy. This experience feeds into the formulation of a “high-velocity” knowledge mining framework and a set of guidelines—to facilitate and enhance such innovative construction management research, while dealing with some initial issues/problems in the Internet based research environment. Furthermore, some critical success factors, key performance indicators, and mining strategies are consolidated for marshalling both vivid and tacit knowledge sources, such as by “exploiting” Internet resources for more creative and efficient construction management research.     

Investigation on combustion and emission characteristics of hydrogen-enriched dual-fuel engine operated under waste frying oil biodiesel

Using nonedible waste frying oil (WFO) as biodiesel and hydrogen in the mix composition may partly replace significant quantities of diesel fuel and help reduce fossil fuel reliance. The combination of diesel fuel, waste-fired biodiesel, and hydrogen gas can improve the performance, combustion, and emissions of single-fuel and dual-fuel diesel engines. This may lead to a novel alternative fuel mix pattern and modification for diesel engines, which is the research gap. Although there has been some research on waste-fired biodiesel and hydrogen gas-powered dual-fuel engines with the goal of partly replacing fossil fuels to a larger degree, there has been very little progress in this area. As a result, the current research effort focuses on using diesel fuel (100%, 30%, and 60%), waste-fired biodiesel (at 100%, 70%, and 40%), and hydrogen gas as fuel sources (5 and 10 liters per minute [LPM]). According to the current experiment, it was perceived in both dual-fuel and single-fuel modes. Under duel-fuel mode, the engine results for WFOB70D30 + H10 fuel blend had higher 4.2% (brake thermal efficiency [BTE]), 19.72% (oxides of nitrogen [NO_x]), and 9.09% (ignition delay [ID]) with a minimal range of (in-cylinder pressure, MFB, volumetric efficiency and heat release rate [HRR]) and a dropped rate of 4.34% (brake-specific energy consumption [BSEC]), 33.33% (carbon monoxide [CO]), 39.28% (hydrocarbons [HC]), 9.43% (smoke), and 6.97% (combustion duration [CD]) related to diesel fuel at peak load. However, single-fuel powered diesel engines provide minimal performance for the WFOB40D60 fuel blend with (11.32% lower BTE and 2.04% higher BSEC) and minimal rate of combustion (lower cylinder pressure, 2.12% minimal CD, 14.72% higher ID, minimal HRR combustion, volumetric efficiency, and MFB). Emitted fewer emissions (9.09% less CO, 4.87% less HC, 0.92% higher NO_x, and 1.69% more smoke) than diesel fuel at peak load. Therefore, it was concluded that adding 10 LPM of hydrogen gas to the biodiesel under a dual-fuel condition leads to better combustion, better performance, and less pollution than the single-fuel mode of operation.     

Ruthenium Pincer‐Catalyzed Cross‐Dehydrogenative Coupling of Primary Alcohols with Secondary Alcohols under Neutral Conditions

Cross‐dehydrogenative coupling of primary alcohols with secondary alcohols to obtain mixed esters with the liberation of molecular hydrogen is achieved in high yield and good selectivity under neutral conditions, using a bipyridyl‐based PNN ruthenium(II) pincer catalyst.     

Solution combustion synthesis and luminescent properties of perovskite red phosphors with higher CRI and greater lumen output

Two perovskite red phosphors, (La_0.96Eu_0.04)AlO₃ and (Y_0.96Eu_0.04)AlO₃ have been obtained by solution combustion method at 525 °C in less than 5 min. Formation of these phosphors has been characterized by powder XRD and luminescent properties. High exothermicity of the combustion process is sufficient enough for the formation and crystallization of the red phosphors. Luminescent properties of these red phosphors are quite different from other red phosphors.     

Comparative study on composition and antioxidant properties of mint and black tea extract

The antioxidant properties of plants could be correlated with oxidative stress defence in different human diseases. The present study was undertaken to evaluate and compare the antioxidant potential and the phytochemical composition in the aqueous extracts of mint leaves, black tea and black tea enriched with mint extract. All the three preparations exhibited free radical‐scavenging potential for nitric oxide (NO) radical, superoxide anion radical and hydroxyl radical, and the values were lesser than those of the antioxidants which acted as standards. In comparison, the mint extract exhibited higher free radical and NO scavenging effect. Hydroxyl radical and superoxide scavenging effects were more pronounced in tea with the mint extract, while the reducing power was exhibited more significantly by the black tea extract. The phytochemical compounds were identified and the total phenols and flavonoids were quantified and compared between these extracts.     

A support vector machine model for contractor prequalification

In complex and high value projects, prequalification is crucial for both contractors and clients, as it targets towards best value delivery through qualification safeguards and streamlined competition among potential candidates. Due the complex nature of the procurement problems such as prequalification exercises, the robust models are rarely attempted. The research reported in this paper presents an overview of potential suitability of Support Vector Machine (SVM) method for contractor/consultant prequalification transactions in the construction project procurements. Furthermore, the performance of SVM is compared with specific artificial neural network outcomes. The results obtained from practical datasets indicate encouraging potentials for SVM applications in the procurement problems such as prequalification and contractor selection. Hence, a SVM-based decision support framework is proposed.     

Mitochondrial membrane potential is a suitable candidate for assessing pollution toxicity in fish

Fish inhabiting polluted estuaries are highly exposed to severe stress characterized by an oxidant-antioxidant imbalance. The aim of the study was to explore the use of stress parameters such as adenosine triphosphate/adenosine diphosphate (ATP/ADP) ratio, mitochondrial membrane potential (?ψm) and total protein expression patterns as biomarkers against oxidant exposures in hepatocytes of Mugil cephalus living in either a contaminated (Test; Ennore) or uncontaminated (Control; Kovalam) estuary. Earlier, the pollutant stress impact was determined through light and electron microscopy studies. The ATP/ADP ratio was measured using high performance liquid chromatography; ?ψm by fluorescent probe 5, 5′, 6, 6′-tetrachloro-1, 1′, 3, 3′-tetraethyl benzimidazolcarbocyanine iodide (JC-1) dye and total protein expression patterns by protein profiling. The preponderance of stress impact was confirmed through microscopy studies that featured cytological alterations, disturbances in the surface morphology and in the cell organelles at the ultrastructural levels. Hepatocytes of test fish demonstrated a decrease in ATP and an increase in ADP and thereby alteration in ATP/ADP ratio (p < 0.05; 20.75%). A significant disturbance (p < 0.05; 26.57%) in ?ψm with a ratio of J-aggregates/JC-1 monomer of 1 was observed for test fish hepatocytes compared to control group with a J-aggregates/JC-1 monomer ratio of 1.5. Quantitative assessment of protein expression levels also revealed enhanced induction of both low and high molecular weight proteins in test fish hepatocytes. The findings highlight the use of these parameters as the highly sensitive biomarkers in response to contaminant exposure compared to the routinely used antioxidant and oxidant stress parameters in biomonitoring programs. Among the measured parameters, the determination of ?ψm may be suggested as a novel candidate as a biomarker because of its greater specificity and rapid quantitative risk assessment of pollutant exposures.     

Formation of Tertiary Amides and Dihydrogen by Dehydrogenative Coupling of Primary Alcohols with Secondary Amines Catalyzed by Ruthenium Bipyridine‐Based Pincer Complexes

Dehydrogenative coupling of primary alcohols with secondary amines to form tertiary amides and dihydrogen (H₂) is efficiently catalyzed by bipyridyl‐based ruthenium pincer complexes (0.2–1 mol%) under neutral conditions (in case of the dearomatized complexes), or with added catalytic amount of base. The reaction is sensitive to steric hindrance; in the case of amidation of bulky secondary amines a less sterically hindered complex is more efficient. Selective acylation of primary amines in the presence of secondary amines was also demonstrated.

     

A New Architecture for Adaptive Intrafield Transform Compression of NTSC Composite Video Signal

In orthogonal transform coding of NTSC video signal, the data are processed in blocks. Processing a block of data that is maximally correlated leads to larger compression. This correspondence describes a new architecture for arranging the pixels in a block that yields higher correlation than the adjacent pixel blocks. The data are processed using adaptive, intrafield, discrete cosine transform, variable bit allocation coding. In subjective tests good quality pictures were obtained for an average of about 2 bits/pel for intrafield processing.     

Preparation,characterizations, and antibacterial properties of Cu/SnO<Subscript>2</Subscript> nanocomposite bilayer coatings

A nano-bilayer structure consisting of copper and SnO₂ nanocomposites was prepared by a magnetron sputtering method. A nano-SnO₂ thin layer with a thickness of 52 nm was achieved on quartz glass. A nano-copper layer was then deposited on top of the SnO₂ thin layer by the sputtering method. The thickness of the nano-copper layer was approximately 7 nm, such that the SnO₂ layer was not only completely covered by the copper layer but it also resulted in transparent bilayer films. Post-annealing was carried out at 400°C in air for 1 h to obtain a crystalline SnO₂ phase and simultaneously the copper layer was oxidized to CuO. Sputtered nanocomposites of CuO/SnO₂ bilayer films showed a synergistic effect toward E. coli inactivation under indoor light exposure. A possible mechanism for the synergistic effect with respect to the antibacterial properties of CuO/SnO₂ bilayer nanocomposites has been proposed. Incorporating CuO onto the SnO₂ layer achieves photocatalyst works under indoor light and provides an antimicrobial function even under a dark environment by the antimicrobial property of CuO itself. Reported CuO/SnO₂ sputter coating can be useful to apply, for instance, to electric devices such as touch panel displays in a hospital in order to reduce hospital-acquired infections (HAIs).