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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2009.07.004 Byline: M.K. Tiwari (a), N. Raghavendra (a), Shubham Agrawal (b), S.K. Goyal (c) Keywords: Supply chain design; Optimization; Taguchi; Artificial Immune System; Heuristic Abstract: Supply chain network design is considered a strategic decision level problem that provides an optimal platform for the effective and efficient supply chain management. In this research, we have mathematically modeled an integrated supply chain design. To ensure high customer service levels, we propose the inclusion of multiple shipping/transportation options and distributed customer demands with fixed lead times into the supply chain distribution framework and formulated an integer-programming model for the five-tier supply chain design problem considered. The problem has been made additionally complex by including realistic assumptions of nonlinear transportation and inventory holding costs and the presence of economies of scale. In the light of aforementioned facts, this research proposes a novel solution methodology that amalgamates the features of Taguchi technique with Artificial Immune System (AIS) for the optimum or near optimum resolution of the problem at hand. The performance of the proposed solution methodology has been benchmarked against a set of test instances and the obtained results are compared against those obtained by Genetic Algorithm (GA), Hybrid Taguchi-Genetic Algorithm (HTGA) and AIS. Simulation results indicate that the proposed approach can not only search for optimal/near optimal solutions in large search spaces but also has good repeatability and convergence characteristics, thereby proving its superiority. Author Affiliation: (a) Department of Industrial Engineering and Management, Indian Institute of Technology, Kharagpur 721 302, India (b) Operations Research and Industrial Engineering, Department of Mechanical Engineering, University of Texas at Austin, Austin, TX 78705, USA (c) Decision Sciences and MIS, John Molson School of Business, Concordia University, West Montreal, Quebec, Canada Article History: Received 18 October 2007; Accepted 10 July 2009 more...

• The corrosion inhibition property of AH extract was examined through chemical and electrochemical techniques. • The presence of functional groups in the AH extract was confirmed by Fourier transform infrared spectrophotometer. • Scanning electron microscopy (SEM) technique was used in order to confirm the absence of corrosion products in inhibited system. The sustainable corrosion impediment of tactic central materials such as mild steel and copper is the subject of utmost importance in contemporary civilization due to their wide spread utility in industrial sectors. This part reports the outcome of chemical (weight loss) and electrochemical measurements on the inhibition of corrosion of mild steel and copper metals in both 0.5 M HCl and 0.5 M NaOH media. Weight loss measurements divulged that, corrosion protection efficiencies were enhanced with increment in the concentration of plant extracts which indicates that dissolution process was stifled; whilst a decrease was noticed with the rise of solution temperature at habitual acid and base concentration is plausible due to thermal agitation of plant extract constituents from the metal surfaces. The maximum protection efficiency observed with immersion period of one hour at 303 K. (93.750% for copper in acid medium, 90% for copper in alkali medium, 93.478% for MS in acid medium and 91.66% for MS in alkali medium). The probable inhibitive modality mechanism of most potent green inhibitor was further corroborated by kinetic and thermodynamic models. Electrochemical studies like, Tafel plot and AC impedance studies were used for appraising the green inhibitor behavior. The Tafel plot studies shows that, AH extract act as mixed type corrosion inhibitor for copper in acid media, mild steel in acid and alkali media, whereas AH extract act as anodic type corrosion inhibitor for copper in alkali media. The results of chemical and electrochemical techniques proved that, tender arecanut husk (AH) extract was the most efficacious eco-friendly corrosion inhibitor for mild steel and copper metals in both HCl and NaOH media with a concentration-dependent mode. Surface depiction via scanning electron microscopy (SEM) technique surmised the dearth of corrosion products and topographic amendment of the studied metals. Therefore, technological and economic profit is envisaged from an affirmative result in this study. [ABSTRACT FROM AUTHOR] more...

Nanoclay dispersed polymer composites possess high specific stiffness and strength measured in-plane. Such composites can withstand out-of plane low-energy impacts, wear, abrasion and erosion. This paper reports the effect of nanoclay addition on particle impact erosion behaviour of glass / vinylester composites using Taguchi's Orthogonal Array technique. Erosion tests were conducted using silica sand particles of size 177 to 595 μm. The results showed that addition of nanoclay up to 3 wt. % reduced the erosion rate of the composites. Impingement angle, particle size, stand- off-distance and velocity of impact showed decreasing order of significance and the erosion was in the range 292.5 to442.5 mg/kg. Morphology of the eroded surface was examined using Scanning Electron Microscopy. Erosion rate was maximum at normal impact angles with crater formation. [ABSTRACT FROM AUTHOR] more...

Transition metal ferrites are the essential components utilized in the latest modern-day technology and these include greater elements whose oxidation states and ionic radii are important for exploring their magnetic, optical, structural, and electrochemical properties. The present investigation was targeted on the preparation, physical and electrochemical characterizations of Co-doped MnFe 2 O 4 nanomaterials such as 2 wt% Co-doped MnFe 2 O 4 , 4 Wt.% Co-doped MnFe 2 O 4 , and 8 Wt.% Co-doped MnFe 2 O 4. More specifically, the study will focus on the techniques which have been employed to raise the specific capacitance of the metal oxides. Electrochemical properties such as cyclic voltammetry (CV), potentiostatic and impedance were used to analyse the super capacitive performance of Co-doped MnFe 2 O 4 electrodes. Based on the outcomes, it is determined that 2 wt% of Co-doped MnFe 2 O 4 has higher super capacitive behaviour than different samples. Precise capacitance for this nanocomposite from GCD was determined to be 551.39 F/g at a current density of 1 mA/cm2. Accordingly, Co-doped MnFe 2 O 4 may be utilized as a promising electrode for energy storage applications. It could be believed that this form of composites indicates excellent capability as electrochemical supercapacitors. Image 1 [ABSTRACT FROM AUTHOR] more...

The present irrigation and nutrient management practices could stabilize crop yields, but the huge energy consumption and GHG emissions put pressure on environmental quality. Therefore, climate-smart irrigation and nutrient management strategies are essential for sustainable fodder maize seed production systems. To address this research gap, climate-smart irrigation and nutrient management strategies were evaluated to reduce the environmental impact, increase profitability, reach carbon neutrality, and to achieve sustainable development goals such as improving energy productivity (SDG 7) and reductions in CO 2 emissions (SDG 13) by 2030 to achieve global climate goals. The results from this study revealed that direct renewable resources were the major contributors to overall carbon (72.37%) and energy (24.77%) consumptions. Moderate irrigation at 50% depletion saved 19.11% energy and 26.11% carbon inputs by conserving water, fossil fuels, and manpower and was found to be more energy efficient (21.5% higher), less energy intensive (42.36 MJ US$−1), and with the lowest carbon footprint (0.34 kg CE kg−1 grain) over full irrigation. The adequate nutrients (Nitrogen 120: Phosphorus 60: Potassium 40 + Zinc 20 kg ha−1) resulted in improved energy use efficiency (6.24), carbon efficiency (16.02), and overall biomass yield (13.29 t ha−1). Therefore, the combination of climate-smart 50% deficit irrigation and adequate nutrients had a higher energy profitability (6.69), carbon output (86 486 kg ha−1), carbon efficiency (18.11), and carbon sustainability index (17.11). In conclusion, fodder maize seed production in semi-arid environments is economical, sustainable, energy efficient, and environmentally beneficial when using climate-smart 50% deficit irrigation and adequate nutrients. [Display omitted] • Deficit irrigation reduced diesel use; 57.50%, water; 30.48%, and labour; 21.05%. • Deficit irrigation saved 19.11% of the total energy and 26.11% of the C inputs. • Deficit irrigation and adequate nutrients improved maize seed yield and profitability. • Climate-smart practices reduced energy demand and CO 2 emissions (26.08%). [ABSTRACT FROM AUTHOR] more...

This paper presents long term durability prediction of 0–5 wt.% nanoclay/vinylester/glass fibre nanocomposites based on their tensile strength retention in accelerated hygrothermal ageing using Arrhenius rate model. The specimens were exposed to 30 °C, 50 °C and 60 °C and 95% relative humidity for 75 days and tested for tensile strength retention as a function of duration of exposure. The predicted tensile strength retentions for one year of ageing of vinylester/glass at 30 °C, 50 °C and 60 °C using Arrhenius rate model were 59%, 48% and 43% respectively. The corresponding strength retentions predicted for 4 wt.% nanoclay/vinylester/glass were 81.1%, 77.9% and 76.4%. Strength retentions for ten years were predicted using the analytical model to assess their long-term performance. [ABSTRACT FROM AUTHOR] more...