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Purpose - Diesel engine can produce power more efficiently with lower exhaust emissions when operated at optimum input parameter settings. To achieve this goal, the purpose of this paper is to optimize the input parameters of dies...
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Purpose - Diesel engine can produce power more efficiently with lower exhaust emissions when operated at optimum input parameter settings. To achieve this goal, the purpose of this paper is to optimize the input parameters of diesel engine which will lead to optimum performance and exhaust emissions. Design/methodology/approach - To achieve the goal of improving diesel engine performance and exhaust emissions, four input parameters were considered in the study. Five different levels of each input parameter were taken. Four response variables under no load, half load and full load conditions were recorded. Experiments were performed in random manner according to selected Taguchi L25 orthogonal array. The data were analyzed using grey relational analysis coupled with principal component analysis. Analysis of S/N ratio was performed to obtain the optimum combination of input parameters. The grey relational grade at optimum setting of the input parameters was obtained by regression analysis. Findings - Results of the current research work give the optimum input parameter settings for no load, half load and full load conditions of diesel engine. Engine produces power more efficiently with low exhaust emissions when operated at these optimum settings. Practical implications - In view of the compliance to the stringent air pollution norms of the nations and fast depleting fossil fuels, it is of the utmost importance to design and operate the engine in the optimum range of its input parameters so that it produces more power with low exhaust emissions. This paper aims at optimizing input parameters of diesel engine to improve performance and exhaust emissions. Results of the study presented in this paper are significantly useful for diesel engine-related researchers and professionals. Originality/value - From the literature review, it appears that only few researchers have conducted studies pertaining to the optimization of the input parameters of diesel engine to improve performance or exhaust emissions. Although few studies related to the optimization of compression ratio, fuel injection timing, fuel injection pressure and air pressure have been reported, no work related to optimization of temperature and pressure of turbocharged air has been reported. Therefore, the main focus of the current research work is on optimizing the charge air temperature and pressure with respect to performance and exhaust emissions.
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In the present study, butt joints of aluminum (Al) 8011-H18 and pure copper (Cu) were produced by friction stir welding (FSW) and the effect of plunge depth on surface morphology, microstructure and mechanical properties were inve...
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In the present study, butt joints of aluminum (Al) 8011-H18 and pure copper (Cu) were produced by friction stir welding (FSW) and the effect of plunge depth on surface morphology, microstructure and mechanical properties were investigated. The welds were produced by varying the plunge depth in a range from 0.1 mm to 0.25 mm. The defect-free joints were obtained when the Cu plate was fixed at the advancing side. It was found that less plunging depth gives better tensile properties compare to higher plunging depth because at higher plunging depth local thinning occurs at the welded region. Good tensile properties were achieved at plunge depth of 0.2 mm and the tensile strength was found to be higher than the strength of the Al (weaker of the two base metals). Microstructure study revealed that the metal close to copper side in the Nugget Zone (NZ) possessed lamellar alternating structure. However, mixed structure of Cu and Al existed in the aluminum side of NZ. Higher microhardness values were witnessed at the joint interfaces resulting from plastic deformation and the presence of intermctallics.
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Purpose - Higher level of customer satisfaction for halal products can be achieved by the effective adoption of halal certification through assessment and accreditation (HCAA). There are certain issues that seem detrimental toward...
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Purpose - Higher level of customer satisfaction for halal products can be achieved by the effective adoption of halal certification through assessment and accreditation (HCAA). There are certain issues that seem detrimental towards the adoption of HCAA. The purpose of this paper is to identify the major barriers towards the adoption of HCAA and evaluate inter-relationships among them for developing the strategies to mitigate these barriers. Design/methodology/approach - The barriers towards the adoption of HCAA are identified through an integrative approach of literature review and expert's opinion. The inter-relationship among the identified barriers is evaluated using fuzzy-based decision-making trial and evaluation laboratory (fuzzy DEMATEL) technique, which categorises them into influential and influenced group. Findings - The evaluation of inter-relationship among barriers using fuzzy DEMATEL indicates four influencing barriers and six influenced barriers towards the adoption of HCAA. Further, findings suggest an extensive government, and management support is vital in terms of commitment, resources and actions to realise the benefits attributed with HCAA. Research limitations/implications - The inter-relationship among barriers is contextual and based on the perception of experts which may be biased as per their background and area of expertise. This study pertains to a specific region and can be extended to the generalised certification system. Originality/value - The empirical base of the research provides the inter-relationship among the barriers towards the adoption of HCAA which can be effectively used as input in the decision-making process by producers, manufacturers and distributor. The policy maker can analyse the cause group and effect group of barriers to formulate policies that would help in the adoption of HCAA.
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This research work deals with the optimisation of controllable parameters of the organic Rankine cycle (ORC) run by waste heat. Performance measures have been evaluated for different waste heat temperatures, condenser temperatures...
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This research work deals with the optimisation of controllable parameters of the organic Rankine cycle (ORC) run by waste heat. Performance measures have been evaluated for different waste heat temperatures, condenser temperatures, refrigerants and mass flow rate. The design of experiment was performed on the L9 orthogonal array of Taguchi's method. Three performance measures such as thermal efficiency, exergy destruction rate and the work output were used for the assessment and optimisation of the cycle. An optimum combination of parameters obtained by Taguchi's method is compared with analytical results. The comparison suggests that the variance of results is within the desired level of confidence. Individual effect of parameters on the performance of ORC is also estimated using analysis of variance. Turbine inlet temperature has large effects on efficiency and work output. Mass flow rate of the refrigerant has the largest effect on the exergy destruction rate.
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An experimental investigation of a Y-shaped diffusing duct with an aspect ratio and area ratio of 2 and turning angle of 22.5722.5° is reported for flow and performance characteristics. A calibrated five-hole pressure probe in nu...
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An experimental investigation of a Y-shaped diffusing duct with an aspect ratio and area ratio of 2 and turning angle of 22.5722.5° is reported for flow and performance characteristics. A calibrated five-hole pressure probe in null mode is used to measure the flow parameters. The performance parameters are evaluated based on mass-averaged quantities. It is observed that the static pressure recovery coefficient and the total pressure loss coefficient increase continuously up to the exit of the diffusing duct at a constant rate. It is also observed that the flow is divided into two flow regimes whereas at the merger, the two streams mixed with each other resulting a centrally core flow with almost uniform intensity and a pair of vortices. The longitudinal velocity distribution at the exit is seen to be nearly uniform.
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The present work seeks to assess the sustainability of different solar photovoltaic (SPV) electricity-generating systems based upon energy, environment and economics. The sustainability indicators evaluated for energy, environment...
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The present work seeks to assess the sustainability of different solar photovoltaic (SPV) electricity-generating systems based upon energy, environment and economics. The sustainability indicators evaluated for energy, environment and economics are electrical output, life-cycle greenhouse gas (GHG) emissions and life-cycle cost of electricity generated per kilowatt hour. The selected SPV-based electricity generation technologies for sustainability evaluation are amorphous, monocrystalline and polycrystalline at different locations and tilt angles across India. For SPV systems, most of the emissions are the result of electricity use during manufacturing. In these cases, an average grid mix for the region of manufacture is typically used to calculate energy use and emissions. Based upon these three indicators, a figure of merit (FM) has been proposed. The results proposed that polycrystalline gives the maximum electrical output, minimum GHG emission, minimum cost and maximum FM at a radiation level of 6 kWh/m~2/day with latitude and tilt angle of 34° and 35°, respectively. This work will be helpful to users of solar energy, academicians, researchers and other concerned persons, in understanding the importance, severity and benefits obtained by the application and implementation of the SPV electricity-generating systems.
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This paper presents a novel method for maximum utilisation of solar energy on solar collectors by
optimising tilt angle (β). The optimisation has been done in two steps, in first, the partial differential
equation of total radi...
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This paper presents a novel method for maximum utilisation of solar energy on solar collectors by
optimising tilt angle (β). The optimisation has been done in two steps, in first, the partial differential
equation of total radiation on tilted surface (H_T) is differentiated with respect to β and in second, Taylor’s
series expansion method is applied to find the optimised tilt angle (β_(Taylor)). The results so obtained
are applied to different locations of India and it is found that on anisotropic atmospheric conditions
the total monthly radiation falling on collector surface βTaylor is increased significantly at each location.
The maximum gain of 3.19% during winters, 2.46% during spring, no change during summers
and 3.14% during autumn is observed in Kolkata. Only 1.42% radiation losses on seasonal and 8.14%
radiation loss on annual basis as compared to radiation on monthly basis at New Delhi station are
observed.
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3D printing applications help solve challenges in the field of healthcare. These technologies evolved to produce custom-made medical devices and implants for patients and enhance medical education and research. This paper aims to ...
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3D printing applications help solve challenges in the field of healthcare. These technologies evolved to produce custom-made medical devices and implants for patients and enhance medical education and research. This paper aims to make readers aware of the role of 3D printing in the field of medical education. 3D printing technologies are part of additive manufacturing (AM) technologies. 3D printing shows excellent potential with unconventional materials like different types of plastic, ketones, wood, human cells, metal powder, ceramics, composites, smart material, etc. This manufacturing method is suitable for producing complex and intricate shaped medical objects of the required property with lesser wastage of material. This paper introduces 3D printing technology and the need to carry out this study related to medical education and research. A brief literature review of 3D printing has been carried out. The paper further discusses the capabilities of 3D printing in the field of medicine. Patient-specific 3D models are being designed and then manufactured and implanted. 3D models of defective body parts help surgical planning and better part designing. Finally, the paper discusses significant roles of 3D printing in healthcare education in a tabular form. For the future, this technology has immense potential for medical education, surgical planning and support including for a clear understanding of the disease.
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Castor oil plant (ricinus Communis) is growing in many places in the world, its seeds contain between 40% and 60% oil, the extract process are not toxic. The slow burning oil is used mostly to fuel lamps, lighting, body ointments,...
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Castor oil plant (ricinus Communis) is growing in many places in the world, its seeds contain between 40% and 60% oil, the extract process are not toxic. The slow burning oil is used mostly to fuel lamps, lighting, body ointments, and improving hair grown and texture, in local medicine as laxative, purgative and cathartic also for curing arthritic. Castor oil is the only oil in nature which having hydroxyl groups in backbone. It is chemically modified to obtain oil based polyols by mixing different fly ash percentages with them for preparation high rigid structural polyurethane (PU) with it. The generated polyols (castor oil + different fly ash percentages (10%, 15%, 20%, 25%, 30%) are being checked to get viscosities at different fly ash percentages.
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Nowadays, almost every firm focuses to beat the global competition across the worldwide. In order to deal with such situation, companies are undertaking efforts to improve the productivity of their products but at the minimum poss...
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Nowadays, almost every firm focuses to beat the global competition across the worldwide. In order to deal with such situation, companies are undertaking efforts to improve the productivity of their products but at the minimum possible cost. Asset management is one of the ways to enhance the productivity under cost constraint which may also be seen as the management strategy for different the phases of asset life cycle. Operations and maintenance is one of the important phases of asset life cycle that can be focussed to improve the productivity. This phase may extend the equipment life, improves availability and retains them in healthy positions. But at the same time, frequent maintenance actions may increase the maintenance cost thereby increase the life cycle cost of a product. The maintenance cost only includes the preventive and corrective maintenance cost and which may in-turn depend upon the scheduled maintenance interval. Thus, a trade-off between maintenance actions and operational objectives (i.e. availability, etc.) is required to minimize the maintenance cost. In this paper, the genetic algorithm is applied to optimize the maintenance cost for higher performance (i.e. availability). A case study is taken into consideration for implementing the GA to optimize the objective function. The three different cases are presented, in the first case, subassemblies are repaired during maintenance action(s); in the second case subassemblies are repaired in preventive maintenance action and while replaced in corrective maintenance action; in the last case, the subassemblies are replaced in both kind of maintenance. In order to check the robustness of the solution, the sensitivity analysis is also performs and that validates the strength of the solution methodology.
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