Venkata Suresh Bade, Srinivasa Rao P. and Govinda Rao P.
The purpose of this paper is to investigate the prominence of mechanical excitations at the time of welding. In the past years, the process of welding technology has expanded its…
Abstract
Purpose
The purpose of this paper is to investigate the prominence of mechanical excitations at the time of welding. In the past years, the process of welding technology has expanded its influence in manufacturing. The crucial drawback of conventional welding is prompted by internal stresses and distortions, which is the focal reason for weld defects. These weld defects can be diminished by the process called post-weld heat treatment (PWHT), which consumes more working hours and needs skilled workers. To replace these PWHT processes, mechanical vibrations are introduced during the process of welding to diminish these weld defects.
Design/methodology/approach
In the current research, the mechanical vibrations are transferred to weld-pool through vibro-motor and DC motor connected to the electrode. As per standards, the tensile test specimens were prepared for welding with different voltages of vibro-motor and DC motor respectively. The weld joints were tested for tensile strength and analyzed the microstructure at the fusion zone.
Findings
Melt-ability at fusion zone of 1018 mild steel was investigated by the single-stroke intense heat process of fusion welding. It is observed that the mechanical vibrations technique has a profound influence on the enhancement of the fusion zone characteristics and grain structure. The peak value of the tensile strength is observed at 100 s of vibration, 190 V of vibro-motor voltage and 18 V of electrode voltage. The tensile strength of the welded joints with vibrations is increased up to 22.64% when it is compared with conventional welding. The enhancement of the tensile strength of the weld bead was obtained because of the formation of fine grain structure. So, mechanical vibrations are identified as the most convenient method for improving the mild steel alloys weld quality.
Originality/value
A novel approach called mechanical vibrations during the process of welding is implemented for fusion zone refinement.
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M. Vykunta Rao, Srinivasa Rao P. and B. Surendra Babu
Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand the…
Abstract
Purpose
Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand the influence of vibratory weld conditioning on the mechanical and microstructural characterization of aluminum 5052 alloy weldments. An attempt is made to understand the effect of the vibratory tungsten inert gas (TIG) welding process parameters on the hardness, ultimate tensile strength and microstructure of Al 5052-H32 alloy weldments.
Design/methodology/approach
Aluminum 5052 H32 specimens are welded at different combinations of vibromotor voltage inputs and time of vibrations. Voltage input is varied from 50 to 230 V at an interval of 10 V. At each voltage input to the vibromotor, there are three levels of time of vibration, i.e. 80, 90 and 100 s. The vibratory TIG-welded specimens are tested for their mechanical and microstructural properties.
Findings
The results indicate that the mechanical properties of aluminum alloy weld connections improved by increasing voltage input up to 160 V. Also, it has been observed that by increasing vibromotor voltage input beyond 160 V, mechanical properties were reduced significantly. It is also found that vibration time has less influence on the mechanical properties of weld connections. Improvement in hardness and ultimate tensile strength of vibratory welded joints is 16 and 14%, respectively, when compared without vibration, i.e. normal weld conditions. Average grain size is measured as per ASTM E 112–96. Average grain size is in the case of 0, 120, 160 and 230 is 20.709, 17.99, 16.57 and 20.8086 µm, respectively.
Originality/value
Novel vibratory TIG welded joints are prepared. Mechanical and micro-structural properties are tested.
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Manikandan Subramaniyan, Sasitharan Subramaniyan, Moorthy Veeraswamy and Viswanatha Rao Jawalkar
This paper aims to address not only technical and economic challenges in electrical distribution system but also environmental impact and the depletion of conventional energy…
Abstract
Purpose
This paper aims to address not only technical and economic challenges in electrical distribution system but also environmental impact and the depletion of conventional energy resources due to rapidly growing economic development, results rising energy consumption.
Design/methodology/approach
Generally, the network reconfiguration (NR) problem is designed for minimizing power loss. Particularly, it is devised for maximizing power loss reduction by simultaneous NR and distributed generation (DG) placement. A loss sensitivity factor procedure is incorporated in the problem formulation that has identified sensitivity nodes for DG optimally. An adaptive weighted improved discrete particle swarm optimization (AWIDPSO) is proposed for ascertaining a feasible solution.
Findings
In AWIDPSO, the adaptively varying inertia weight increases the possible solution in the global search space and it has obtained the optimum solution within lesser iteration. Moreover, it has provided a solution for integrating more amount of DG optimally in the existing distribution network (DN).
Practical implications
The AWIDPSO seems to be a promising optimization tool for optimal DG placement in the existing DN, DG placement after NR and simultaneous NR and DG sizing and placement. Thus, a strategic balance is derived among economic development, energy consumption, environmental impact and depletion of conventional energy resources.
Originality/value
In this study, a standard 33-bus distribution system has been analyzed for optimal NR in the presence of DG using the developed framework. The power loss in the DN has reduced considerably by indulging a new and innovative approaches and technologies.
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Alekhya Sabbithi, S.G.D.N. Lakshmi Reddi, R. Naveen Kumar, Varanasi Bhaskar, G.M. Subba Rao and Sudershan Rao V.
The purpose of this paper is to identify and prioritize the key food safety practices among street food handlers that lead to microbial contamination in selected street foods of…
Abstract
Purpose
The purpose of this paper is to identify and prioritize the key food safety practices among street food handlers that lead to microbial contamination in selected street foods of Hyderabad, India. These key food safety practices will help develop and design tailor-made training material for street food vendors in future.
Design/methodology/approach
It is a cross-sectional study conducted in south Indian city of Hyderabad. Stratified random sampling method was employed. A total of 463 samples of street foods were collected from five zones of Hyderabad. They included 163 salad toppings, 150 fresh fruit juices and 150 panipuri samples. Identification and enumeration of foodborne pathogens and indicator organisms (S. aureus, E. coli, Salmonella spp., Shigella spp., Bacillus cereus, Yersinia spp.) were performed as described by USFDA-BAM. Information on food safety knowledge and handling practices from street vendors were collected using a structured questionnaire. Associations between hygiene practices and bacterial pathogens were done using ANOVA. Risk estimation of food safety practices was assessed by calculating odds ratio.
Findings
Microbiological analysis indicated that a large number of carrot (98.1 percent) and onion (75.5 percent) samples were contaminated with E. coli. Peeled and cut fruits left uncovered have 13.4 times risk (OR: 2.40-74.8) of E. coli contamination compared to the covered ones. Panipuri samples picked from the vendors who did not have soap at the vending unit had significantly (p<0.001) higher contamination of fecal coliforms than those who had.
Originality/value
This study is the first of its kind in the study area.
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Venkata Suresh Bade, Srinivasa Rao P. and Govinda Rao P.
The purpose of this study is to explore the importance of vibrations during welding process. In recent years, welding has gained its supremacy in the field of production. The main…
Abstract
Purpose
The purpose of this study is to explore the importance of vibrations during welding process. In recent years, welding has gained its supremacy in the field of production. The main set back of the welding process is induced residual stresses, which is a major cause for many welding defects. These defects can be minimized by post-weld heat treatment methods, which is a time consuming and laborious process. In the recent past, a technique of exciting the weld-pool by vibrating the work-pieces was also adopted to minimize the above-mentioned stresses. A novel technique of electrode vibration is another effective way of transferring the vibrations to the weld-pool to influence the induced residual stress.
Design/methodology/approach
In this research, the electrode is vibrated with the help of an electric motor. The specimens were prepared as per American Society for Testing and Materials standards and welded with varying frequencies and voltages. The weldments are tested for hardness along the weld bead and heat affected zone, also the microstructure of the fusion zone is analyzed.
Findings
It is observed that there is an improvement in the hardness because of the grain refinement, which is a result of proper excitation of the weld-pool. It is observed that there is an improvement in hardness test up to 28.69% when compared with the conventional welding process. The peak value of hardness is observed at a frequency of 4,450 Hz. This is because of fine grain structure at this frequency, which is observed through the microstructure analysis.
Originality/value
A novel technique is introduced to refine the weld-pool through electrode vibrations. To improve the hardness of the welded joints, vibrations play a major role by refining the grain structure. The vibrations are imparted with the help of a special equipment attached to the electrode.
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In about 1990, India and a few developing countries attempted to restructure their economics to achieve accelerated economic growth, for generation of optimum levels of…
Abstract
In about 1990, India and a few developing countries attempted to restructure their economics to achieve accelerated economic growth, for generation of optimum levels of production, employment and poverty alleviation. The economic and fiscal policies took a turn towards liberalisation, deregulation, de‐control and de‐licensing, so that the economy opens up and unnecessary legal and bureaucratic impediments are removed to reduce delays and costs. During the last five years, industrial, trade and tax reforms have created demonstrable buoyancy in industrial production, investment and exports.
Manjunath Beemappa Edigar and P.V. Rao
In the past recent years, wireless sensor network (WSN) has progressively grown as an emerging technology. Various research efforts have been made in the literature to address the…
Abstract
Purpose
In the past recent years, wireless sensor network (WSN) has progressively grown as an emerging technology. Various research efforts have been made in the literature to address the problem associated with WSN security. Based on the review analysis, it is found that the existing methods are mostly associated with complex security operations that are not suitable for resource constraint sensor nodes. The proposed paper has presented cost-effective modeling of the security framework that addresses the problem of security and energy in WSN.
Design/methodology/approach
The proposed security framework implements two different protocols to attain maximum security services and optimizes the security operation of the proposed security models to achieve higher energy efficiency and privacy preservation against a majority of the lethal attacks. The first security model introduces a novel cost-efficient pairwise key-based authentication mechanism to identify the availability of optimal routes under the presence of adversary in the network. The second security model introduces an integrated part of the first security model that optimizes security operation to perform secure communication using a lightweight encryption mechanism.
Findings
Based on the experimental outcome and analysis, the proposed system attains a 60% performance improvement in terms of security and computational efficiency compared to the existing Sec-LEACH. The second security model has achieved a 50% improvement in terms of overall aspects like reduction in transmission delay, packet delivery ratio, remaining energy and communication performance.
Originality/value
The proposed study has presented a computationally efficient model that provides lightweight security operations based on secure hash function. It also focuses on the security associations between WSN nodes and the selection of reliable routes for secure data transmission. The design of the proposed security model is best suited for homogeneous and heterogeneous sensor networks, which will be robust to any attacking scenario.
Details
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Naganagouda Patil, Preethi N. Patil and P.V. Rao
The abnormalities of glaucoma have high impact on deciding and representing the causes that effects severity of blindness in human beings. The simulation experimental results…
Abstract
Purpose
The abnormalities of glaucoma have high impact on deciding and representing the causes that effects severity of blindness in human beings. The simulation experimental results would help the ophthalmologist in diagnosing of glaucoma abnormality accurately. The significant effect of glaucoma has a huge impact on the quality of human life, and its growth rate in world population tremendously increases. Glaucoma is considered as second largest cause for the blindness in the world; hence identification of it marks the importance of its detection at the earliest.
Design/methodology/approach
The prime objective of the work proposed is to build up a human intervention free image preparing framework for glaucoma screening. The disc calculation is assessed on retinal image dataset called retinal Image for glaucoma Analysis. The proposed method briefs a novel optic disc division calculation depending on applying a level-set strategy on a confined optic disc image. In the instance of low quality image, a twofold level set is designed, in which the principal level set is viewed as restriction for the optic disc. To keep the veins from meddling with the level-set procedure, an inpainting strategy has been applied. Also a significant commitment is to include the varieties in notion adopted by the ophthalmologists in distinguishing the disc localization and diagnosing the glaucoma. Most of the past investigations are prepared and tested depending on just a single feature, which can be thought to be one-sided for the ophthalmologist.
Findings
In continuation, the correctness has been determined depending on the quantity of image that matched with the investigation pattern adopted by the ophthalmologist. The 175 retinal images were utilized to test the results of proposed work with the manual markings of ophthalmologists. The error-free calculation in marking the optic disc region and centroid was 98.95% in comparison with the existing result of 87.34%.
Originality/value
In continuation, the correctness has been determined depending on the quantity of image that matched with the investigation pattern adopted by the ophthalmologist. The 175 retinal images were utilized to test the results of proposed work with the manual markings of ophthalmologists. The error-free calculation in marking the optic disc region and centroid was 98.95% in comparison with the existing result of 87.34%.
Details
Keywords
Marc Wouters, Susana Morales, Sven Grollmuss and Michael Scheer
The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and…
Abstract
Purpose
The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and it provides a comparison to an earlier review of the management accounting (MA) literature (Wouters & Morales, 2014).
Methodology/approach
This structured literature search covers papers published in 23 journals in IOM in the period 1990–2014.
Findings
The search yielded a sample of 208 unique papers with 275 results (one paper could refer to multiple cost management methods). The top 3 methods are modular design, component commonality, and product platforms, with 115 results (42%) together. In the MA literature, these three methods accounted for 29%, but target costing was the most researched cost management method by far (26%). Simulation is the most frequently used research method in the IOM literature, whereas this was averagely used in the MA literature; qualitative studies were the most frequently used research method in the MA literature, whereas this was averagely used in the IOM literature. We found a lot of papers presenting practical approaches or decision models as a further development of a particular cost management method, which is a clear difference from the MA literature.
Research limitations/implications
This review focused on the same cost management methods, and future research could also consider other cost management methods which are likely to be more important in the IOM literature compared to the MA literature. Future research could also investigate innovative cost management practices in more detail through longitudinal case studies.
Originality/value
This review of research on methods for cost management published outside the MA literature provides an overview for MA researchers. It highlights key differences between both literatures in their research of the same cost management methods.