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This paper aims to focus on reducing lead-time and energy consumption for laser-based metal deposition of Inconel-625 superalloy and to investigate the effect of process parameters on microstructure, density, surface roughness, dimensional accuracy and microhardness.

Inconel material was deposited on steel substrate by varying process parameters such as laser power, laser scan speed and powder flow rate. The deposited parts were characterized for their density, surface roughness, dimensional accuracy and microhardness.

The study reveals that with increase in laser power, laser scan speed and powder flow rate, there was an increase in density, surface roughness values and microhardness of the deposits, while there was a decrease in dimensional accuracy, deposition time and energy consumption.

The results of this study can be useful in fabrication of Inconel components by laser-based metal deposition process, and the methodology can be expanded to other materials to reduce the lead-time and energy consumption effectively.

The present study gives an understanding of effect of process parameters on density, surface roughness, dimensional accuracy, microhardness, deposition time and energy consumption for laser-based metal deposition of Inconel-625.

Filter design plays an essential role in most communication standards. The essential element of the software-defined radio is a channelizer that comprises several channel filters. Designing filters with lower complexity, minimized area and enhanced speed is a demanding task in currently prevailing communication standards. This study aims to propose an efficient reconfigurable residue number system (RNS)-based multiply-accumulate (MAC) channel filter for software radio receivers.

RNS-based pipelined MAC module for the realization of channel finite impulse response (FIR) filter architecture is considered in this work. Further, the use of a single adder and single multiplier for realizing the filter architecture regardless of the number of taps offers effective resource sharing. This design provides significant improvement in speed of operation as well as a reduction in area complexity.

In this paper, two major tasks have been considered: first, the RNS number conversion is performed in which the integer is converted into several residues. These residues are processed in parallel and are applied to the MAC-FIR filter architecture. Second, the MAC filter architecture involves pipelining, which enhances the speed of operation to a significant extent. Also, the time-sharing-based design incorporates a single partial product-based shift and add multiplier and single adder, which provide a low complex design. The results show that the proposed 16-tap RNS-based pipelined MAC sub-filter achieves significant improvement in speed as well as 89.87% area optimization when examined with the conventional RNS-based FIR filter structure.

The proposed MAC-FIR filter architecture provides good performance in terms of complexity and speed of operation because of the use of the RNS scheme with pipelining and partial product-based shift and adds multiplier and single adder when examining with the conventional designs. The reported architecture can be used in software radios.

In this paper, the authors present different methods for reconfigurable finite impulse response (RFIR) filter design. Distributed arithmetic (DA)-based reconfigurable FIR filter design is suitable for software-defined radio (SDR) applications. The main contribution of reconfiguration is reuse of registers, multipliers, adders and to optimize various parameters such as area, power dissipation, speed, throughput, latency and hardware utilizations of flip-flops and slices. Therefore, effective design of building blocks will be optimized for RFIR filter with all the above parameters.

The modified, direct form register structure of FIR filter contributes the reuse concept and allows utilization of less number of registers and parallel computation operations. The disadvantage of DA and other conventional methods is delay increases proportionally with filter length. This is due to different partial products generated by adders. The usage of adder and multipliers in DA-FIR filter restricts the area and power dissipation because of their complexity of generation of sum and carry bits. The hardware implementation time of an adder can be reduced by parallel prefix adder (PPA) usage based on Ling equation. PPA uses shift-add multiplication, which is a repetitive process of addition, and this process is known as Bypass Zero feed multiplicand in direct multiplication, and the proposed technique optimizes area-power product efficiently. The modified DA (MDA)-based RFIR filter is designed for 64 taps filter length (N). The design is developed by using Verilog hardware description language and implemented on field-programmable gate array. Also, this design validates SDR channel equalizer.

Both RFIR and SDR are integrated as single system and implemented on Artix-7 development board of XC7A100tCSG324 and exploited the advantages in area-delay, power-speed products and energy efficiency. The theoretical and practical comparisons have been carried out, and the results are compared with existing DA-RFIR designs in terms of throughput, latency, area-delay, power-speed products and energy efficiency, which are improved by 14.5%, 23%, 6.5%, 34.2% and 21%, respectively.

The DA-based RFIR filter is validated using Chipscope Pro software tool on Artix-7 FPGA in Xilinx ISE design suite and compared constraint parameters with existing state-of-art results. It is also tested the filtering operation by applying the RFIR filter on Audio signals for removal of noisy signals and it is found that 95% of noise signals are filtered effectively.

Digital signal processing (DSP) applications such as finite impulse response (FIR) filter, infinite impulse response and wavelet transformation functions are mainly constructed using multipliers and adders. The performance of any digital applications is dependent on larger size multipliers, area and power dissipation. To optimize power and area, an efficient zero product and feeder register-based multiplier (ZP and FRBM) is proposed. Another challenging task in multipliers is summation of partial products (PP), results in more delay. To address this issue, the modified parallel prefix adder (PPA) is incorporated in multiplier design. In this work, different methods are studied and analyzed for designing FIR filter, optimized with respect to area, power dissipation, speed, throughput, latency and hardware utilization.

The distributed arithmetic (DA)-based reconfigurable FIR design is found to be suitable filter for software-defined radio (SDR) applications. The performance of adder and multipliers in DA-FIR filter restricts the area and power dissipation due to their complexity in terms of generation of sum and carry bits. The hardware implementation time of an adder can be reduced by using PPA which is based on Ling equation. The MDA-RFIR filter is designed for higher filter length (N), i.e. N = 64 with 64 taps and this design is developed using Verilog hardware description language (HDL) and implemented on field-programmable gate array. The design is validated for SDR channel equalizer; both RFIR and SDR are integrated as single system and implemented on Artix-7 development board of part name XC7A100tCSG324.

The MDA-RFIR for N = 64 is optimized about 33% in terms of area-delay, power-speed product and energy efficiency. The theoretical and practical comparisons have been done, and the practically obtained results are compared with existing DA-RFIR designs in terms of throughput, latency, area-delay, power-speed product and energy efficiency are better about 3.5 times, 31, 45 and 29%, respectively.

The MDA-RFIR for N = 64 is optimized about 33% in terms of area-delay, power-speed product and energy efficiency.

This study aims to discuss the state-of-the-art digital factory (DF) development combining digital twins (DTs), sensing devices, laser additive manufacturing (LAM) and subtractive manufacturing (SM) processes. The current shortcomings and outlook of the DF also have been highlighted. A DF is a state-of-the-art manufacturing facility that uses innovative technologies, including automation, artificial intelligence (AI), the Internet of Things, additive manufacturing (AM), SM, hybrid manufacturing (HM), sensors for real-time feedback and control, and a DT, to streamline and improve manufacturing operations.

This study presents a novel perspective on DF development using laser-based AM, SM, sensors and DTs. Recent developments in laser-based AM, SM, sensors and DTs have been compiled. This study has been developed using systematic reviews and meta-analyses (PRISMA) guidelines, discussing literature on the DTs for laser-based AM, particularly laser powder bed fusion and direct energy deposition, in-situ monitoring and control equipment, SM and HM. The principal goal of this study is to highlight the aspects of DF and its development using existing techniques.

A comprehensive literature review finds a substantial lack of complete techniques that incorporate cyber-physical systems, advanced data analytics, AI, standardized interoperability, human–machine cooperation and scalable adaptability. The suggested DF effectively fills this void by integrating cyber-physical system components, including DT, AM, SM and sensors into the manufacturing process. Using sophisticated data analytics and AI algorithms, the DF facilitates real-time data analysis, predictive maintenance, quality control and optimal resource allocation. In addition, the suggested DF ensures interoperability between diverse devices and systems by emphasizing standardized communication protocols and interfaces. The modular and adaptable architecture of the DF enables scalability and adaptation, allowing for rapid reaction to market conditions.

Based on the need of DF, this review presents a comprehensive approach to DF development using DTs, sensing devices, LAM and SM processes and provides current progress in this domain.

The purpose of the study is to examine the relationship between the application of smart electronic systems, firm characteristics and efficient energy consumption: a case of public universities in Uganda.

The study adopted both quantitative and qualitative approach as well as descriptive cross-sectional survey design tantamounting to an experimental-observation approach. A sample of four public academic universities were explored using primary data. A semi-structured questionnaire together with an evaluation form and a tested experimental kit (from one of the leading electronics centres in Uganda) was used to examine the consumption rates of different electronic appliances of less than 30 Amps. Further, a Pearson product moment correlation (r) analysis was also used to determine the direction of a relationship among the variables together with a linear relationship (regression) to predict a linear association of one or more variables. Recommendations were also given.

Smart electronic systems make a significant determining factor to both firm characteristics (age, number of students, administrative staff and support staff) as well as efficient energy consumption. Nonetheless, there is no significant difference of efficient energy consumption as far as firm characteristics are concerned.

Results support the contributions of the theory of technology and acceptance model by affirming that a number of factors influence the usefulness and ease of use of the smart electronic systems, which in turn influence energy consumption.

Universities' management should endeavour to install smart electronic systems. But still, government should try to lower taxes on smart electronic systems and genuine agents should be named for easy and affordable access of the users, universities inclusive.

The study contributes towards a theoretical position by affirming the usefulness of technology acceptance model for efficient energy consumption in public universities.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-02-2019-0083

The purpose of this paper is to overview the literature about the environmental performance of additive manufacturing (AM) and to evaluate the use of life cycle assessment (LCA) on these studies.

This study was based on the systematic literature review.

The investigation found that most authors were concerned about the energy consumption of the AM equipment, which is the subject studied by 87% of articles. In addition, 25% of the studies used LCA at least in some level, making a global environment assessment to evaluate the environmental impacts of AM. By analyzing research studies, it was possible to find signs that AM could be a lower environmental impact process, when compared with traditional manufacturing. However, this assumption is not valid in all cases because there are many variables that may affect environmental results.

Due to the increase on the usage of this type of technology by industries, studies on the environmental performance of this process became relevant.

Aerospace and defence industries use the materials having better properties at elevated temperatures, and Inconel 718 is one of that. The complexity in realizing complex and intricate shapes necessitate the product realization through additive manufacturing. This paper aims to investigate the wear behaviour of additive manufactured material.

The wear behaviour of additively manufactured Inconel 718 samples through direct metal laser sintering process at three different build orientations was experimentally investigated using a standard pin-on-disc wear tester.

Among the varied wear parameters, the load was identified as the most influencing parameter on the wear rate. In addition, the post-failure analysis of the worn surface of the pins under the scanning electron microscopy revealed the presence of various wear mechanisms.

Almost, the industries are now focussed on their production through additive manufacturing owing to its advantages. The present work displays the wear behaviour of the additive manufactured Inconel 718 and its associated wear mechanisms.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0322.

This study aims to highlight potential savings in advertising budgets.

This study uses modern computer-based tools including stochastic dominance to check if advertising expenses are increasing sales by using modern causality assessment tools which allow for nonlinearities and use sophisticated assessment of causal impact of ads on sales.

This study identifies specific media spots where ad budget savings are possible. The marketing managers can take the next step to make small-scale local experiments to reassess this study’s findings.

This study is a statistical observational assessment not based on controlled experiments.

The authors have tools to identify ineffective advertising which can produce huge savings for the organization. The over-the-counter cold remedies have become important due to the pandemic. The tools have wider applicability in marketing research.

Less wasteful expenses always benefit the society.

To the best of the authors’ knowledge, this may be the first such attempt to use sophisticated causal identification tools. Remedies for the common cold sold by seven major US retailers help identify specific retailers and specific media with negative returns on investment.

Change in culture brought about by effective leadership is at the core of this case. Therefore, two broad topics can be discussed using this case: organizational culture change and Change Leadership OR Role of leaders in organzational change.

The case was prepared using primary data collected through a series of interviews conducted with participants of the change process. The participants included R. Sivanesan, Senior Vice President (Quality, Sourcing and Supply Chain) of Ashok Leyland, many members of the quality team, production department, HR executives and members of the marketing team. Secondary data in the form of an interview of Mr Vinod Dasari published in a popular magazine Autocar Professionals and organizational documents/presentations used during the change process were also used to build the case.

In 2011, when Vinod Dasari took over as the Managing Director and CEO of Ashok Leyland (AL), he hired R. Sivanesan. The quality standards of the vehicles produced in the AL plants in 2011 was far from satisfactory. He decided to change this. Part A of the case discusses the challenges faced by Sivanesan and Vinod Dasari in bringing about a change in the quality management practices at AL. Part B discusses the steps they actually took and the change that resulted from it.

At the end of the case discussion, the participants will be able to develop an understanding of the various aspects of organizational culture and how it manifests itself; become aware of the underlying causes of resistance to change; critically evaluate and apply various theories of change management; create an action plan for changing the culture of any organization; and appreciate the role of leaders as change agents.

The central theme in this case is managing culture change within organizations through effective leadership. Instructors teaching courses in organizational theory, organization structure/culture and leadership will find this case relevant. It is primarily intended for use in MBA and Executive Education programs in Management.