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1 – 10 of over 9000Fabian Kranert, Moritz Hinkelmann, Roland Lachmayer, Jörg Neumann and Dietmar Kracht
This study aims to extend the known design guidelines for the polymer-based fused filament fabrication (FFF) 3D printing process with the focus on function-integrated components…
Abstract
Purpose
This study aims to extend the known design guidelines for the polymer-based fused filament fabrication (FFF) 3D printing process with the focus on function-integrated components, specifically optomechanical parts. The potential of this approach is demonstrated by manufacturing function-integrated optomechanics for a low-power solid-state laser system.
Design/methodology/approach
For the production of function-integrated additively manufactured optomechanics using the FFF process, essential components and subsystems have been identified for which no design guidelines are available. This includes guidelines for integrating elements, particularly optics, into a polymer structure as well as guidelines for printing functional threads and ball joints. Based on these results, combined with prior research, a function-integrated low-power solid-state laser optomechanic was fabricated via the FFF process, using a commercial 3D printer of the type Ultimaker 3. The laser system's performance was assessed and compared to a reference system that employed commercial optomechanics, additionally confirming the design guidelines derived from the study.
Findings
Based on the design goal of function integration, the existing design guidelines for the FFF process are systematically extended. This success is demonstrated by the fabrication of an integrated optomechanic for a solid-state laser system.
Practical implications
Based on these results, scientists and engineers will be able to use the FFF process more extensively and benefit from the possibilities of function-integrated manufacturing.
Originality/value
Extensive research has been published on additive manufacturing of optomechanics. However, this research often emphasizes only cost reduction and short-term availability of components by reprinting existing parts. This paper aims to explore the capabilities of additive manufacturing in the production of function-integrated components to reduce the number of individual parts required, thereby decreasing the workload for system assembly and leading to an innovative production process for optical systems. Consequently, where needed, it provides new design guidelines or extends existing ones and verifies them by means of test series.
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Marina Bastos Carvalhais Barroso, Ricardo Silveira Martins and Jonathan Simões Freitas
This study aims to demonstrate a rigorous approach to applying the Repertory Grid Technique (RGT) and Honey’s Content Analysis (HCA) to obtain and process qualitative data through…
Abstract
Purpose
This study aims to demonstrate a rigorous approach to applying the Repertory Grid Technique (RGT) and Honey’s Content Analysis (HCA) to obtain and process qualitative data through structured interviews.
Design/methodology/approach
An illustrative case study using the OpenRepGrid package from the open-source software R facilitates a deeper understanding of these techniques. The study subjects were employees of a corporate charter company.
Findings
The RGT enables the identification of key attributes as perceived by interviewees regarding the phenomenon, whereas HCA clarifies how these attributes impact the desired analysis outcome. The presented case study identified constructs related to the client–supplier relationship and their impact on service performance from the provider’s perspective.
Research limitations/implications
This study illustrates the use of qualitative methods based on an interpretative naturalistic approach to rigorously and systematically capture interviewees’ perspectives.
Practical implications
The combination of RGT and HCA can be a valuable tool for management studies by allowing controlled researcher interference in empirical investigations. In addition, the data-driven selection of constructs by interviewees can lead to the emergence of novel theories.
Social implications
Using diverse methodologies enables researchers to address complex managerial challenges that often surpass the capabilities of conventional analysis methods.
Originality/value
The proposed methodology offers a robust understanding of phenomena from the interviewees’ perspectives. Consequently, this study highlights the potential of these techniques for theoretical and empirical research in the field of administration.
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Amit Rohilla, Neeta Tripathi and Varun Bhandari
In a first of its kind, this paper tries to explore the long-run relationship between investors' sentiment and selected industries' returns over the period January 2010 to…
Abstract
Purpose
In a first of its kind, this paper tries to explore the long-run relationship between investors' sentiment and selected industries' returns over the period January 2010 to December 2021.
Design/methodology/approach
The paper uses 23 market and macroeconomic proxies to measure investor sentiment. Principal component analysis has been used to create sentiment sub-indices that represent investor sentiment. The autoregressive distributed lag (ARDL) model and other sophisticated econometric techniques such as the unit root test, the cumulative sum (CUSUM) stability test, regression, etc. have been used to achieve the objectives of the study.
Findings
The authors find that there is a significant relationship between sentiment sub-indices and industries' returns over the period of study. Market and economic variables, market ratios, advance-decline ratio, high-low index, price-to-book value ratio and liquidity in the economy are some of the significant sub-indices explaining industries' returns.
Research limitations/implications
The study has relevant implications for retail investors, policy-makers and other decision-makers in the Indian stock market. Results are helpful for the investor in improving their decision-making and identifying those sentiment sub-indices and the variables therein that are relevant in explaining the return of a particular industry.
Originality/value
The study contributes to the existing literature by exploring the relationship between sentiment and industries' returns in the Indian stock market and by identifying relevant sentiment sub-indices. Also, the study supports the investors' irrationality, which arises due to a plethora of behavioral biases as enshrined in classical finance.
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Liwei Ju, Zhe Yin, Qingqing Zhou, Li Liu, Yushu Pan and Zhongfu Tan
This study aims to form a new concept of power-to-gas-based virtual power plant (GVPP) and propose a low-carbon economic scheduling optimization model for GVPP considering carbon…
Abstract
Purpose
This study aims to form a new concept of power-to-gas-based virtual power plant (GVPP) and propose a low-carbon economic scheduling optimization model for GVPP considering carbon emission trading.
Design/methodology/approach
In view of the strong uncertainty of wind power and photovoltaic power generation in GVPP, the information gap decision theory (IGDT) is used to measure the uncertainty tolerance threshold under different expected target deviations of the decision-makers. To verify the feasibility and effectiveness of the proposed model, nine-node energy hub was selected as the simulation system.
Findings
GVPP can coordinate and optimize the output of electricity-to-gas and gas turbines according to the difference in gas and electricity prices in the electricity market and the natural gas market at different times. The IGDT method can be used to describe the impact of wind and solar uncertainty in GVPP. Carbon emission rights trading can increase the operating space of power to gas (P2G) and reduce the operating cost of GVPP.
Research limitations/implications
This study considers the electrical conversion and spatio-temporal calming characteristics of P2G, integrates it with VPP into GVPP and uses the IGDT method to describe the impact of wind and solar uncertainty and then proposes a GVPP near-zero carbon random scheduling optimization model based on IGDT.
Originality/value
This study designed a novel structure of the GVPP integrating P2G, gas storage device into the VPP and proposed a basic near-zero carbon scheduling optimization model for GVPP under the optimization goal of minimizing operating costs. At last, this study constructed a stochastic scheduling optimization model for GVPP.
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Tran Thai Ha Nguyen, Gia Quyen Phan, Wing-Keung Wong and Massoud Moslehpour
This research examines the relationship between market power and liquidity creation in the specific context of bank profitability in the Vietnamese banking sector.
Abstract
Purpose
This research examines the relationship between market power and liquidity creation in the specific context of bank profitability in the Vietnamese banking sector.
Design/methodology/approach
The study applies the methodology proposed by Berger and Bouwman (2009) to demonstrate the creation of bank liquidity through a three-step procedure for investigating the relationship between market power and liquidity creation. The three steps include non-fat liquidity (NFLC), fat liquidity (FLC) and system generalized method of moments estimation for panel data.
Findings
This study finds that liquidity creation increases when a bank has high market power. Further, highly profitable banks positively impact the market power of banks with regard to liquidity creation, relative to less profitable banks. Moreover, bank size, capital, economic growth and interest rate negatively influence bank liquidity creation, while credit risk positively relates to bank liquidity creation.
Research limitations/implications
Measurements used in this study are based on the works of Berger and Bouwman (2009). There are specific variations, relative to Basel III. In addition, other variables significantly impact bank liquidity creation that have not been considered in the models, and a quadratic model should have been considered to measure market power and bank liquidity creation.
Practical implications
This study suggests that managers should control the liquidity of their banks by supervising vulnerable characteristics that have been mentioned herein and emphasizing improvements in profitability. Further, the government may consider encouraging banks to generate more liquidity by modifying regulations concerned with market power or reinforcing policies about improving the transparent business environment.
Originality/value
This study characterizes an attempt to examine the influence of market power on the liquidity creation of banks in Vietnam, which represents one of the most dynamic systems in Asia, with several varied participating banks. The current study also examines the same within the specific context of the modifying impact of the profitability of banks.
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Daring to challenge the status quo impacts innovation. Yet, successful outcomes depend on individual risk-taking and choice to influence others to support new ideas. This…
Abstract
Daring to challenge the status quo impacts innovation. Yet, successful outcomes depend on individual risk-taking and choice to influence others to support new ideas. This Challenging the Status Quo exercise illustrates how leaders use power and influencing tactics to challenge norms by analyzing Donald Trump’s journey as the 45th U.S. President to defy experts and successfully influence followers to support his non-traditional candidacy: businessman lacking political experience becoming leader of the free world. Through integrating videoclips and polls, instructors make power visible, relevant, and thought-provoking as students apply power theory and influencing tactics perspectives to analyze (a) how leaders impact followers’ perceptions, (b) students mutual-influencing strategies, (c) power’s relationship with social identity and privilege, and (d) social impact on innovation via activism and free speech.
RS. Koteeshwari and B. Malarkodi
Among the proposed radio access strategies for improving system execution in 5G networks, the non-orthogonal multiple access (NOMA) scheme is the prominent one.
Abstract
Purpose
Among the proposed radio access strategies for improving system execution in 5G networks, the non-orthogonal multiple access (NOMA) scheme is the prominent one.
Design/methodology/approach
Among the most fundamental NOMA methods, power-domain NOMA is the one where at the transmitter, superposition coding is used, and at the receiver, successive interference cancellation (SIC) is used. The importance of power allocation (PA) in achieving appreciable SIC and high system throughput cannot be overstated.
Findings
This research focuses on an outage probability analysis of NOMA downlink system under various channel conditions like Rayleigh, Rician and Nakagami-m fading channel. The system design's objectives, techniques and constraints for NOMA-based 5G networks' PA strategies are comprehensively studied.
Practical implications
From the results of this study, it is found that the outage probability performance of downlink ordered NOMA under Rayleigh, Rician and Nakagami-m fading channel was good.
Originality/value
Outage probability analysis of downlink ordered NOMA under various channel conditions like Rayleigh, Rician and Nakagami-m fading channels were employed. Though the performance of Nakagami-m fading channel is lesser compared to Rayleigh channel, the performance for user 1 and user 2 are good.
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Manuele Bertoluzzo, Paolo Di Barba, Michele Forzan, Maria Evelina Mognaschi and Elisabetta Sieni
The purpose of the study is to design the compensation network of a dynamic wireless power transfer system, considering the movement of the receiving coil along an electrified…
Abstract
Purpose
The purpose of the study is to design the compensation network of a dynamic wireless power transfer system, considering the movement of the receiving coil along an electrified track with a large number of inductors buried on the road.
Design/methodology/approach
A finite element model has been developed to calculate the self-inductances of transmitting and receiving coils as well as the mutual inductances between the receiving coil and the transmitting ones in the nearby and for various relative positions. The calculated lumped parameters, self-inductances and mutual inductances depending on the relative positions between the coils, have been considered to design the compensation network of the active coils, which is composed of three capacitive or inductive reactances connected in the T form. The optimal values of the six reactances, three for the transmitting coils and three for the receiving one, have been calculated by resorting to the Genetic Algorithm NSGA-II.
Findings
In this paper, the results obtained by means of the optimizations have broadly discussed. The optimal values of the reactances of the compensation networks show a clear trend in the receiving part of the circuit. On the other hand, the problem seems very sensitive to the values of the reactances in the transmitting circuit.
Originality/value
Dynamic wireless power transfer system is one of the newest ways of recharging electric vehicles. Hence, the design of compensation networks for this kind of systems is a new topic, and there is the need to investigate possible solutions to obtain a good performance of the recharging system.
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Hoyon Hwang, Jaeyoung Cha and Jon Ahn
The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft…
Abstract
Purpose
The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft design framework provides a simple method to design solar aircraft for users of all levels of experience.
Design/methodology/approach
This design framework consists of algorithms and user interfaces for the design of experiments, optimization and mission analysis that includes aerodynamics, performance, solar energy, weight and flight distances.
Findings
The proposed sizing method produces the optimal solar aircraft that yields the minimum weight and satisfies the constraints such as the power balance, the night time energy balance and the lift coefficient limit.
Research limitations/implications
The design conditions for the sizing process are given in terms of mission altitudes, flight dates, flight latitudes/longitudes and design factors for the aircraft configuration.
Practical implications
The framework environment is light and easily accessible as it is implemented using open programs without the use of any expensive commercial tools or in-house programs. In addition, this study presents a sizing method for solar aircraft as traditional sizing methods fail to reflect their unique features.
Social implications
Solar aircraft can be used in place of a satellite and introduce many advantages. The solar aircraft is much cheaper than the conventional satellite, which costs approximately $200-300m. It operates at a closer altitude to the ground and allows for a better visual inspection. It also provides greater flexibility of missions and covers a wider range of applications.
Originality/value
This study presents the implementation of a function that yields optimized flight performance under the given mission conditions, such as climb, cruise and descent for a solar aircraft.
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Poh Yen Ng, Bronwyn P. Wood and Bettina Lynda Bastian
The purpose of this study is to develop an empirically informed framework to analyze women empowerment and entrepreneurship, contextualized within a collective society.
Abstract
Purpose
The purpose of this study is to develop an empirically informed framework to analyze women empowerment and entrepreneurship, contextualized within a collective society.
Design/methodology/approach
The authors conducted 15 in-depth semi-structured interviews with women entrepreneurs located in the United Arab Emirates to understand their entrepreneurial experiences and how they were empowered.
Findings
Findings suggest that the three aspects of power characterized as “positive” from within Rowlands’ distinctions (“power to”, “power with” and “power within”) dominate, as opposed to those emphasized in the literature (“power to” and “power over”). Findings include empowerment of the “me” (individual) also synergistically contributes to empowerment of the “we” (society), when considering empowerment within a collective society.
Originality/value
A psychology model was used as a basis to develop a Collective Empowerment Process Framework. This framework provides a fresh look at empowerment, allowing for explanations of how women in specific contexts experience empowerment and social change.
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