Than Lin, Jae‐Woo Lee and Tun Lwin
The purpose of this research is to develop an integrated model for composite rotor blade manufacturing cost estimates at the conceptual design stage. The integrated model seeks to…
Abstract
Purpose
The purpose of this research is to develop an integrated model for composite rotor blade manufacturing cost estimates at the conceptual design stage. The integrated model seeks to provide a rapid and dynamic feedback based on evaluating the manufacturing cost estimate for a new product design at the conceptual design stage. This paper describes the automated estimating process for design to manufacturing cost of composite rotor blade.
Design/methodology/approach
An integrated approach is implemented for evaluating the manufacturing cost estimates. The paper develops each module of the computer‐aided parametric model generation, time estimation models for composite manufacturing processes and decision support system. Finally, process flow data integration is done for all the modules. An example for a complicated geometric rotor blade is shown in this research paper. The results are compared in different design parameters and discussed.
Findings
The data integration for this approach was built by using ModelCenter® software. It is easier and more robust to apply than the other proposed methods. The selection of design, material and manufacturing parameters is achieved by integrated model within a short period of time.
Practical implications
This paper provides an integrated concurrent approach for manufacturing cost evaluation of composite rotor blade. Manufacturing factors could be considered at the early stage of product development phase.
Originality/value
This paper suggests an effective and efficient way of evaluating the manufacturing cost at the conceptual stage of the design process. The concurrent engineering and integrated product process development approaches were addressed.
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Ngoc Anh Vu, Than Lin, Abdulaziz Azamatov, Tun Lwin and Jae‐Woo Lee
The purpose of this paper is to develop an integrated rotorcraft design and virtual manufacturing framework. The framework consists of two major sub‐frameworks which are e‐design…
Abstract
Purpose
The purpose of this paper is to develop an integrated rotorcraft design and virtual manufacturing framework. The framework consists of two major sub‐frameworks which are e‐design and virtual manufacturing frameworks. This paper aims to describe the process of generating a specific framework for helicopter design and manufacturing in general, and a method for main rotor blade design.
Design/methodology/approach
The e‐design process integrates a pre‐conceptual, conceptual and preliminary design phases and includes many high accuracy physics‐based analysis tools and in‐house codes. The development of analysis programs and integration of flow data are discussed under the e‐design process. The virtual manufacturing process discusses physical three‐dimensional (3D) prototypes using rapid prototyping, virtual process simulation model development using Delmia Quest, virtual machine tool simulation and process‐based cost model. Vehicle geometry is modelled parametrically in computer‐aided 3D interactive application (CATIA) V5 to enable integration between the e‐design and virtual manufacturing processes, and then saved in Enovia SmartTeam which is commercial software for product data management (PDM). Data saved in Enovia SmartTeam are used as a database for the virtual manufacturing process.
Findings
The integration framework was constructed by using Model Center software. A multi‐disciplinary design optimization loop for rotor blade considering manufacturing factors is discussed to demonstrate the robustness and efficiency of the framework.
Practical implications
The manufacturing (practical factors) could be considered at an early stage of the rotor blades design.
Originality/value
The gap between theoretical (engineering design: aerodynamic, structural, dynamic, design, etc.) and practical aspects (manufacturing) is bridged through integrated product/process development framework. The modern concurrent engineering approach is addressed for helicopter rotor blade design throughout the case study.
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He held talks with his junta-appointed counterpart, Wunna Maung Lwin, on the sidelines of the seventh foreign ministers’ meeting of the Lancang-Mekong Cooperation (LMC) mechanism…
Details
DOI: 10.1108/OXAN-DB271378
ISSN: 2633-304X
Keywords
Geographic
Topical
N. Aswini, E. Krishna Kumar and S.V. Uma
The purpose of this paper is to provide an overview of unmanned aerial vehicle (UAV) developments, types, the major functional components of UAV, challenges, and trends of UAVs…
Abstract
Purpose
The purpose of this paper is to provide an overview of unmanned aerial vehicle (UAV) developments, types, the major functional components of UAV, challenges, and trends of UAVs, and among the various challenges, the authors are concentrating more on obstacle sensing methods. This also highlights the scope of on-board vision-based obstacle sensing for miniature UAVs.
Design/methodology/approach
The paper initially discusses the basic functional elements of UAV, then considers the different challenges faced by UAV designers. The authors have narrowed down the study on obstacle detection and sensing methods for autonomous operation.
Findings
Among the various existing obstacle sensing techniques, on-board vision-based obstacle detection has better scope in the future requirements of miniature UAVs to make it completely autonomous.
Originality/value
The paper gives original review points by doing a thorough literature survey on various obstacle sensing techniques used for UAVs.
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Robert Osei-Kyei, Vivian Tam, Ursa Komac and Godslove Ampratwum
Urban communities can be faced with many destructive events that can disrupt the daily functioning of activities and livelihood of people living in the communities. In this…
Abstract
Purpose
Urban communities can be faced with many destructive events that can disrupt the daily functioning of activities and livelihood of people living in the communities. In this regard, during the last couple of years, many governments have put a lot of efforts into building resilient urban communities. Essentially, a resilient urban community has the capacity to anticipate future disasters, prepare for and recover timely from adverse effects of disasters and unexpected circumstances. Considering this, it is therefore important for the need to continuously review the existing urban community resilience indicators, in order to identify emerging ones to enable comprehensive evaluation of urban communities in the future against unexpected events. This study therefore aims to conduct a systematic review to develop and critically analyse the emerging and leading urban community resilience indicators.
Design/methodology/approach
Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRSIMA) protocol, 53 journal articles were selected using Scopus. The selected papers were subjected to thorough content analysis.
Findings
From the review, 45 urban community resilience indicators were identified. These indicators were grouped into eight broad categories namely, Socio-demographic, Economic, Institutional Resilience, Infrastructure and Housing Resilience, Collaboration, Community Capital, Risk Data Accumulation and Geographical and Spatial characteristics of community. Further, the results indicated that the U.S had the highest number of publications, followed by Australia, China, New Zealand and Taiwan. In fact, very few studies emanated from developing economies.
Originality/value
The outputs of this study will inform policymakers, practitioners and researchers on the new and emerging indicators that should be considered when evaluating the resilience level of urban communities. The findings will also serve as a theoretical foundation for further detailed empirical investigation.
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José Francisco Villarreal Valderrama, Luis Takano, Eduardo Liceaga-Castro, Diana Hernandez-Alcantara, Patricia Del Carmen Zambrano-Robledo and Luis Amezquita-Brooks
Aircraft pitch control is fundamental for the performance of micro aerial vehicles (MAVs). The purpose of this paper is to establish a simple experimental procedure to calibrate…
Abstract
Purpose
Aircraft pitch control is fundamental for the performance of micro aerial vehicles (MAVs). The purpose of this paper is to establish a simple experimental procedure to calibrate pitch instrumentation and classical control algorithms. This includes developing an efficient pitch angle observer with optimal estimation and evaluating controllers under uncertainty and external disturbances.
Design/methodology/approach
A wind tunnel test bench is designed to simulate fixed-wing aircraft dynamics. Key elements of the instrumentation commonly found in MAVs are characterized in a gyroscopic test bench. A data fusion algorithm is calibrated to match the gyroscopic test bench measurements and is then integrated into the autopilot platform. The elevator-angle to pitch-angle dynamic model is obtained experimentally. Two different control algorithms, based on model-free and model-based approaches, are designed. These controllers are analyzed in terms of parametric uncertainties due to wind speed variations and external perturbation because of sudden weight distribution changes. A series of experimental tests is performed in wind-tunnel facilities to highlight the main features of each control approach.
Findings
With regard to the instrumentation algorithms, a simple experimental methodology for the design of optimal pitch angle observer is presented and validated experimentally. In the context of the platform design and identification, the similitude among the theoretical and experimental responses shows that the platform is suitable for typical pitch control assessment. The wind tunnel experiments show that a fixed linear controller, designed using classical frequency domain concepts, is able to provide adequate responses in scenarios that approximate the operation of MAVs.
Research limitations/implications
The aircraft orientation observer can be used for both pitch and roll angles. However, for simultaneousyaw angle estimation the proposed design method requires further research. The model analysis considers a wind speed range of 6-18 m/s, with a nominal operation of 12 m/s. The maximum experimentally tested reference for the pitch angle controller was 20°. Further operating conditions may require more complex control approaches (e.g. scheduling, non-linear, etc.). However, this operating range is enough for typical MAV missions.
Originality/value
The study shows the design of an effective pitch angle observer, based on a simple experimental approach, which achieved locally optimum estimates at the test conditions. Additionally, the instrumentation and design of a test bench for typical pitch control assessment in wind tunnel facilities is presented. Finally, the study presents the development of a simple controller that provides adequate responses in scenarios that approximate the operation of MAVs, including perturbations that resemble package delivery and parametric uncertainty due to wind speed variations.
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Robert Osei-Kyei, Godslove Ampratwum, Ursa Komac and Timur Narbaev
The world is reeling from the effects of climate change with increased extreme precipitation. Flooding is amongst the most recurring and devastating natural hazards, impacting…
Abstract
Purpose
The world is reeling from the effects of climate change with increased extreme precipitation. Flooding is amongst the most recurring and devastating natural hazards, impacting human lives and causing severe economic damage. This paper aims to conduct a systematic review to critically analyse the most reported and emerging flood disaster resilience indicators.
Design/methodology/approach
A total of 35 papers were selected through a systematic process using both Web of Science and Scopus databases. The selected literature was subjected to a thorough thematic content analysis.
Findings
From the review, 77 emerging flood disaster resilience assessment indicators were identified. Furthermore, based on the individual meanings and relationships of the derived indicators, they were further categorized into six groups, namely, physical, institutional, social, psychological, ecology and economic. More also, it was identified that most of the selected publications have used objective resilience measurement approaches as opposed to subjective resilience measurement approaches.
Originality/value
The generated list of flood disaster resilience indicators will provide insights into the capacities which can be improved to enhance the overall resilience to flood disasters in communities.
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Sandar Win and Alexander Kofinas
Many transition economies are former socialist planned economies and have undergone market reforms of their financial sector to signal their transition towards democracy. However…
Abstract
Purpose
Many transition economies are former socialist planned economies and have undergone market reforms of their financial sector to signal their transition towards democracy. However, governments in these countries have been reluctant to relinquish the pre-existing controls on economy and have adopted nuanced and sophisticated approaches to retain control. In such context, scholars may find it challenging to investigate the role played by the state in the success or failure of attempted market reforms. This work investigates the different forms of state-induced accounting controls that may preserve the status quo within the economy during transition, using Myanmar as an example.
Design/methodology/approach
The authors adopted a longitudinal qualitative research method aiming to reveal the very processes and mechanisms used by the banks and their evolution over time. This method is in accordance with the historical institutionalist perspective that they have applied within this research.
Findings
The authors found that the Myanmar government embarked on the privatisation of their financial sector from 1990 to 2016 as a major public sector reform initiative. Under the guise of market reforms, it used both state-led and market-led controls to emulate and retain the socialist banking model where banks are used to fund the immediate government's budget deficits. This created a series of intended and unintended consequences, resulting in the ultimate failure of the government's market reforms.
Research limitations/implications
Previously, research on public sector management accounting in emerging economies was not relying consistently on using theory. The relative limited theorisation led to gaps when attempting to understand and explain the opaque forms of state control mechanisms in transition economies. By applying historical institutionalist perspective, and a more theory-driven, reflective approach to the interpretation of the data collected, the authors have provided a deeper insight and understanding on how different forms of state controls can emerge, adapt and persist in transition economies such as Myanmar.
Practical implications
The authors demonstrated that though the state may have implemented market reforms to signal regimes change, this does not necessarily mean that the government has relinquished their control on the economy. The state could take a more sophisticated, covert approach towards state controls leading to both intended and unintended consequences. Thus, even if the state's preferences change, the decisions cannot be easily reversed, as path-dependent state controls may have become pervasive affecting any further institutional and policy developments. Thus, the authors suggest that governments in both transition and developed economies should be cautious when enacting regulations on corporate control.
Originality/value
In this paper, the authors have applied a historical institutional perspective in their analysis instead of the more widely used sociological, institutionalist approach. This allowed authors to harness rich longitudinal data indicating that market reforms and their success or failure should be examined as an ongoing process rather than a completed action. This is especially important in transition economies where the state may be unwilling to renounce the existing controls on the industry and may resort to more opaque forms of state control, eventually obstructing the intended reforms.