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Major changes of an aircraft configuration are conducted during the early design stage. It is important to include the airworthiness regulations at this stage while there is extensive freedom for designing. The purpose of this paper is to introduce an efficient design framework that integrates airworthiness guidelines and documentation at the early design stage.

A new design and optimization process is proposed that logically includes the airworthiness regulations as design parameters and constraints by constructing a certification database. The design framework comprises requirements analysis, preliminary sizing, conceptual design synthesis and loads analysis. A design certification relation table (DCRT) describes the legal regulations in terms of parameters and values suitable for use in design optimization.

The developed framework has been validated and demonstrated for the design of a Federal Aviation Regulations (FAR) 23 four-seater small aircraft. The validation results show an acceptable level of accuracy to be applied during the early design stage. The total mass minimization problem has been successfully solved while satisfying all the design requirements and certification constraints specified in the DCRT. Moreover, successful compliance with FAR 23 subpart C is demonstrated. The proposed method is a useful tool for design optimization and compliance verifications during the early stages of aircraft development.

The new certification database proposed in this research makes it simpler for engineers to access a large amount of legal documentation related to airworthiness regulations and provides a link between the regulation text and actual design parameters and their bounds.

The proposed design optimization framework integrates the certification database that is built of several types of legal documents such as regulations, advisory circulars and standards. The Engineering Requirements and Guide summarizes all the documents and design requirements into a single document. The DCRT is created as a summary table that indicates the design parameters affected by a given regulation(s), the design stage at which the parameter can be evaluated and its value bounds. The introduction of the certification database into the design optimization framework significantly reduces the engineer’s load related for airworthiness regulations.

This study aims to investigate the impact of coronavirus disease 2019 (COVID-19) on the relationship between buyer firms' corporate social responsibility (CSR) activities toward business partners, such as suppliers, and firm value. The study further explores the role of ownership structure in shaping this relationship.

The authors employ a difference-in-differences (DID) regression method to distinguish between the periods before and during the COVID-19 crisis. The authors utilize data from firms listed on the Korean stock market between 2013 and 2020.

The results show that CSR activities for suppliers have a positive impact on the value of buyer firms. Furthermore, this positive relationship is amplified during the COVID-19 period. In addition, the study finds that the positive relationship is more prominent in samples with higher ownership by controlling shareholders or foreign investors.

Overall, this study makes a valuable contribution to the existing literature by examining the positive effects of CSR activities on firm value and by shedding light on the role of ownership structure in influencing these effects. Additionally, the study emphasizes the significance of CSR activities for business partners in mitigating supply chain disruptions during the COVID-19 pandemic.

The purpose of this paper is to study the conceptual design and optimisation of a compound gyroplane. A study of a compound gyroplane configuration and its characteristics was performed to develop a sizing program.

The vertical takeoff and landing capabilities of a helicopter are particularly important. The need for efficient hover and the effectiveness of forward flight in the helicopter can cause conflicts within the design process. The designers usually wish to increase the helicopter's maximum forward speed. Recently, the compound aircraft is one of the concepts considered for the purpose of expanding the flight envelope of rotorcraft. The study of the compound gyroplane showed its advance capabilities for this purpose. Understanding its characteristics, a number of calculations are conducted to implement a sizing program for compound gyroplanes based on the conventional helicopter sizing process.

The results of the sizing program were validated using existing aircraft data such as the Challis Heliplane, Carter Copter, FB‐1 Gyrodyne, and Jet Gyrodyne. The program is appropriate to size a compound gyroplane at the conceptual design phase. An optimisation study was also performed to enhance sizing results. The compromise between the rotor lift sharing factor and the ratio of the wing span (Bw) to rotor diameter (D) was solved by choosing the total gross weight (TOGW) as the objective function, while the design variables are compromising factors. The optimum results showed that the TOGW of all four kinds of compound gyroplanes was considerably reduced.

A conceptual sizing program for unconventional compound aircraft was developed. The study showed that an optimum design process is necessary to enhance the sizing results.

This chapter examines the optimal choice of managerial incentives for firm owners in a multi-stage oligopoly. In our three-stage owner-manager game, characterized by pre-product launch investments such as advertising, the owners never tell their managers to maximize profits. The contract to maximize profits is not a self-representational Nash Equilibrium. When advertising is a strategic substitute, the owners induce their managers to advertise more aggressively than is necessary for profit maximization, even if they only care about profits. When advertising is a strategic complement, however, the strategic effects are reversed.

Rotor performance analysis and design are complex due to the wide variation in flow characteristics. Design tools that can rapidly and accurately compute aerofoil data are needed for rotorcraft design and analysis purposes. The purpose of this paper is to describe a process which has been developed that effectively automates the generation of two‐dimensional (2D) aerofoil characteristics tables.

The process associates a number of commercial software packages and in‐house codes that employ diverse methodologies, including the Navier‐Stokes equation‐solving method, the high‐order panel method and Euler equations solved with the fully coupled viscous‐inviscid interaction (VII) method. The paper describes the development of a general automated generation method that extends from aerofoil shape generation to aerofoil characteristic analysis. The generated data are stored in C81 aerofoil characteristics tables for use in comprehensive rotorcraft analysis codes and rotor blade design. In addition, the methodology could be easily applied for fixed‐wing analysis and design, especially for transonic aircraft.

The method is demonstrated to achieve aerofoil characteristics quickly and accurately in automated process. Calculations for the SC1095 aerofoil section are presented and compared with existing experimental C81 data and previous studies.

The development of C81 tables is of interest to industry as they seek to update their airfoil tables as new designs. Automated processes to achieve this are helpful and applicable.

The paper presents an effective automated process to generate aerofoil characteristics tables quickly, and accurately.

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.

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.

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.

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.

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.

The purpose of this paper is to study the consideration of uncertainty from analysis modules for aircraft conceptual design by implementing uncertainty-based design optimization methods. Reliability-Based Design Optimization (RBDO), Possibility-Based Design Optimization (PBDO) and Robust Design Optimization (RDO) methods were developed to handle uncertainties of design optimization. The RBDO method is found suitable for uncertain parameters when sufficient information is available. On the other hand, the PBDO method is proposed when uncertain parameters have insufficient information. The RDO method can apply to both cases. The RBDO, PBDO and RDO methods were considered with the Multidisciplinary Design Optimization (MDO) method to generate conservative design results when low fidelity analysis tools are used.

Methods combining MDO with RBDO, PBDO and RDO were developed and have been applied to a numerical analysis and an aircraft conceptual design. This research evaluates and compares the characteristics of each method in both cases.

The RBDO result can be improved when the amount of data concerning uncertain parameters is increased. Conversely, increasing information regarding uncertain parameters does not improve the PBDO result. The PBDO provides a conservative result when less information about uncertain parameters is available.

The formulation of RDO is more complex than other methods. If the uncertainty information is increased in aircraft conceptual design case, the accuracy of RBDO will be enhanced.

This research increases the probability of a feasible design when it considers the uncertainty. This result gives more practical optimization results on a conceptual design level for fabrication.

It is RBDO, PBDO and RDO methods combined with MDO that satisfy the target probability when the uncertainties of low fidelity analysis models are considered.

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.

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.

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.

The manufacturing (practical factors) could be considered at an early stage of the rotor blades design.

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.

The purpose of this paper is to compare customer experience (CE) between digital and traditional South Korean bank users and its relationship with customer satisfaction (CS).

A survey of bank customers was conducted, and an ANOVA test was performed to compare the means of CS between digital and traditional bank (TB) users as well as four dimensions of CE, such as usefulness, convenience, employee-customer engagement (ECE) and security. The ordinal regression analysis was also performed to test the moderation effect of digital bank (DB) use on the relationship between CE and satisfaction.

The means of usefulness were higher among DB users than TB users. By contrast, ECE and security means were lower for digital than TB users. The ordinal regression analysis indicated that DB use had a moderating effect on the relationship between convenience and CS and the relationship between ECE and CS. DB use encouraged increased positive relationships between convenience and CS, and moderated the relationship between ECE and CS in a negative direction.

ECE and security for DBs is weak. Therefore, bank executives need to improve these areas through real-time customer services and adding authentication procedures.

Unlike previous studies, this study proposed a model that reveals differences in CE between traditional and DB users. It explored the effects of CE on CS to contribute to the continued development of South Korean DBs.