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The purpose of this paper is to present issues and challenges of scheduled maintenance task development within the maintenance review board (MRB) process, and to find potential areas of improvement in the application of the MSG‐3 methodology for aircraft systems.

The issues and challenges as well as potential areas of improvement have been identified through a constructive review that consists of two parts. The first part is a benchmarking between the Maintenance Steering Group (MSG‐3) methodology and other established and documented versions of reliability‐centred maintenance (RCM). This benchmarking focuses on the MSG‐3 methodology and compares it with some RCM standards to identify differences and thereby find ways to facilitate the application of MSG‐3. The second part includes a discussion about methodologies and tools that can support different steps of the MSG‐3 methodology within the framework of the MRB process.

The MSG‐3 methodology is closely related to the RCM methodology, in which the anticipated consequences of failure are considered for risk evaluation. However, MSG‐3 considers neither environmental effects of failures nor operational consequences of hidden failures. Furthermore, in MSG‐3, the operational check (failure‐finding inspection) is given priority before all other tasks, whereas in RCM it is considered as a default action, where there is no other applicable and effective option. While RCM allows cost‐effectiveness analysis for all failures that have no safety consequences, MSG‐3 just allows it for failures with economic consequences. A maintenance program that is established through the MRB process fulfils the requirements of continuous airworthiness, but there is no foundation to claim that it is the optimal or the most effective program from an operator's point‐of‐view. The major challenge when striving to achieve a more effective maintenance program within the MRB process is to acquire supporting methodologies and tools for adequate risk analysis, for optimal interval assignments, and for selection of the most effective maintenance task.

The paper presents a critical review of existing aircraft scheduled maintenance program development methodologies, and demonstrates the differences between MSG‐3 and other RCM methodologies.

This study presents a systematic framework for maintenance strategy development of manufacturing process machinery. The framework is developed based on the reliability-centred maintenance (RCM) approach to minimise the high downtime of a production line, thus increasing its reliability and availability. A case study of a production line from the ghee and soap manufacturing industry in Taiz, Yemen, is presented for framework validation purposes. The framework provides a systematic process to identify the critical system(s) and guide further investigation for functional significant items (FSIs) based on quantitative and qualitative analyses before recommending appropriate maintenance strategies and specific tasks.

The proposed framework integrates conventional RCM procedure with the fuzzy computational process to improve FSIs criticality estimation, which is the main part of failure mode effect criticality analysis (FMECA) applications. The framework consists of four main implementation stages: identification of the critical system(s), technical analysis, Fuzzy-FMECA application for FSIs criticality estimation and maintenance strategy selection. Each stage has its objective(s) and related scientific techniques that are applied to systematically guide the framework implementation.

The proposed framework validation is summarised as follows. The first stage results demonstrate that the seaming system (top and bottom systems) caused 50% of the total production line downtime, indicating it is a critical system that requires further analysis. The outcomes of the second stage provide significant technical information on the subject (seaming system), helping team members to identify and understand the structure and functional complexities of the seaming system. This stage also provides a better understanding of how the seaming system functions and how it can fail. In stage 3, the application of FMECA with the fuzzy computation integration process presents a systematic way to analyse the failure mode, effect and cause of items (components of the seaming system). This stage also includes items’ criticality estimation and ranking assessment. Finally, stage four guides team members in recommending the appropriate countermeasures (maintenance strategies and task selection) based on their priority level.

This paper proposes an original maintenance strategies development framework based on the RCM approach for production system equipment. Specifically, it considers a fuzzy computational process based on the Gaussian function in the third stage of the proposed framework. Adopting the fuzzy computational process improves the risk priority number (RPN) estimation, resulting in better criticality ranking determination. Another significant contribution is introducing an extended item criticality ranking assessment process to provide maximum levels of criticality item ranking. Finally, the proposed RCM framework also provides detailed guidance on maintenance strategy selection based on criticality levels, unique functionality and failure characteristics of each FSI.

This study focuses on the application of reliability-centered maintenance (RCM) to a textile industry steam boiler. The study aims to demonstrate the development and application of RCM to a steam boiler used in the textile industry.

RCM is a structured process that develops maintenance activities needed on physical resources in their operational environment to realize their inherent reliability by logically incorporating an appropriate mixture of reactive, preventive, condition-based and proactive maintenance methods. A detailed analysis of the RCM approach is presented to develop preventive maintenance (PM) program and improve the reliability and availability of the steam boiler system.

The research reveals that the identification of PM tasks is a good indicator of the PM program's efficiency and can serve as an important maintenance-related downtime source. It is also discovered that the majority of maintenance programs that claim to be proactive are, in fact, reactive. This article also shows how RCM may be successfully implemented to any system, resulting in increased system reliability.

The paper focuses on a pilot study of the development and implementation of the RCM technique to a textile industry steam boiler. It is suggested that the developed RCM model can be applied to the entire plant.

The paper presents a comprehensive RCM model framework as well as an RCM decision framework, providing maintenance managers and engineers with a step-by-step approach to RCM implementation. The proposed framework is significant in that it may be utilized for both qualitative and quantitative analysis at the same time.

ORGANIZED by the Aerospace Industries Division of the Institution of Mechanical Engineers, this seminar addressed the airworthiness concepts with the views of regulatory authorities, manufacturers and operators being aired so that a complete picture was obtained of all aspects of the process. Introduced by Alistair Cumming, engineering director of British Airways, the viewpoint of an authority was presented by the head of maintenance approvals of the CAA, A T Dalton, who first spoke of the setting of aircraft maintenance targets. Much of the compliance with design requirements of a large aircraft in the UK that is necessary is concerned with structural and systems testing and the production of the system safety assessment (SSA). The majority of tasks produced from the SSA are replacement of parts, inspection/servicing or system/monitoring. The first two of these categories have been in use for some time but the third group of activities shows a need for reliability programmes for aircraft systems and components. The CAA operating standards appraisal programme (OSAP) has been established whose purposes are to identify operators whose systems and standards are consistently good and for whom routine inspections might be relaxed.

International Business, Entrepreneurship.

This case has been used previously in an international business strategy module on MA courses at Kozminski University, Poland.

The case details Audioteka’s (a Polish audiobook company) history between 2007 and 2013, from the perspective of Marcin, one of the co-founders. The company was founded in 2008 by Marcin Beme and Blazej Kukla and internationalized soon after. Marcin was an experienced entrepreneur, while Blazej was a sound engineer. Both sought to combine their complementary skills and experience to start a business aimed at selling audio recordings. The case is divided into Parts (A) and (B) and is designed to teach international entrepreneurship, lying at the intersection of international business and entrepreneurship. Part (A) is set in 2011 and tracks the company’s evolution from the conception of an idea to establishing a start-up and developing a product. Part (B) is set in 2013 and covers early foreign expansion between 2011 and 2013. The case is focused on the challenges that Marcin faces when developing Audioteka and expanding abroad. It allows students to understand the decision-making logic of an international new venture (INV), choices made and execution while internationalizing. Students will be able to explore how a company adapts its product; how it enters foreign markets; how it overcomes the liabilities of foreignness, smallness, newness and outsidership through establishing partnerships with big companies (telecoms, automakers); and how it appreciates the risks involved in this process.

This case is the basis for a class discussion rather than for illustrating either effective or ineffective handling of a managerial situation. From this case, MA students will learn how an entrepreneurial firm makes strategic decisions and becomes international. The first learning outcome is to evaluate the concepts of liability of origin, foreignness, outsidership, smallness and newness, and to explore ways of overcoming them. Second, the expected learning outcome is to assess differences between the Uppsala model of internationalization and born-global/INV phenomenon. Third, students, by examining particular foreign market-entry modes, are expected to evaluate their advantages and disadvantages. Finally, students are expected to understand the concept of “effectuation” and apply it to the decision-making process in early internationalization.

CSS 5: International Business.

Sound design, planning and monitoring is critical to the operational and financial success of today′s sophisticated manufacturing and non‐manufacturing systems. Owing to their increasing complexity, discrete‐event simulation is becoming the most acceptable tool to aid planning the design and management of production and operations. This growing acceptance has led to the development of many simulators. Two fundamental criteria enable assessment of the suitability of these simulations in complex environments. First, the sophistication of their modelling capability to handle a wide range of problematic situations and second, ease of use. These two considerations, however, tend to conflict; resulting in flexible simulators being difficult to use and vice versa. DSSL II is an advanced simulation methodology with a well defined and user‐friendly modelling strategy. It has been devised to offer a versatile approach in modelling today′s sophisticated systems and policies. Features incorporated include a schematic modelling concept to represent the operational logic of systems, a set of software modules and an associated logical structure. Using the logical structure, the modules are combined to transform the concept of the schematic model into a representative computer program. Using DSSL II, models of manufacturing and non‐manufacturing systems are constructed readily to provide accurate and trustworthy answers to essential “what‐if” questions posed by decision makers, to determine which out of several scenarios would be the most appropriate. The purpose of this paper is to present the concepts and techniques employed by DSSL II. A simple case study and an example of a real industrial application are given in order to demonstrate its features and potential.

The purpose of this paper is to design multiplexers (MUXs) based on ternary half subtractor and full subtractor using carbon nanotube field-effect transistors.

Conventionally, the binary logic functions are developed by using the binary decision diagram (BDD) systems. Each node in BDD is replaced by 2:1 MUX to implement the digital circuits. Similarly, in the ternary decision diagram, each node has to be replaced by 3:1 MUX. In this paper, ternary transformed BDD is used to design the ternary subtractors using 2:1 MUXs.

The performance of the proposed ternary half subtractor and full subtractor using the 2:1 MUX are compared with the 3:1 MUX-based ternary circuits. It has been observed that the delay, power and power delay product values are reduced, respectively, by 67.6%, 84.3%, 94.9% for half subtractor and 67.7%, 70.1%, 90.3% for full subtractor. From the Monte Carlo simulations, it is observed that the propagation delay and power dissipation of the proposed subtractors are increased by increasing the channel length due to process variations. The stability test is also performed and observed that the stability increases as the channel length and diameter are increased.

The proposed half subtractor and full subtractor show better performance over the existing subtractors.

Spaciousness is defined as “the feeling of openness or room to wander” that has been affected by various physical factors. The purpose of this paper is to assess the spaciousness of space to determine how spacious the space is. Furthermore, the study intends to propose a fuzzy-based model to assess the degree of spaciousness in terms of physical parameters such as area, proportion, the ratio of window area to floor area and color value.

Fuzzy logic is the most appropriate mathematical model to assess uncertainty using nonhomogeneous variables. In contrast to conventional methods, fuzzy logic depends on partial truth theory. MATLAB Fuzzy Logic Toolbox was used as a computational model including a fuzzy inference system (FIS) using linguistic variables called membership functions to define parameters. As a result, fuzzy logic was used in this study to assess the spaciousness degree of design studios in universities in the Iraqi Kurdistan region.

The findings of the presented fuzzy model show the degree to which the input variables affect a space perceived as larger and more spacious. The relationship between parameters has been represented in three-dimensional surface diagrams. The positive relationship of spaciousness with the area, window-to-floor area ratio and color value has been determined. In contrast, the negative relationship between spaciousness and space proportion is described. Moreover, the three-dimensional surface diagram illustrates how the changes in the input values affect the spaciousness degree. Besides, the improvement in the spaciousness degree of the design studio increases the quality learning environment.

This study attempted to assess the degree of spaciousness in design studios. There has been no attempt carried out to combine educational space learning environments and computational methods. This study focused on the assessment of spaciousness using the MATLAB Fuzzy Logic toolbox that has not been integrated so far.

System dynamics (SD) is emerging as a powerful approach to understand, analyse, simulate and predict complex and dynamic business processes. In particular, it is true in the process of business model innovation (BMI) and not only as a computational approach. Due to the visual and diagrammatic tools employed by SD, innovation managers overcome humans' mental limitations and improve knowledge management in the BMI. This paper discloses the value of SD's visual tools, i.e. causal loop diagrams and stock and flow diagrams, to contribute to the “Knowldege Visualization” research line, and promote the application of SD as a powerful approach to support decisions in BMI.

Given the explorative nature and the “how” question driving the research, the methodology involved is a single, holistic case study. In particular, the case is about a business model (BM) diversification, in which an information and communication technology service provider has added to its existing business model a new BM based on a digital multi-sided platform, for passengers transportation.

The diagrammatic tools of SD, that is causal loop diagrams and stock and flow diagrams, allowed entrepreneurs to overcome the complexity of the business parameters concurring in the design of the BM.

The value of this research is in the exploratory approach and in the originality of the perspective by which SD is analysed: the visual knowledge perspective.

The traditional methods for process modeling emphasize the process workflow considerations at the cost of the associated process structure and resource communication. In the real process world, however, all these aspects are integrated and appear simultaneously: the workflows are driven by communication across the structure of resources. The aim of this paper is to explore a new approach based on an innovative, two‐dimensional view of the process world in an enterprise, integrating the workflow, the structure, and the communication from the beginning on.

Contrary to the traditional methods, the workflow diagrams are not directly designed by the process modeler, but rather they are automatically generated from the connectivity of specified resource communication. The modular documentation contains text and graphic information about the entire process world (structure of process resources, structure of process workflows, resource communication and interaction, communication through internal/external interfaces).

A new systematic approach to modular, process‐oriented enterprise description has been developed. Its two‐dimensional model allows an integrated visualization of the entire process world. The resulting process documentation is absolutely consistent and of very high quality. The user‐friendly access to information is made possible by clear interdependencies of process‐defining objects embedded in a relational documentation model. An update of the complete documentation can be performed automatically from the common database. The successful software implementation of the prototype application and its use in small customer projects demonstrate the practical feasibility of the two‐dimensional approach.

The two‐dimensional process modeling (2DPM) is a new systematic approach to modular process‐oriented enterprise description. A software implementation based on the underlying model together with professional programming tools and principles would be necessary to arrive at a marketable product.