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The purpose of this paper is to establish the dynamics model of spacecraft during deployment of oblique solar panel using Auto Dynamic Analysis of Mechanical System (ADAMS) and to study the attitude motion of the spacecraft system during the oblique solar panel deployment.

For the case of an oblique solar panel on spacecraft, the dynamics virtual prototype model of deployment of oblique solar panels on spacecraft is established and the dynamics simulation is carried out using ADAMS. The effects of solar panel deployment on the attitude motion of spacecraft with different oblique angles are studied and the attitude motion regularities of spacecraft system are discussed. First, the effects on attitude motion of spacecraft are compared between the normal solar panel deployment and oblique solar panel deployment on a spacecraft. Then the attitude motion of spacecraft during the deployment of solar panel with different oblique angles on spacecraft is studied.

The effects of oblique angle of solar panel deployment on the attitude motion of spacecraft are significant in yaw axis. The bigger the oblique angle, the bigger the changes of yaw angle of spacecraft. However, the bigger the oblique angle, the smaller the changes of roll angle of spacecraft. The effects of oblique angle on pitch angle of spacecraft are slight.

Providing a practical method to study the attitude motion of spacecraft system during deployment of solar panel and improving the engineering application of spacecraft system, which put forward up spacecraft system to the practical engineering.

The paper is a useful reference for engineering design of a spacecraft attitude control system and ground text.

The purpose of this paper is to establish the dynamics model of a Z-folded PhoneSat considering hinge friction and to investigate the influence of disturbances, such as friction, stiffness asymmetry, deployment asynchronicity and initial disturbance angular velocity, on the attitude of PhoneSat during and after deployment.

For the Z-folded PhoneSat, the dynamics model considering hinge friction is established and the dynamics simulation is carried out. The effects of friction, stiffness asymmetry, deployment asynchronicity and initial disturbance angular velocity on the attitude motion of the PhoneSat are studied and the attitude motion regularities of the PhoneSat considering the disturbance factors mentioned above are discussed.

Friction has a main contribution to reducing the oscillation of attitude motion and damping out the residual oscillation, ultimately decreasing the deployment time. An increasing length of deployment time is required with the increasing stiffness asymmetry and time difference of asynchronous deployment, which also have slight disturbances on the attitude angle and angular velocity of PhoneSat after the deployment. The initial disturbance angular velocity in the direction of deployment would be proportionally weakened after the deployment, whereas initial disturbance angular velocity in other direction induces angular velocities of other axes, which dramatically enhances the complexity of attitude control.

The paper is a useful reference for engineering design of small satellites attitude control system.

The purpose of this study is to investigate the deployment and control of cable-driven flexible solar arrays.

First, dynamic model of the system is established by using the Jourdain’s velocity variation principle and the single direction recursive construction method, including the dynamic equation of a single flexible body, the kinematical recursive relation of two adjacent flexible bodies and the dynamic equation of the solar array system. Then, the contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A three-dimensional revolute joint model is introduced and discussed in detail. Finally, a proportion-differentiation (PD) controller is designed to control the drift of the system caused by the deployment.

Simulation results show that the proposed model is effective to describe the deployment of flexible solar arrays, joint friction may affect the dynamic behavior of the system and the PD controller can effectively eliminate the spacecraft drift.

This model is useful to indicate the dynamics behavior of the solar array system with friction.

The relationship between ideal constraint force and Lagrange multipliers is derived. The contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A PD controller is designed to control the drift of the system caused by the deployment of solar arrays.

The aim of this paper is to look at the extent to which the bandwagon effect played a part in digital subscriber line (DSL) broadband adoption combined with the regulatory measures, the slowdown in the cable industry and the changes within the telecommunications industry in the United Kingdom (UK). The dynamics of broadband deployment, broadband adoption against a real‐world supply‐demand equation and the factors that influenced the outcome in the UK are examined in detail.

This paper combines historic facts and socio‐economic analysis done from archival research and interview material to examine the outcome in which the less‐heralded copper DSL technology outpaced cable broadband adoption. The analysis delves into the influence of the bandwagon effect and the two types of outcome associated with it i.e. network externalities and the complementary bandwagon effects.

The paper argues that the deployment of broadband technologies in the UK has not taken place solely on the merits of the technology or factors such as speed, end‐user demand and costs. A combination of factors related to regulatory decisions, status of industry finances, commercial expediency, short‐term technical benefits and the bandwagon effect are argued to be at work.

The paper is useful for historians, policy makers, regulators and communications industry analysts given its focus on broadband deployment in the UK in correlation to the bandwagon economics.

In many organisations, the alignment between information technology (IT) and business is viewed as an important catalyst for the organisation's effectiveness and efficiency towards achieving a competitive advantage. Yet, a shared understanding between business and IT (the EA included) remains an issue in many organisations. The organisational structure affects the alignment between business and IT units. Conversely, a lack of alignment of both components (IT and business units) impedes organisations' capacity to increase and improve their productivity. Many studies have been conducted in the area of IT, EA and the organisational structure. There is, however, little evidence of work conducted in exploring the interface between organisational structure and EA prior to this study. The paper aims to discuss these issues.

A case-study research approach was employed to investigate the impact of organisational structure in the deployment of EA in organisations. Qualitative data were collected through semi-structure technique. The analysis was carried out, using structuration theory.

The magnified data revealed some of unforeseen factors impeding the success of the EA deployment in the organisation.

The work is original, and it has not been submitted or published anywhere else.

The purpose of this paper is to develop a generic framework for hybrid (integrated deployment of system dynamics and discrete event simulation) simulation which can be applied in the healthcare domain.

As hybrid simulation in an organisational context is a new topic with limited available data on deployment of hybrid simulation in organisational context, an inductive approach has been applied. On the basis of knowledge induced from literature, a generic conceptual framework for hybrid simulation has been developed. The proposed framework is demonstrated using an explanatory case study comprising an accident and emergency (A&E) department.

The framework provided detailed guidance for the development of a hybrid model of an A&E case study. Findings of this case study suggest that the hybrid model was more efficient in capturing behavioural impact on operational performances.

The framework is limited to only SD and DES; as agent‐based is another simulation method which is emerging as a promising tool for analysing problems such as spread of infectious diseases in healthcare context, inclusion of this into the framework will enhance the utility of the framework.

This framework will aid in the development of hybrid models capable of comprehending both detail as well as dynamic complexity, which will contribute towards a deeper understanding of the problems, resulting in more effective decision making.

It is expected that this research will encourage those engaged in simulation (e.g. researchers, practitioners, decision makers) to realise the potential of cross‐fertilisation of the two simulation paradigms.

Currently, there is no conceptual framework which provides guidance for developing hybrid models. In order to address this gap, this paper contributes by proposing a conceptual framework for hybrid simulation for the healthcare domain.

The use of mobile devices in handling our daily activities that involve the storage or access of sensitive data (e.g. on-line banking, paperless prescription services, etc.) is becoming very common. These mobile electronic services typically use a knowledge-based authentication method to authenticate a user (claimed identity). However, this authentication method is vulnerable to several security attacks. To counter the attacks and to make the authentication process more secure, this paper aims to investigate the use of touch dynamics biometrics in conjunction with a personal identification number (PIN)-based authentication method, and demonstrate its benefits in terms of strengthening the security of authentication services for mobile devices.

The investigation has made use of three light-weighted matching functions and a comprehensive reference data set collected from 150 subjects.

The investigative results show that, with this multi-factor authentication approach, even when the PIN is exposed, as much as nine out of ten impersonation attempts can be successfully identified. It has also been discovered that the accuracy performance can be increased by combining different feature data types and by increasing the input string length.

The novel contributions of this paper are twofold. Firstly, it describes how a comprehensive experiment is set up to collect touch dynamics biometrics data, and the set of collected data is being made publically available, which may facilitate further research in the problem domain. Secondly, the paper demonstrates how the data set may be used to strengthen the protection of resources that are accessible via mobile devices.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

This paper aims to develop a system dynamics (SD) model to identify causal relationships among the elements of failure modes and effects analysis (FMEA), i.e. failure modes, effects and causes.

A causal loop diagram (CLD) has been developed based on the results obtained from interdependencies and correlations analysis among the FMEA elements through applying the integrated approach of FMEA-quality function deployment (QFD) developed by Shaker et al. (2019). The proposed model was examined in a steel manufacturing company to identify and model the causes and effects relationships among failure modes, effects and causes of a roller-transmission system.

Findings indicated interactions among the most significant failure modes, effects and causes. Moreover, corrective actions defined to eliminate or relieve critical failure causes. Consequently, production costs decreased, and the production rate increased due to eliminated/decreased failure modes.

The application of CLD illustrates causal relationships among FMEA elements in a more effective way and results in a more precise recognition of the root causes of the potential failure modes and their easy elimination/decrease. Therefore, applying the proposed approach leads to a better analysis of the interactions among FMEA elements, decreased system's failure rate and increased system availability.

The literature review indicated a few studies on the application of SD methodology in the maintenance area, and no study was performed on the causal interactions among FMEA elements through an FMEA-QFD based SD approach. Although the interactions of these elements are significant and helpful in risks ranking, researchers fail to investigate them sufficiently.

Existing innovation frameworks suggest that manufacturing firms have traditionally developed a complementary model of technological innovations comprising process and product innovations (e.g. Oslo Manual). This article presents digital service innovation as a novel form of technological innovation that is capable of enhancing the performance of firms in certain manufacturing industries.

Drawing on technological innovation and digital servitization fields of research, this study argues that digital service innovation, in manufacturing contexts, complements traditional sources of technological innovation, so increasing the profit margins of firms. This effect is significant in industries characterized by business-to-business contexts, high presence of link channels and long product life spans (e.g. manufacturing and computer-based industries). Predictions are tested on a unique sample of 423 Spanish manufacturing firms using parametric (t-test) and nonparametric (fuzzy-set qualitative comparative analysis, fsQCA) approaches.

The results of this analysis show that a necessary condition so that manufacturing firms can increase profits is the deployment of simultaneous process and product innovations. It also reveals that optimal configuration requires that digital service innovation be undertaken, particularly in machinery and computer-based manufacturing industries. Hence, all three sources of technological innovation are brought together in order to reach the highest levels of company performance. The evidence suggests that technological innovation and digital servitization are closely interrelated in highly innovative manufacturing contexts.

This study's originality and value reside in the fact that it reveals the existence of firms incorporating digital service innovation – a new, technological innovation dimension that challenges existing innovation frameworks – to complement traditional technological innovation sources, namely process and product innovation. Moreover, the study conceptualizes and empirically tests the value-adding role of digital services in firms' technological innovation portfolio.