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The main purpose of the paper is to develop model basing on the modified and properly‐adopted Fermi‐Dirac equation which combines proper accuracy with adequate simplicity as well as to show how steady state and transient curves resulting from this model can be applied for solving design task.

The standard Fermi‐Dirac equation was modified and extended. Full performance cycle for the SMA actuator was characterized by double‐valued function describing the actuator activation and the actuator deactivation. All these functions and parameters can be easily determined by analysis of measurement data or with use of Hooke‐Jeeves optimization algorithm.

SMA linear actuator can be used in mechatronic systems as a special non‐standard drive when ultra‐light mass and very simple mechanical construction of power feed system is required. The proposed steady‐state and transient performance curves as well as operation diagram constitute sufficient base for effective designing SMA drive systems.

The greatest disadvantage of a SMA actuator is long time of deactivation resulting from slow self‐cooling process. As far as efficiency is concerned as essential factor for choosing the most suitable linear actuator, there is no sense to take into account a linear SMA actuator because of its very low efficiency.

Designer can use performance curve which determines proper length of SMA actuator and range of its motion. The proposed model can be implemented in SMA drive control unit for controlling position of the actuator.

Similarities between change of martensitic phase during transition process and probability P of electron energy level distribution described by the Fermi‐Dirac two‐variable equation were taken into account. Such an approach seems to express in the most suitable way the physical nature of m‐a transition. The authors decided to extend concept (proposed in Jayender et al.) and to adopt the Fermi‐Dirac equation for describing behaviour of a SMA linear actuator.

Kids get exposed to advertising on social media platforms when they visit them to perform various goals. The purpose of this study is to find out the factors which affect kids' behaviour when the kids encounter advertising on social media and also to establish causal relationships amongst the factors of social media advertising (SMA).

A total of 11 factors of SMA have been identified with the help of experts and the causal relationships amongst the SMA factors have been constructed by the implementation of decision-making trail and laboratory evaluation (DEMATEL). Based on the established relationships, a causal diagram has been also developed to understand the structural nature of interdependence amongst the factors.

DEMATEL technique is based on logical steps, which have assisted in categorising the identified factors into two groups: cause group and effect group. Cause group factors are the reasons for the effect group factors to occur. Customisation, entertainment, information and interactivity have been observed as cause factors whereas, relevance, engagement with SMA, purchase intention, product involvement, advertising value, attitude towards SMA and irritation have been observed as effect factors. Product involvement is found to have the highest level of interaction with all other factors. Information and interactivity are observed to influence all other factors.

Kids possess a limited understanding of the selling intent of advertisers which makes kids vulnerable to advertising. This study supports that the content of the advertisement should be kept in accordance with the need of kids and also suggests that marketers should emphasise cause group factors which derive subsequent consequences on effect group factors. The foremost limitation of this study lies in the process of identifying the factors through expert opinions. The sets of contextual relationships may vary when different experts are considered.

This study strives to identify the factors which affect kids' understanding of SMA and also establishes causal relationships amongst them. This kind of study is unique in state of the art and to the authors' knowledge no significant research has been conducted in India which involves establishment of inter-relationships amongst SMA factors that affect kids' behaviour.

There is a growing awareness on the use of systems approaches to improve patient safety and quality. While earlier studies evaluated the validity of such approaches to identify and mitigate patient safety risks, so far only little attention has been given to their inputs, such as structured brainstorming and use of system mapping approaches (SMAs), to understand their impact in the risk identification process. To address this gap, the purpose of this paper is to evaluate the inputs of a well-known systems approach, failure modes and effects analysis (FMEA), in identifying patient safety risks in a real healthcare setting.

This study was conducted in a newly established adult attention deficit hyperactivity disorder service at Cambridge and Peterborough Foundation Trust in the UK. Three stakeholders of the chosen service together with the facilitators conducted an FMEA exercise along with a particular system diagram that was initially found as the most useful SMA by eight stakeholders of the service.

In this study, it was found that the formal structure of FMEA adds value to the risk identification process through comprehensive system coverage with the help of the system diagram. However, results also indicates that the structured brainstorming refrains FMEA participants from identifying and imagining new risks since they follow the process predefined in the given system diagram.

While this study shows the potential contribution of FMEA inputs, it also suggests that healthcare organisations should not depend solely on FMEA results when identifying patient safety risks; and therefore prioritising their safety concerns.

This study aims to develop an innovative actuator for improving the performance of future aircraft, by adapting the airfoil shape according to the flight conditions. The flap’s camber of a civil regional transportation aircraft’s trailing edge actuated and morphed with the use of shape memory alloys (SMA) actuator technology, instead of the conventional split flap mechanism is studied.

For the flap’s members sizing an efficient methodology is utilised based on finite element (FE) stress analysis combined to analytically formulated design criteria. A mechanical simulation within an FE approach simulated the performance of the moving rib, integrating both aerodynamic loads and SMA phenomenology, implementing Lagouda’s constitutive model. Aim of this numerical simulation is to provide guidelines for further development of the flap. A three-dimensional assembly of the flap is constructed to produce manufacturing drawing and to ensure that during its morphing no interference between the members occurrs. Eventually, the manufactured flap is integrated on a test rig and the experimental characterisations under no and static loads, and dynamic excitation are performed.

Experimental results showed that the rib’s SMA mechanism can adequate function under load providing satisfactory morphing capabilities.

The investigated approach is an internal into the flap mechanism based on the shape memory effect of thin wires. In the developed mechanism, SMA wires are attached to the wing structure, where they function as actuating elements.

This paper aims to get rid of the traditional basic principle of using the motor as the variable stiffness drive source, simplify the structure of the exoskeleton and reduce the quality of the exoskeleton. This paper proposes to use shape memory alloys (SMA) as the variable stiffness drive source.

In this study, SMA is used to construct the active variable stiffness unit, the Brinson constitutive model is used to establish a dynamic model to control the active variable stiffness unit and the above active variable stiffness unit is used to realize the force control function and construct a lightweight, variable stiffness knee exoskeleton.

The dynamic model constructed in this paper can preliminarily describe the phase transformation process of the active variable stiffness unit and realize the variable stiffness function of the knee exoskeleton. The variable stiffness exoskeleton can effectively reduce the driving error under the high-speed walking condition.

The contribution of this paper is to combine SMAs to construct an active variable stiffness unit, build a dynamic model for controlling the active variable stiffness unit and construct a lightweight, variable stiffness knee exoskeleton.

Implementing surface mount technology (SMT) into military systems has not progressed as rapidly as expected. One of the major reasons is the lack of availability of MIL Spec. surface mountable components. Therefore, if one is to realise the benefits of SMT, manufacturing processes must be developed that allow inserted components to be mounted on the same printed wiring board (PWB) with surface mount components (SMCs). Honeywell's Ordnance Division has developed manufacturing processes which allow SMCs to be mounted on both sides of the PWB and inserted components to be mounted on one side of the same PWB. The surface mount solder reflow and wave soldering are performed in a single‐step solder system. This simplifies and reduces the number of manufacturing process steps for this type of surface mount assembly (SMA). This paper describes three major types of SMAs and their complexity levels. Definitions of the SMA types and complexity levels are necessary for selecting production equipment and developing SMA processes. Assembly process limitations are directly related to the SMA type and complexity level. Layout guidelines and processes from solder deposition to cleaning are discussed. Full scale engineering development (FSED) hardware has been fabricated using the single‐step solder process for SMAs with both SMCs and inserted components on the same PWB. The single‐step solder process offers an excellent solution to fabricating electronic assemblies where SMCs and inserted components are mounted on the same PWB. Plans to expand and enhance the first generation SMA fabrication processes to accommodate higher complexity levels are discussed.

The purpose of this paper is the optimisation of shape memory alloy (SMA) spring actuators. The purpose of these actuators is to control active endoscopes. The objective for such endoscopes is to minimize one patient pain during operation.

A range of recently published (1990‐2002) works, which aim to provide models for SMA actuators, do not focus on the simulation and on the design of such actuators. SMAs have two main characteristics, namely the phase change and non‐linear behaviour in each phase. The proposed model is based on a mixed approach combining an Euler‐Bernoulli beam model and a bi‐dimensional finite element model. It allows the modelling of plastic behaviour and drives the phase evolution in the beam cross‐section.

The physical properties of SMAs are described and modelled. A new beam model and a numerical algorithm are proposed. Preliminary results demonstrate the performance of our method on two problems and lead to determine the actuator capability. The resulting actuator model is then integrated into an optimisation process based on genetic algorithms. The overall approach provides a design tool for SMA spring actuator subjected to design constraints.

The proposed method is only validated for our practical purposes. However, we believe that the optimisation methodology may have other implications in structure design.

This paper provides an optimisation approach that is valuable for scientists and engineers in engineering computations.

The purpose of this paper is to actively calibrate power density to match the application requirements with as small an actuator as possible. So, this paper introduces shape memory alloy to design variable stiffness elements. Meanwhile, the purpose of this paper is also to solve the problem of not being able to install sensors on shape memory alloy due to volume limitations.

This paper introduces the design, modeling and control process for a variable stiffness passive ankle exoskeleton, adjusting joint stiffness using shape memory alloy (SMA). This innovative exoskeleton aids the human ankle by adapting the precompression of elastic components by SMA, thereby adjusting the ankle exoskeleton’s integral stiffness. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.

Using SMA as the driving force for stiffness modification in passive exoskeletons introduces several distinct advantages, inclusive of high energy density, programmability, rapid response time and simplified structural design. In the course of experimental validation, this ankle exoskeleton, endowed with variable stiffness, proficiently executed actions like squatting and walking and it can effectively increase the joint stiffness by 0.2 Nm/Deg.

The contribution of this paper is to introduce SMA to adjust the stiffness to actively calibrate power density to match the application requirements. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.

The purpose of this research is to develop a prototype of agent‐based intelligent workflow system for product design collaboration in a distributed network environment.

This research separates the collaborative workflow enactment mechanisms from the collaborative workflow building tools for flexible workflow management. Applying the XML/RDF (resource description framework) ontology schema, workflow logic is described in a standard representation. Lastly, a case study in collaborative system‐on‐chip (SoC) design is depicted to demonstrate the agent‐based workflow system for the design collaboration on the web.

Agent technology can overcome the difficulty of interoperability in cross‐platform, distributed environment with standard RDF data schema. Control and update of workflow functions become flexible and versatile by simply modifying agent reasoning and behaviors.

When business partners want to collaborate, how to integrate agents in different workflows becomes a critical issues.

Agent technology can facilitate design cooperation and teamwork communication in a collaborative, transparent product development environment.

This research establishes generalized flow logic RDF models and an agent‐based intelligent workflow management system, called AWfMS, based on the RDF schema of workflow definition. AWfMS minimizes barriers in the distributed design process and hence increases design cooperations among partners.

Many people suffer from injuries related to their hand. This research aims to focus on the improvement of the previously developed smart glove by using position and force control algorithms. The new smart glove may be used for both physiotherapy and assistance.

The proposed robot uses shape memory alloy (SMA) actuators coupled to an under-actuated tendon-driven mechanism. The proposed device, which is presented as a wearable glove attached to an actuation module, is capable of exerting extremely high forces to grasp objects in various hand configurations. The device’s performance is studied in physiotherapy and object manipulation tasks. In the physiotherapy mode, hand motion frequency is controlled, whereas the grasping force is controlled in the object manipulation mode. To simulate the proposed system behavior, the kinematic and dynamic equations of the proposed system have been derived.

The achieved results verify that the system is suitable to be used as part of a rehabilitation device in which it can flex and extend fingers with accurate trajectories and grasp objects efficiently. Specifically, it will be shown that using six SMA wires with the diameter of 0.25 mm, the proposed robot can provide 45 N gripping force for the patients.

The proposed robot uses SMA actuators and an under-actuated tendon-driven mechanism. The resulted robotic system, which is presented as a wearable glove attached to an actuation module, is capable of exerting extremely high force levels to grasp objects in various hand configurations. It is shown that the motion and exerted force of the robot may be controlled effectively in practice.