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Article
Publication date: 6 September 2024

Nour Mani, Nhiem Tran, Alan Jones, Azadeh Mirabedini, Shadi Houshyar and Kate Fox

The purpose of this study is therefore to detail an additive manufacturing process for printing TiD parts for implant applications. Titanium–diamond (TiD) is a new composite that…

Abstract

Purpose

The purpose of this study is therefore to detail an additive manufacturing process for printing TiD parts for implant applications. Titanium–diamond (TiD) is a new composite that provides biocompatible three-dimensional multimaterial structures. Thus, the authors report a powder-deposition and print optimization strategy to overcome the dual-functionality gap by printing bulk TiD parts. However, despite favorable customization outcomes, relatively few additive manufacturing (AM) feedstock powders offer the biocompatibility required for medical implant and device technologies.

Design/methodology/approach

AM offers a platform to fabricate customized patient-specific parts. Developing feedstock that can be 3D printed into specific 3D structures while providing a favorable interface with the human tissue remains a challenge. Using laser metal deposition, feedstock powder comprising diamond and titanium was co-printed into TiD parts for mechanical testing to determine optimal manufacturing parameters.

Findings

TiD parts were fabricated comprising 30% and 50% diamond. The composite powder had a Hausner ratio of 1.13 and 1.21 for 30% and 50% TiD, respectively. The flow analysis (Carney flow) for TiD 30% and 50% was 7.53 and 5.15 g/s. The authors report that the printing-specific conditions significantly affect the integrity of the printed part and thus provide the optimal manufacturing parameters for structural integrity as determined by micro-computed tomography, nanoindentation and biocompatibility of TiD parts. The hardness, ultimate tensile strength and yield strength for TiD are 4–6 GPa (depending on build position), 426 MPa and 375 MPa, respectively. Furthermore, the authors show that increasing diamond composition to 30% results in higher osteoblast viability and lower bacteria count than titanium.

Originality/value

In this study, the authors provide a clear strategy to manufacture TiD parts with high integrity, performance and biocompatibility, expanding the material feedstock library and paving the way to customized diamond implants. Diamond is showing strong potential as a biomedical material; however, upscale is limited by conventional techniques. By optimizing AM as the avenue to make complex shapes, the authors open up the possibility of patient-specific diamond implant solutions.

Graphical abstarct

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 12 February 2021

Himanshukumar R. Patel and Vipul A. Shah

The two-tank level control system is one of the real-world's second-order system (SOS) widely used as the process control in industries. It is normally operated under the…

Abstract

Purpose

The two-tank level control system is one of the real-world's second-order system (SOS) widely used as the process control in industries. It is normally operated under the Proportional integral and derivative (PID) feedback control loop. The conventional PID controller performance degrades significantly in the existence of modeling uncertainty, faults and process disturbances. To overcome these limitations, the paper suggests an interval type-2 fuzzy logic based Tilt-Integral-Derivative Controller (IT2TID) which is modified structure of PID controller.

Design/methodology/approach

In this paper, an optimization IT2TID controller design for the conical, noninteracting level control system is presented. Regarding to modern optimization context, the flower pollination algorithm (FPA), among the most coherent population-based metaheuristic optimization techniques is applied to search for the appropriate IT2FTID's and IT2FPID's parameters. The proposed FPA-based IT2FTID/IT2FPID design framework is considered as the constrained optimization problem. System responses obtained by the IT2FTID controller designed by the FPA will be differentiated with those acquired by the IT2FPID controller also designed by the FPA.

Findings

As the results, it was found that the IT2FTID can provide the very satisfactory tracking and regulating responses of the conical two-tank noninteracting level control system superior as compared to IT2FPID significantly under the actuator and system component faults. Additionally, statistical Z-test carried out for both the controllers and an effectiveness of the proposed IT2FTID controller is proven as compared to IT2FPID and existing passive fault tolerant controller in recent literature.

Originality/value

Application of new metaheuristic algorithm to optimize interval type-2 fractional order TID controller for nonlinear level control system with two type of faults. Also, proposed method will compare with other method and statistical analysis will be presented.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 14 no. 1
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 3 December 2021

Haris Calgan

This study aims to design and implement a novel tilt integral sliding mode controller and observer for sensorless speed control of a permanent magnet synchronous motor (PMSM).

Abstract

Purpose

This study aims to design and implement a novel tilt integral sliding mode controller and observer for sensorless speed control of a permanent magnet synchronous motor (PMSM).

Design/methodology/approach

A control strategy combining the tilt integral derivative (TID) with sliding mode control (SMC) is proposed to determine the tilt integral sliding mode manifold. Using this manifold, tilt integral sliding mode controller (TISMC) and observer (TISMO) are designed. The stabilities are verified by using Lyapunov method. To prove the effectiveness and robustness of proposed methods, sensorless speed control of PMSM is performed for various operating conditions such as constant and variable speed references, load disturbance injection, parameter perturbation, whereas sensor noises are not taken into account. The performance of proposed method is compared with TID controller, proportional integral derivative controller and conventional SMO.

Findings

Simulation results demonstrate that TISMC and TISMO have better performance in all operating conditions. They are robust against parameter uncertainties and disturbances. TISM based sensorless control of PMSM is well guaranteed with superior performance.

Originality/value

The proposed method has not been tackled in the literature. By combining TID and SMC, novel tilt integral sliding manifold is presented and used in designing of the controller and observer. It is proven by Lyapunov method that errors converge to zero.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 6 May 2021

Darwin Silalahi, Fiz Firmanzah, Irwan Adi Ekaputra, Riani Rachmawati and Manerep Pasaribu

This paper examines the motivational influence of individuals’ team identification (TID) on their ambidexterity (TA), prosocial impact (TPS), and task performance (TTP) at the…

Abstract

Purpose

This paper examines the motivational influence of individuals’ team identification (TID) on their ambidexterity (TA), prosocial impact (TPS), and task performance (TTP) at the team level of analysis, as well as investigates the role of TA in mediating TID’s relationship with both TTP and TPS.

Design/methodology/approach

By using a cross-sectional sample of 102 cross-functional teams with a total of 362 individual members from 22 firms in the customer-facing industries of Indonesia, we analyzed multilevel data and tested hypotheses using aggregated team-level structural equation modeling (SEM).

Findings

This study supports a significant positive relationship between TID and TA. Further, while TA fully mediates the relationship between TID and TTP, TID has a direct influence on TPS.

Practical implications

This study contributes to filling the gaps in empirical evidence pertaining to the role of identity in motivating employees beyond their formal employment contracts. Their immediate leaders play a crucial role in individuals’ daily work lives and affect how they view their social identifications with their team, which subsequently contributes toward the enhancement of people and organizational performances.

Originality/value

Our study offers empirical evidence in support of the identity-enhanced principal-agent model and contributes to the literature on Social Identity Theory with a focus on the individual-group interface. To our knowledge, our study is the first empirical research on the influence of TID on TA, TPT, and TPS across multiple firms in the customer-facing industries.

Details

Journal of Organizational Effectiveness: People and Performance, vol. 8 no. 3
Type: Research Article
ISSN: 2051-6614

Keywords

Article
Publication date: 16 February 2021

Himanshukumar R. Patel, Sejal K. Raval and Vipul A. Shah

The purpose of this article is about the design of controllers for conical two-tank noninteracting level (CTTNL) system in simulation. Local linearization around the equilibrium…

Abstract

Purpose

The purpose of this article is about the design of controllers for conical two-tank noninteracting level (CTTNL) system in simulation. Local linearization around the equilibrium point has been done for the nonlinear CTTNL system to obtain a linearized model transfer function.

Design/methodology/approach

This article deals with the design of novel optimal fractional-order tilt-integral-derivative (TID) controller using type-1 fuzzy set for the CTTNL prototype system. In this study, type-1 fuzzy TID controller parameters have been optimized through genetic algorithm (GA) and those set of values have been employed for the design of proportional-integral-derivative (PID) controller.

Findings

A performance comparison between FTID and PID controller is then investigated. The analysis shows the superiority of FTID controller over PID controller in terms of integral absolute error (IAE), integral square error (ISE), integral of time multiplied absolute error (ITAE) and integral of time multiplied squared error (ITSE) integral errors. The transient and steady state performance of the FTID controller are superior as compared to conventional PID controller. In future, the FTID controller fault-tolerance capability tested on CTTNL system subject to actuator and system component (leak) faults. The detailed study of robustness in presence of model uncertainties will be incorporated as a scope of further research.

Originality/value

A performance comparison between FTID and PID controller is then investigated. The analysis shows the superiority of FTID controller over PID controller in terms of IAE, ISE, ITAE and ITSE integral errors. Additionally, fault-tolerant performance of the proposed controller evaluated with fault-recovery time (Frt) parameter. The transient and steady state performance of the FTID controller are superior as compared to conventional PID controller.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 14 no. 1
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 25 November 2020

Sonali Dohale, Kara M. Bombach, Cyril T. Brennan, Renée A. Latour and Axel S. Urie

The article examines the sweeping changes to the review process undertaken by Committee on Foreign Investment in the United States (CFIUS) as a result of the Foreign Investment…

296

Abstract

Purpose

The article examines the sweeping changes to the review process undertaken by Committee on Foreign Investment in the United States (CFIUS) as a result of the Foreign Investment Risk Review Modernization Act of 2018 (FIRRMA). The Article specifically reviews the long-awaited final sets of regulations, effective as of February 13, 2020, and analyzes their impact on the CFIUS process, as well as considers the implications of FIRRMA for parties to foreign acquisition, control, and investment transactions.

Design/methodology/approach

The Article begins with an overview of the CFIUS framework and a general explanation of FIRRMA. It then moves to an analysis of FIRRMA and the resulting changes to the prior CFIUS regime. The Article concludes with general considerations and provides recommendations for parties who may find themselves analyzing the potential applicability of CFIUS to foreign acquisition and investment transactions.

Findings

FIRRMA resulted in significant changes to the existing CFIUS regulatory framework.

Practical implications

Parties should learn the CFIUS changes as a result of FIRRMA, including the new mandatory filing requirements as well as implications for non-controlling investment transactions. Parties should include CFIUS analysis and planning in the earliest stages of deal planning and due diligence.

Originality/value

The article provides an in-depth review of the changes to CFIUS resulting from FIRRMA. The changes to the existing CFIUS landscape have resulted in new mandatory filing requirements and expanded jurisdiction over non-controlling investment and real estate transactions, which are discussed in the article.

Article
Publication date: 13 February 2019

Syahrim Azhan Ibrahim and Eiki Yamaguchi

This study aims to predict the types of thermally induced dynamics (TID) that can occur on deployable solar panels of a small form factor satellite, CubeSat which flies in low…

Abstract

Purpose

This study aims to predict the types of thermally induced dynamics (TID) that can occur on deployable solar panels of a small form factor satellite, CubeSat which flies in low Earth orbit (LEO). The TID effect on the CubeSat body is examined.

Design/methodology/approach

A 3U CubeSat with four short-edge deployable solar panels is considered. Time historic temperature of the solar panels throughout the orbit is obtained using a thermal analysis software. The results are used in numerical simulation to find the structural response of the solar panel. Subsequently, the effect of solar panel motion on pointing the direction of the satellite is examined using inertia relief method.

Findings

The thermal snap motion could occur during eclipse transitions due to rapid temperature changes in solar panels’ cross-sections. In the case of asymmetric solar panel configuration, noticeable displacement in the pointing direction can be observed during the eclipse transitions.

Research limitations/implications

This work only examines an LEO mission where the solar cells of the solar panels point to the Sun throughout the daylight period and point to the Earth while in shadow. Simplification is made to the CubeSat structure and some parameters in the space environment.

Practical implications

The results from this work reveal several practical applications worthy of simplifying the study of TID on satellite appendages.

Originality/value

This work presents a computational method that fully uses finite element software to analyze TID phenomenon that can occur in LEO on a CubeSat which has commonly used deployable solar panels structure.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 31 December 2006

Haiying Zhou, Kun Mean Hou and Christophe De Vaulx

Traditional embedded operation systems are resource consuming multitask, thus they are not adapted for smart wireless sensors. This paper presents a super‐small distributed…

Abstract

Traditional embedded operation systems are resource consuming multitask, thus they are not adapted for smart wireless sensors. This paper presents a super‐small distributed real‐time microkernel (SDREAM) dedicated to wireless sensors. SDREAM is a tuple‐based message‐driven real‐time kernel. It adopts a meta language: Kernel Modeling Language to define and describe the system primitives in abstract manner. The IPC and processes synchronization are based on the LINDA concept: the tuple model implemented by two light primitives (SND: OUT & RCV: IN). In SDREAM, tasks are classified into two categories: periodic and priority. The periodic task has the highest priority level and is responsible for capturing sensor signals or actuating control signals; the priority task has various priority levels and is suitable for time‐constraints applications. A two‐level task scheduling policy scheme, named priority‐based pre‐emptive scheduling, is used for task scheduling. SDREAM is simple and efficient. It has a flexible hardware abstraction capability that enables it to be rapidly ported into different WSN platforms and other tiny embedded devices. Currently, it has been ported and evaluated in several hardware platforms. The performance results show SDREAM requires tiny resource and is suitable and efficient for hard real‐time multitask WSN applications.

Details

International Journal of Pervasive Computing and Communications, vol. 2 no. 4
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 1 April 1976

Roberta A. Scull

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973 (Pierian…

Abstract

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973 (Pierian Press). Due to the Government Printing Office backlog during 1974, many 1973 and 1974 titles are included in this 1975 Supplement, which should have appeared earlier.

Details

Reference Services Review, vol. 4 no. 4
Type: Research Article
ISSN: 0090-7324

Book part
Publication date: 6 August 2020

Terry Eddy, Sarah Gee and Lamar Reams

Purpose: The purpose of the study was to gain insight into fans' perceptions, attitudes and behavioural responses toward their favourite college football team in the context of a…

Abstract

Purpose: The purpose of the study was to gain insight into fans' perceptions, attitudes and behavioural responses toward their favourite college football team in the context of a new beer sponsorship agreement. Specifically, the chapter examines differences in fans' attitudes and behaviours based on their gender, team identification and drinking habits.

Design/methodology/approach: A quantitative, cross-sectional survey design was employed. The sample was comprised of Amazon Mechanical Turk (MTurk) workers who self-identified as college football fans. A hypothetical scenario was used as a manipulation, whereby participants were asked to imagine their favourite college football team had entered into a new alcohol sponsorship agreement while completing a questionnaire.

Findings: Highly identified fans exhibited more positive attitudes and behaviours after being presented with the hypothetical scenario than less identified fans. In terms of gender, female fans had increased attitudes toward sponsorship compared to males, and highly identified females had the most positive attitudes and behavioural intentions toward their favourite teams of any of the four subgroups in the study.

Research limitations/implications: The small sample sizes of some fan subgroups affected statistical power, which may have led to falsely insignificant findings. The range of favourite teams among the participants (50 universities) meant there was likely a high degree of variation between fans' previous experiences with beer/alcohol at college sport venues.

Originality/value: The study offers valuable insight into the intersection of sport fandom and gender in the context of alcohol sponsorship in US college sport, and is also among the first investigations of the effects of team identification on perceptions toward alcohol sponsorship.

Details

Sport, Alcohol and Social Inquiry
Type: Book
ISBN: 978-1-78769-842-0

Keywords

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