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The purpose of this paper is to propose a new approach for aerodynamic parameter identification of hypersonic vehicles, which is based on Pigeon-inspired optimization (PIO) algorithm, with the objective of overcoming the disadvantages of traditional methods based on gradient such as New Raphson method, especially in noisy environment.

The model of hypersonic vehicles and PIO algorithm is established for aerodynamic parameter identification. Using the idea, identification problem will be converted into the optimization problem.

A new swarm optimization method, PIO algorithm is applied in this identification process. Experimental results demonstrated the robustness and effectiveness of the proposed method: it can guarantee accurate identification results in noisy environment without fussy calculation of sensitivity.

The new method developed in this paper can be easily applied to solve complex optimization problems when some traditional method is failed, and can afford the accurate hypersonic parameter for control rate design of hypersonic vehicles.

In this paper, the authors converted this identification problem into the optimization problem using the new swarm optimization method – PIO. This new approach is proved to be reasonable through simulation.

This article examines the influence of Daoist nothingness on leadership in growing Chinese small and medium enterprises (SMEs). Daoism is based on a “letting-go” approach through maintaining inherent openness, which challenges goal-oriented and hierarchical approaches typical of Western and Confucian leadership theories. This facilitates the cross-fertilization of ideas related to the effective management of smaller firms.

This study focuses on SME leaders in a group of 12 growing SMEs in the Shanghai logistics industry in China. Narrative and semi-structured interviews explored emerging aspects beyond the established model of leadership associated with reputation-building. This led to in-depth, thick descriptions, broadening our understanding of leadership and reputation-building.

SME leaders follow nothingness by continuously adopting a letting-go approach which spontaneously fosters reputation-building. By maintaining inherent openness, nothingness functions as an enabling principle that mobilizes multi-beings leading to reputation-building in unintended ways.

A greater plurality of empirical and methodological contexts in Western and non-Western countries helps to understand the dynamics and intersection of Daoist nothingness, leadership and reputation-building.

SME leaders recounted how they discursively practised nothingness for extended periods in their everyday practice. The study shows the significance of nothingness for SME leaders who aspire to grow their businesses by reputation-building among salient stakeholders.

Daoist nothingness provides insights into the distinctive approach of Chinese SME leaders and their relationships with local and distant stakeholders. By engaging in active non-action they relax pre-determined intentions and immerse themselves in the process of leading, where the connections between goals and processes are automatically animated. Such an approach differs from the top-down and goal-oriented approach to leadership adopted in many Western SMEs.

This paper makes two theoretical contributions. First, it indicates the powerful influence of Daoist nothingness on leadership by drawing on the broader context of entrepreneurship in Chinese SMEs. Secondly, it enriches existing concepts such as reputation by endowment and reputation borrowing by demonstrating how Daoist nothingness silently fosters both local reputation and generalized reputation.

This paper aims to present a new design for removable partial dentures (RPDs) for partially edentulous patients to improve the efficiency and quality of RPD manufacturing. Additive and subtractive manufacturing technologies and zirconium silicate micro-ceramic bonding in the aesthetic zone are used herein.

A case was presented. First, RPD digital definitive casts were acquired, and then digital frameworks with crown retainers and digital crowns were obtained by computer-aided design (CAD). The titanium alloy frameworks and resin crowns were fabricated by three-dimensional (3D) printing and computer-aided manufacturing (CAM) processes, respectively. The crowns adhered to the crown retainers. Ceramage bonding was used to reform the gingival anatomy in the aesthetic zone during the fabrication of the RPDs. The finished RPDs were assessed by a clinician and delivered to the patient.

The RPDs were conventionally assessed by a clinician, were deemed to be accurate and satisfied both the patient and clinician.

This novel method provides a way to fabricate RPDs with a combination of additive and subtractive manufacturing technologies. The design of the framework was different from that of a conventional framework because it contained the crown retainers, and the traditional base retainer no longer existed. Ceramage bonding was used to replicate the gingival anatomy in the aesthetic zone. The new RPDs provided accuracy and were less time-consuming to produce than those produced with the traditional method. The new method enables the digital manufacturing of nearly the entire RPDs.

The purpose of this paper is to prepare Ti(C,N) coatings on TA15 treated and not treated by shot peening using double glow plasma alloying technique. The effect of shot peening on the wear behavior of Ti(C,N) coatings is discussed.

The Ti(C,N) coatings were prepared by double glow plasma alloying technique on two different TA15 substrate; one is shot peened and the other is not.

Ti(C,N) coating on SP-treated TA15 was thicker and denser, and the grain size was smaller compared with that on original TA15. Compared with the Ti(C,N) coating on original TA15, the wear resistance of that on SP-treated TA15 is improved. Ti(C,N) coating on SP-treated TA15 showed higher nanohardness and bearing capacity than that on original TA15.

For double glow plasma alloying technique, surface quality, surface activity and other factors will have influence on the thickness and density of the coating. The wear mechanisms of Ti(C,N) coating on original TA15 are serious abrasive wear and oxidation wear. However, the wear mechanism of Ti(C,N) coating on SP-treated TA15 is slightly oxidation wear.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0283/

This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.

A thiazole Schiff bases were synthesized, named, 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A), which was fabricated respectively on copper surface by the molecular self-assembled. Evaluation was carried out by electrochemical measurement and surface analysis techniques. Measurement of static friction coefficient scanning electron microscopy and Contact angle analysis were applied, and it is finally confirmed the existence of the adsorbed film. The inhibitive mechanism of A was evaluated by means of quantitative calculation and molecular dynamics simulation.

The electrochemical measurement indicated that the self-assembled molecular film can effectively inhibit the corrosion of copper sheet, when the concentration was 15 mmol⋅L⁻¹ and the assembly time was 6 h, the corrosion inhibition effect was the best, reaching as high as 97.5 per cent. Scanning electron microscopy results showed that the Schiff base compound forms a protective film on the surface of the copper, which effectively blocks the transfer of corrosion particles to the metal substrate, thereby inhibiting the occurrence of corrosion. Adsorption behavior of A followed the Langmuir’s adsorption isotherm and attributed to mixed-type adsorption. The results of Quantitative calculation and molecular dynamics simulation showed that A was adsorbed on Cu (111) surface in parallel.

In this study, the corrosion inhibition properties of Schiff base film were investigated by combining theory with experiment. Theoretical calculation is helpful to guide the synthesis of efficient and environmentally friendly corrosion inhibitors.

The damage caused by metal corrosion is great. The self-assembled Schiff base membrane synthesized in this paper is simple and compact, and the corrosion inhibition efficiency of copper in 3 per cent NaCl solution is 97.5 per cent.

Inhibition of metal corrosion can better save energy and reduce economic losses.

The synthesized Schiff base was prepared on the copper surface by the molecular self-assembled. The Schiff base membrane has a good corrosion inhibition effect on copper in 3 per cent NaCl solution, and the corrosion inhibition efficiency is up to 97.5 per cent.

This paper aims to present a method of reproducing multi-object structures from materials of diverse physical properties with the use of models fabricated by means of rapid prototyping (RP) techniques.

A process of modelling complex anatomical structures of soft tissues and bones using mandible models as examples was described. The study is based on data acquired through standard computed tomography. Physical models of examined objects were fabricated with RP technology from a 3D-CAD virtual model.

In the analysis of complex medical issues, beside numerical methods, one can simultaneously make use of experimental tests to verify obtained results. In the case of experimental tests, it is necessary to fabricate physical models with appropriate material properties. RP techniques used in the method ensure accurate reproduction of the external shape of the fabricated model, whereas consecutive stages allow us to construct moulds and create internal structures within a finished model by wax cast models.

The application of a physical RP model makes the identification of medical problem more efficient and the reconstruction of pathological alterations for experimental tests clearer. It prevents the simplification of assumptions to experimental analysis. The approach may reduce costs of fabricating models for experimental studies and offers the possibility of using materials of desired properties.

The approach developed by the authors and presented in this paper was submitted for patent protection as “A Method of Reconstructing Medical Models with Internal Structure and the Use of Materials of Diverse properties” – patent application no. P.398644.

Rapid satellite capture by a free-floating space robot is a challenge problem because of no-fixed base and time-delay issues. This paper aims to present a modified target capturing control scheme for improving the control performance.

For handling such control problem including time delay, the modified scheme is achieved by adding a delay calibration algorithm into the visual servoing loop. To identify end-effector motions in real time, a motion predictor is developed by partly linearizing the space robot kinematics equation. By this approach, only ground-fixed robot kinematics are involved in the predicting computation excluding the complex space robot kinematics calculations. With the newly developed predictor, a delay compensator is designed to take error control into account. For determining the compensation parameters, the asymptotic stability condition of the proposed compensation algorithm is also presented.

The proposed method is conducted by a credible three-dimensional ground experimental system, and the experimental results illustrate the effectiveness of the proposed method.

Because the delayed camera signals are compensated with only ground-fixed robot kinematics, this proposed satellite capturing scheme is particularly suitable for commercial on-orbit services with cheaper on-board computers.

This paper is original as an attempt trying to compensate the time delay by taking both space robot motion predictions and compensation error control into consideration and is valuable for rapid and accurate satellite capture tasks.

This paper aims to review the knowledge management (KM) processes, knowledge conversion modes and critical success factors (CSFs) and contextualise them to the construction setting to guide effective KM implementation.

This paper is conceptual in nature. It begins with a review of issues faced by construction organisations, which led them to consider implementing KM. This is followed by a comprehensive review of KM processes, knowledge conversion modes, KM CSFs and their application to the construction industry.

Based on the socialisation, externalisation, combination and internalisation (SECI) model, the knowledge conversion modes are discussed, linking them to the KM processes of knowledge creation, sharing, storage and application. The KM CSFs identified from construction literature suggest that they can be categorised into two groups, namely, factors within organisational control (managerial influence, technological influence and resource influence) and factors beyond organisational control (social influence, political influence, environmental influence, economic influence, industry influence and construction technology influence). The resulting review is discussed in terms of how construction organisations can implement KM effectively to achieve the desired project performance outcomes in terms of time, cost and quality.

Although this paper has made some theoretical contributions, a quantitative analysis will further reinforce its value both in theory and practice, particularly in terms of applying the KM processes and CSFs to different organisational, industry and country settings. A quantitative research is being carried out in the major construction sector in Sri Lanka to establish the relationships between the KM processes, knowledge conversion modes and KM CSFs with project performance outcomes, which will be reported in a subsequent publication.

As the construction industry uses a considerable number of knowledge workers, implementing KM for project planning and execution is the key to sustaining the growth of construction organisations and industry, particularly when KM implementation is linked to project performance outcomes. Practical implications are provided in terms of what successful KM implementation entails.

Effective KM implementation can serve as a conduit for construction organisations to build capacity and develop the ability to react quickly to social challenges brought about by different stakeholders, even before the project commences, so that the project performance outcomes will not be affected. Another social implication is the role played by project team members, in which efforts have to be put in place to facilitate the use of KM processes, so that teams can align project activities to the general good of their organisations.

A comprehensive KM framework that guides the construction industry on KM implementation is long overdue. This research represents the first of such attempts to view KM from a wider perspective, both in terms of internal and external influences affecting construction organisations. Once the conceptual framework developed is validated, it is expected to bring enormous benefits to different stakeholders.

The purpose of this study is to investigate the influence of knowledge management critical success factors (KM CSFs) on project management performance outcomes in major construction organisations in Sri Lanka. As a result, the significant KM CSFs are prioritised to support KM implementation.

This study is cross-sectional in nature, adopting the quantitative method of analysis. The research model includes nine KM CSFs (culture, leadership, organisational structure, IT support, T-shaped skills, training, teamwork, performance measurement and benchmarking) and nine items measuring project management performance outcomes. Data were collected from senior, middle and technical staff involved in projects by means of a self-administered survey questionnaire mailed to them.

The Pearson’s correlation coefficient suggests that all of the KM CSFs are adequately correlated except for organisational structure, which has a poor correlation with IT support, T-shaped skills, teamwork and benchmarking. The results of multiple linear regression show that four KM CSFs (T-shaped skills, teamwork, benchmarking and transformational leadership) are significantly and positively related to project management performance outcomes. The remaining five KM CSFs are not significant. The multiple-criteria decision-making analysis reveals that benchmarking, transformational leadership, teamwork and T-shaped skills are the main priority for the construction organisations to consider in implementing KM.

Future studies should consider construction organisations of multiple sizes and include factors beyond organisational control, KM processes and the effects of demographic variables. Longitudinal studies are also imperative to determine the performance impact brought about by KM implementation over a period of time.

Benchmarking, transformational leadership, teamwork and T-shaped skills should serve as the initial focus to support KM implementation to achieve the desired project management performance outcomes. It is only after these KM CSFs are in place that the construction organisations can concentrate on other factors.

This study contributes to a better understanding of the relationships between the KM CSFs and project management performance outcomes in the construction industry in Sri Lanka, which is still at its infancy stage of KM implementation. Prioritisation of the significant KM CSFs in supporting effective KM implementation in the construction organisations further enhances the value of this study.