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This study aims to find the characteristics of supercritical airfoil in helicopter rotor blades for hovering phase using numerical analysis and the validation using experimental results.

Using numerical analysis in the forward phase of the helicopter, supercritical airfoil is compared with the conventional airfoil for the aerodynamic performance. The multiple reference frame method is used to produce the results for rotational analysis. A grid independence test was carried out, and validation was obtained using benchmark values from NASA data.

From the analysis results, a supercritical airfoil in hovering flight analysis proved that the NASA SC rotor produces 25% at 5°, 26% at 12° and 32% better thrust at 8° of collective pitch than the HH02 rotor. Helicopter performance parameters are also calculated based on momentum theory. Theoretical calculations prove that the NASA SC rotor is better than the HH02 rotor. The results of helicopter performance prove that the NASA SC rotor provides better aerodynamic efficiency than the HH02 rotor.

The novelty of the paper is it proved the aerodynamic performance of supercritical airfoil is performing better than the HH02 airfoil. The results are validated with the experimental values and theoretical calculations from the momentum theory.

Reducing aircraft fuel consumption has become a paramount research area, focusing on optimizing operational parameters like speed and altitude during the cruise phase. However, the existing methods for fuel reduction often rely on complex experimental calculations and data extraction from embedded systems, making practical implementation challenging. To address this, this study aims to devise a simple and accessible approach using available information.

In this paper, a novel analytic method to estimate and optimize fuel consumption for aircraft equipped with jet engines is proposed, with a particular emphasis on speed and altitude parameters. The dynamic variations in weight caused by fuel consumption during flight are also accounted for. The derived fuel consumption equation was rigorously validated by applying it to the Boeing 737–700 and comparing the results against the fuel consumption reference tables provided in the Boeing manual. Remarkably, the equation yielded closely aligned outcomes across various altitudes studied. In the second part of this paper, a pioneering approach is introduced by leveraging the particle swarm optimization algorithm (PSO). This novel application of PSO allows us to explore the equation’s potential in finding the optimal altitude and speed for an actual flight from Algiers to Brussels.

The results demonstrate that using the main findings of this study, including the innovative equation and the application of PSO, significantly simplifies and expedites the process of determining the ideal parameters, showcasing the practical applicability of the approach.

The suggested methodology stands out for its simplicity and practicality, particularly when compared to alternative approaches, owing to the ready availability of data for utilization. Nevertheless, its applicability is limited in scenarios where zero wind effects are a prevailing factor.

The research opens up new possibilities for fuel-efficient aviation, with a particular focus on the development of a unique fuel consumption equation and the pioneering use of the PSO algorithm for optimizing flight parameters. This study’s accessible approach can pave the way for more environmentally conscious and economical flight operations.

This study aims to examine the effect of human resource management (HRM) in mitigating negative effects of Lean management and Six Sigma (LM&SS) on employee well-being in health care. The authors subdivide well-being into three components: happiness, trust and health.

This is a cross-sectional, multisite survey study in internal service units of hospitals. Data analyzed using multivariate regression come from a sample of 1,886 survey respondents (42 units, N = 218 supervisors, N = 1,668 employees) in eight Dutch academic hospitals that have implemented LM&SS.

The present study findings show no or weak effects of LM&SS on the happiness and health component of employee well-being. In addition, the authors found a significant but weak direct positive effect (ß = 0.07) of the LM&SS bundle on the trusting relationships component of well-being. Therefore, moderating effects of HRM practices on the relationship between LM&SS and employee well-being seem less relevant because an existing relationship between LM&SS and employee well-being is a prerequisite for moderation (Hayes, 2009). There were unexpected side effects. Inspired by research that discusses direct effects of HRM on employee well-being, the authors tested this relationship and found that HRM has a direct positive effect on trust and happiness of employees in health care. For the health component of well-being, the present results show a weak negative effect of HRM.

This study results in a cautiously optimistic view about LM&SS in health care, provided that it is applied in a targeted manner (to improve the performance of their processes) and that HRM is strategically aligned with the goals of LM&SS to improve employees’ happiness and trusting relationships.

Unique features of the study are the focus on the consequences for employees’ well-being related to LM&SS in health care, the role of HRM in regard to this relationship and the participation of all eight Dutch academic hospitals in this research.

The purpose of this paper was to systematically study the electrical properties of 5‐, 42‐ and 75‐nm gap polysilicon structures to evaluate the potentiality of these structures to be used in biomolecular sensing devices.

The authors previously reported the fabrication and morphological characterization of these structures. In this report, they electrically probed the presence of nanogap through current measurement. The effects of electrolytes on the capacitance profiles of these structures were systematically studied with air, water and various dilutions of phosphate buffer saline.

An increment in capacitance was found with the increment in electrolyte concentration. Improvement in current flow, capacitance, permittivity, and conductivity were observed with the smaller size nanogaps, suggesting their applications in low power consuming devices.

Since nanogap‐based dielectric biosensing devices need to be operated with a low level of current to avoid biomolecular damage, these structures should have potential applications in dielectric‐based biomolecular detection using a low cost dielectric analyser.

The sandy environment is one of the typical environments in which helicopters operate. Air-sand two-phase flow in sandy environments may be an important factor affecting flight safety. Taking a typical example, this paper aims to investigate the aerodynamic and rotor trim characteristics of the UH-60 helicopter in sandy environments.

A computational study is conducted to simulate the air-sand flow over airfoils based on the Euler–Lagrange framework. The simulation uses the S-A turbulence model and the two-way momentum coupling methodology. Additionally, the trim characteristics of the UH-60 rotor are calculated based on the isolated rotor trim algorithm.

The simulation results show that air-sand flow significantly affects the aerodynamic characteristics of the SC1095 airfoil and the SC1094R8 airfoil. The presence of sand particles leads to a decrease in lift and an increase in drag. The calculation results of the UH-60 helicopter rotor indicate that the thrust decreases and the torque increases in the sandy environment. To maintain a steady forward flight in sandy environments, it is necessary to increase the collective pitch and the longitudinal cyclic pitch.

In this paper, the aerodynamic characteristics of airfoils and the trim characteristics in the air-sand flow of the UH-60 helicopter are discussed, which might be a new view to analyse the impact of sandy environments on helicopter safety and manoeuvring.

Process improvement initiatives, such as Lean, Six Sigma and Lean Six Sigma, typically have common characteristics that are carried through projects. Whilst a project’s performance is an important determinant of the successful implementation of continuous improvement (CI) initiatives, its failure can undermine the impact of any CI initiative on business performance. As a result, an understanding of the reasons of process improvement project failures is crucial. The purpose of this paper is to present the results of a pilot survey highlighting the most common reasons for process improvement project failures.

This paper presents a pilot survey of 42 Brazilian manufacturing specialists who have been involved in process improvement projects. The participants of this survey were Six Sigma Master Black Belts, Black Belts, Green Belts and Six Sigma champions from manufacturing companies in Brazil. The survey questionnaire was piloted with five experts in the field in order to ensure that the questions were valid and technically sound.

The execution of Six Sigma projects in organizations results in a moderate rate of project failures. These failures can cost organizations several millions of dollars especially within the context of larger organizations. The main reasons for project failure, as cited by the specialists include: resistance to change, lack of commitment and support from top management and incompetent teams.

The authors report the findings from a pilot survey having a limited sample size. Moreover, the data have been collected from one country and primarily from large manufacturing companies.

To the best of the authors’ knowledge, this is the first empirical study looking into the reasons for process improvement project failures. The authors argue that if the top reasons for such failures are understood, a framework can be developed in the future that can mitigate the chance of project failures during project execution. This could potentially lead to significant savings to the bottom-line of many organizations.

This study aims to illustrate an overarching picture of the knowledge base on change management, including contributing authors, institutions and countries. The study also aims to elicit the intellectual structure of the knowledge base using science mapping.

The authors engaged 1,457 published documents, generated from a SCOPUS search, to analyse research conducted in the area of change management. Bibliometric indicators such as authors, institutions and countries were used in the analysis. Additionally, science mapping analyses such as keyword co-occurrence and co-citation were also performed using VOSviewer.

The findings indicated that scholarly work in the field of change management is on the rise. Furthermore, while the contribution from different regions of the world was observed, the most impactful scholarly works came from the West and Asia. Finally, it was found that research on change management could be classified into four schools of thought; engineering and information and communication technology (ICT) industry, organisational aspects of change, leadership aspects of change and human aspects of change.

This study contributes to the knowledge base on change management by creating an intellectual landscape of the existing research. The results demonstrated that the existing literature on the topic forms four broad clusters of knowledge and that the ICT industry is the current epicentre of research in this area. These findings could benefit researchers, as well as practitioners in streamlining their actions towards the most relevant and critical areas on the topic of change management.

The case describes how Radio Mirchi dealt with competition in the Bangalore FM radio market. Radio Mirchi's market share in Bangalore started declining within a few months of its successful launch, following the entry of new competitors in the market. The case discusses strategies adopted by the company to regain its market share and become the market leader. It describes the initial product offering of the channel, why it felt the need to redesign its product mix, and eventually how the company changed its product offering. The focus of the case is on the dilemma faced by the organization while shifting to a new product and service design in the face of emerging competition. The case highlights the importance of continuously monitoring the market environment and developing a keen understanding of the consumers' behaviour for an organization to gain and sustain its leadership position in the marketplace.

This study aims to undertake a review of how carbon trading contributes to a reduction in emission of greenhouse gases (CHGs).

A narrative literature review approach was adopted to identify and synthesise existing literature using the Scopus and Web of Science databases. Articles were limited to the past 10 years to obtain the most current literature. The various ways in which carbon trading leads to reductions in emissions were identified and discussed.

The results showed that the main ways in which carbon trading contributes to reductions in emissions are through innovation in low-carbon technologies, restoration of ecosystems through offset money, development of renewable and clean energy and providing information on investment related to emissions.

The value of this study is to contribute to the built environment’s climate change mitigation agenda by identifying the role of carbon trading.

The output of this research identifies and contextualises the role carbon trading plays in the reduction of CHG emissions.

The design of robot hand for writing and correction assistant applications work will be partially replaced as to develop the remote-assisted robot hand control needed to manipulate all this kind of work. As it is stress and strain full job for all teachers, which needs to bring a sustainable solution, hence robot hand which resembles the human hand which is teleoperated with the remote control is designed.

This work presents the design and simulation of a robot hand for correction assistant applications. To replace the work partially especially for the teachers who are undergoing the paper correction work like putting tick mark, cross mark, allocation of marks, etc.

In this paper the design of the same and its simulation of writing the horizontal line, vertical line and writing number two is presented, in further research, a prototype model and its analysis will be done.

The design is been done using the modelling software Creo 5.4 where the design will be used to print the prototype model which is physical using 3D printing technology and controlling and testing will be done on the same prototype model using simple Arduino.