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The purpose of this study is to provide the description of a computational methodology to model the combined propulsive systems of hydrogen propelled air-breathing scramjet vehicles and to evaluate the pollutant and climate-changing emissions.

Emissions indexes of nitrogen oxide (EINO) and water vapour released by the air turbo rocket (ATR) and dual mode ramjet (DMR) engines of the STRATOFLY air-breathing, hypersonic scramjet vehicle, propelled by hydrogen/air were evaluated. ATR engine operation was assessed for several cruise conditions in both subsonic and supersonic flight regimes in Ecosimpro software, which is an object-oriented thermodynamic design and simulation platform. ATR combustor inlet flow conditions play a key role in the computation of species mass fractions, and these conditions are highly dependent on turbomachinery performance and engine flight regime. A propulsive operational database was created by varying mass flow rates of fuel and flight conditions such as cruise speed and altitude to investigate possible engine operations. The all-inlet conditions in this map are provided to the Cantera-Python chemical/combustion chemistry solver implementing a specially designed and formulated 0D kinetic-thermodynamic methodology successfully used to model and simulate the electric spark ignition required to activate the combustion process of the reacting mixture in the ATR combustion chambers, whereas the coupled aero-thermodynamic/aero-propulsive 0D/1D code i.e. Scramjet PREliminary Aerothermodynamic Design (SPREAD), designed and developed by the Italian Aerospace Research Centre (CIRA) was used for DMR calculations. Results show low emissions of NO according to the optimized design of the ATR; on the other hand, a tuning of operational conditions is needed for DMR, with its complete re-design to be more conclusive. Analogously, the released amount of water vapour is in good agreement with the required combustion efficiency and the expected propulsive performance.

Results show low emissions of NO according to the optimized design of the ATRs; on the other hand, a tuning of operational conditions is needed for DMR, with its complete re-design to be more conclusive. Analogously, the released amount of water vapour is in good agreement with the required combustion efficiency and the expected propulsive performance.

Applications of innovative 0D/1D chemical kinetic methodology and in-house codes.

Sustaining business performance in an ever changing economic and technical environment is a challenge to be addressed with relevant management implements. This goal can be achieved by using business modelling by processes allowing for costing deliverables, controlling operations and designing information sytems aligned with business procedures and organisation. It has to be stressed that the same process model can fulfill the three purposes above mentioned so that coherent views are secured for the various business stakeholders. In addition, adequate descriptions of business processes can “scavenge” the features of business assets such as organisation, personnel qualification, information systems to be taken into account in strategic decisions.

The purpose of this paper is to critically examine existing models for cost of quality. Having identified issues and limitations of historic models, develop and implement a novel, structured hybrid cost of quality model to identify and effectively manage cost of company’s product.

A theoretical framework is proposed based on an integration of three existing, historical cost of quality models into a structured hybrid model. Subsequently, an exploratory pilot case study in a manufacturing environment is described that illustrates the value of the model.

The paper manages to find how a hybrid model can help identify cost of quality more accurately than the traditional models. Thanks to the new model, the author shows how gaps between product’s theoretical and actual costs can be highlighted. This allows management to drive down cost of quality and improve business performance.

The model would benefit from a company-wide implementation. The present study provides a starting point for further research in the international manufacturing sector.

The framework improves the knowledge of cost of quality by providing a new case study with full results and analysis from a UK-based manufacturing company. It provides a critical re-evaluation of available literature, including the most recent publications as far as practically possible within timescale available. The study shows the importance of comprehensive cost collection if companies are to have the right data needed to manage business excellence.

The paper presents a development of the first structured hybrid model for measuring cost of quality using the strongest points of main three approaches and addresses their limitations. It gives new arguments against allocation of some cost elements within BS 6143-2:1990, resulting in recommendations for further brainstorming of pros and cons of the suggestion.

The purpose of this paper is to analyze the effect of the relationship between stakeholder demand, resources, knowledge and product uniqueness on green marketing and its implication on sustainability performance.

This study used a quantitative research approach that explains the phenomenon by collecting numerical data analyzed using mathematically based methods. The research location was Batik Lawean Center of Surakarta, which is the centers of Batik industry and heritage. These locations were chosen because Laweyan and Kedung Baruk have a vision as the center of Batik industry and environment-friendly heritage through sustainable development.

Stakeholder demand, resource, knowledge and the uniqueness of the product have a significant effect on the application of green management, and the green management has a significant effect on the sustainability performance. It means that the stakeholder demand, resources, knowledge and product uniqueness have a significant effect on green management, and green management simultaneously shows a significant effect on sustainability performance. The application of green management will also improve sustainability performance.

The originality of this study is on the testing of simultaneous relationships between the factors making up the application of green marketing, namely stakeholder demand, resources, knowledge and product uniqueness, as well as the impact of green marketing implementation on sustainability performance. This study focuses on the application of green management by involving the measurement of environmental performance and financial performance, as has been investigated by Karagiorgos (2010) and Earnhart and Lizal (2006). On the other hand, this study attempts to review the application of green management in the form of environmental performance as studied by Filbeck and Gorman (2004) and Sarah and Peter (2000), which reveal several determinants of environmental performance, as suggested by Mutamimah and Handoko (2011). However, this study focuses on the qualitative determinants that have been found by researchers (Raharjo, 2016) that the low or high level of green management application is determined by the demand of stakeholders, resources, knowledge, and product uniqueness considering the object of research is the Batik industry, which is certainly different from other industries, such as those that have been investigated by Karagiorgos (2010), Earnhart and Lizal (2006), Mutamimah and Handoko (2011), Filbeck and Gorman (2004), and Sarah and Peter (2000). This study also combines the measurement of financial performance and non-financial performance in the form of sustainability performance variables.

The purpose of this study is to investigate the physical, chemical and thermal characteristics of paraffin-blended fuels to determine their suitability as fuel in hybrid rockets.

Wax fuels are viable and efficient alternatives to conventional rocket fuels, having excellent structural strength and thermal and mechanical properties. The authors report a study of the morphological, chemical and thermal properties of paraffin wax with and without additives for use as fuels in hybrid rockets. Scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy were used for the morphological and chemical characterizations of the fuel blends. The thermal stability and combustion characteristics were assessed under an atmosphere of nitrogen by the simultaneous application of thermogravimetry and differential scanning calorimetry techniques.

The melting temperatures for pure paraffin and other formulations were around 61°C as seen in differential scanning calorimetry experiments. Variations in the compositions of monoesters, n-alkanes, fatty acids, carboxylic acids methyl and hydroxyl esters in the fuel samples were assessed using Fourier transform infrared spectroscopy. The assessment criterion was chosen as the relative content of carbonyl groups, and the ratio of the stretching vibration of the C–C bonds to the deformation vibration of the aliphatic carbon–hydrogen bonds was taken as the basis for the quantitative calibration. The crystal phases identified by X-ray diffraction were used to identify nonlinear chemicals and alkane lengths. Scanning electron microscopy validated homogeneity in the paraffin-blended samples.

This study presents the thermal stability and other relevant characteristics of fuel formulations comprising unconventional blends.

This paper aims to suggest feasible solutions to overcome the problem of unmanned aerial vehicles integration within the existing airspace.

It envisages innovative time-based separation procedures that will enhance the integration in the future air traffic management (ATM) system of next generation of large remotely piloted aircraft system (RPAS). 4D navigation and dynamic mobile area concepts, both proposed in the framework of Single European Sky ATM Research program, are brought together to hypothesize innovative time-based separation procedures aiming at promoting integration of RPAS in the future ATM system.

Benefits of proposed procedures, mainly evaluated in terms of volume reduction of segregated airspace, are quantitatively analyzed on the basis of realistic operational scenarios focusing on monitoring activities in both nominal and emergency conditions. Eventually, the major limits of time-based separation for RPAS are investigated.

The implementation of the envisaged procedures will be a key enabler in RPAS integration in future ATM integration.

In the current ATM scenario, separation of RPAS from air traffic is ensured by segregating a large amount of airspace areas with fixed dimensions, dramatically limiting the activities of these vehicles.

The purpose of this paper is to provide an overview of the computational progress in the development of hydrogen-fired gas turbines. This review aims to identify suitable combustion models, appropriate NO_x chemistry mechanisms and NO_x emission levels for effective utilization of hydrogen as an alternative fuel in gas turbines.

Hydrogen is recognized as a potential alternative fuel for achieving exceptionally low emissions in gas turbines. The developments in conventional, trapped vortex combustor and micromix combustors are discussed, along with various computational models aimed at accurately predicting combustion and emission characteristics. The results of numerical simulations were then discussed with emphasis on their role in optimizing the combustor geometry.

Computational studies that were used to optimize the combustor geometry to reduce NO_x emissions and the flashback phenomenon are discussed. To retrofit existing gas turbines for hydrogen fuel, minor modifications that are required were discussed by analyzing extensive literature. The influence of key design and geometrical parameters on NO_x emissions and the appropriate selection of combustion models for numerical simulations in optimizing various combustion systems are elaborated.

The review emphasizes the computational studies in the progress of hydrogen-fired gas turbine developments. The previous reviews were primarily focused on the combustion technologies for hydrogen-fired gas turbines. This comprehensive review focuses on the key design parameters, flame structure, selection of combustion models, combustion efficiency improvement and impact of parametric studies on NO_x formation of various combustion systems, in particular hydrogen combustion for gas turbine applications.

Using the remarkable olfaction ability, insects can sense trace amounts of host plant volatiles that are notorious for causing severe damage to fruits and vegetables and in consequence the industry. The purpose of the paper is to investigate the interactions between olfactory proteins, odorant-binding proteins (OBPs) and host plant volatiles through the developed olfactory biosensors. It might be helpful to develop novel pest control strategies.

Using the successfully expressed and purified OBPs of the oriental fruit fly Bactrocera dorsalis, a biosensor was developed by immobilizing the proteins on interdigitated electrodes through nitrocellulose membrane. Based on electrochemical impedance sensing, benzaldehyde emitted by the host plants, such as Beta vulgaris, was detected, which could be used to investigate and analyze the mechanisms of pests’ sense of chemical signals. The relative decreases of charge transfer resistances of the sensor were proportional to the odorant concentrations from 10⁻⁷ M to 10⁻³ M. Meanwhile, the interactions between OBPs and benzaldehyde were studied through the process of molecular docking.

The paper provides a pest OBPs-based biosensor that could sensitively detect the host odorants benzaldehyde. Meanwhile, the most related amino acids of OBPs that bind to host plant volatiles can be distinguished with molecular docking.

An olfactory biosensor was developed to explore interactions and mechanism between the pest OBPs and benzaldehyde, which showed promising potentials for small organic molecule sensing. Simultaneously, it might be helpful for novel pest control strategies.