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Open Access
Article
Publication date: 14 November 2023

Leiting Zhao, Kan Liu, Donghui Liu and Zheming Jin

This study aims to improve the availability of regenerative braking for urban metro vehicles by introducing a sensorless operational temperature estimation method for the braking…

Abstract

Purpose

This study aims to improve the availability of regenerative braking for urban metro vehicles by introducing a sensorless operational temperature estimation method for the braking resistor (BR) onboard the vehicle, which overcomes the vulnerability of having conventional temperature sensor.

Design/methodology/approach

In this study, the energy model based sensorless estimation method is developed. By analyzing the structure and the convection dissipation process of the BR onboard the vehicle, the energy-based operational temperature model of the BR and its cooling domain is established. By adopting Newton's law of cooling and the law of conservation of energy, the energy and temperature dynamic of the BR can be stated. To minimize the use of all kinds of sensors (including both thermal and electrical), a novel regenerative braking power calculation method is proposed, which involves only the voltage of DC traction network and the duty cycle of the chopping circuit; both of them are available for the traction control unit (TCU) of the vehicle. By utilizing a real-time iterative calculation and updating the parameter of the energy model, the operational temperature of the BR can be obtained and monitored in a sensorless manner.

Findings

In this study, a sensorless estimation/monitoring method of the operational temperature of BR is proposed. The results show that it is possible to utilize the existing electrical sensors that is mandatory for the traction unit’s operation to estimate the operational temperature of BR, instead of adding dedicated thermal sensors. The results also validate the effectiveness of the proposal is acceptable for the engineering practical.

Originality/value

The proposal of this study provides novel concepts for the sensorless operational temperature monitoring of BR onboard rolling stocks. The proposed method only involves quasi-global electrical variable and the internal control signal within the TCU.

Open Access
Article
Publication date: 13 September 2023

Siyao Li, Bo Yuan, Yun Bai and Jianfeng Liu

To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following…

Abstract

Purpose

To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure, energy-saving performance of the whole metro system cannot be guaranteed.

Design/methodology/approach

A cooperative train control framework is formulated to regulate a novel train operation mode. The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train. An improved brute force (BF) algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.

Findings

Case studies on the actual metro line in Guangzhou, China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters. The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.

Originality/value

Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process, which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation. This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea, where energy-efficient train operation can be realised once train running time is determined, thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.

Details

Railway Sciences, vol. 2 no. 3
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 12 December 2023

Christine T. Domegan, Tina Flaherty, John McNamara, David Murphy, Jonathan Derham, Mark McCorry, Suzanne Nally, Maurice Eakin, Dmitry Brychkov, Rebecca Doyle, Arthur Devine, Eva Greene, Joseph McKenna, Finola OMahony and Tadgh O'Mahony

To combat climate change, protect biodiversity, maintain water quality, facilitate a just transition for workers and engage citizens and communities, a diversity of stakeholders…

Abstract

Purpose

To combat climate change, protect biodiversity, maintain water quality, facilitate a just transition for workers and engage citizens and communities, a diversity of stakeholders across multiple levels work together and collaborate to co-create mutually beneficial solutions. This paper aims to illustrate how a 7.5-year collaboration between local communities, researchers, academics, companies, state agencies and policymakers is contributing to the reframing of industrial harvested peatlands to regenerative ecosystems and carbon sinks with impacts on ecological, economic, social and cultural systems.

Design/methodology/approach

The European Union LIFE Integrated Project, Peatlands and People, responding to Ireland’s Climate Action Plan, represents Europe’s largest rehabilitation of industrially harvested peatlands. It makes extensive use of marketing research for reframing strategies and actions by partners, collaborators and communities in the evolving context of a just transition to a carbon-neutral future.

Findings

The results highlight the ecological, economic, social and cultural reframing of peatlands from fossil fuel and waste lands to regenerative ecosystems bursting with biodiversity and climate solution opportunities. Reframing impacts requires muddling through the ebbs and flows of planned, possible and unanticipated change that can deliver benefits for peatlands and people over time.

Research limitations/implications

At 3 of 7.5 years into a project, the authors are muddling through how ecological reframing impacts economic and social/cultural reframing. Further impacts, planned and unplanned, can be expected.

Practical implications

This paper shows how an impact planning canvas tool and impact taxonomy can be applied for social and systems change. The tools can be used throughout a project to understand, respond to and manage for unplanned events. There is constant learning, constantly going back to the impact planning canvas and checking where we are, what is needed. There is action and reaction to each other and to the diversity of stakeholders affected and being affected by the reframing work.

Originality/value

This paper considers how systemic change through ecological, economic, social and cultural reframing is a perfectly imperfect process of muddling through which holds the promise of environmental, economic, technological, political, social and educational impacts to benefit nature, individuals, communities, organisations and society.

Details

European Journal of Marketing, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0309-0566

Keywords

Open Access
Article
Publication date: 28 February 2019

Steffen Lehmann

Climate change is occurring around us and impacting on our daily lives, meaning that we have to deal with our cities in a different way. There is also increasing awareness of the…

Abstract

Climate change is occurring around us and impacting on our daily lives, meaning that we have to deal with our cities in a different way. There is also increasing awareness of the need for daily contact with green spaces and the natural environment in order to live a happy, productive and meaningful life.

This reflective essay tells the narrative of how urbanisation has been disconnecting humans from nature. Non-sustainable, non-resilient patterns of urbanisation, along with the neglect of inner-city areas, have resulted in fragmentation and urban decline, led to a loss of biodiversity, and caused the deterioration of ecosystems and their services. Urban regeneration projects allow us to “repair” and restore some of this damage whilst enhancing urban resilience. Connecting existing and enhanced ecosystems, and re-establishing ecosystems both within cities and at the peri-urban fringe is vital for strengthening ecosystem resilience and building adaptive capacity for coping with the effects of climate change.

Cities worldwide need to look for suitable solutions to increase the resilience of their urban spaces in the face of climate change. This essay explores how this can be achieved through the integration of nature-based solutions, the re-greening of neighbourhoods and by correctly attributing value to natural capital. Transforming existing cities and neighbourhoods in this way will enable ecosystems to contribute their services towards healthier and more liveable cities.

Details

Emerald Open Research, vol. 1 no. 5
Type: Research Article
ISSN: 2631-3952

Keywords

Open Access
Book part
Publication date: 2 October 2023

Saad Ghauri

This qualitative study explores how multinational enterprises (MNEs) approach sustainable innovation through the lens of innovation theory and doughnut economics. The study…

Abstract

This qualitative study explores how multinational enterprises (MNEs) approach sustainable innovation through the lens of innovation theory and doughnut economics. The study proposes a conceptual framework to evaluate the practices of businesses and the findings illustrate how sustainable innovation occurs within two MNEs. Based on interviews with professionals of two Swedish MNEs, responsible for sustainability, the study examines how sustainable innovations lead to the redesign of core business pillars and transforms the operating market for the MNE. Overall, this study makes a theoretical contribution by formulating an application of Raworth’s (2017) doughnut model to business strategy. It also provides practical insight into the dynamics of sustainable innovation, which aims to inform and inspire further progress in sustainable development by businesses and academia.

Details

Creating a Sustainable Competitive Position: Ethical Challenges for International Firms
Type: Book
ISBN: 978-1-80455-252-0

Keywords

Open Access
Article
Publication date: 10 July 2019

Hoyon Hwang, Jaeyoung Cha and Jon Ahn

The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft…

3711

Abstract

Purpose

The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft design framework provides a simple method to design solar aircraft for users of all levels of experience.

Design/methodology/approach

This design framework consists of algorithms and user interfaces for the design of experiments, optimization and mission analysis that includes aerodynamics, performance, solar energy, weight and flight distances.

Findings

The proposed sizing method produces the optimal solar aircraft that yields the minimum weight and satisfies the constraints such as the power balance, the night time energy balance and the lift coefficient limit.

Research limitations/implications

The design conditions for the sizing process are given in terms of mission altitudes, flight dates, flight latitudes/longitudes and design factors for the aircraft configuration.

Practical implications

The framework environment is light and easily accessible as it is implemented using open programs without the use of any expensive commercial tools or in-house programs. In addition, this study presents a sizing method for solar aircraft as traditional sizing methods fail to reflect their unique features.

Social implications

Solar aircraft can be used in place of a satellite and introduce many advantages. The solar aircraft is much cheaper than the conventional satellite, which costs approximately $200-300m. It operates at a closer altitude to the ground and allows for a better visual inspection. It also provides greater flexibility of missions and covers a wider range of applications.

Originality/value

This study presents the implementation of a function that yields optimized flight performance under the given mission conditions, such as climb, cruise and descent for a solar aircraft.

Details

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

Keywords

Open Access
Article
Publication date: 4 March 2020

Marco Fioriti, Silvio Vaschetto, Sabrina Corpino and Giovanna Premoli

This paper aims to present the main results achieved in the frame of the TIVANO national-funded project which may anticipate, in a stepped approach, the evolution and the design…

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Abstract

Purpose

This paper aims to present the main results achieved in the frame of the TIVANO national-funded project which may anticipate, in a stepped approach, the evolution and the design of the enabling technologies needed for a hybrid/electric medium altitude long endurance (MALE) unmanned aerial vehicle (UAV) to perform persistent intelligence surveillance reconnaissance (ISR) military operations.

Design/methodology/approach

Different architectures of hybrid-propulsion system are analyzed pointing out their operating modes to select the more suitable architecture for the reference aircraft. The selected architecture is further analyzed together with its electric power plant branch focusing on electric system architecture and the selected electric machine. A final comparison between the hybrid and standard propulsion is given at aircraft level.

Findings

The use of hybrid propulsion may lead to a reduction of the total aircraft mass and an increase in safety level. However, this result comes together with a reduced performance in climb phase.

Practical implications

This study can be used as a reference for similar studies and it provides a detailed description of propulsion operating modes, power management, electric system and machine architecture.

Originality/value

This study presents a novel application of hybrid propulsion focusing on a three tons class MALE UAV for ISR missions. It provides new operating modes of the propulsion system and a detailed electric architecture of its powertrain branch and machine. Some considerations on noise emissions and infra-red traceability of this propulsion, at aircraft level.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 5
Type: Research Article
ISSN: 1748-8842

Keywords

Open Access
Article
Publication date: 13 May 2022

Sue Ogilvy, Danny O'Brien, Rachel Lawrence and Mark Gardner

This paper aims to demonstrate methods that sustainability-conscious brands can use to include their primary producers in the measurement and reporting of the environment and…

2052

Abstract

Purpose

This paper aims to demonstrate methods that sustainability-conscious brands can use to include their primary producers in the measurement and reporting of the environment and sustainability performance of their supply chains. It explores three questions: How can farm businesses provide information required in sustainability reporting? What are the challenges and opportunities experienced in preparing and presenting the information? What future research and policy instruments might be needed to resolve these issues.

Design/methodology/approach

This study identifies and describes methods to provide the farm-level information needed for environmental performance and sustainability reporting frameworks. It demonstrates them by compiling natural capital accounts and environmental performance information for two wool producers in the grassy woodland biome of Eastern Australia; the contrasting history and management of these producers would be expected to result in different environmental performances.

Findings

The authors demonstrated an approach to NC accounting that is suitable for including primary producers in environmental performance reporting of supply chains and that can communicate whether individual producers are sustaining, improving or degrading their NC. Measurements suitable for informing farm management and for the estimation of supply chain performance can simultaneously produce information useful for aggregation to regional and national assessments.

Practical implications

The methods used should assist sustainability-conscious supply chains to more accurately assess the environmental performance of their primary producers and to use these assessments in selective sourcing strategies to improve supply chain performance. Empirical measures of environmental performance and natural capital have the potential to enable evaluation of the effectiveness of sustainability accounting frameworks in inducing businesses to reduce their environmental impacts and improve the condition of the natural capital they depend on.

Social implications

Two significant social implications exist for the inclusion of primary producers in the sustainability and environmental performance reporting of supply chains. Firstly, it presently takes considerable time and expense for producers to prepare this information. Governments and members of the supply chain should acknowledge the value of this information to their organisations and consider sharing some of the cost of its preparation with primary producers. Secondly, the “additionality” requirement commonly present in existing frameworks may perversely exclude already high-performing producers from being recognised. The methods proposed in this paper provide a way to resolve this.

Originality/value

To the best of the authors’ knowledge, this research is the first to describe detailed methods of collecting data for natural capital accounting and environmental performance reporting for individual farms and the first to compile the information and present it in a manner coherent with the Kering EP&L and the UN SEEA EA. The authors believe that this will make a significant contribution to the development of fair and standardised ways of measuring individual farm performance and the performance of food, beverage and apparel supply chains.

Details

Sustainability Accounting, Management and Policy Journal, vol. 13 no. 4
Type: Research Article
ISSN: 2040-8021

Keywords

Open Access
Article
Publication date: 31 December 2010

Min-Jung Kim, Seock-Jin Hong and Hun-Koo Ha

This study estimated greenhouse gas emissions from aviation transportation and sought systems that could manage these emissions based on the IPCC guidelines to prepare for…

Abstract

This study estimated greenhouse gas emissions from aviation transportation and sought systems that could manage these emissions based on the IPCC guidelines to prepare for greenhouse gas regulations on international airlines. For this purpose, policies to reduce greenhouse gas emissions from aviation transportation were developed based on international agreements and the cases of advanced countries. In addition, marginal abatement costs and greenhouse gas reduction measures were derived for the effective execution of these policies. While estimating greenhouse gas emissions from aviation transportation, it was found that there has been an average increase of 3.9% and 12.9% for domestic and international flights, indicating that it is urgent that we prepare global greenhouse gas regulations. The estimated marginal abatement cost of greenhouse gas from airplanes was approximately. USD 123, and this amount could be used to decide the price of emission rights, the amount of carbon tax, and could be referred to when distributing incentives for voluntary agreements.

The measures to reduce greenhouse gas emissions for aviation transportation were classified into four types: voluntary agreements, international collaboration, greenhouse gas reduction technology and operation process development, and application of emission trading and carbon tax.

Details

Journal of International Logistics and Trade, vol. 8 no. 2
Type: Research Article
ISSN: 1738-2122

Keywords

Open Access
Article
Publication date: 13 April 2017

Nora Munguia, Alejandra Varela, Javier Esquexr and Luis Eduardo Velázquez Contreras

At the 21st Conference of the Parties to the United Nations Convention on Climate Change (COP 21) in Paris, 195 governments reached an agreement pivotal not only for countries but…

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Abstract

Purpose

At the 21st Conference of the Parties to the United Nations Convention on Climate Change (COP 21) in Paris, 195 governments reached an agreement pivotal not only for countries but also for companies. The Paris Agreement makes it impossible to practice business as usual. The transition to a low-carbon coffee industry could be achieved by fostering corporate sustainability. Accordingly, the purpose of this paper is to provide empirical evidence of how to adopt the principles of Paris Agreement by enhancing the corporate sustainability of a Mexican coffee-roaster company using the inventory phase of the life cycle assessment tool.

Design/methodology/approach

The data collection process followed the requirements of the International Reference Life Cycle Data System Handbook, developed by the Institute for Environment and Sustainability in the European Commission Joint Research Centre, and data on packaging materials and energy production were drawn from a commercially available database in the LCA software SimaPro.

Findings

Compiling data on the energy of the firm’s material flows in a firm revealed opportunities to improve energy efficiency and to reduce greenhouse gas emissions. The results of the inventory analysis can be used to evaluate the specific environmental impacts of the coffee-roasting process at this Mexican coffee company. Data compilation activities for energy flows identified the need to install liquefied petroleum gas measuring devices and individual measuring devices for electricity consumption in different areas of the coffee plant. It is recommended that, while implementing this option, the company also develop an energy management program to achieve energy efficiency.

Practical implications

The inventory data in this case study permit comparisons of the current state of the system studied and its possible future states and offer stakeholders relevant information on resource use. Similarly, the project results provide the basis for future research on environmental performance in the coffee industry in Mexico and for the development of policies regarding the production process in the coffee supply chain. Consequently, this research can help fulfil Mexico’s commitment to the Paris Agreement.

Social implications

Reaching the goal of the Paris Agreement will require gathering key information for each single company. The current case study has provided key data to foster the principles of sustainability in the Mexican coffee industry to help this sector to transit toward sustainable development, which is a new demand of the Mexican society. Even though it may seem simple, this is the hardest step for enhancing stakeholder involvement in corporate sustainability.

Originality/value

The main contribution of this research to science and practice is to confirm that fostering corporate sustainability is easier and more feasible when energy flow information is available.

Details

PSU Research Review, vol. 1 no. 1
Type: Research Article
ISSN: 2399-1747

Keywords

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