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1 – 10 of 192Ibrahim Neya, Daniel Yamegueu, Adamah Messan, Yezouma Coulibaly, Arnaud Louis Sountong-Noma Ouedraogo and Yawovi Mawuénya Xolali Dany Ayite
The stabilization of earthen blocks improves their mechanical strength and avoids adobe construction erosion due to rainwater. However, the stabilization affects the thermal…
Abstract
Purpose
The stabilization of earthen blocks improves their mechanical strength and avoids adobe construction erosion due to rainwater. However, the stabilization affects the thermal properties of the earthen blocks, and thus their capacity to provide adequate thermal comfort to occupants. This article examines the influence of cement and geopolymer binders on thermal comfort in compressed earthen buildings in hot and arid climates.
Design/methodology/approach
The test cell is on the building platform in Burkina Faso. The building is made of compressed earth blocks (CEB) consisting of laterite, water and binder. The thermal models of the building were implemented in EnergyPlus v9.0.1 software. Empirical validation is used to check whether the model used for the thermal dynamic simulation can reproduce with accuracy the thermal behavior in a real situation. The adaptive thermal comfort model of ASHRAE 55–2010 was used to assess thermal comfort in long-term hot and dry tropical conditions.
Findings
The results show that the CEB buildings remain hot despite the use of cement or geopolymer binder. Indeed, with both cement and geopolymer binders, on a daily basis, 19 h and 15 h are uncomfortable during, respectively, the hot and cold seasons. An increase of 1% in cement content raises the comfort hours by 9.2 h during the hot season and 11.7 h during the cold season. Hence, the comfort time varies linearly with the cement content in the building material. Moreover, there is no linear relationship between comfort time and geopolymer rate.
Research limitations/implications
Complementary work should also assess the influence of stabilization on building humidity levels. In fact, earthen materials are very sensitive to outdoor humidity and indoor humidity affects thermal comfort even if it is not taken into account in the ASHRAE adaptive thermal comfort model.
Practical implications
The present study will certainly contribute to a better valorization of clay potential in countries with similar climatic conditions.
Social implications
The use of geopolymer binder is a suitable ecological option to replace the cement binder. It is important to mention that nighttime comfort can be increased through passive strategies such as natural ventilation.
Originality/value
Most CEB material stabilization analyses including cement and geopolymer ones were mostly investigated at the laboratory scale and less at the building scale. Also, the influence of the binder rate on the thermal performance of buildings made of cement and geopolymer has not yet been assessed. This paper fills this gap of knowledge by assessing the impact of cement and geopolymer binder rates on the thermal comfort of CEB dwellings.
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Uche Emmanuel Edike, Olumide Afolarin Adenuga, Daniel Uwumarogie Idusuyi and Abdulkabir Adedamola Oke
The purpose of this study is to advance the application of pulverised cow bone ash (PCBA) as a partial replacement of cement in soil stabilisation for the production of bricks…
Abstract
Purpose
The purpose of this study is to advance the application of pulverised cow bone ash (PCBA) as a partial replacement of cement in soil stabilisation for the production of bricks. The study investigated the impact of PCBA substitution on the characteristic strength of clay bricks under variant curing media.
Design/methodology/approach
Dried cow bones were pulverised, and an energy-dispersive X-ray fluorescence test was conducted on PCBA samples to determine the chemical constituents and ascertain the pozzolanic characteristics. Ordinary Portland cement (OPC) and PCBA were blended at 100%, 75%, 50%, 25% and 0% of cement substitution by mass to stabilise lateritic clay at 10% total binder content for the production of bricks. The binder-to-lateritic clay matrixes were used to produce clay bricks and cylinders for compressive and splitting tensile strength tests, respectively.
Findings
The study found that PCBA and OPC have similar chemical compositions. The strength of the clay bricks increased with curing age, and the thermal curing of clay bricks positively impacted the strength development. The study established that PCBA is a suitable substitute for cement, up to 25% for stabilisation in clay brick production.
Practical implications
Construction stakeholders can successfully use a PCBA-OPC binder blend of 1:3 to stabilise clay at 10% total binder content for the production of bricks. The stabilised clay bricks should be cured at an elevated temperature of approximately 90°C for 48 h to achieve satisfactory performance.
Originality/value
The PCBA-OPC binder blend provides adequate soil stabilisation for the production of clay bricks and curing the clay bricks at elevated temperature. This aspect of the biomass/OPC binder blend has not been explored for brick production, and this is important for the reduction of the environmental impacts of cement production and waste from abattoirs.
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Mika Luhtala, Olga Welinder and Elina Vikstedt
This study aims to investigate the adoption of the United Nations’ Sustainable Development Goals (SDGs) as the new performance perspective in cities. It also aims to understand…
Abstract
Purpose
This study aims to investigate the adoption of the United Nations’ Sustainable Development Goals (SDGs) as the new performance perspective in cities. It also aims to understand how accounting for SDGs begins in city administrations by following Power’s (2015) fourfold development schema composed of policy object formation, object elaboration, activity orchestration and practice stabilization.
Design/methodology/approach
Focusing on a network of cities coordinated by the Finnish local government association, we analyzed the six largest cities in Finland employing a holistic multiple case study strategy. Our data consisted of Voluntary Local Reviews (VLRs), city strategies, budget plans, financial statements, as well as results of participant observations and semi-structured interviews with key individuals involved in accounting for SDGs.
Findings
We unveiled the SDG framework as an interpretive scheme through which cities glocalized sustainable development as a novel, simultaneously global and local, performance object. Integration of the new accounts in city management is necessary for these accounts to take life in steering the actions. By creating meaningful alignment and the ability to impact managerial practices, SDGs and VLRs have the potential to influence local actions. Our results indicate further institutionalization progress of sustainability as a performance object through SDG-focused work.
Originality/value
While prior research has focused mainly on general factors influencing the integration of the sustainability agenda, this study provides a novel perspective by capturing the process and demonstrating empirically how new accounts on SDGs are introduced and deployed in the strategic planning and management of local governments.
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Guilherme de Araujo Grigoli, Maurilio Ferreira Da Silva Júnior and Diego Pereira Pedra
This study aims to identify the main challenges to achieving humanitarian logistics in the context of United Nations peace missions in sub-Saharan Africa and to present…
Abstract
Purpose
This study aims to identify the main challenges to achieving humanitarian logistics in the context of United Nations peace missions in sub-Saharan Africa and to present suggestions for overcoming the logistical gaps encountered.
Design/methodology/approach
The methodological approach of the work focuses on the comparative case study of the United Nations Mission in South Sudan, the United Nations Multidimensional Integrated Stabilisation Mission in the Central African Republic and The United Nations Organisation Stabilisation Mission in the Democratic Republic of Congo from 2014 to 2021. The approach combined a systematic literature review with the authors’ empirical experience as participant observers in each mission, combining theory and practice.
Findings
As a result, six common challenges were identified for carrying out humanitarian logistics in the three peace missions. Each challenge revealed a logistical gap for which an appropriate solution was suggested based on the best practices found in the case study of each mission.
Research limitations/implications
This paper presents limitations when addressing the logistical analysis based on only three countries under the UN mission as a case study, as well as conceiving that certain flaws in the system, in the observed period, are already in the process of correction with the adoption of the 2016–2021 strategy by the UN Global Logistic Cluster. The authors suggest that further studies can be carried out by expanding the number of cases or using countries where other bodies (AU, NATO or EU) work.
Originality/value
To the best of the authors’ knowledge, this study is the first comparative case study of humanitarian logistics on the three principal missions of the UN conducted by academics and practitioners.
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Thuy Thanh Tran, Roger Leonard Burritt, Christian Herzig and Katherine Leanne Christ
Of critical concern to the world is the need to reduce consumption and waste of natural resources. This study provides a multi-level exploration of the ways situational and…
Abstract
Purpose
Of critical concern to the world is the need to reduce consumption and waste of natural resources. This study provides a multi-level exploration of the ways situational and transformational links between levels and challenges are related to the adoption and utilization of material flow cost accounting in Vietnam, to encourage green productivity.
Design/methodology/approach
Based on triangulation of public documents at different institutional levels and a set of semi-structured interviews, situational and transformational links and challenges for material flow cost accounting in Vietnam are examined using purposive and snowball sampling of key actors.
Findings
Using a multi-level framework the research identifies six situational and transformational barriers to implementation of material flow cost accounting and suggests opportunities to overcome these. The weakest links identified involve macro-to meso-situational and micro-to macro-transformational links. The paper highlights the dominance of meso-level institutions and lack of focus on micro transformation to cut waste and enable improvements in green productivity.
Practical implications
The paper identifies ways for companies in Vietnam to reduce unsustainability and enable transformation towards sustainable management and waste reduction.
Originality/value
The paper is the first to develop and use a multi-level/multi-time period framework to examine the take-up of material flow cost accounting to encourage transformation towards green productivity. Consideration of the Vietnamese case builds understanding of the challenges for achieving United Nations Sustainable Development Goal number 12, to help enable sustainable production and consumption patterns.
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Оleksandra Kohut, Nataliia Tokareva and Olha Poliakovska
The purpose of this study is to determine the psychological features of providing initial psychotherapeutic assistance to victims, in particular to military servants.
Abstract
Purpose
The purpose of this study is to determine the psychological features of providing initial psychotherapeutic assistance to victims, in particular to military servants.
Design/methodology/approach
Theoretical analysis of scientific works; observation of servicemen in hospital conditions; conversations with servicemen and doctors; and interviews with foreign colleagues.
Findings
As a result of theoretical and empirical research, it was found that initial psychological assistance is more effective if it is provided in a timely and comprehensive manner in cooperation with medical assistance, if the recommended exercises are performed systematically by the victim and if a certain algorithm for providing initial psychotherapeutic assistance is used.
Originality/value
The authors present their own algorithm for providing initial psychological assistance to military servants: psychophysiological stabilization; adjustment of emotional balance; restoration of cognitive processes and acquisition of constructive coping strategies; and formation of life meanings that provide an opportunity to survive the crisis period of life. In this paper, the authors also note the importance of providing psychological first aid to victims of extreme situations in a timely manner, which helps reduce the intensity of symptoms of acute stress disorder and reduces the likelihood of post-traumatic stress disorder.
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Gopinath Anjinappa and Divakar Bangalore Prabhakar
The fluctuations that occurred between the power requirements have shown a higher range of voltage regulations and frequency. The fluctuations are caused because of substantial…
Abstract
Purpose
The fluctuations that occurred between the power requirements have shown a higher range of voltage regulations and frequency. The fluctuations are caused because of substantial changes in the energy dissipation. The operational efficiency has been reduced when the power grid is enabled with the help of electric vehicles (EVs) that were created by the power resources. The model showed an active load matching for regulating the power and there occurred a harmonic motion in energy. The main purpose of the proposed research is to handle the energy sources for stabilization which has increased the reliability and improved the power efficiency. This study or paper aims to elaborate the security and privacy challenges present in the vehicle 2 grid (V2G) network and their impact with grid resilience.
Design/methodology/approach
The smart framework is proposed which works based on Internet of Things and edge computations that managed to perform an effective V2G operation. Thus, an optimum model for scheduling the charge is designed on each EV to maximize the number of users and selecting the best EV using the proposed ant colony optimization (ACO). At the first, the constructive phase of ACO where the ants in the colony generate the feasible solutions. The constructive phase with local search generates an ACO algorithm that uses the heterogeneous colony of ants and finds effectively the best-known solutions widely to overcome the problem.
Findings
The results obtained by the existing in-circuit serial programming-plug-in electric vehicles model in terms of power usage ranged from 0.94 to 0.96 kWh which was lower when compared to the proposed ACO that showed power usage of 0.995 to 0.939 kWh, respectively, with time. The results showed that the energy aware routed with ACO provided feasible routing solutions for the source node that provided the sensor network at its lifetime and security at the time of authentication.
Originality/value
The proposed ACO is aware of energy routing protocol that has been analyzed and compared with the energy utilization with respect to the sensor area network which uses power resources effectively.
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Chao Lu and Xiaohai Xin
The promotion of autonomous vehicles introduces privacy and security risks, underscoring the pressing need for responsible innovation implementation. To more effectively address…
Abstract
Purpose
The promotion of autonomous vehicles introduces privacy and security risks, underscoring the pressing need for responsible innovation implementation. To more effectively address the societal risks posed by autonomous vehicles, considering collaborative engagement of key stakeholders is essential. This study aims to provide insights into the governance of potential privacy and security issues in the innovation of autonomous driving technology by analyzing the micro-level decision-making processes of various stakeholders.
Design/methodology/approach
For this study, the authors use a nuanced approach, integrating key stakeholder theory, perceived value theory and prospect theory. The study constructs a model based on evolutionary game for the privacy and security governance mechanism of autonomous vehicles, involving enterprises, governments and consumers.
Findings
The governance of privacy and security in autonomous driving technology is influenced by key stakeholders’ decision-making behaviors and pivotal factors such as perceived value factors. The study finds that the governmental is influenced to a lesser extent by the decisions of other stakeholders, and factors such as risk preference coefficient, which contribute to perceived value, have a more significant influence than appearance factors like participation costs.
Research limitations/implications
This study lacks an investigation into the risk sensitivity of various stakeholders in different scenarios.
Originality/value
The study delineates the roles and behaviors of key stakeholders and contributes valuable insights toward addressing pertinent risk concerns within the governance of autonomous vehicles. Through the study, the practical application of Responsible Innovation theory has been enriched, addressing the shortcomings in the analysis of micro-level processes within the framework of evolutionary game.
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Francesco Busato, Maria Ferrara and Monica Varlese
This paper analyzes real and welfare effects of a permanent change in inflation rate, focusing on macroprudential policy’ role and its interaction with monetary policy.
Abstract
Purpose
This paper analyzes real and welfare effects of a permanent change in inflation rate, focusing on macroprudential policy’ role and its interaction with monetary policy.
Design/methodology/approach
While investigating disinflation costs, the authors simulate a medium-scale dynamic general equilibrium model with borrowing constraints, credit frictions and macroprudential authority.
Findings
Providing discussions on different policy scenarios in a context where still it is expected high inflation, there are three key contributions. First, when macroprudential authority actively operates to improve financial stability, losses caused by disinflation are limited. Second, a Taylor rule directly responding to financial variables might entail a trade-off between price and financial stability objectives, by increasing disinflation costs. Third, disinflation is welfare improving for savers, while costly for borrowers and banks. Indeed, while savers benefit from policies reducing price stickiness distortion, borrowers are worried about credit frictions, coming from collateral constraint.
Practical implications
The paper suggests threefold policy implications: the macroprudential authority should actively intervene during a disinflation process to minimize costs and financial instability deriving from it; policymakers should implement a disinflationary policy stabilizing also output; the central bank and the macroprudential regulator should pursue financial and price stability goals, separately.
Originality/value
This paper is the first attempt to study effects of a permanent inflation target reduction in focusing on the macroprudential policy’ role.
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Mahesh Gaikwad, Suvir Singh, N. Gopalakrishnan, Pradeep Bhargava and Ajay Chourasia
This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the…
Abstract
Purpose
This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the non-dimensional capacity parameters for the axial and flexural load-carrying capacity of reinforced concrete (RC) sections for heating and the subsequent post-heating phase (decay phase) of the fire.
Design/methodology/approach
The sectional analysis method is used to determine the moment and axial capacities. The findings of sectional analysis and heat transfer for the heating stage are initially validated, and the analysis subsequently proceeds to determine the load capacity during the fire’s heating and decay phases by appropriately incorporating non-dimensional sectional and material parameters. The numerical analysis includes four fire curves with different cooling rates and steel percentages.
Findings
The study’s findings indicate that the rate at which the cooling process occurs after undergoing heating substantially impacts the axial and flexural capacity. The maximum degradation in axial and flexural capacity occurred in the range of 15–20% for cooling rates of 3 °C/min and 5 °C/min as compared to the capacity obtained at 120 min of heating for all steel percentages. As the fire cooling rate reduced to 1 °C/min, the highest deterioration in axial and flexural capacity reached 48–50% and 42–46%, respectively, in the post-heating stage.
Research limitations/implications
The established non-dimensional parameters for axial and flexural capacity are limited to the analysed section in the study owing to the thermal profile, however, this can be modified depending on the section geometry and fire scenario.
Practical implications
The study primarily focusses on the degradation of axial and flexural capacity at various time intervals during the entire fire exposure, including heating and cooling. The findings obtained showed that following the completion of the fire’s heating phase, the structural capacity continued to decrease over the subsequent post-heating period. It is recommended that structural members' fire resistance designs encompass both the heating and cooling phases of a fire. Since the capacity degradation varies with fire duration, the conventional method is inadequate to design the load capacity for appropriate fire safety. Therefore, it is essential to adopt a performance-based approach while designing structural elements' capacity for the desired fire resistance rating. The proposed technique of using non-dimensional parameters will effectively support predicting the load capacity for required fire resistance.
Originality/value
The fire-resistant requirements for reinforced concrete structures are generally established based on standard fire exposure conditions, which account for the fire growth phase. However, it is important to note that concrete structures can experience internal damage over time during the decay phase of fires, which can be quantitatively determined using the proposed non-dimensional parameter approach.
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