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1 – 10 of 190Ibrahim 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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Kirsten Russell, Fiona Barnett, Sharon Varela, Simon Rosenbaum and Robert Stanton
The mental and physical health of those residing in Australian rural and remote communities is poorer compared to major cities. Physical health comorbidities contribute to almost…
Abstract
Purpose
The mental and physical health of those residing in Australian rural and remote communities is poorer compared to major cities. Physical health comorbidities contribute to almost 80% of premature mortality for people living with mental illness. Leisure time physical activity (LTPA) is a well-established intervention to improve physical and mental health. To address the physical and mental health of rural and remote communities through LTPA, the community’s level of readiness should be first determined. This study aims to use the community readiness model (CRM) to explore community readiness in a remote Australian community to address mental health through LTPA.
Design/methodology/approach
Individual semi-structured interviews were conducted using the CRM on LTPA to address mental health. Quantitative outcomes scored the community’s stage of readiness for LTPA programmes to address mental health using the CRM categories of one (no awareness) to nine (high level of community ownership). Qualitative outcomes were thematically analysed, guided by Braun and Clark.
Findings
The community scored six (initiation) for community efforts and knowledge of LTPA programmes and seven (stabilisation) for leadership. The community’s attitude towards LTPA and resources for programmes scored four (pre-planning), and knowledge of LTPA scored three (vague awareness).
Originality/value
To the best of the authors’ knowledge, this is the first Australian study to use CRM to examine community readiness to use LTPA to improve mental health in a remote community. The CRM was shown to be a useful tool to identify factors for intervention design that might optimise community empowerment in using LTPA to improve mental health at the community level.
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Jinhuan Tang, Qiong Wu and Kun Wang
Intelligent new energy vehicles (INEVs) are becoming the competitive hotspot for the automobile industry. The major purpose of this study is to determine how to increase…
Abstract
Purpose
Intelligent new energy vehicles (INEVs) are becoming the competitive hotspot for the automobile industry. The major purpose of this study is to determine how to increase innovation efficiency through knowledge sharing and technology spill between new energy vehicle (NEV) enterprises and technology enterprises. This will help to improve the core competence of the automobile industry in China. Also, it serves as a guide for the growth of other strategic.
Design/methodology/approach
The authors construct a tripartite evolutionary game model to study the cross-border cooperative innovation problem. Firstly, the payment matrix of NEV enterprise, technology enterprise and government is established, and the expected revenue of each participant is determined. Then, the replication dynamic equations and evolutionary stability strategies are analyzed. Finally, the theoretical research is validated through numerical simulation.
Findings
Results showed that: (1) An optimal range of revenue distribution coefficient exists in the cross-border cooperation. (2) Factors like research and development (R&D) success rate, subsidies, resource and technology complementarity, and vehicles intelligence positively influence the evolution towards cooperative strategies. (3) Factors like technology spillover risk cost inhibit the evolution towards cooperative strategies. To be specific, when the technology spillover risk cost is greater than 2.5, two enterprises are inclined to choose independent R&D, and the government chooses to provide subsidy.
Research limitations/implications
The research perspective and theoretical analysis are helpful to further explore the cross-border cooperation of the intelligent automobile industry. The findings suggest that the government can optimize the subsidy policy according to the R&D capability and resource allocation of automobile industry. Moreover, measures are needed to reduce the risk of technology spillovers to encourage enterprise to collaborate and innovate. The results can provide reference for enterprises’ strategic choice and government’s policy making.
Originality/value
The INEV industry has become an important development direction of the global automobile industry. However, there is limited research on cross-border cooperation of INEV industry. Hence, authors construct a tripartite evolutionary game model involving NEV enterprise, technology enterprise and the government, and explore the relationship of cooperation and competition among players in the INEV industry, which provides a new perspective for the development of the INEV industry.
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Xingyu Qu, Zhenyang Li, Qilong Chen, Chengkun Peng and Qinghe Wang
In response to the severe lag in tracking the response of the Stewart stability platform after adding overload, as well as the impact of nonlinear factors such as load and…
Abstract
Purpose
In response to the severe lag in tracking the response of the Stewart stability platform after adding overload, as well as the impact of nonlinear factors such as load and friction on stability accuracy, a new error attenuation function and a parallel stable platform active disturbance rejection control (ADRC) strategy combining cascade extended state observer (ESO) are proposed.
Design/methodology/approach
First, through kinematic modeling of the Stewart platform, the relationship between the desired pose and the control quantities of the six hydraulic cylinders is obtained. Then, a linear nonlinear disturbance observer was established to observe noise and load, to enhance the system’s anti-interference ability. Finally, verification was conducted through simulation.
Findings
Finally, stability analysis was conducted on the cascaded observer. Experiments were carried out on a parallel stable platform with six degrees of freedom involving rotation and translation. In comparison to traditional PID and ADRC control methods, the proposed control strategy not only endows the stable platform with strong antiload disturbance capability but also exhibits faster response speed and higher stability accuracy.
Originality/value
A new error attenuation function is designed to address the lack of smoothness at d in the error attenuation function of the ADRC controller, reducing the system ripple caused by it. Finally, a combination of linear and nonlinear ESOs is introduced to enhance the system's response speed and its ability to observe noise and load disturbances. Stability analysis of the cascade observer is carried out, and experiments are conducted on a six-degree-of-freedom parallel stable platform with both rotational and translational motion.
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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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