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1 – 10 of over 2000Natiq Yaseen Taha Al-Menahlawi, Mohammad Reza Khoshravan Azar, Tajbakhsh Navid Chakherlou and Hussein Al-Bugharbee
The purpose of this study is a numerical simulation and an analytical analysis about the low-velocity impact on a functionally graded porous plate with porosity distribution in…
Abstract
Purpose
The purpose of this study is a numerical simulation and an analytical analysis about the low-velocity impact on a functionally graded porous plate with porosity distribution in the thickness direction. In this article, polymethyl methacrylate is used for matrix, and single-walled carbon nanotube (CNTs) (10,10) with consideration agglomeration sizes and lumping of CNT inside the agglomerations is applied for reinforcement.
Design/methodology/approach
In analytical formulation, the non-linear Hertz contact law is applied for interaction between projectile and plate surface. High-order shear deformation plate theory is developed, and energy of the system for impactor and plate is written. The governing equations are derived using Ritz method and Lagrange equations and are solved using the fourth-order Runge–Kutta method. Also, ABAQUS finite element model of functionally graded porous plate with all edges simply supported and reinforced by CNT under low-velocity impact is simulated and is compared with those is achieved in the present analytical approach.
Findings
In parametric studies, the influence of porosity distribution patterns include uniform, non-uniform symmetric and non-uniform asymmetric on the histories of contact force and impactor displacement of simply supported plate reinforced by CNT are presented. Eventually, the effects of porosity coefficient, impactor initial velocity, impactor radius and CNTs lumping inside agglomerations for non-uniform symmetric distribution patterns are discussed in impact event in detail.
Originality/value
In this paper, the effect of combination of polymethyl methacrylate and CNTs with consideration agglomeration sizes and lumping of CNTs inside the agglomerations in the form of a functionally graded porous plate is studied in the problem of low-velocity impact analysis.
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Raghavendra Rao N.S. and Chitra A.
The purpose of this study is to propose an extended reliability method for an industrial motor drive by integrating the physics of failure (PoF).
Abstract
Purpose
The purpose of this study is to propose an extended reliability method for an industrial motor drive by integrating the physics of failure (PoF).
Design/methodology/approach
Industrial motor drive systems (IMDS) are currently expected to perform beyond the desired operating conditions to meet the demand. The PoF of the subsystem affects its reliability under such harsh operating circumstances. It is crucial to estimate reliability by integrating PoF, which helps in understanding its impact and to develop a fault-tolerant design, particularly in such an integrated drive system. An integrated PoF extended reliability method for industrial drive system is proposed to address this issue. In research, the numerical failure rate of each component of industrial drive is obtained first with the help of the MIL-HDBK-217 military handbook. Furthermore, the mathematically deduced proposed approach is modeled in the GoldSim Monte Carlo reliability workbench.
Findings
From the results, for a 15% rise in integrated PoF, the reliability and availability of the entire IMDS dropped by 23%, resulting in an impact on mean time to failure (MTTF).
Originality/value
The integrated PoF of the motor and motor controller affects industrial drive reliability, which falls to 0.18 with the least MTTF (2.27 years); whose overall reliability of industrial drive drops to 0.06 if it is additionally integrated with communication protocol.
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Zarjina Tarana Khalil and Samira Rahman
Although healthcare and healthy living are integral to the Sustainable Development Goals (SDGs) for 2030, the coronavirus epidemic has dealt a devastating blow to these efforts…
Abstract
Although healthcare and healthy living are integral to the Sustainable Development Goals (SDGs) for 2030, the coronavirus epidemic has dealt a devastating blow to these efforts. As governments and policymakers were compelled to shift their focus to lockdowns, sustenance, procurement, and distribution of vaccines, the momentum for health initiatives slowed, and the already fragile health systems of emerging markets were subjected to additional shocks. However, in many underserved regions of the globe, the introduction of technology has greatly facilitated the distribution and adoption of healthcare services.
This chapter highlights mini-cases from four emerging nations: Bangladesh, Nigeria, Vietnam, and the Philippines. Although the countries are emerging, each one of them are in a distinct stage of development and face a unique set of healthcare-related challenges. The chapter showcases how four different organizations based in these countries leveraged the use of technology to take healthcare services to underserved populations. In doing so, they addressed the key challenges of imparting healthcare: geographic accessibility, availability, financial accessibility, and acceptability.
This chapter concludes with a discussion of the implications of expanding healthcare industries leading to increased healthcare waste. To prevent mass population exposure to hazardous substances, the emergence of intelligent healthcare waste collection and disposal systems will be an absolute necessity. Hence, with the development of healthcare services, governments and policymakers need to mechanize smart waste management systems to safeguard humans, animals, and the environment.
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Kei Kimura, Takeshi Onogi, Naoya Yotsumoto and Fuminobu Ozaki
In this study, the effects of strain rate on the bending strength of full-scale wide-flange steel beams have been examined at elevated temperatures. Both full-scale loaded heating…
Abstract
Purpose
In this study, the effects of strain rate on the bending strength of full-scale wide-flange steel beams have been examined at elevated temperatures. Both full-scale loaded heating tests under steady-state conditions and in-plane numerical analysis using a beam element have been employed.
Design/methodology/approach
The load–deformation relationships in 385 N/mm2-class steel beam specimens was examined using steady-state tests at two loading rate values (0.05 and 1.00 kN/s) and at two constant member temperatures (600 and 700 °C). Furthermore, the stress–strain relationships considering the strain rate effects were proposed based on tensile coupon test results under various strain rate values. The in-plane elastoplastic numerical analysis was conducted considering the strain rate effect.
Findings
The experimental test results of the full-scale steel beam specimens confirmed that the bending strength increased with increase in strain rate. In addition, the analytical results agreed relatively well with the test results, and both strain and strain rate behaviours of a heated steel member, which were difficult to evaluate from the test results, could be quantified numerically.
Originality/value
The novelty of this study is the quantification of the strain rate effect on the bending strength of steel beams at elevated temperatures. The results clarify that the load–deformation relationship of steel beams could be evaluated by using in-plane analysis using the tensile coupon test results. The numerical simulation method can increase the accuracy of evaluation of the actual behaviour of steel members in case of fire.
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Theocharis Moysiadis, Konstantina Spanaki, Ayalew Kassahun, Sabine Kläser, Nicolas Becker, George Alexiou, Nikolaos Zotos and Iliada Karali
Traceability of food is of paramount importance to the increasingly sustainability-conscious consumers. Several tracking and tracing systems have been developed in the AgriFood…
Abstract
Purpose
Traceability of food is of paramount importance to the increasingly sustainability-conscious consumers. Several tracking and tracing systems have been developed in the AgriFood sector in order to prove to the consumers the origins and processing of food products. Critical challenges in realizing food's traceability include cooperating with multiple actors on common data sharing standards and data models.
Design/methodology/approach
This research applies a design science approach to showcase traceability that includes preharvest activities and conditions in a case study. The authors demonstrate how existing data sharing standards can be applied in combination with new data models suitable for capturing transparency information about plant production.
Findings
Together with existing studies on farm-to-fork transparency, our results demonstrate how to realize transparency from field to fork and enable producers to show a complete bill of sustainability.
Originality/value
The existing standards and data models address transparency challenges in AgriFood chains from the moment of harvest up to retail (farm-to-fork) relatively well, but not what happens before harvest. In order to address sustainability concerns, there is a need to collect data about production activities related to product quality and sustainability before harvesting and share it downstream the supply chain. The ability to gather data on sustainability practices such as reducing pesticide, herbicide, fertilizer and water use are crucial requirements for producers to market their produce as quality and sustainable products.
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Zeye Fu, Jiahao Zou, Luxin Han and Qi Zhang
A model for calculating the global overpressure time history of a single cloud detonation from overpressure time history of discrete positions in the range of single cloud…
Abstract
Purpose
A model for calculating the global overpressure time history of a single cloud detonation from overpressure time history of discrete positions in the range of single cloud detonation is to be proposed and verified. The overpressure distribution produced by multiple cloud detonation and the influence of cloud spacing and fuel mass of every cloud on the overpressure distribution are to be studied.
Design/methodology/approach
A calculation method is used to obtain the global overpressure field distribution after single cloud detonation from the overpressure time history of discrete distance to detonation center after single cloud detonation. On this basis, the overpressure distribution produced by multi-cloud under different cloud spacing and different fuel mass conditions is obtained.
Findings
The results show that for 150 kg fuel, when the spacing of three clouds is 40 m, 50 m, respectively, the overpressure range of larger than 0.1 MPa is 5496.48 mˆ2 and 6235.2 mˆ2, which is 2.89 times and 3.28 times of that of single cloud detonation. The superposition effect can be ignored when the spacing between the three clouds is greater than 60 m. In the case of fixed cloud spacing, once the overpressure forms continuous effective superposition, the marginal utility of fuel decreases.
Originality/value
A model for calculating the global overpressure time history of a single cloud detonation from overpressure time history of discrete positions in the range of single cloud detonation is proposed and verified. Based on this method, the global overpressure field of single cloud detonation is reconstructed, and the superimposed overpressure distribution characteristics of three cloud detonation are calculated and analyzed.
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Ying Gao, Qiang Zhang, Xiaoran Wang, Yanmei Huang, Fanshuang Meng and Wan Tao
Currently, the Tang tomb mural cultural relic resources are presented in a multi-source and heterogeneous manner, with a lack of effective organization and sharing between…
Abstract
Purpose
Currently, the Tang tomb mural cultural relic resources are presented in a multi-source and heterogeneous manner, with a lack of effective organization and sharing between resources. Therefore, this study aims to propose a multidimensional knowledge discovery solution for Tang tomb mural cultural relic resources.
Design/methodology/approach
Taking the Tang tomb murals collected by the Shaanxi History Museum as an example, based on clarifying the relevant concepts of Tang tomb mural resources and considering both dynamic and static dimensions, a top-down approach was adopted to first construct an ontology model of Tang tomb mural type cultural relics resources. Then, the actual case data was imported into the Neo4J graph database according to the defined pattern hierarchy to complete the static organization of knowledge, and presented in a multimodal form in knowledge reasoning and retrieval. In addition, geographic information system (GIS) technology is used to dynamically display the spatiotemporal distribution of Tang tomb mural resources, and the distribution trend is analysed from a digital humanistic perspective.
Findings
The multi-dimensional knowledge discovery of Tang tomb mural cultural relics resources can help establish the correlation and spatiotemporal relationship between resources, providing support for semantic retrieval and navigation, knowledge discovery and visualization and so on.
Originality/value
This study takes the murals in the collection of the Shaanxi History Museum as an example, revealing potential knowledge associations in a static and intelligent way, achieving knowledge discovery and management of Tang tomb murals, and dynamically presents the spatial distribution of Tang tomb murals through GIS technology, meeting the knowledge presentation needs of different users and opening up new ideas for the study of Tang tomb murals.
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The paper provides a detailed historical account of Douglass C. North's early intellectual contributions and analytical developments in pursuing a Grand Theory for why some…
Abstract
Purpose
The paper provides a detailed historical account of Douglass C. North's early intellectual contributions and analytical developments in pursuing a Grand Theory for why some countries are rich and others poor.
Design/methodology/approach
The author approaches the discussion using a theoretical and historical reconstruction based on published and unpublished materials.
Findings
The systematic, continuous and profound attempt to answer the Smithian social coordination problem shaped North's journey from being a young serious Marxist to becoming one of the founders of New Institutional Economics. In the process, he was converted in the early 1950s into a rigid neoclassical economist, being one of the leaders in promoting New Economic History. The success of the cliometric revolution exposed the frailties of the movement itself, namely, the limitations of neoclassical economic theory to explain economic growth and social change. Incorporating transaction costs, the institutional framework in which property rights and contracts are measured, defined and enforced assumes a prominent role in explaining economic performance.
Originality/value
In the early 1970s, North adopted a naive theory of institutions and property rights still grounded in neoclassical assumptions. Institutional and organizational analysis is modeled as a social maximizing efficient equilibrium outcome. However, the increasing tension between the neoclassical theoretical apparatus and its failure to account for contrasting political and institutional structures, diverging economic paths and social change propelled the modification of its assumptions and progressive conceptual innovation. In the later 1970s and early 1980s, North abandoned the efficiency view and gradually became more critical of the objective rationality postulate. In this intellectual movement, North's avant-garde research program contributed significantly to the creation of New Institutional Economics.
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Ram Al Jaffri Saad, Aidi Ahmi, Norfaiezah Sawandi and Norazita Marina Abdul Aziz
This study aims to identify the inputs from zakat administrators and experts needed for more efficient and effective zakat revenue generation.
Abstract
Purpose
This study aims to identify the inputs from zakat administrators and experts needed for more efficient and effective zakat revenue generation.
Design/methodology/approach
Face-to-face interviews with zakat executives, administrators and experts are conducted to collect data.
Findings
The findings show three components of input required in the zakat transformation: environment, resources and history. The environmental component comprises five sub-components: companies, banks, zakat recipients, individual zakat payers and the legislative, while the resource sub-components comprise tangible and intangible resources. For history, two components, namely, achievements and challenges, need to be taken into account by the zakat administration.
Research limitations/implications
This study’s main implication is that the components proposed in this study can serve as the basis for developing new strategies for improving zakat collection and distribution management to achieve a more efficient and effective level.
Practical implications
This study will be helpful for policymakers, especially zakat authorities, on how to enhance their administration.
Originality/value
The model developed in this study will help the zakat administration to reform and enhance zakat compliance and zakat revenue generation.
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William McColloch and Matías Vernengo
The rise of the regulatory state during the Gilded Age was closely associated with the development of institutionalist ideas in American academia. In their analysis of the…
Abstract
The rise of the regulatory state during the Gilded Age was closely associated with the development of institutionalist ideas in American academia. In their analysis of the emergent regulatory environment, institutionalists like John Commons operated with a fundamentally marginalist theory of value and distribution. This engagement is a central explanation for the ultimate ascendancy of neoclassical economics, and the limitations of the regulatory environment that emerged in the Progressive Era. The eventual rise of the Chicago School and its deregulatory ambitions did constitute a rupture, but one achieved without rejecting preceding conceptions of competition and value. The substantial compatibility of the view of markets underlying both the regulatory and deregulatory periods is stressed, casting doubt about the transformative potential of the resurgent regulatory impulse in the New Gilded Age.
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