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1 – 10 of over 2000This paper examines the Pakistani state's shift from the accommodation to exclusion of the heterodox Ahmadiyya community, a self-defined minority sect of Islam. In 1953, the…
Abstract
This paper examines the Pakistani state's shift from the accommodation to exclusion of the heterodox Ahmadiyya community, a self-defined minority sect of Islam. In 1953, the Pakistani state rejected demands by a religious movement that Ahmadis be legally declared non-Muslim. In 1974 however, the same demand was accepted. This paper argues that this shift in the state's policy toward Ahmadis was contingent on the distinct political fields in which the two religious movements were embedded. Specifically, it points to conjunctures among two processes that defined state–religious movement relations: intrastate struggles for political power, and the framing strategies of religious movements vis-à-vis core symbolic issues rife in the political field. Consequently, the exclusion of Ahmadis resulted from the transformation of the political field itself, characterized by the increasing hegemony of political discourses referencing Islam, shift toward electoral politics, and the refashioning of the religious movement through positing the “Ahmadi issue” as a national question pertaining to democratic norms.
Adnan Rasul, Saravanan Karuppanan, Veeradasan Perumal, Mark Ovinis, Mohsin Iqbal and Khurshid Alam
Stress concentration factors (SCFs) are commonly used to assess the fatigue life of tubular T-joints in offshore structures. SCFs are usually estimated from parametric equations…
Abstract
Purpose
Stress concentration factors (SCFs) are commonly used to assess the fatigue life of tubular T-joints in offshore structures. SCFs are usually estimated from parametric equations derived from experimental data and finite element analysis (FEA). However, these equations provide the SCF at the crown and saddle points of tubular T-joints only, while peak SCF might occur anywhere along the brace. Using the SCF at the crown and saddle can lead to inaccurate hotspot stress and fatigue life estimates. There are no equations available for calculating the SCF along the T-joint's brace axis under in-plane and out-of-plane bending moments.
Design/methodology/approach
In this work, parametric equations for estimating SCFs are developed based on the training weights and biases of an artificial neural network (ANN), as ANNs are capable of representing complex correlations. 1,250 finite element simulations for tubular T-joints with varying dimensions subjected to in-plane bending moments and out-of-plane bending moments were conducted to obtain the corresponding SCFs for training the ANN.
Findings
The ANN was subsequently used to obtain equations to calculate the SCFs based on dimensionless parameters (α, β, γ and τ). The equations can predict the SCF around the T-joint's brace axis with an error of less than 8% and a root mean square error (RMSE) of less than 0.05.
Originality/value
Accurate SCF estimation for determining the fatigue life of offshore structures reduces the risks associated with fatigue failure while ensuring their durability and dependability. The current study provides a systematic approach for calculating the stress distribution at the weld toe and SCF in T-joints using FEA and ANN, as ANNs are better at approximating complex phenomena than typical data fitting techniques. Having a database of parametric equations enables fast estimation of SCFs, as opposed to costly testing and time-consuming FEA.
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Adnan Rasul, Saravanan Karuppanan, Veeradasan Perumal, Mark Ovinis and Mohsin Iqbal
The stress concentration factor (SCF) is commonly utilized to assess the fatigue life of a tubular T-joint in offshore structures. Parametric equations derived from experimental…
Abstract
Purpose
The stress concentration factor (SCF) is commonly utilized to assess the fatigue life of a tubular T-joint in offshore structures. Parametric equations derived from experimental testing and finite element analysis (FEA) are utilized to estimate the SCF efficiently. The mathematical equations provide the SCF at the crown and saddle of tubular T-joints for various load scenarios. Offshore structures are subjected to a wide range of stresses from all directions, and the hotspot stress might occur anywhere along the brace. It is critical to incorporate stress distribution since using the single-point SCF equation can lead to inaccurate hotspot stress and fatigue life estimates. As far as we know, there are no equations available to determine the SCF around the axis of the brace.
Design/methodology/approach
A mathematical model based on the training weights and biases of artificial neural networks (ANNs) is presented to predict SCF. 625 FEA simulations were conducted to obtain SCF data to train the ANN.
Findings
Using real data, this ANN was used to create mathematical formulas for determining the SCF. The equations can calculate the SCF with a percentage error of less than 6%.
Practical implications
Engineers in practice can use the equations to compute the hotspot stress precisely and rapidly, thereby minimizing risks linked to fatigue failure of offshore structures and assuring their longevity and reliability. Our research contributes to enhancing the safety and reliability of offshore structures by facilitating more precise assessments of stress distribution.
Originality/value
Precisely determining the SCF for the fatigue life of offshore structures reduces the potential hazards associated with fatigue failure, thereby guaranteeing their longevity and reliability. The present study offers a systematic approach for using FEA and ANN to calculate the stress distribution along the weld toe and the SCF in T-joints since ANNs are better at approximating complex phenomena than standard data fitting techniques. Once a database of parametric equations is available, it can be used to rapidly approximate the SCF, unlike experimentation, which is costly and FEA, which is time consuming.
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Navid Nazhand, Reza Dashti and Abolfazl Ahmadi
The purpose of this paper is to describe a novel method to compromise between planned (regulated) maintenance and outage initiation and unplanned (unregulated) maintenance and to…
Abstract
Purpose
The purpose of this paper is to describe a novel method to compromise between planned (regulated) maintenance and outage initiation and unplanned (unregulated) maintenance and to find an economic model using which one can perform maintenance adequately and in the most optimal state.
Design/methodology/approach
In this paper, a system consisting of similar components is considered, and the role of each component in the system is explained. Then, the cost pertaining to failure in each asset is determined. Costs such as energy not supplied, penalties, human resources to resolve the defect and replacing assets are taken into account. Finally, a new comprehensive objective is proposed, and optimization is performed for a sample system.
Findings
In this paper, some graphs have been plotted from which plenty of information may be extracted. This is mentioned in the Conclusion.
Originality/value
In this paper, some graphs have been plotted from which plenty of information may be extracted. This is mentioned in the Conclusion.
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Ali Ahmadi Azar, Payam Jalili, Bahram Jalili and D.D. Ganji
This study examines fluid flow within a rectangular porous medium bounded by walls capable of expansion or contraction. It focuses on a non-Newtonian fluid with Casson…
Abstract
Purpose
This study examines fluid flow within a rectangular porous medium bounded by walls capable of expansion or contraction. It focuses on a non-Newtonian fluid with Casson characteristics, incompressibility, and electrical conductivity, demonstrating temperature-dependent impacts on viscosity.
Design/methodology/approach
The flow is two-dimensional, unsteady, and laminar, influenced by a small electromagnetic force and electrical conductivity. The Hybrid Analytical and Numerical Method (HAN method) resolves the constitutive differential equations.
Findings
The fluid’s velocity is influenced by the Casson parameter, viscosity variation parameter, and resistive force, while the fluid’s temperature is affected by the radiation parameter, Prandtl number, and power-law index. Increasing the Casson parameter from 0.1 to 50 results in a 4.699% increase in maximum fluid velocity and a 0.123% increase in average velocity. Viscosity variation from 0 to 15 decreases average velocity by 1.42%. Wall expansion (a from −4 to 4) increases maximum velocity by 19.07% and average velocity by 1.09%. The average fluid temperature increases by 100.92% with wall expansion and decreases by 51.47% with a Prandtl number change from 0 to 7.
Originality/value
Understanding fluid dynamics in various environments is crucial for engineering and natural systems. This research emphasizes the critical role of wall movements in fluid dynamics and offers valuable insights for designing systems requiring fluid flow and heat transfer. The study presents new findings on heat transfer and fluid flow in a rectangular channel with two parallel, porous walls capable of expansion and contraction, which have not been previously reported.
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Ayat Ahmadi, Leila Doshmangir, Vladimir Sergeevich Gordeev, Bahareh Yazdizadeh and Reza Majdzadeh
Underreporting of new tuberculosis (TB) cases is one of the main problems in TB control, particularly in countries with high incidence and dominating role of a private sector in…
Abstract
Purpose
Underreporting of new tuberculosis (TB) cases is one of the main problems in TB control, particularly in countries with high incidence and dominating role of a private sector in TB cases diagnosing. The purpose of this paper was to explore behavioral determinants of underreporting of new TB cases among private sector physicians in Iran.
Design/methodology/approach
The authors conducted a population-based, cross-sectional study of physicians working in private clinics. The data collection tool was designed using the theory of planned behavior (TPB). The authors used structural equation models with maximum likelihood estimation to examine attitude toward the notification behavior.
Findings
Of 519 physicians, 433 physicians completed the questionnaire. Attitude toward notification had the highest score (mean score = 87.65; sd = 6.79; range: 0–100). The effect of perceived behavioral controls on the notification behavior (
Practical implications
Considering stronger effect of perceived behavioral control on the behavior, interventions aiming at facilitating notification process would be more effective than those aiming at changing the attitude or enhancing intention among physicians.
Originality/value
To the best of our knowledge, no other study previously explored determinants of underreporting from the behavioral and cognitive perspective. Specifically, the authors explored the role of the TPB constructs in predicting intention to notify new TB cases.
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Kamran Zolfi and Javid Jouzdani
As far as the authors know, no research has already been carried out on the multi-floor dynamic facility layout problem (MF-DFLP) in the continuous form regarding the flexible bay…
Abstract
Purpose
As far as the authors know, no research has already been carried out on the multi-floor dynamic facility layout problem (MF-DFLP) in the continuous form regarding the flexible bay structure, the number and the variable location of the elevator. Therefore, the present paper models the given problem and attempts to find a sub-optimal solution for it using a meta-heuristic simulated annealing (SA) algorithm.
Design/methodology/approach
The efficient use of resources has always been a prominent matter for decision-makers. Many reasons including land use, construction considerations and proximity of departments have led to the design of multi-floor facilities. On the other hand, their fast-evolving environment calls for dynamic planning. Therefore, in this paper, a model and the SA algorithm for MF-DFLP are presented.
Findings
After presenting a mathematical model, the problem was solved precisely in a small size using the GAMS software. Also, a near-optimal solution method using a SA meta-heuristic algorithm is suggested and the proposed algorithm was run in the MATLAB software. To evaluate the presented model and the proposed solution, some test cases were considered in two aspects. The first aspect was the test cases that are newly generated in small, medium and large sizes to compare the exact optimal solution with the results of the meta-heuristic algorithm. Eight test cases with small sizes were solved using the GAMS software, the optimum solutions were obtained in a reasonable time, and the cost of their solutions was equal to that of the SA algorithm. Eight test cases with medium sizes were run in the GAMS software with the time limit of 80,000 s, and the SA algorithm had performed better for these test cases. Two test cases were also considered in large size that GAMS could not solve them, whereas the SA algorithm successfully found a proper solution for each. The second aspect included the test cases from the literature. The result showed that suggested algorithm is more capable of finding best solutions than compared algorithms.
Originality/value
In this paper, an unequal area MF-DFLP was studied in a continuous layout form in which the location and number of the elevators were considered to be variable, and the layouts were considered with flexible bay structure. These conditions were investigated for the first time.
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Hisham Abusaada and Abeer Elshater
Sustainable development (SD) is vital in alleviating poverty, hunger and disease (PHD). The purpose of this study is to present a guiding framework with pathways targeting the…
Abstract
Purpose
Sustainable development (SD) is vital in alleviating poverty, hunger and disease (PHD). The purpose of this study is to present a guiding framework with pathways targeting the sustainability challenges concerning PHD based on urban planning and design literature.
Design/methodology/approach
A narrative review and content analysis of 27 articles published by 11 journals indexed in Scopus were conducted using bibliometrics analysis.
Findings
The study’s findings discuss contemporary normative planning and design ideas and their ability to alleviate PHD. Considering these findings, the authors recommend that urban planning and design implementation processes carefully pursue the United Nations Sustainable Development Goals (SDGs) and Vision 2030 by tracking qualitative metrics that consider social, cultural and spiritual well-being.
Originality/value
The contribution is to propose a conceptual framework for alleviating hunger, poverty and disease through Vision 2030. Practitioners and policymakers can use this framework to assess the impact of their actions. Hunger, poverty and disease research could be guided by this framework to identify and prioritize best practices in cities of the Global South.
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Sunday Olayinka Oyedepo, Richard Olayiwola Fagbenle, Samuel Sunday Adefila and Md Mahbub Alam
This study aims to use an environomics method to assess the environmental impacts of selected gas turbine power plants in Nigeria.
Abstract
Purpose
This study aims to use an environomics method to assess the environmental impacts of selected gas turbine power plants in Nigeria.
Design/methodology/approach
In this study, exergoenvironomic analysis has been carried out to investigate the environmental impact of selected gas turbine power plants in Nigeria from an exergetic point of view.
Findings
The exergy analysis reveals that the combustion chamber is the most exergy destructive component compared to other cycle components. The exergy destruction of this component can be reduced by increasing gas turbine inlet temperature (GTIT). The results of the study show that thermodynamic inefficiency is responsible for the environmental impact associated with gas turbine components. The study further shows that CO2 emissions and cost of environmental impact decrease with increasing GTIT.
Originality/value
The exergo-environomic parameters computed in this study are CO2 emission in kg per MWh of electricity generated, depletion number, sustainability index, cost flow rate of environmental impacts (Ċenv) in $/h and total cost rates of products (ĊTot) in $/hr. For the period considered, the CO2 emissions for the selected plants vary from 100.18 to 408.78 kgCO2/MWhm, while cost flow rate of environmental impacts varies from $40.18 /h to $276.97 /h and the total cost rates of products vary from $2935.69/h to $12,232.84/h. The depletion number and sustainability index vary from 0.69 to 0.84 and 1.20 to 1.44, respectively.
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A. Ahmadi and S.B.M. Beck
The sensitivity of orifice plate metering to poorly conditioned and swirling flows are subjects of concerns to flow meter users and manufacturers. The distortions caused by pipe…
Abstract
Purpose
The sensitivity of orifice plate metering to poorly conditioned and swirling flows are subjects of concerns to flow meter users and manufacturers. The distortions caused by pipe fittings and pipe installations upstream of the orifice plate are major sources of this type of non‐standard flows. These distortions will alter the accuracy of metering up to an unacceptable degree.Design/methodology/approach – The design of orifice plate meters that are independent of the initial flow conditions of the upstream is a major object of flow metering. Either using a long straight pipe or a flow conditioner upstream of an orifice plate usually achieves this goal. The effect of cone swirler flow conditioner for both standard and non‐standard flow conditions has been carried out in the experimental rig. The measuring of mass flow rate under different conditions and different Reynolds numbers were used to establish a change in discharge coefficient relative to a standard one.Findings – The experimental results using the cone swirler flow conditioner showed that the combination of an orifice plate and cone swirler flow conditioner is broadly insensitive to upstream disturbances. The results clearly show that this flow conditioner can attenuate the effect of both swirling and asymmetric flows on metering to an acceptable level.Originality/value – Previous work on the orifice plate has shown that the concept has promise. The results of using a combination of a cone swirler and orifice plate for non‐standard flow conditions including swirling flow and asymmetric flow show this package can preserve the accuracy of metering up to the level required in the standards, providing that a new discharge coefficient is used for the combined swirler and orifice plate.
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