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This study proposes a DfMA (Design for Manufacture and Assembly) based on unmanned aerial vehicle (UAV) and uses Iranian-Islamic Muqarnas as the main case study due to their geometric modularity. In Islamic architecture, different geographic regions are known to have used various design and construction methods of “Muqarnas”, a type of decorated dome.

The paper presents a study on parametric analysis of the Iranian-Islamic Muqarnas and analyses its components, geometric relations and construction methods that should be considered when constructing one. This study aims to use the Muqarnas analysis as a driver to generate a DfMA basis on the UAVs and parametric fabrication. In Islamic architecture, different geographic regions use various design and construction methods of Muqarnas. There are four main parameters of the Muqarnas that define their classification; first, their three-dimensional shape, that provides volume. Second, the size of their modules is variable. Third, their own specific generative process-algorithm, and finally, the two-dimensional pattern plan that is used as a basis in the design. Thus, the authors present a global analytical study that drives a generative system to construct Muqarnas, through a careful balance of the four parameters.

This study thus presents a global analytical study that drives a generative system to construct Muqarnas, through a careful balance of four specifications. The paper reports the result of using a parametric tool, Grasshopper and parametric plugins, for creating a generative system of several types of Muqarnas. This synthetic translation aims at expanding our understanding of parametric analysis and synthesis of traditional architecture, advancing our understanding towards using parametric synthesis, with the scope to fabricate and assemble modules towards UAV-based fabrication of Muqarnas. To do so, the authors are taking advantage of their inherent repetition and recursion.

In the first step, this paper reviews studies on traditional Muqarnas (both Iranian and non-Iranian) and relevant parametric approaches. In the second step, the study aims to create a general generative system for Muqarnas. The creation of a generative system for Muqarnas is driven towards the creation of three-dimensional fabrication of their components so that these are assembled automatically using a swarm of UAVs. This particular drive imposes specific constraints in the parametric system, as the assembly of the final components, the authors posit, can only take place in a pick and place fashion.

The existence of the regional Kuznets curve, i.e. an inverted U-shaped relationship between regional disparity and economic development is widely debated and discussed. The bell-shaped curve of the spatial growth process where during the initial phase inequality increases and then reduces is theoretically supported by Myrdal (1957), Hirschman (1958), and Williamson (1965). It becomes important to understand regional Kuznets curve globally. Understanding the relationship between regional disparity and economic development becomes essential for public policy for balanced regional growth.

Regional Kuznets Curve which is an inverted U-shaped relationship between regional disparity and economic development is not a new phenomenon. Theoretical framework by Myrdal (1957), Hirschman (1958), and Williamson (1965) support the an inverted U-shaped relationship. To understand the relationship between regional disparity and economic development, the authors investigate the regional Kuznets curve by using data for 184 countries and 1765 subnational regions. Using parametric, semi-parametric, and non-parametric, it is found that there exists an inverted U-shaped relationship between regional disparity and economic development. The presence of the regional Kuznets curve is observed. As the theoretical framework suggests, regional inequality increases with income initially and decreases after attaining a certain level of income. This study identifies two stages of divergence-convergence where in the first stage, divergence across regions in a country happens with increasing income and in the later stage, convergence across regions in a country occurs with increasing income.

Using the parametric approach (panel data analysis), semi-parametric and non-parametric approaches, it is found that there exists a regional Kuznets curve. It is found that there exists an inverted-U relationship between regional inequality and per capita GNI. This suggests that the divergence-convergence passes through two stages. In the first stage, divergence across regions in a country happens with increasing income while in the later stage convergence occurs.

This research work has done three important things which fill the research gap that exists in the literature: (1) constructing the Gini coefficient to measure the regional inequality for 184 countries using 1765 subnational regional data; (2) using a parametric approach (panel data analysis) to understand the regional Kuznets phenomenon and (3) using a semi-parametric approach and non-parametric approach to understand the regional Kuznets phenomenon.

Describes non‐parametric methods applied to comparisons of three or more sample groups.Illustrates non‐parametric ANOVA applied to a randomized block design for a consumer sensory experiment.

In this study, the performance analysis of the split flow turbofan engine with afterburners has been examined using the parametric cycle analysis method. The purpose of this study is to examine how engine performance is impacted by design parameters and flight ambient values and to develop a software in this context.

Software has been developed using the open-source PYTHON programming language to perform performance analysis. Mach number, compressor/fan pressure ratio, bypass ratio and density were used as parameters. The effects of these variables on engine performance parameters were investigated.

Parametric cycle analysis has been calculated for different flight conditions in the range of 0–2 M and 0–15,000 m altitude for turbofan engines. With this study, basic data were obtained to optimize according to targeted flight conditions.

As a result of the performance analysis, the association between the flight conditions and design parameters of engine were determined. A software has been developed that can be used in the design of supersonic gas turbine engines for fast and easy simulation of the design parameters.

The variables used in the literature have been analyzed, and the results of the studies have been incorporated into the developed software, which can be used in innovative engine design. Software is capable to be developed further with the integration of new algorithms and models.

The purpose of this paper is to investigate the willingness of households to pay for academic and deprivation-compensating components of the Contextual Value Added (CVA) indicator of school quality used in England in order to locate themselves in the catchment area of state schools. Deprivation-compensating school performance, defined as the difference in the disadvantaged intake between two schools with the same academic performance.

The empirical analysis, based on data drawn from three independent UK data sources, used parametric and non-parametric analysis approaches. The analysis conducted separately for primary and secondary schools, because household behaviour can differ between these two levels of education.

Consumers are willing to pay for houses in the catchment area of primary and secondary schools with high academic achievement, as measured by the mean score; whereas, the component of the CVA indicating deprivation-compensating aspects of school performance is found to have a positive effect only on the price of houses in the catchment area of primary schools in London; its impact on the price of houses elsewhere is mostly negative.

The analysis in this study suggested that the recently adopted practice of using CVA as a measure of school quality in England can encourage government and Local Authorities to pay more attention to raising the deprivation-compensating aspects of school performance of their schools.

This is the first study to explore the value which households attach to deprivation-compensating outcomes, at a given level of academic performance using the CVA indicator.

The effectiveness of any government interventions to support small firms is always a concern in achieving improvements in enterprise performances. The purpose of this paper is to evaluate thoroughly the impact of micro and small enterprises’ (MSEs’) support programs on core intermediate and final outcomes of interest.

The impact evaluation employs a non-parametric matching procedure for parametric outcome analysis using the propensity score matching (PSM) method. Aiming at a doubly robust evaluation process, the study applies parametric analyses than non-parametric permutation-based tests to investigate the causal effects of the public intervention.

The study reveals that the public intervention encouraged MSEs to develop innovative business practices and improve their human capital development process. Moreover, the intervention had a positive effect in expanding employment opportunities in urban areas. Contrariwise, the study shows that support beneficiaries are not at an advantage in investment intensity. The lower level of investment intensity on fixed capital resulted inefficiency among the recipients. Moreover, the intervention did not have an effect on changing the net-asset over time for the recipients.

This study implies that the support programs need to be dynamic and also targets on creating innovative high-growth MSEs.

This paper is fairly original and provides policy makers and MSE promoters/facilitators evidence-based information on the effectiveness of the support services, with looking at firm-level analysis.

Though many studies in the past dealt with the survival and growth of enterprises both in the local- and export-markets, less attention was given to the analysis of the duration of enterprises entry into the export-markets. The aim of this paper is, therefore, to analyze the duration of Ethiopian enterprises entry into the export-markets.

This paper used data collected from 848 enterprises through a cross-sectional survey method conducted by the World Bank in 2015. In order to estimate the average duration – the time that enterprises need to wait before entering into the export-markets and the associated factors – the authors used the mixture of non-parametric (Kaplan-Meier) and parametric (Weibull) models.

The non-parametric results show that enterprises are required to wait for an average of about eight years before entering into the export-markets after their establishment. In addition, foreign-owned enterprises were found to be faster in entering into the export-markets than their domestically owned counterparts. The parametric results revealed that enterprises’ product innovation, enterprises’ size and age, and custom and trade regulations are factors that curtail the durations of enterprises entry into the export-markets. On the other hand, enterprises’ operational costs, the size of enterprises’ locality, and enterprises’ location are factors that slow the durations of enterprises’ entry into the export-markets.

This study is the first to offer pioneering evidences on the duration (time in years) that Ethiopian enterprises need to wait before entering into the export-markets and the factors that affect the length of their waiting time.

This study aims to present comprehensive nonlinear material modelling techniques and simulations of reinforced concrete (RC) beams subjected to short-term monotonic static load using the robust and reliable general-purpose finite element (FE) software ANSYS. A parametric study is carried out to analyse the flexural and ductility behaviour of RC beams under various influencing parameters.

To develop and validate the numerical FE models, a total of four experimentally tested simply supported RC beams are taken from the available literature and two beams are selected from each author. The concrete, steel reinforcements, bond-slip mechanism, loading and supporting plates are modelled using SOLID65, LINK180, COMBIN39 and SOLID185 elements, respectively. The validated models are then used to conduct parametric FE analysis to investigate the effect of concrete compressive strength, percentage of tensile reinforcement, compression reinforcement ratio, transverse shear reinforcement, bond-slip mechanism, concrete compressive stress-strain constitutive models, beam symmetry and varying overall depth of beam on the ultimate load-carrying capacity and ductility behaviour of RC beams.

The developed three-dimensional FE models can able to capture the load and midspan deflections at critical points, the accurate yield point of steel reinforcements, the formation of initial and progressive concrete crack patterns and the complete load-deflection curves of RC beams up to ultimate failure. From the numerical results, it can be concluded that the FE model considering the bond-slip effect with Thorenfeldt’s concrete compressive stress-strain model exhibits a better correlation with the experimental data.

The ultimate load and deflection results of validated FE models show a maximum deviation of less than 10% and 15%, respectively, as compared to the experimental results. The developed model is also capable of capturing concrete failure modes accurately. Overall, the FE analysis results were found quite acceptable and compared well with the experimental data at all loading stages. It is suggested that the proposed FE model is a practical and reliable tool for analyzing the flexural behaviour of RC members and can be used for performing parametric studies.

Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term implantation. Therefore, the fine process tuning plays its crucial role to develop optimal settings to achieve these desired properties. This paper aims to find applications for fine process tuning in laser powder bed fusion of biomedical Ti alloys for load-bearing implants.

In this work, the parametric porosity simulations were initially performed to simulate the process-induced porosity for selective laser-melted Ti₆Al₄V as per full factorial design. Continually, the experiments were performed to validate the simulation results and perform multiresponse optimization to fine-tune the processing parameters. Three levels of each control variable, namely, laser power – Pl (180, 190, 200) W, scanning speed – Vs (1500, 1600, 1700) mm/s and scan orientation – ϴ{1(0,0), 2(0,67°), 3(0,90°)} were used to investigate the processing performance. The measured properties from this study include compressive yield strength, elastic modulus, process-induced porosity and surface roughness. Finally, confirmatory experiments and comparisons with the already published works were also performed to validate the research results.

The results of porosity parametric simulation and experiments in selective laser melting of Ti₆Al₄V were found close to each other with overall porosity (less than 10%). The fine process tuning was resulted in optimal settings [Pl (200 W), Vs (1500 mm/s), ϴ (0,90°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,67°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] and [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] with higher compressive strength (672.78 MPa), near cortical bone elastic modulus (12.932 GPa), process-induced porosity (0.751%) and minimum surface roughness (2.72 µm). The morphology of the selective laser melted (SLMed) surface indicated that the lack of fusion pores was prominent because of low laser energy density among the laser and powder bed. Confirmatory experimentation revealed that an overall percent improvement of around 15% was found between predicted and the experimental values.

Since no significant works are available on the collaborative optimization and fine process tuning in laser powder bed fusion of biomedical Ti alloys for different load bearing implants. Therefore, this work involves the comprehensive investigation and multi-objective optimization to determine optimal parametric settings for better mechanical and physical properties. Another novel aspect is the parametric porosity simulation using Ansys Additive to assist in process parameters and their levels selection. As a result, selective laser melted Ti alloys at optimal settings may help in examining the possibility for manufacturing metallic implants for load-bearing applications.

In fire condition, the limiting temperature of a restrained steel beam depends on a few parameters, e.g. temperature distributions along and across the beam, beam’s load ratio and span length. The purpose of this study is to investigate the structural fire behaviour of axially restrained steel beams under different beam’s load ratios, taking into consideration the effect of the beam’s end connections configuration.

A three-dimensional finite element (FE) computer model has been developed to simulate the structural fire behaviour of axially restrained steel beams and their end connections. After successfully validating the developed model against the outcomes of the available large-size fire resistance experiments, the FE model has been used in a parametric study to investigate the beam’s load ratio effect on the behaviour of the axially restrained steel beams and their end connections.

The parametric study showed that increasing the beam loading level significantly increased the beam deflections at elevated temperatures; where, increasing the beam’s load ratio from 0.5 to 0.9 reduced the beam fire resistance by about 100 s. In contrast, decreasing the beam’s load ratio from 0.5 to 0.3 allowed the beam to easily achieve a 30-min fire resistance rating with no fire protection applied.

Experimental parametric studies are difficult to control in a laboratory setting and are also expensive and time consuming. Therefore, the reasonable accuracy of the validated FE model in reproducing the experimental fire behaviour of steel beams and their end connections makes it a very useful tool for both numerical and analytical studies.