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This study aims at enhancing the performance of a 16-stage axial compressor and improving the operating stability. The adopted approaches for upgrading the compressor are artificial neural network, optimization algorithms and computational fluid dynamics.

The process starts with developing several data sets for certain 2D sections by means of training several artificial neural networks (ANNs) as surrogate models. Afterward, the trained ANNs are applied to the 3D shape optimization along with parametrization of the blade stacking line. Specifying the significant design parameters, a wide range of geometrical variations are considered by implementation of appropriate number of design variables. The optimized shapes are analyzed by applying computational fluid dynamic to obtain the best geometry.

3D optimal results show improvements, especially in the case of decreasing or elimination of near walls corner separations. In addition, in comparison with the base geometry, numerical optimization shows an increase of 1.15 per cent in total isentropic efficiency in the first four stages, which results in 0.6 per cent improvement for the whole compressor, even while keeping the rest of the stages unchanged. To evaluate the numerical results, experimental data are compared with obtained data from simulation. Based on the results, the highest absolute relative deviation between experimental and numerical static pressure is approximately 7.5 per cent.

The blades geometry of an axial compressor used in a heavy-duty gas turbine is optimized by applying artificial neural network, and the results are compared with the base geometry numerically and experimentally.

This study aims to explore how users’ movement is influenced by different hospital ward layouts, by using space syntax theory. This study also compared four circulation patterns to find the best one for the study goal.

The authors used both qualitative and quantitative methods to study how users’ wayfinding in hospitals depends on various indicators and factors. The study used Depth Map software to do case studies and then analyzed the indicators from theoretical foundations and used the Pearson Test to check the correlation between indicators. This study also looked at Iran’s Ministry of Health standards for ward layouts. Finally, the results obtained from the research data were compared to achieve a suitable model based on the research objectives.

The linear-patterned plan was the best for easy wayfinding and accessibility among four patterns. The optimal hospital circulation patterns can improve wayfinding and reduce wayfinding problems and user movement.

By pioneering space syntax in hospital research, this study unveils the novel interaction between path architecture and user movement. It gives new insights into current trends, helping architects, administrators and policymakers improve health-care design, efficiency and patient experience.

In this study, two postprocessing techniques, namely, conventional burnishing (CB) and ultrasonic-assisted burnishing (UAB), were applied to improve the fatigue behavior of 316 L stainless steel fabricated through selective laser melting (SLM). The effects of these processes on surface roughness, porosity, microhardness and fatigue performance were experimentally investigated. The purpose of this study is to evaluate the feasibility and effectiveness of ultrasonic-assisted burnishing as a preferred post-processing technique for enhancing the fatigue performance of additively manufactured components.

All samples were subjected to a sandblasting process. Next, the samples were divided into three distinct groups. The first group (as-Built) did not undergo any additional postprocessing, apart from sandblasting. The second group was treated with CB, while the third group was treated with ultrasonic-assisted burnishing. Finally, all samples were evaluated based on their surface roughness, porosity, microhardness and fatigue performance.

The results revealed that the initial mean surface roughness (Ra) of the as-built sample was 11.438 µm. However, after undergoing CB and UAB treatments, the surface roughness decreased to 1.629 and 0.278 µm, respectively. Notably, the UAB process proved more effective in eliminating near-surface pores and improving the microhardness of the samples compared to the CB process. Furthermore, the fatigue life of the as-built sample, initially at 66,000 cycles, experienced a slight improvement after CB treatment, reaching 347,000 cycles. However, the UAB process significantly enhanced the fatigue life of the samples, extending it to 620,000 cycles.

After reviewing the literature, it can be concluded that UAB will exceed the capabilities of CB in terms of enhancing the surface roughness and, subsequently, the fatigue performance of additive manufactured (AM) metals. However, the actual impact of the UAB process on the fatigue life of AM products has not yet been thoroughly researched. Therefore, in this study, this paper used the burnishing process to enhance the fatigue life of 316 L stainless steel produced through the SLM process.

Increased dietary salt content is one of the effective factors of hypertension and a major public health challenge globally. Although the positive effects of dietary salt reduction on health are universally accepted, people can hardly reduce their salt intake. The purpose of this study is to identify the inhibitory factors of dietary salt reduction among 20–65-year-old women in Yazd City, Iran.

This study was conducted using a deductive content analysis approach based on the communication for the behavioral impact (COMBI) framework. The purposeful sampling method was applied with maximum variation in terms of different educational levels, age groups, occupational status and residential areas to select the participants. Snowball sampling was used to select health-care professionals. Furthermore, semi-structured interviews and focus-group discussions were conducted with 31 local women and 11 health-care professionals working in the City until data saturation was achieved. Data were analyzed using Graneheim and Landsman’s method.

After data analysis, 617 initial codes were extracted over the perceived barriers. After merging similar codes, 223 codes were extracted. The barriers were classified into five main categories of family, personal, organizational, educational and socio-cultural barriers.

Based on the COMBI framework, the results demonstrated that the most important barriers for reducing salt intake were negative attitude toward restrictions on dietary salt intake, insufficient and incorrect beliefs about the health risk of salt, lack of family support, inadequate health literacy and low self-efficacy in Yazd City. Among these barriers, lack of family support was considered as the most effective factor in reducing salt consumption. So, by focusing on this area and providing the community with the required education, the amount of salt consumed by families can be reduced.

This study aims to investigate the effect of mechanical peening on the cooling rate of a subsequently deposited layer in a hybrid additive manufacturing (AM) process.

In this experimental study, 20 layers of 316 L stainless steel are built via directed energy deposition, with the tenth layer being subject to various peening processes (shot peening, hammer peening and laser shock peening). The microstructure of the eleventh layer of all the samples is then characterized to estimate the cooling rate.

The measurements indicate that the application of interlayer peening causes a reduction in primary cellular arm spacing and an increase in micro segregation as compared to a sample prepared without interlayer peening. Both factors indicate an increase in the cooling rate brought about by the interlayer peening.

This work provides insight into process design for hybrid AM processes as cooling rates are known to influence mechanical properties in laser-based AM.

To the best of the authors’ knowledge, this work is the first of its kind to evaluate the effects of interlayer peening on a subsequently deposited layer in a hybrid AM process.

The last reformation in Iran’s population policy was announced inside “General Population Policy” (GPP) in 2013. One of the main objectives of the GPP is controlling population aging. The aim was to designing and evaluating different scenarios for achieving this objective.

For this purpose, a system dynamics model was built from cohort age groups. The model simulated Iran’s population structure from 2000 to 2050. The system dynamics model was validated in 2000 till 2011 period (R² = 94%). Data were extracted from the United Nations population division repository and represent a reducing trend in the fertility rate of Iran. This situation was named the “base” scenario. The simulation results for this scenario showed that Iran will face aging such that between 2000 and 2050 the median age will increase from 25 to 43 years. Based on these results, the base scenario could not achieve the GPP objective. So three alternative scenarios were designated: stabilization, increasing and hyper increasing.

The median age and the aging index are descending only in the hyper increasing scenario which means controlling aging. Therefore, the hyper increasing scenario is the only way to realize the GPP’s objective. To realize the hyper increasing scenario, it is essential to consider the total dependency ratio which shows the level of pressure on the workforce. Reducing this pressure increases the propensity to have more children (fertility index) and this is essential for maintaining high fertility rate.

The value of the research rests on a precise simulation model to forecast the population structure and aging. The research will serve as a guide for Iranian policymaker and support strong recommendations to bring the GPP along with supporting policies such as childbearing and child care assistance.

Many devices needed electrical power to work, thus, major energy carriers such as oil and gas were used to generate electrical power via converter mechanisms and special technologies. The microturbine is a developed technology that is remarkable for its relatively high performance and ability to use several types of fuels. Microturbines are economically feasible because of the production of combined heat and power and small-scale applicability. This study aims to investigate microturbine technology development to support modern energy access in a developing country (i.e. Iran).

This paper presents a technology foresight methodology to create plausible futures of microturbine development in Iran when the country faces different driving forces and uncertainties. On other hand, the paper deals with a theoretical question: how to select appropriate foresight methodology? A procedure is proposed, which equipped the research team to select appropriate method combinations based on Popper’s diamond. Finally, the selected methodology includes defining focal issues environmental scanning and patent analysis aimed at developing five plausible scenarios for microturbine development future in Iran and creating shared visions among policymakers.

This paper proposed a series of scenarios on the path to developing microturbine technology. The scenario development logic in a participatory way contains a common four-quarter technique that attempts to depict scenarios based on two critical uncertainties inclusive energy price and technology obsolescence, which will shape the future. Also, a scenario is presented to describe a wild card that can disturb the desired futures. Such materials help decision-makers to policies under plausible conditions that guarantee a robust policy basket.

The originality of this paper can be studied based on two aspects, first, the methodology that provides a systematic method selections procedure in an emerging complex technology development program. Second, from the practical aspect, this paper is one of the very first attempts to manage the microturbine technology development program. Then, results are used to feed the policy-making process in Iran.