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The purpose of this study is to enable the planning of construction projects with simultaneous consideration of time, cost and safety risks. It also aims to improve the decision-making process by evaluating the effectiveness of the Rao-2 algorithm in solving multi-objective time-cost-safety risk problems. In the end, this model is designed to support project managers in enhancing management approaches by addressing project challenges and constraints more efficiently.

In this study, the Rao-2 algorithm, along with Grey Wolf Optimization (GWO) and Whale Optimization algorithm (WOA), were improved using the crowding distance-based non-dominated sorting method. Rao-2 was first compared to GWO and WOA. Subsequently, it was compared with well-established algorithms in the literature, including genetic algorithm (GA), particle swarm optimization (PSO) and differential evolution (DE). The C-metric, hypervolume and spread metrics were employed for performance measurement. The performance of the algorithms was evaluated on four case studies consisting of 11, 13, 18 and 25 activities.

The results revealed that Rao-2 performs better than other algorithms as the number of activities increases, when compared using the Hypervolume, Spread and C-metric measures. In terms of performance measures, the GWO algorithm outperformed Rao-2 in some evaluation metrics for the instance involving 11 activities. However, as the number of activities grew, the Rao-2 method consistently generated higher-quality Pareto fronts and outperformed GWO and WOA in all evaluation metrics. The solutions generated by Rao-2 were also superior to those obtained from GA, PSO and DE in all case studies, further demonstrating the capability of our framework to produce a wide range of optimal solutions with high diversity across different case studies.

This research demonstrates that Rao-2 not only improves solution quality when generating Pareto fronts but also achieves better results with fewer function evaluations compared to GA, PSO and DE. The algorithm's efficiency makes it particularly well-suited for optimizing time, cost and safety risks in large-scale construction projects, which in turn positions Rao-2 as a better choice for such projects by producing superior results compared to other algorithms. By providing high-quality solutions with reduced computational demands, Rao-2 offers a faster and more resource-efficient tool for decision-making, contributing to advancements in both the theory and practice of construction project management.

This study aims to determine the effects of three different carrier system materials (laminated wooden beams, post-tensioned concrete beams and steel beams) used widely in interior spaces on the perceptual evaluations of respondents.

The large opening Olympic swimming pool space was chosen as the research environment. A total of 376 university graduates participated. After experiencing the 360-degree virtual images of the experimental spaces, a “spatial perception” questionnaire was applied to these respondents.

The spaces using the laminated wood beams in the carrier system were perceived as warmer, lighter, more attractive, more spacious, more informal, closer, more well-planned, freer, simpler, more peaceful, more exciting, and uncrowded compared to the spaces that used post-tensioned concrete beams and steel beams. The architect respondents made more negative perceptual evaluations for all the adjective pairs compared to the respondents in the other professional groups. Respondents who were males, and in the 26–35 years of age group, perceived more positively the physical environmental factors of the virtual swimming pools compared to females, and the 36 years of age or above age group.

The results set forth that the structural elements of buildings, such as ceilings, walls and furnishings, were not only systematic elements used in the formation of the structure, they were also important environmental factors in the perceptual evaluation of the space.

The purpose of this paper is to develop new four-dimensional (4D) hyperchaotic system by adding another state variable and linear controller to three-dimensional T chaotic dynamical systems. Its dynamical analyses, circuit experiment, control and synchronization applications are presented.

A new 4D hyperchaotic attractor is achieved through a simulation, circuit experiment and mathematical analysis by obtaining the Lyapunov exponent spectrum, equilibrium, bifurcation, Poincaré maps and power spectrum. Moreover, hardware experimental measurements are performed and obtained results well validate the numerical simulations. Also, the passive control method is presented to make the new 4D hyperchaotic system stable at the zero equilibrium and synchronize the two identical new 4D hyperchaotic system with different initial conditions.

The passive controllers can stabilize the new 4D chaotic system around equilibrium point and provide the synchronization of new 4D chaotic systems with different initial conditions. The findings from Matlab simulations, circuit design simulations in computer and physical circuit experiment are consistent with each other in terms of comparison.

The 4D hyperchaotic system is presented, and dynamical analysis and numerical simulation of the new hyperchaotic system were firstly carried out. The circuit of new 4D hyperchaotic system is realized, and control and synchronization applications are performed.

The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering.

HIP process and HIP + T6 heat treatments were applied to as stress-relieved direct laser metal sintered (DMLS) AlSi10Mg parts. Aging times of 4 and 12 h are selected to examine the optimum duration. To analyze the advantages of HIP process, a T6 heat treatment with 4 h of aging was also applied. Densities, open porosities and roughness values of as stress-relieved, HIPed, HIP + T6, and T6-only samples were measured. The samples were characterized by OM and SEM together with EDX analysis. An image analysis study was made to evaluate the inner pore structure, thereby to understand the mechanical behavior.

HIP process does not cause a significant change in surface porosity; yet it has a positive influence on inner porosity. HIP process results in a microstructure of the aluminum matrix surrounded by a network of micron and nano size Si particles. Additional heat treatment results in larger particles and precipitation. After HIPing, ductility increases but strength decreases. Samples aged 4 h present improved yield and tensile strength but decreased elongation, yet samples aged for 12 h reach a combination of optimum strength and ductility. The lower level of tensile strength and ductility in T6-only condition indicates that HIP process plays a crucial role in elimination of the porosity thus improves the effectiveness of subsequent heat treatment.

The study investigates the effect of post-process conditions and optimizes the aging time of the T6 heat treatment after HIP process in order to obtain improved mechanical properties. The stress-relieved state was chosen as the reference to prevent distortion during HIPing or heat treatment.

The present paper aims to systematically investigate the influence of building orientations (0°, 15°, 30°, 45°, 60°, 75°) and heat treatment processes on the macro-/micro-structural, mechanical and electrochemical behaviors of selective laser melting (SLM) prepared AlSi10Mg alloy parts.

AlSi10Mg samples were produced by the SLM method using standard processing parameters at 0°, 15°, 30°, 45°, 60° and 75° building angles. The effects of building orientations on the physical, mechanical and electrochemical properties of the alloy were investigated.

With the increase in the building orientation from 15° to 75°, the structural defects were found reducing. The effect of step size of inclined geometries was found to significantly influence the mechanical and electrochemical properties of the AlSi10Mg samples. Tensile strength for samples fabricated at lower angles (0°, 15°, 30°) reported a drop of approximately 11% than SLM 0° samples. Moreover, the tensile strength was found to decrease from 412.35 ± 9.568 MPa for the as-built samples to 290.48 ± 12.658 MPa, whereas the fracture strain increases from 3.32 ± 0.56% to 5.6 ± 0.6% when the as-built sample was treated with T6 treatment. This study indicates that the microstructure and mechanical properties of SLM-processed AlSi10Mg alloy can be tailored by a suitable heat treatment or building angle.

Microstructural and mechanical behavior of horizontal or vertically built SLM components have already been demonstrated several times. However, the influence of different building orientations, such as 0°, 15°, 30°, 45°, 60°, 75°, has not been explored in-depth, particularly on corrosion and general mechanical performance. As a result, this work may be of significant relevance to academics and designers, given the varying orientation of internal component of SLM structures.

Over the recent years, solar energy has received outstanding attention from researchers. Solar energy applications and related large-scale projects are increasing to meet growing global energy demand as an economical, non-polluting and renewable energy source. The purpose of this study is investigating different plenum and absorber configurations of solar air heating wall (SAHW) experimentally and numerically.

In this study, various configurations of SAHW have been numerically simulated to determine the most effective design. According to the simulation results, two SAHWs with various plenum thicknesses have been fabricated and tested at different conditions.

Numerical simulation results indicated that parallel-flow SAHWs exhibited better performance in comparison with other placements of absorber plate. Regarding to the experimentally attained results, the highest thermal efficiency was reached to 80.51%. Also, the average deviation between experimentally and numerically obtained outlet temperature is 5.5%.

Considering the obtained results in the present study, designed SAHW has admissible efficiency to be used in various industrial and residential applications such as; air preheating, space heating and drying.

This paper aims to investigate the effects of various heat treatments on microstructure, hardness, porosity and corrosion properties of the parts.

Hot isostatic pressing (HIP) process, various heat treatments and their combinations were applied to the AlSi10Mg parts produced by direct laser metal sintering (DMLS).

It has been found that the HIP process, which is a post-processing process, reduces the amount of porosity in DMLS-AlSi10Mg material, thus improves corrosion resistance significantly.

In this study, the HIP process and subsequent T6 heat treatments were applied to AlSi10Mg parts produced by the DMLS technique. The study aims to increase the corrosion resistance of AlSi10Mg parts by reducing porosity with the HIP process and by altering the microstructure with the T6 process.

The aim of this study is to analyze the gastronomy festivals in Türkiye within the scope of the United Nations sustainable development goals.

In line with this purpose, a systematic review approach, which is a qualitative research method, was adopted as the method of the study. In the study, the data was collected with document analysis technique by accessing secondary sources. Systematic literature review was used to analyze the data.

When the gastronomy-themed festivals in Türkiye are analyzed, it is seen that 23 of them are in line with at least one of the United Nations sustainable development goals. The number of festivals organized in accordance with more than one of these goals is 18. The number of festivals organized in accordance with at least one goal is 5. The fact that only 23 of the 351 festivals in the research universe are organized in accordance with the United Nations sustainable development goals reveals that festivals are insufficient in terms of sustainability.

This study adopts theoretical approaches such as the experience economy, as it provides unforgettable consumption experiences for both producers and consumers participating in gastronomy festivals, and stakeholder theory, as festivals involve many stakeholders. The study also presents practical approaches, such as supporting local development, which is one of the primary objectives of festivals.

This study has revealed the sustainability status of gastronomy festivals in Türkiye which have been taken into consideration more frequently in recent years. It may also contribute to the literature to examine the organized gastronomy festivals within the scope of the UN sustainable development goals.

While the current knowledge in the field of educational leadership and management (EDLM) has been primarily based on research produced in English-speaking Western societies, there have been significant efforts by other societies to contribute to the knowledge production, especially during the past decade. The purpose of this paper is to identify the contribution of Turkey to the international EDLM literature by investigating the topical focus, conceptual frameworks and research designs of papers published by EDLM scholars from Turkey.

Descriptive content analysis method was employed to examine 315 empirical, review, conceptual and commentary papers published by Turkish scholars in core educational administration and Web of Science journals. The time period of the review left open-ended. However, in practical terms, it begins in the year 1994 when the first article from Turkey was published in any of the selected sources and ends at the end of 2018. Information relevant to the research was extracted from each article and was coded to facilitate quantitative analysis. Using Excel software, descriptive statistics including frequencies and percentages were provided for each research question.

Results show that Turkish EDLM scholars mostly rely on survey based quantitative research approach, employing advanced statistical techniques in the analysis of the data. However, mixed method and qualitative studies are relatively less common. Organizational behavior, school leadership and emotions stand out as most frequently used topics, while Turkish scholars are not interested in analyzing the educational outcomes such as student achievement and school improvement. Consistent with the findings related to topical foci, a large number of those who were interested in correlational studies examined the relationship between leadership roles and organizational behaviors.

The data set only included journal articles and excluded conference proceedings, books and theses/dissertations. Nevertheless, the authors believe this review adds significantly to previous reviews of local EDLM journals conducted by Turkish scholars. The authors concluded that the Turkish scholars should direct their future research to exploring and better understanding the practices of Turkish principals in schools by: diversifying their research topics; incorporating more qualitative and mixed-method designs; and taking into account specific features of the culture and educational system in Turkey.

Based on the current higher education context, reducing scholars’ teaching load, diversifying research funding opportunities, and modifying access to tenure tracks seem necessary interventions to support EDLM research with strong ties to practice and to the sociocultural context. In addition, policy changes aiming professionalization of administrative positions and establishing some forms of formal training for school principalship are needed. Such changes can help transfer the knowledge produced by the Turkish EDLM researchers to the practice and provide solutions to problems related to school administration.

This paper will add to recent effort to identify how a developing nation outside Western perspective approaches the field, and contributes to the global knowledge base.

This study intends to systematically review empirical evidence on transformational school leadership (TSL) in a centralized educational context.

The study includes a topographical mapping and a narrative review of thirty-seven research articles published in Turkey between 2000 and 2021. The review strategy included systematically searching the Turkish Academic Network and Information Center (ULAKBIM) and Scopus. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram guided the review and reporting process.

Three key themes emerged: (1) perceptions, attitudes and behaviors; (2) psychological resources, learning and innovation and (3) school climate and culture. The results indicated that the research evidence on TSL in the review did not correspond well with the evidence on TSL in non-Western contexts. The authors also discussed the state of research narratively to provide an overview of the topical foci and methodological and conceptual trends.

First, although the databases of the study are claimed to be regularly updated locally, these two search databases may inevitably have missed some journal articles relevant to the inclusion criteria. A possible solution is to include more databases like ERIC, PsycArticles, SAGE, ScienceDirect, PsycINFO, Web of Science and ProQuest. Second, the authors decided to limit the exploration of journal articles on transformative leadership to peer-reviewed journal articles. The authors might have missed a wider range of insights available in book chapters, books, research papers, dissertations and gray literature. Third, as there were many levels of research foci, the authors did the coding on research foci and methods. However, the approach may not allow authors to explore the relationships between research foci and method design. One possible solution is to do all coding in one file so that more complex analysis can follow. Finally, the authors agree that TSL is only one leadership style that is related to leadership effectiveness and that effective leadership is multi-faceted and requires a combination of leadership styles. Accordingly, the evidence in the study sheds light on only one dimension of leadership effectiveness.

Our review is part of an effort to demonstrate the importance of a culturally-situated understanding of TSL and to develop a globally validated knowledge base. It identifies and summarizes research in a non-Western school context defined by centrality, lack of autonomy and accountability.