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Facility management gained profound importance due to the increasing complexity of different systems and the cost of operation and maintenance. However, due to the increasing complexity of different systems, facility managers may suffer from a lack of information. The purpose of this paper is to propose a new facility management approach that links segmented assets to the vital data required for managing facilities.

Automatic point cloud segmentation is one of the most crucial processes required for modelling building facilities. In this research, laser scanning is used for point cloud acquisition. The research utilises region growing algorithm, colour-based region-growing algorithm and Euclidean cluster algorithm.

A case study is worked out to test the accuracy of the considered point cloud segmentation algorithms utilising metrics precision, recall and F-score. The results indicate that Euclidean cluster extraction and region growing algorithm revealed high accuracy for segmentation.

The research presents a comparative approach for selecting the most appropriate segmentation approach required for accurate modelling. As such, the segmented assets can be linked easily with the data required for facility management.

The paper aims to describe the positive and negative effects of night lights in historical sites, as well as the most salient challenges faced by the visitors of these sites and determine ways to address them. The study aims to suggest several light-and-shadow approaches and designs to enhance the experience of visiting historical sites.

This study identifies problems of nightlife in historical sites with an online international questionnaire to determine the preferences and difficulties faced by visitors of historical sites during day and night. After that Egypt was determined as a sample case of a developing country; its archaeological sites need to be improved. The main problems of historical Egyptian sites were investigated and approaches in developing historical sites with interactive lighting design were presented after an online questionnaire to the Egyptian society.

The paper shows that archaeological sites need some development, especially in their technological and lighting aspects, to overcome visitors’ low night-time interest in archaeological sites. Research has found certain limitations in the effects of constructing artificial illumination. The study provides modern sustainable solution for some light challenges in historical sites with approaches and solutions to solve it.

The results of that research could be applied in developing countries, but with larger specific studies to the historical urban locations according to the politics of the country.

The paper includes sustainable approaches in developing historical sites with technological lighting design required to enhance historical sites at night-time and make visits more interactive and interesting.

This paper presents an identified need of historical sites visitors’ to study applying modern approaches in enhancing urban historical sites.

The purpose of this study is to reduce the gloss of the surface of silk fabrics, by treating the fabrics with tea and matting agent, to imitate the aging and retro effects of silk artefacts.

Silk fabrics were treated with different processing techniques. The aged appearance and surface gloss of the silk fabrics were characterised by sensory analysis, measurement of reflectivity, scanning electron microscopy, measurement of brightness and chroma to identify the influential factors.

The application of matting agent on silk fabrics could reduce the lustre of silk fabrics. Treated with matting agent and tea pigments, silk fabrics could be “aged” to achieve retro effects within a relatively short period of time. A number of other factors and mechanisms that affect the reflectivity of the silk fabrics were also identified.

There is no definite index to evaluate the antique effect of fabrics.

The method developed through this study provided a simple and practical solution to achieving aging and retro effects on silk fabrics.

The method for reducing the lustre of silk fabrics by treating them with matting agent is novel and the finding of the relationships among reflectivity and brightness and chroma is original.

The objective is to provide a quantitative insight on the dynamic nature of insolation on the building perimeter according to location, season and orientation. Such understanding is necessary for deciding on solar control strategies in diverse climatic environments, from low to high availability of insolation.

This study explores the seasonal changes of solar irradiation on building façades of various orientations at five locations with diverse climates (Reykjavík, London, Athens, Riyadh, Lagos). Solar data collected from the European PVGIS database is used to study the monthly distribution of global solar radiation incident on building façades at cardinal and ordinal orientations, as well as the proportions of its components.

The results illuminate the effects of the various factors on insolation. Among others: In all locations, horizontal surfaces receive more annual irradiation than any façade. In summer, east/west facades receive more radiation than south, hence solar protection on those directions is more important than on south. The beam fraction varies seasonally on south and north facades, but not so on east/west. Local atmospheric conditions can offset the importance of latitude on insolation levels and composition.

The paper utilises commonly available data to correlate insolation values and types under different factors across the globe, offering a better understanding on insolation for the design of greener buildings.

This article explores the impacts of the changing land-use on urban heat island (UHI) in an urban transformation zone in Ankara (Türkiye). Identifying a characteristic rural landscape until the 1950s, the study area experienced a drastic land-use change by razing the fertile landscape of the city and replacing it with a sealed surface. Development of the squatter houses after the 1960s and, subsequently, the implementation of a new housing morphology have introduced new sceneries, scales and surface conditions that make the study area a noteworthy case to analyze.

Regarding the drastic spatio-temporal change of the study area, this research assesses the impacts of the changing land-use on UHI based on three periods. Using 1957, 1991 and 2021 aerial imaginaries and maps, it analyzes the temperature alteration caused by the changing land-use. To do so, different surface types, green patterns and built-up areas have been modeled using Ankara climatic data and transferred to ENVI-Met to calculate the Universal Thermal Climate Index (UTCI) values.

The calculation has been developed over a transect covering an area of 40 m × 170 m, which includes diversity in terms of architecture, landscape and open space elements. To encourage future design strategies, the research findings deliberate into three extents that discuss the lacking climate knowledge in the ongoing urban transformation projects: impervious surface ratio and regional albedo variation, changing aspect ratio and temperature variation at the pedestrian level.

Urban transformation projects, being countrywide operations in Türkiye, need to cover climate-informed design strategies. Herein, the article underlines the critical position of design decisions in forming a climate-informed urban environment. Dwelling on a typical model of housing transformation in Türkiye, the research could trigger climate-informed urban development strategies in the country.

This chapter outlines complex and conflicting issues related to designing tall buildings. It gathers a vast amount of fragmented criticism and concerns and organizes them around the three pillars of sustainability: social, economic, and environmental. Mapping out the “unsustainable” aspects forms the foundation for addressing them in future research and tall building developments. The chapter engages the reader with a preliminary discussion on potential solutions to the outlined problems. It also balances extensive criticism by highlighting the virtues and advantages of tall buildings. Consequently, this chapter forms a foundation for improving the sustainability of tall buildings whenever and wherever they are constructed.

Material extrusion-based additive manufacturing is a prominent manufacturing technique to fabricate complex geometrical three-dimensional (3D) parts. Despite the indisputable advantages of material extrusion-based technique, the poor surface and subsurface integrity hinder the industrial application of this technology. The purpose of this study is introducing the hot air jet treatment (HAJ) technique for surface treatment of additive manufactured parts.

In the presented research, novel theoretical formulation and finite element models are developed to study and model the polishing mechanism of printed parts surface through the HAJ technique. The model correlates reflow material volume, layer width and layer height. The reflow material volume is a function of treatment temperature, treatment velocity and HAJ velocity. The values of reflow material volume are obtained through the finite element modeling model due to the complexity of the interactions between thermal and mechanical phenomena. The theoretical model presumptions are validated through experiments, and the results show that the treatment parameters have a significant impact on the surface characteristics, hardness and dimensional variations of the treated surface.

The results demonstrate that the average value of error between the calculated theoretical results and experimental results is 14.3%. Meanwhile, the 3D plots of Ra and Rq revealed that the maximum values of Ra and Rq reduction percentages at 255°C, 270°C, 285°C and 300°C treatment temperatures are (35.9%, 33.9%), (77.6%,76.4%), (94%, 93.8%) and (85.1%, 84%), respectively. The scanning electron microscope results illustrate three different treatment zones and the treatment-induced and manufacturing-induced entrapped air relief phenomenon. The measured results of hardness variation percentages and dimensional deviation percentages at different regimes are (8.33%, 0.19%), (10.55%, 0.31%) and (−0.27%, 0.34%), respectively.

While some studies have investigated the effect of the HAJ process on the structural integrity of manufactured items, there is a dearth of research on the underlying treatment mechanism, the integrity of the treated surface and the subsurface characteristics of the treated surface.

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

Window shading has always been an effective technique to control the access of solar radiation; however, inappropriate selection of the shading technique, location and optical properties may lead to an increase in energy consumed for cooling and artificial lighting. Venetian blinds (VBs) are a type of adjustable shading devices that can be installed to the interior, exterior or in between glass panes of a window and that can be easily implemented in both new and existing buildings. This study aims to investigate the impact of three VB parameters: slat angle, reflectivity and location on the overall energy consumption of a residential space with a south-facing facade under the hot arid desert climate of Saudi Arabia’s capital, Riyadh. For the purpose of globalizing the findings, the same investigations were applied for two other cities of similar climates: Cairo, Egypt, and Arizona, the USA.

A test room was modelled for energy simulation, with a 20% window-to-wall ratio. A VB was assigned with alternatives of being located to the indoor, outdoor or in between double glass panes. High, medium and low reflectivity values were applied at each location at slat angle alternatives of 15°, 30°, 45°, 60°, 75° and 90°.

Results showed VB performance across slat angles, where up to 20.1% energy savings were achieved by mid-pane high reflectivity VBs in Riyadh, while the value exceeded 30% in case of being externally located. A similar performance pattern occurred in the other two cities of hot arid desert climates: Cairo and Arizona.

The study is limited to VBs at a fixed position, with no upward movement for partial or full openness conditions. The effect of blind control and operation on performance, such as the amount and duration of openness/closure of the blind and changes in slat angle across time, in addition to VB automation, shall be investigated in a future study.

The better understanding of VB energy performance achieved would enhance a more rational selection of VBs, which would benefit the construction industry as it would assist designers, real estate developer companies, as well as end-users in the decision-making process and help to realize energy-efficient solutions in residential buildings. VB production entities would also benefit by manufacturing and promoting for energy-efficient products.

In this study, a matrix of combinations of three VB parameters was developed, and the effect of these combinations on the overall energy consumption of both artificial lighting and heating, ventilation and air conditioning (HVAC) systems was evaluated and compared to identify the combinations of higher efficiency. The literature showed that these three parameters were hardly investigated in a combined form and hardly assessed by considering the overall energy consumed by both artificial lighting and HVAC.

The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.