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Raja Ampat, located in West Papua – Indonesia, is renowned as a favoured tourist destination for manta ray tourism. In the years following the pandemic, there has been a noticeable increase in the number of visitors. Despite the benefits from tourists' expenditures, however, managing the influx of tourists poses an ongoing challenge in promoting sustainable tourism. This chapter focuses on carrying capacity studies examining manta ray tourism's economic, social and physical aspects in the Dampier Strait – Raja Ampat. Data was collected through on-site observations, interviews and surveys. The study aims to contribute to efforts and actions to reduce adverse effects on manta ray populations and their environments while advancing conservation, educational initiatives and responsible tourism practices for manta ray sustainable tourism. In summary, recommendations for sustainable tourism practices are proposed, including collaboration between stakeholders to continue research and monitoring, enforce guidelines and support conservation initiatives.

As a result of space debris problem, it is necessary to deorbit uncontrollable satellites or repair them to extend mission duration to avoid sending a new satellite. The purpose of this paper is to develop a docking mechanism that can be easily customized for different missions, providing on-orbit servicing for nanosatellites.

This research outlines a system and mechanism design for the docking phase of on-orbit servicing to nanosatellites. The umbrella-inspired mechanism is designed with utmost simplicity to minimize the likelihood of failure. CAD, structural analyse and mechanism analyse tools are used for designing and analysing the system. To ensure that the design attains the desired durability, numerous iterations are conducted. A three-dimensional (3D)-printed prototype is generated for mechanism verification in laboratory conditions.

The aimed mechanism is generated successfully. A 3D-printed prototype is assembled to verify the mechanism. Also, an equation for customis the presented design is generated for different mission requirements in the future.

The usage of the proposed design can help increase the lifespan of satellites.

The primary innovation in this study is the development of a docking mechanism featuring a movable platform to provide servicing for nanosatellites in orbit. The mechanism presented can be displaced without initiating the unfolding process. This provides a customizable coupling distance for different mission requirements. Therefore, the presented mechanism can serve both different types of satellites and more than one satellite on-orbit with a cost-effective design. Also, the presented design can be easily customized to enable adaptation for the different mission requirements in the future.

This paper aims to study the combination of photochromic microcapsules, which use the ultraviolet (UV) rays for colour changing phenomena, and titanium oxide (TiO₂) nanoparticles (NPs), which block the UV rays by their photocatalytic activity in the sunlight on the cotton fabric.

The TiO₂ NPs mixed with photochromic printing paste are used for coating on cotton fabric and further curing is performed in a one-step process. The photochromic pigment printed fabric impregnated in a liquid solution is processed in a two-step process with two variables such as 1% TiO₂ and 2% TiO₂. The characterization of samples was done with a UV transmittance analyser, surface contact angle, antimicrobial test and fabric physical properties.

The UV protection of TiO₂-treated photochromic printed fabric was high and gives the ultraviolet protection factor rating of 2,000 which denotes almost maximum blocking of UV rays. The antibacterial activity of the one-step samples shows the highest 36 mm zone of inhibition (ZOI) against S. aureus (gram-positive) and 32 mm ZOI against E. coli (gram-negative) bacteria. The one-step sample shows the highest static water contact angle of 118.6° representing more hydrophobicity, whereas the untreated fabric is fully wetted (0.4°). In two-step processes, as the concentration of TiO₂ increased, the antibacterial activity, UV blocking and hydrophobicity became better.

This work achieves the multifunctional finishes by using photochromic microcapsules and NPs in a single process as a first attempt. The results inferred that one-step sample has achieved higher values in most of the tests conducted when compared to all other sample.

The purpose of the study is to classify the radiographic images into three categories such as fillings, cavity and implant to identify dental diseases because dental disease is a very common dental health problem for all people. The detection of dental issues and the selection of the most suitable method of treatment are both determined by the results of a radiological examination. Dental x-rays provide important information about the insides of teeth and their surrounding cells, which helps dentists detect dental issues that are not immediately visible. The analysis of dental x-rays, which is typically done by dentists, is a time-consuming process that can become an error-prone technique due to the wide variations in the structure of teeth and the dentist's lack of expertise. The workload of a dental professional and the chance of misinterpretation can be decreased by the availability of such a system, which can interpret the result of an x-ray automatically.

This study uses deep learning (DL) models to identify dental diseases in order to tackle this issue. Four different DL models, such as ResNet-101, Xception, DenseNet-201 and EfficientNet-B0, were evaluated in order to determine which one would be the most useful for the detection of dental diseases (such as fillings, cavity and implant).

Loss and accuracy curves have been used to analyze the model. However, the EfficientNet-B0 model performed better compared to Xception, DenseNet-201 and ResNet-101. The accuracy, recall, F1-score and AUC values for this model were 98.91, 98.91, 98.74 and 99.98%, respectively. The accuracy rates for the Xception, ResNet-101 and DenseNet-201 are 96.74, 93.48 and 95.65%, respectively.

The present study can benefit dentists from using the DL model to more accurately diagnose dental problems.

This study is conducted to evaluate dental diseases using Convolutional neural network (CNN) techniques to assist dentists in selecting the most effective technique for a particular clinical condition.

This paper aims to improve the tribological properties of lithium complex greases using nanoparticles to investigate the tribological behavior of single additives (nano-TiO₂ or nano-CeO₂) and composite additives (nano-TiO₂–CeO₂) in lithium complex greases and to analyze the mechanism of their influence using a variety of characterization tools.

The morphology and microstructure of the nanoparticles were characterized by scanning electron microscopy and an X-ray diffractometer. The tribological properties of different nanoparticles, as well as compounded nanoparticles as greases, were evaluated. Average friction coefficients and wear diameters were analyzed. Scanning electron microscopy and three-dimensional topography were used to analyze the surface topography of worn steel balls. The elements present on the worn steel balls’ surface were analyzed using energy-dispersive spectroscopy and X-ray photoelectron spectroscopy.

The results showed that the coefficient of friction (COF) of grease with all three nanoparticles added was low. The grease-containing composite nanoparticles exhibited a lower COF and superior anti-wear properties. The sample displayed its optimal tribological performance when the ratio of TiO₂ to CeO₂ was 6:4, resulting in a 30.5% reduction in the COF and a 29.2% decrease in wear spot diameter compared to the original grease. Additionally, the roughness of the worn spot surface and the maximum depth of the wear mark were significantly reduced.

The main innovation of this study is the first mixing of nano-TiO₂ and nano-CeO₂ with different sizes and properties as compound lithium grease additives to significantly enhance the anti-wear and friction reduction properties of this grease. The results of friction experiments with a single additive are used as a basis to explore the synergistic lubrication mechanism of the compounded nanoparticles. This innovative approach provides a new reference and direction for future research and development of grease additives.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0291/

Additive manufacturing (AM), a rapidly evolving paradigm, has shown significant advantages over traditional subtractive processing routines by allowing for the custom creation of structural components with enhanced performance. Numerous studies have shown that the technical qualities of AM components are profoundly affected by the discovery of novel metastable substructures in diverse alloys. Therefore, the purpose of this study is to determine the effect of cell structure parameters on its mechanical response.

Initially, a methodology was suggested for testing porous materials, focusing on static tensile testing. For a qualitative evaluation of the cellular structures produced, computed tomography (CT) was used. Then, the CT scanner was used to analyze a sample and determine its actual relative density, as well as perform a detailed geometric analysis.

The experimental research demonstrates that the mechanical properties of a cell’s structure are significantly influenced by its shape during formation. It was also determined that using selective laser melting to produce cell structures with a minimum single-cell size of approximately 2 mm would be the most appropriate method.

Further studies of cellular structures for testing their static tensile strength are planned for the future. The study will be carried out for a larger number of samples, taking into account a wider range of cellular structure parameters. An important step will also be the verification of the results of the static tensile test using numerical analysis for the model obtained by CT scanning.

The fabrication of metallic parts with different cellular structures is very important with a selective laser melted machine. However, the determination of cell size and structure with mechanical properties is quiet novel in this current investigation.

The study suggests that the high concentration of mining and metallurgical enterprises on the territory of the Russian Ural region determines the need to consider industrial waste, including nickel slag, as a possible raw material for the production of ceramic bricks. The article describes the properties of clays and nickel slag obtained at metallurgical enterprises in the Orenburg region and the features of their use as components in the composition of ceramic bricks.

To achieve this purpose, such tasks as determining the technological parameters of production, conducting the X-ray phase and microstructural analysis of the obtained samples were solved.

Compositions of ceramic mass using clay from the Khalilovsky deposit (Orenburg region) with the addition of nickel slag (20 and 40% by weight) have been developed, and their physical and mechanical properties (compressive strength, bending strength, water absorption and density) have been determined. With the help of modern research methods involving high-tech equipment, the microstructure is considered and the phase composition of the finished samples is determined. As a result of the conducted research, it was found that the composition of the selected clay and nickel slag in the obtained rational composition ensures the production of ceramic bricks of grades M175 and M200.

This is the first study on the use of nickel slag for the production of ceramic bricks. The results relate primarily to Russian feedstocks, but a methodology is presented that can be applied to other countries as well as to other silica-containing feedstocks.

Information and communication technologies (ICT) are indispensable tools for Knowledge Management (KM) practices in today’s knowledge-intensive and globally interconnected marketplace. This paper seeks to investigate the impact of family ownership on ICT investments in an emerging economy (EE) context.

This empirical paper uses data from 300 large Indian listed firms with 2,650 observations in the period 2008–2017, to test its hypothesis.

The results indicate that family firms are not favourably inclined towards ICT investments for formalizing their KM practices. However, under certain contexts, such as higher foreign institutional ownership or business group affiliation, they are more willing to invest in ICT resources.

This study establishes a nuanced understanding of how family firms approach ICT investments and KM practices. This research can help family owners/managers to commit sufficient resources on ICT projects.

Literature on KM has largely emanated from developed countries. This is one of the first papers from an EE context that studies the impact of family ownership on ICT investments and subsequent KM practices. In this way, this paper offers specific insights into the context of Indian family firms and offers some interesting findings that can contribute to the literature, policy and practice.

Sex and age estimation is important, particularly when information about the deceased is unavailable. There are limited radiological studies investigating side, sex and age differences in normal ankle morphometric parameters. The authors’ goal was to evaluate different ankle joint morphometric measurements and document variations among Egyptians.

A prospective study was conducted throughout 23 months on 203 (100 males and 103 females) adult Egyptians, aged between 20-69 years old, who were referred for a plain x-ray of bilateral normal ankle joints.

Ankle parameters showed no statistical difference between both sides, except for tarsal width (TaW) which was significantly higher on right than left side (26.92 ± 2.66 vs 26.18 ± 2.65 mm). Males showed significantly higher morphometric values except for anteroposterior gap (APG) and talus height (TaH) which were significantly higher in females (2.29 ± 0.80 vs 1.80 ± 0.61 mm and 13.01 ± 1.68 vs 11.87 ± 1.91 mm, respectively). There was significant increase in tibial arc length, APG, distance of level of MTiTh from anterior limit of mortise, distance of level of MTiTh from vertex of mortise, sagittal distance between tibial and talar vertices and sagittal radius of trochlea tali arc in old age group compared to young one. A significant decrease in tibial width, malleolar width, TaW and TaH was noted in old age group compared to young one.

Ankle joints of both sides are mostly symmetrical; however, there are significant differences in most morphometric values due to sex and age factors. These findings may be essential during side, sex and age determination.

The purpose of this study is to examine the impact of MoS₂ on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy through the addition of varying concentrations of MoS₂ particles to the electrolyte, aiming to enhance the corrosion resistance of magnesium alloy.

The surface morphology, roughness and phase composition of the coatings were analyzed using scanning electron microscopy, a hand-held roughness tester and an X-ray diffractometer, respectively, and the corrosion resistance of the MAO coatings prepared by the addition of different contents of MoS₂ particles was tested and analyzed using an electrochemical workstation.

The results demonstrate that MoS₂/MgO composite coatings have been successfully prepared on the surface of magnesium alloys through micro-arc oxidation. Furthermore, the corrosion resistance of the ZK60 magnesium alloy prepared with the addition of 1.0 g/L MoS₂ was the best compared to the other samples.

MoS₂ particles were able to penetrate the coatings successfully during the micro-arc oxidation process, acting as a barrier in the micropores to prevent the corrosion medium from touching the surface, thus improving the corrosion resistance of the sample. The electrochemical workstation was used to study the corrosion resistance of the MoS₂/MAO coating on the ZK60 magnesium alloy.