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Several trillion cigarettes produced worldwide annually lead to many thousands of kilograms of toxic waste. Cigarette butts (CBs) accumulate in the environment due to the poor biodegradability of the cellulose acetate filters. This paper presents some of the results from a continuing study on recycling CBs into fired clay bricks. The results show that the density of fired bricks was reduced by up to 30%, depending on the percentage of CBs incorporated into the raw materials. Similarly, the compressive strength of bricks tested decreased according to the percentage of CBs included in the mix. Nevertheless, by increasing mixing times, better quality bricks can be produced, even with the inclusion of high percentages of CBs. Longer mixing times increased dry density and compressive strength, equivalent to about 53% and 11% respectively. Microstructure observation using ESEM confirm the result by showing the apparent size of pores is reduced drastically and the distribution of pores becomes more uniform as the mixing time increases from 5 to 15 minutes, hence decreasing the porosity in the clay body which subsequently leads to a denser product with higher strength.

The potential for massive economic growth exists in Samarinda City due to the intensification of activities in built-up areas. This suggests the potential for increased urban disease in the relocation of Indonesia’s new capital city to a location adjacent to Samarinda. One of the most striking impacts is the urban heat island (UHI). The increase in this phenomenon can be addressed effectively and efficiently through the provision and arrangement of appropriate vegetation-based actions. Therefore, this study aims to identify priority areas of green open space (GOS) based on UHI levels. In addition, this study also aims to present alternative mitigation measures to reduce the risk of disasters due to UHI.

A mixed-method approach was used in this research, involving an initial land surface temperature analysis to identify the UHI class. This analysis was complemented by quantitative spatial analyses, such as scoring, overlay and intersect methods, to determine the priority level class and the typology of GOS priority. A qualitative analysis was also conducted through data triangulation or comparison methods, such as examining existing land use, GOS priority maps and spatial plan policies.

The findings show that the total UHI area in Samarinda City was 6,936.4 ha in 2019 and is divided into three classifications. In Class 1, the UHI area is very dominant, reaching 87% of the total area. Meanwhile, the main results identified two priority classes of GOS in Samarinda, namely, the medium and high categories with an area of 960.43 ha and 113.57 ha, respectively. The results also showed that there were 17 typologies associated with five alternative mitigation measures: green industry, greening parking lots, improving urban green infrastructure and buildings, urban greening and mining restoration.

Specific to assessing UHI, image data were available only in medium spatial resolution, leading to a consequence of detailed accuracy. In addition, since the determination of mitigation considered local policies, the method should be used in other locations requiring adjustments to existing regulations, specifically those related to spatial planning.

This study makes a significant contribution to the understanding of the UHI phenomenon in Indonesia, especially in the urban areas of Kalimantan Island. In addition, the study presents new insights into alternative mitigation actions to reduce the risk of UHI. Innovatively, this study introduces a typology of regions associated with appropriate alternative mitigation actions, making it an important achievement for the first time in the context of this study.

This paper aims to study the effect of the addition of water treatment plant sludge (WTPS) and processed tea waste (PTW) on the properties of burnt clay bricks. The reuse of WTP sludge as a raw material for brick production is a long-term approach, to sludge disposal, for economic and environmental sustainability. Sludge have been added at 10, 20, 30 and 40% and processed tea waste at 5% (by weight) in replacement of clay for brick manufacturing. Each batch of hand-moulded bricks was fired in a heat controlled furnace at a temperature of 990°C. The compressive strength has been found to increase with the sludge content, however, a slight decrease in compressive strength was observed with tea waste addition. Further, PTW addition has improved the thermal insulation of bricks as compared to controlled bricks. The study shows that 40% WTPS, 5% PTW and 55% natural clayey soil can be considered as an optimum mix for bricks with good compressive strength as well as improved thermal insulation property.

Four different mixing ratios of sludge at 10, 20, 30 and 40% of the total weight of sludge-clay mixtures were used to make bricks. Similarly, PTW was investigated as a substitute of natural clayey soil in brick manufacturing. Each batch of hand-moulded bricks was fired in a heat controlled furnace at a temperature of 990°C. The physical, mechanical and engineering properties of the produced WTPS bricks and PTW bricks were determined and evaluated according to various Indian Standard Codes of Specification for burnt clay bricks and certain reference books.

The results exhibited that WTP sludge and PTW can be used to produce good quality brick for various engineering applications in construction and building. Increasing the sludge content increases the compressive strength. Moreover, thermal insulation of PTW bricks depicted an upward trend when compared to controlled bricks. Hence, an optimum mixture of 40% WTPS, 5% PTW and 55% natural clayey soil was found, at which bricks showed good compressive strength as well as improved thermal insulation property of the building material.

The present work provides a sustainable solution for disposal of WTP sludge and tea waste. Utilization of these waste materials in brick manufacturing is viable and economic solution.

Bricks with 40% WTP sludge and 5% processed tea waste proved to be economic, technically sound for construction purposes with added thermal insulation properties.

Bulk amount of waste such as WTP sludge is a threat to society owing to its environmental implications of disposal. Authors propose to use WTP sludge and tea waste for brick manufacturing and provide a solution to its disposal.

Water treatment plant sludge along with tea waste have not been tried for brick manufacturing so far. Hence, the composition is new in itself and also have resulted into good performance.

This study aims to develop an efficient algorithm for generation of conforming mesh for seepage analysis through 3D discrete fracture networks (DFN).

The algorithm is developed based on a refined conforming Delaunay triangulation scheme, which is then validated using analytical solutions. The algorithm is well able to meet the challenge of meshing complex geometry of DFNs.

A series of sensitivity analysis have been performed to evaluate the effect of meshing parameters on steady state solution of Darcy flow using a finite element scheme. The results show that an optimized minimum internal angle of meshing elements should be predetermined to guarantee termination of the algorithm.

The developed algorithm is computationally efficient, fast and is of low cost. Furthermore, it never changes the geometrical structure and connectivity pattern of the DFN.

Bales of cotton run through the gins and textile mill instruments, stick to them and make it cumbersome for the ginning mill workers. This is so because more time and money have to be invested in cleaning these instruments. The stickiness of cotton causes health hazards to the workers, decreases the yarn quality and economic loss to the textile industry. The effect of cotton stickiness on textile ginning, various methods for cotton stickiness detection and the steps for reduction are discussed.

The different methods that are available for detecting and measuring cotton stickiness are described. The sugars that cause stickiness are either of plant origin (physiological sugars) or from the feeding insects (entomological origin). The methods for stickiness detection and reduction are discussed under physical, chemical and biological categories.

This review suggests possible ways to mitigate cotton stickiness.

One of the major issues of the textile industry is honeydew-contaminated cotton stickiness. However, there are few papers on detection methods for analyzing honeydew cotton stickiness along with the approaches to reduce stickiness. This paper summarizes different methods along with a study for detection as well as reduction of cotton stickiness.

The textile sector struggles with cotton stickiness from honeydew contamination. It hurts agriculture and marketability. This study aims to examine how bacterial enzymes could reduce honeydew-contaminated cotton adherence in textile businesses sustainably.

Enzyme was extracted from bacteria isolated from the fermented bamboo shoots “Lung siej”. The enzyme was tested for α-glucosidase using p-nitrophenyl-α-D-glucopyranoside as a substrate. Design of experiments determined enzyme activity temperature and reaction time. Laboratory-prepared artificial honeydew was added to ginning mill cotton to show honeydew contamination. After enzyme treatment, sticky cotton was tested for microscopic examination, ultraviolet (UV), Benedict’s, Elsner colorimetric, high volume instrument (HVI) and viscosity tests.

The bacterial isolate is characterized as Lysinibacillus sp. as confirmed by 16S rRNA gene sequencing. The enzyme extracted was identified as α-glucosidase. The ideal temperature and reaction time for enzymatic activity were 32 °C and 35 min, respectively, using central composite design. The microscopic examination, UV test, Benedict’s test, Elsner colorimetric test, HVI test and viscosity test showed that bacterial enzyme treatment reduced cotton fiber adherence.

Although few patents have examined the effect of yeast enzymes, to the best of the authors’ knowledge, a bacterial enzyme is investigated for the first time to reduce the adhesion of honeydew-contaminated cotton.

This study aims to explore the feasibility of adding Si₃N₄ nanoparticles to Sn58Bi and provides a theoretical basis for designing and applying new lead-free solder materials for the electronic packaging industry.

In this paper, Sn58Bi-xSi₃N₄ (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0 Wt.%) was prepared for bonding Cu substrate, and the changes in thermal properties, wettability, microstructure, interfacial intermetallic compound and mechanical properties of the composite solder were systematically studied.

The experiment results demonstrate that including Si₃N₄ nanoparticles does not significantly impact the melting point of Sn58Bi solder, and the undercooling degree of solder only fluctuates slightly. The molten solder spreading area reached a maximum of 96.17 mm², raised by 19.41% relative to those without Si₃N₄, and the wetting angle was the smallest at 0.6 Wt.% of Si₃N₄, with a minimum value of 8.35°. When the Si₃N₄ nanoparticles reach 0.6 Wt.%, the solder joint microstructure is significantly refined. Appropriately adding Si₃N₄ nanoparticles will slightly increase the solder alloy hardness. When the concentration of Si₃N₄ reaches 0.6 Wt.%, the joints shear strength reached 45.30 MPa, representing a 49.85% increase compared to those without additives. A thorough examination indicates that legitimately incorporating Si₃N₄ nanoparticles into Sn58Bi solder can enhance its synthetical performance, and 0.6 Wt.% is the best addition amount in our test setting.

In this paper, Si₃N₄ nanoparticles were incorporated into Sn58Bi solder, and the effects of different contents of Si₃N₄ nanoparticles on Sn58Bi solder were investigated from various aspects.

This paper aims to explore the ubiquitous role of the smartphone in expanding entrepreneurial opportunity among women in emerging Asia. This study attempted to explore the hidden issues behind increased innovative entrepreneurial tendency.

This study used a mixed research methodology. First, prior research based on different aspects of entrepreneurial tendency was reviewed in a systematic way. Second, a person-administered survey was conducted based on 265 women who are involved in entrepreneurial activities in different regions in Asia. Structural equation modeling (Amos) is used to analyze the person-administered survey.

Results show a significant relationship among the independent and dependent variables of the study which indicates a significant entrepreneurship opportunity for women in emerging Asia.

This study was conducted with a limited number of entrepreneurs from a few Asian countries which may affect the generalizability of the result.

This study fulfills the gap in the current literature by analyzing innovativeness in entrepreneurship with the usage of smartphones and increased tendency among women to conduct business.

The functioning of multi-gene genetic programming (MGGP) algorithm suffers from the problem of difficulty in model selection. During the preliminary analysis, it is observed that there are many models in the population whose performance is better than that of the model selected with a little compromise on training error. Therefore, an ensemble evolutionary (Ensemble-MGGP) approach is proposed and applied to the data obtained from the vibratory finishing process. The paper aims to discuss these issues.

Unlike the standard GP, each model participating in Ensemble-MGGP approach is made by combining the set of genes. Predicted residual sum of squares criterion (PRESS) criterion is integrated to improve its evolutionary search. The parametric analysis and sensitivity analysis (SA) conducted on the proposed model validates its robustness by unveiling dominant input parameters and hidden non-linear relationships.

The results indicate that the proposed Ensemble-MGGP model outperforms the standardized MGGP model. SA and parametric analysis reveals relationships and insights into vibratory finishing process.

Literature emphasises on characterization of vibratory finishing process using the experimental-based-studies. In addition, the issue of difficulty in model selection in genetic programming is addressed. This work proposes a new ensemble evolutionary approach to counter these issues.

Understanding the fluid flow through rock masses, which commonly consist of rock matrix and fractures, is a fundamental issue in many application areas of rock engineering. As the equivalent porous medium approach is the dominant approach for engineering applications, it is of great significance to estimate the equivalent permeability tensor of rock masses. This study aims to develop a novel numerical approach to estimate the equivalent permeability tensor for fractured porous rock masses.

The radial point interpolation method (RPIM) and finite element method (FEM) are coupled to simulate the seepage flow in fractured porous rock masses. The rock matrix is modeled by the RPIM, and the fractures are modeled explicitly by the FEM. A procedure for numerical experiments is then designed to determinate the equivalent permeability tensor directly on the basis of Darcy’s law.

The coupled RPIM-FEM method is a reliable numerical method to analyze the seepage flow in fractured porous rock masses, which can consider simultaneously the influences of fractures and rock matrix. As the meshes of rock matrix and fracture network are generated separately without considering the topology relationship between them, the mesh generation process can be greatly facilitated. Using the proposed procedure for numerical experiments, which is designed directly on the basis of Darcy’s law, the representative elementary volume and equivalent permeability tensor of fractured porous rock masses can be identified conveniently.

A novel numerical approach to estimate the equivalent permeability tensor for fractured porous rock masses is proposed. In the approach, the RPIM and FEM are coupled to simulate the seepage flow in fractured porous rock masses, and then a numerical experiment procedure directly based on Darcy’s law is introduced to estimate the equivalent permeability tensor.