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This study explored the effects of incorporating RA into geopolymer concrete, particularly examining its performance under ambient and elevated temperatures ranging from ambient temperature to 700°C.

The current study incorporates RA to replace conventional aggregates in the mix, with replacement levels ranging from 0 to 50%. Each mix designation is identified by a unique ID: RA0, RA10, RA20, RA30, RA40 and RA50, representing the percentage of RA used. The alkaline-to-binder ratio adopted for this study is 0.43.

The compressive strength starts at 50.51 MPa for 0% RA and decreases to 39.12 MPa for 50% RA after 28 days. It is highest with 0% RA and diminishes as the RA content increases. All mixes show a slight increase in compressive strength when heated to 100°C. However, the compressive strength starts to decrease for all mixes at 300°C. At 700°C, there is a drastic drop in compressive strength for all mixes, indicating significant structural degradation at this temperature.

The study evaluates the qualitative impact of RA on the properties of geopolymer concrete when exposed to severe temperatures. The experimental setup included several tests to assess the concrete mixes' mechanical properties and responses. Specifically, the researchers conducted compressive, flexural and split tensile strength tests.

The purpose of this paper is to investigate how the rising domestic food price inflation in India is influenced by global macroeconomic factors like crude oil, exchange rate, foreign aid, global food prices and trade openness from January 1993 to December 2022.

The study has employed the structural break, autoregressive distributed lag cointegration tests to assess the stationarity and long-term relationship between the variables and the Toda–Yamamoto Granger causality test to demonstrate the causal relationship between the variables.

The study highlights the long-term relationships among variables, shedding light on the influence of global macroeconomic factors on domestic food price inflation in India. It reveals that food price inflation in India is positively influenced by crude oil prices and global food prices while being negatively affected by currency rates, foreign direct investment and trade openness.

Based on the findings, the study suggests that initiatives to reduce demand for crude oil and imported food products could help mitigate domestic food price inflation in India. Addressing the depreciation of the exchange rate is crucial to combat significant inflation in domestic food prices, calling for specific government interventions. Furthermore, promoting trade liberalization and foreign direct investment in the agricultural sector could help alleviate domestic food price inflation, emphasizing the importance of reducing customary trade barriers to encourage investment and trade openness.

This paper aims to propose a laser micro-machined 4 × 4 elements microstrip array antenna suitable for 5 G millimeter wave (mm-wave) applications. Each patch element of the array is excited with same amplitude and phase that is achieved with proper novel impedance matching stub. The proposed antenna achieves a simulated gain of 13.15 dBi and a measured return loss of −24.80 dB at 28.73 GHz with a total bandwidth of 7.48 GHz. The designed antenna is directional with a directivity of 15.1 dBi at 28.73 GHz, whereas fabricated on a low cost FR4 substrate with a substrate thickness of 0.074 λ mm. The antenna is realized with an aperture size of 2.24λ × 3.26λ.

The antenna structure starts from the design of single element called unit cell. The single element is designed using the transmission line model equations of a rectangular patch. To design a 28 GHz microstrip patch antenna, a dielectric material with lower permittivity and having thickness (h) less than 1 mm is required. This specification gives better gain and efficiency by reducing surface waves and mutual coupling between elements. The inset width is optimized to achieve the minimum reflection coefficient (S11). The single element has been arranged with a minimum spacing of λ/2 (5.3571 mm) in an H plane and E plane. It is connected using the microstrip lines with proper impedance matching. The four 2 × 2-sub array cell subsystems are connected with a corporate feed together formed the 4 × 4-array cell. Rectangular planar array method is used to arrange the elements in the 4 × 4 array cell.

The design concept is simple which includes the combination of corporate feed and insect feed. It is compact in size and easy to fabricate. The bandwidth of fabricated prototype antenna array is achieved as 7.48 GHz from 24.98 GHz to 32.46 GHz. The mutual coupling is very less though the antenna array is placed with minimum spacing between adjacent elements. This is because of the microstrip feeding structure with minimum phase shift. The gain can be further enhanced with increasing number of array element and proper designing of feed line. Owing to the advantages of low profile, wide bandwidth and high gain, the designed array will be potentially useful in 5 G wireless communications.

The measured antenna offers bandwidth 7.48 GHz (24.98 GHz-32.46 GHz) with centered frequency 28.73 GHz. The agreement between simulated and measured results is good. The VSWR is observed 0.32 < 2, offers good impedance matching and low mutual coupling. It gives better E-Field and H-field radiation patterns of the 4 × 4 array antenna structure at 28 GHz. The total gain of 13.14 dBi is achieved at the center frequency. The total efficiency of 63.42 per cent is achieved with FR4 substrate.

To investigate the mechanical properties of geopolymer concrete at elevated temperatures.

The investigation involved studying the influence of partially replacing fly ash with ground granulated blast furnace slag (GGBS) at different proportions (5%, 10%, 15%, 20% and 25%) on the composition of the geopolymer. This approach aimed to examine how the addition of GGBS impacts the properties of the geopolymer material. The chemical NaOH was purchased from the local supplier of Jamshedpur. The alkali solution was prepared with a concentration of 12 M NaOH to produce the concrete. After several trials, the alkaline-to-binder ratio was determined to be 0.43.

The compressive strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 35.42 MPa, 41.26 MPa, 44.79 MPa, 50.51 MPa and 46.33 MPa, respectively. The flexural strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 5.31 MPa, 5.64 MPa, 6.12 MPa, 7.15 MPa and 6.48 MPa, respectively. The split tensile strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 2.82 MPa, 2.95 MPa, 3.14 MPa, 3.52 MPa and 3.31 MPa, respectively.

This approach allows for the examination of how the addition of GGBS affects the properties of the geopolymer material. Four different temperature levels were chosen for analysis: 100 °C, 300 °C, 500 °C and 700 °C. By subjecting the geopolymer samples to these elevated temperatures, the study aimed to observe any changes in their mechanical.

The purpose of this paper is to improve the design of a solid square canopy of a parachute. The design improvements are brought out by providing minor slits in the canopy area. Proper designing of the parachute was carried out using theoretical investigation coupled with experimentation. This parachute is designed for launch of sonobuoy from fixed wing aircraft.

Literature review was carried out on the design of such parachutes for the launch of a sonobuoy from a high altitude to the water entry. Computational fluid dynamics (CFD) analysis provided the value of the coefficient of drag for the slit-cut square canopy parachute, with and without sonobuoy for different lengths of the slit. Besides the theoretical investigation, experimentation was also carried out to validate the design.

The experimentation was carried out on 58 and 75 gsm fabric canopies with the slit edge plain-cut with thermally sealed edges, stitched and strengthened. In the case of plain-cut slits on the canopy made of 75 gsm fabric, no tearing of the slit edge was observed in dynamic and flight tests.

The present work has been carried out considering various assumptions and limited trial data specific to precision drop of 9 kg payload. The work can be adopted for bigger parachute for dropping of higher payloads.

Lab strength test, track dynamic and flight trials were conducted to acquire useful data for the present analysis. Besides the theoretical investigations and CFD analysis inherently based on numerous assumptions, experimentation was carried out as the sonobuoy deployment conditions are full of uncertainty. Dynamic and airdrop tests were conducted for this reason to determine design changes in the slits, both at the material level and on improvisations.

Due to unceasing declination in environment, sustainable agro-food supply chains have become a topic of concern to business, government organizations and customers. The purpose of this study is to examine a problem associated with sustainable network design in context of Indian agro-food grain supply chain.

A mixed integer nonlinear programming (MINLP) model is suggested to apprehend the major complications related with two-echelon food grain supply chain along with sustainability aspects (carbon emissions). Genetic algorithm (GA) and quantum-based genetic algorithm (Q-GA), two meta-heuristic algorithms and LINGO 18 (traditional approach) are employed to establish the vehicle allocation and selection of orders set.

The model minimizes the total transportation cost and carbon emission tax in gathering food grains from farmers to the hubs and later to the selected demand points (warehouses). The simulated data are adopted to test and validate the suggested model. The computational experiments concede that the performance of LINGO is superior than meta-heuristic algorithms (GA and Q-GA) in terms of solution obtained, but there is trade-off with respect to computational time.

In literature, inadequate study has been perceived on defining environmental sustainable issues connected with agro-food supply chain from farmer to final distribution centers. A MINLP model has been formulated as practical scenario for central part of India that captures all the major complexities to make the system more efficient. This study is regulated to agro-food Indian industries.

The suggested network design problem is an innovative approach to design distribution systems from farmers to the hubs and later to the selected warehouses. This study considerably assists the organizations to design their distribution network more efficiently.

India launched Smart City Mission in 2015 with an objective of development of 100 smart cities with a completion deadline in 2019 that was extended till June 2023. Smart City Mission is an important mission in the backdrop that urban population in India is projected to be 67.55 crore in 2035 from 48.30 crore in 2020. Further, by 2035, the percentage of population in India at mid-year residing in ‘urban area’ will be 43.2% as per the United Nations – Habitat's World Cities Report 2022 and it will be just next to China's urban population in 2035 that is projected at 1.05 billion. A recent World Bank report (2022) estimated that India will need to invest US (United States) $840 billion over the next 15 years, i.e. US $55 billion per annum – into urban infrastructure if it has to effectively meet the needs of its fast-growing urban population.

This chapter focuses on financing of sustainable smart cities in India. This chapter summarises financing options explored by the government in the beginning, challenges faced in financing of Smart City Mission in India over a period due to various developments such as pandemic, delay in execution of projects under the Smart City Mission, among others. Finally, suggestions have been given for making financing means effective and sustainable. These suggestions are based on the gaps between the ‘financing means thought of’ in the beginning and ‘financing means actually applied’ while executing Smart City Mission in India. Financing part is worth exploring in the background that India had the fiscal deficit at 3.9% of Gross Domestic Product (GDP) in 2015–2016 and most recently, the country had the fiscal deficit at 6.71% of GDP in FY22. And the country also dealt with the pandemic like other economies and provided COVID-19 vaccine free of cost to all citizens. Insights are useful for any other economy with a similar sustainable and smart city mission while facing resource constraints.

The discourse traverses the intricate landscape of the metaverse, exploring its evolution, intricacies, and the symbiotic integration of artificial intelligence (AI). The metaverse, a virtual realm where individuals interact with digital entities, burgeons from a decades-old concept to a contemporary reality, captivating attention with its immersive potential. The union of AI and the metaverse heralds unprecedented possibilities and challenges. It fuels personalized recommendations, realistic avatars, intelligent Non-Playable Character (NPCs), and predictive analytics. However, concerns loom, spanning addiction, privacy, and security, as users immerse themselves in virtual realms, potentially neglecting real-world responsibilities and sharing sensitive information has been discussed in this chapter. The narrative further delves into the metaverse's anatomy, delineating its infrastructure, hardware, software, content creation, and commerce. The integration of AI into metaverse security epitomizes a confluence of innovation and growth. Balancing the potential benefits and risks, stakeholders embark on a journey toward a secure, immersive digital realm. The discourse advocates for proactive and responsible AI usage, encompassing transparency, accountability, and trustworthiness. Regulatory frameworks and standards emerge as essential guardrails, protecting user privacy and forestalling AI misuse.

This paper aims to examine how lack of financial cooperation damages the operational efficiency of supply chains. The thesis is that economic and technological forces are provoking increasing financial tensions that push companies to transfer their credit needs and inventory requirements to their weakest suppliers. Thus, what might initially seem positive from an individual perspective can in fact generate losses in production efficiency for the supply chain as a whole.

This paper uses official data collected from 116 first- and second-tier suppliers in the Spanish automotive components sector, covering nine years (2001-2009). The relationships between the key variables are analysed using panel data estimations.

Significant differences were found between the working capital (WC) of first- and second-tier companies, proving additionally that although this approach may temporarily improve the results of first-tier suppliers, it leads to lower production efficiency in plants throughout the value chain.

Practitioners should avoid short-sighted attitudes when organizing the supply chain on a cooperative basis, going beyond the conventional wisdom on physical and information flows between original equipment manufacturers and their suppliers to reach upstream stages and embracing financial considerations.

The paper takes a novel approach to the issue of inter-organizational collaboration in the supply chain, aiming to go beyond conventional Lean Supply practices. From an empirical point of view, while much of the research on the topic utilizes key informant insights collected using psychometric data collection techniques, this study uses different financial proxies collected from secondary panel data.

Fertility aspirations shape family planning behavior of a couple. Desire to have certain number of children is linked with various micro- and macro-level factors such as individuals’ characteristics, sociocultural contexts and unconscious personal motivations. Fertility aspirations are an important component of fertility decision-making and a major predictor of childbearing. In India, Uttar Pradesh (UP) is the most populated state with historically high levels of fertility rates as compared to national average. This research is a qualitative exploration of the perspectives and practices of women with respect to their fertility aspirations and family planning behavior in an urban setting. A cross-sectional study was conducted between August 2017 and July 2018 among married women and men of the reproductive age group of 17–49 years using qualitative methods. The study was done in Pakbara, a Census Town (has a minimum population of 5,000) in the district of Moradabad, situated in western UP. It was found that along with personal motivations of having a quality life change in objective circumstances has led to changes in the fertility aspirations of the participants, particularly women. Increasing education, more mobility in public spaces, aspirations for a quality life, exposure to mass media and new job opportunities generate revision of parental aspirations. Couples, particularly from middle and upper-middle classes, limit their family size to attain upward social mobility. Couples from lower economic class have realized that rise of household income has not been commensurate with rise in prices. Thus, restricted childbearing is one way to cope with the situation.