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AbstractThis paper introduces a new method for developing Autoclaved Aerated Concrete (AAC) blocks, investigating the impact of different loading rates on compressive strength and failure behaviour. Alkaline solution and accelerated curing tank curing were explored as alternatives to conventional methods using aluminium powder and autoclave curing with fly ash. Construction and demolition waste was used as a substitute for fly ash, and chopped steel wool fibres were added to enhance block strength. The blocks were tested under various loading rates, and stress–strain graphs were generated to calculate Young’s modulus of elasticity values. ANSYS software was used for simulation and comparison, validating the accuracy of analytical models. The study shows a correlation between experimental and simulated values, confirming the successful incorporation of CDW and CSWF in AAC block development. Increasing the loading rate during testing leads to lower measured Young’s modulus, indicating strain rate dependency. However, including CSWF enhances Young’s modulus by redistributing stress and restraining crack propagation. The research contributes to understanding AAC's mechanical properties and performance, supporting its potential as a sustainable alternative for masonry materials in structural applications.

This study conducts a comparative analysis of linear regression (LR), multiple polynomial regression (MPR), and artificial neural network (ANN) to predict the compressive strength of sustainable geopolymer concrete (GPC). The prediction is made based on the experimental investigation that involves a mix design approach for the production of geopolymer concrete (GPC) using different proportions of industrial by-products, namely fly ash (FA) and ground granulated blast slag (GGBS) while taking into account various influential factors. The variables under consideration incorporate the proportions of FA and GGBS, the concentrations of sodium hydroxide (NaOH) solution (10 M, 12 M, and 14 M), the curing temperatures (65 ℃ and 80 ℃), and the age of the concrete specimen. The fresh and mechanical properties of each GPC mix are observed after each curing age. A scanning electron microscope (SEM) is used to investigate the microstructure of GPC by identifying different constituents of concrete (C-S–H, N-(C)-A-S–H). Experimental results demonstrate that the workability of all GPC mixes falls within acceptable limits. Notably, the FA100GGBS400 mix achieves the highest compressive strength (C-S) when activated with 14 M NaOH and cured at 80 ℃, and the SEM analysis also confirms it. The predictive outcomes indicate that the MPR model establishes the most robust relationship between input and output variables, exhibiting a coefficient of determination (R2) value of 0.99. These findings highlight the potential of the MPR model for accurately forecasting the compressive strength of sustainable geopolymer concrete, offering practical applications in the construction industry.

AbstractObjective:To identify urinary catheter (UC)–associated urinary tract infection (CAUTI) incidence and risk factors.Design:A prospective cohort study.Setting:The study was conducted across 623 ICUs of 224 hospitals in 114 cities in 37 African, Asian, Eastern European, Latin American, and Middle Eastern countries.Participants:The study included 169,036 patients, hospitalized for 1,166,593 patient days.Methods:Data collection took place from January 1, 2014, to February 12, 2022. We identified CAUTI rates per 1,000 UC days and UC device utilization (DU) ratios stratified by country, by ICU type, by facility ownership type, by World Bank country classification by income level, and by UC type. To estimate CAUTI risk factors, we analyzed 11 variables using multiple logistic regression.Results:Participant patients acquired 2,010 CAUTIs. The pooled CAUTI rate was 2.83 per 1,000 UC days. The highest CAUTI rate was associated with the use of suprapubic catheters (3.93 CAUTIs per 1,000 UC days); with patients hospitalized in Eastern Europe (14.03) and in Asia (6.28); with patients hospitalized in trauma (7.97), neurologic (6.28), and neurosurgical ICUs (4.95); with patients hospitalized in lower–middle-income countries (3.05); and with patients in public hospitals (5.89).The following variables were independently associated with CAUTI: Age (adjusted odds ratio [aOR], 1.01; P< .0001), female sex (aOR, 1.39; P< .0001), length of stay (LOS) before CAUTI-acquisition (aOR, 1.05; P< .0001), UC DU ratio (aOR, 1.09; P< .0001), public facilities (aOR, 2.24; P< .0001), and neurologic ICUs (aOR, 11.49; P< .0001).Conclusions:CAUTI rates are higher in patients with suprapubic catheters, in middle-income countries, in public hospitals, in trauma and neurologic ICUs, and in Eastern European and Asian facilities.Based on findings regarding risk factors for CAUTI, focus on reducing LOS and UC utilization is warranted, as well as implementing evidence-based CAUTI-prevention recommendations.

Simulation-based software testing supports engineers in finding faults in Simulink® models. It typically relies on search algorithms that iteratively generate test inputs used to exercise models in simulation to detect design errors. While simulation-based software testing techniques are effective in many practical scenarios, they are typically not fully integrated within the Simulink environment and require additional manual effort. Many techniques require engineers to specify requirements using logical languages that are neither intuitive nor fully supported by Simulink, thereby limiting their adoption in industry. This work presents HECATE, a testing approach for Simulink models using Test Sequence and Test Assessment blocks from Simulink® Test™. Unlike existing testing techniques, HECATE uses information from Simulink models to guide the search-based exploration. Specifically, HECATE relies on information provided by the Test Sequence and Test Assessment blocks to guide the search procedure. Across a benchmark of $18$18 Simulink models from different domains and industries, our comparison of HECATE with the state-of-the-art testing tool S-Taliro indicates that HECATE is both more effective (more failure-revealing test cases) and efficient (less iterations and computational time) than S-Taliro for $\approx$≈94% and $\approx$≈83% of benchmark models respectively. Furthermore, HECATE successfully generated a failure-revealing test case for a representative case study from the automotive domain demonstrating its practical usefulness.

Climate change poses an existential threat to humanity. It is now indisputable that the primary cause of this threat is human activity resulting in high greenhouse gas (GHG) emissions, which began during the Industrial Revolution and have continued to rapidly accelerate. The first warnings of impending and irreversible climate change were sounded decades ago, when governmental and intergovernmental policy makers had sufficient time to enact the changes needed to avoid the dire situation we find ourselves in today.

This study presents a comprehensive analysis of the development of aerated concrete (AC) blocks with a focus on the effect of various binders and additives on their mechanical and durability properties. The binders are flyash (FA), glass powder (GLP), and ground granulated blast furnace slag (GGBS). Further, cement, lime, gypsum powder, FA, GLP and GGBS were used as the individual binders in the absence of aluminium powder. Alternately, Na2SiO3and NaOH were combined in a ratio of (Na2SiO3/NaOH = 1.5) to produce the alkaline solution utilised in the design of AC blocks. Using an accelerated curing tank, heat curing was performed. Further substitution of FA or GLP and GGBS with 50% construction & demolition waste (C&D) waste was conducted in distinct batches. Later, 4% aluminium stearate powder (ASP) and 5% chopped steel wool fibres (CSWF) by weight were added to the various batches to create AC blocks and evaluate the effect on aeration and strength enhancement. Moreover, the mechanical and durability characteristics of each batch were analysed and compared. It was discovered that the mechanical and durability properties of GGBS-based mixtures were superior. ASP was also found to increase mechanical strength and resistance to chemical attack, while decreasing block density, water absorption, and drying shrinkage. The mechanical strength increased significantly as a result of CSWF influence on the batches. Eventually, a microstructural investigation of FA and GGBS-based AC blocks with and without ASP was conducted in order to interpret the differences that aluminium stearate causes in the morphology of aerated blocks.

AbstractThe employment in construction industry is large, highly diverse and versatile in nature. There is a need of sustainable Human Resource Management (HRM) practices in this sector, to achieve a balanced growth in terms of profitability, project efficiency and long-term client satisfaction. The main objective of the study is to formulate antecedents of sustainable human resource management practices in construction industry and develop the dimensions of sustainable HRM in construction. The findings of the study reveal critical sustainable HRM practices needed in construction organisations. The study results also indicate that Sustainable HRM practices, Corporate Social Responsibility (CSR) and Organisation’s financial performance are strongly correlated to each other. This study based on the results proposes a framework of sustainable HRM practices for construction organizations. Implementation of it would guide them to effectively plan and implement such policies that retain and attract high potential talent as important internal stakeholders and also help them to manage their CSR policies and financial objectives in a balanced way.

AbstractThe shear performance of concrete beams produced from construction and demolition (C&D) waste is evaluated by considering two different shear-span to depth ratios (a/d). A total of twelve beams are cast, in which four beams of natural aggregate concrete (NAC) of conventional mix-design procedure (denoted as NAC), four beams of recycled aggregate concrete (RAC) of identical mortar volume (IMV) mix-design procedure in conjunction with normal mixing procedure (NMP) (denoted as RAC/NMP), and rest four beams of RAC of IMV mix-design procedure in conjunction with proposed dual-stage mixing procedure (DSMPSiC) (symbolized as RAC/DSMPSiC). Out of four beams of each of the above categories, two beams are tested by considering a/d = 2.5 and the other two are tested by considering a/d = 3. The load-deflection curve, ultimate load carrying capacity, and crack propagation parameters are also evaluated. The results are compared with different empirical relations proposed in codes and published literature. Analysing critically, it is observed that the shear strengths of RAC/NMP beams are reduced by 19% for a/d = 2.5 and 13.5% for a/d = 3 as compared to corresponding NAC beams. However, after following the proposed DSMPSiC, the above reduction percentages are reduced by 11.2% and 5.2%, respectively.

The study aims to understand the dynamic impact of economic policy uncertainty on the cash holdings patterns of construction firms in India. A dynamic panel regression model was created with cash to total assets as the dependent variable and the policy uncertainty, natural log transformation of total assets as a proxy of size, natural log transformation of dividends, price to book value ratio in times as a proxy of growth opportunities, Indian promoter holding in percentage as a proxy of ownership, debt-equity ratio in times as a measure of leverage, return on total assets in percentage as a measure of profitability and change in sales as a measure of volatility as independent variables. Further, the data was split into two study periods (2003-2011 and 2012-2020) for a detailed investigation of the dynamic relationship between policy uncertainty and firm-level cash holding. The findings suggest that policy uncertainty and its lag, cash holding lag are the prominent drivers of cash holdings for Indian construction firms.

Respiratory syncytial virus (RSV) has been identified as a leading cause of lower respiratory tract infections in young children and elderly. Limited data are available on the clinical profile and outcome in neonates from India. We describe clinical profile and outcome data of neonates infected with RSV. A total of 14 neonates with acute respiratory illness (ARI) requiring newborn intensive care unit (NICU) admission were tested for respiratory virus infection. All 14 (100%) tested positive for RSV-A infection. Of these positive cases, 11 (78.57%) were NICU graduates. Cough, cold, and respiratory distress was observed to be the chief complain in 13 (92.85%) neonates. All except 2 required respiratory support. Total duration of respiratory support and hospital stay was 7 (3-12) and 8 (5-14) days, respectively. All the RSV-infected patients showed complete recovery. We observed that predominantly NICU graduates were susceptible to RSV illness with a slight male preponderance. Amongst infected, majority presented with ARI requiring respiratory support. The severity was more in NICU graduates who were born very preterm.

Ventilator associated pneumonia (VAP) occurring in the intensive care unit (ICU) are common, costly, and potentially lethal.

Ultrafast lasers reaching extremely high powers within short fractions of time enable a plethora of applications. They grant advanced material processing capabilities, are effective drivers for secondary photon and particle sources, and reveal extreme light-matter interactions. They also supply platforms for compact accelerator technologies, with great application prospects for tumor therapy or medical diagnostics. Many of these scientific cases benefit from sources with higher average and peak powers. Following mode-locked dye and titanium-doped sapphire lasers, broadband optical parametric amplifiers have emerged as high peak- and average power ultrashort pulse lasers. A much more power-efficient alternative is provided by direct post-compression of high-power diode-pumped ytterbium lasers—a route that advanced to another level with the invention of a novel spectral broadening approach, the multi-pass cell technique. The method has enabled benchmark results yielding sub-50-fs pules at average powers exceeding 1 kW, has facilitated femtosecond post-compression at pulse energies above 100 mJ with large compression ratios, and supports picosecond to few-cycle pulses with compact setups. The striking progress of the technique in the past five years puts light sources with tens to hundreds of TW peak and multiple kW of average power in sight—an entirely new parameter regime for ultrafast lasers. In this review, we introduce the underlying concepts and give brief guidelines for multi-pass cell design and implementation. We then present an overview of the achieved performances with both bulk and gas-filled multi-pass cells. Moreover, we discuss prospective advances enabled by this method, in particular including opportunities for applications demanding ultrahigh peak-power, high repetition rate lasers such as plasma accelerators and laser-driven extreme ultraviolet sources.

In view of the complexity of the environment today, there is a need to reassess the leadership skills desired from modern managers, as relying on usual leadership development theories may not be enough. Exploring leadership principles from the age old, time-tested Indian values might prove to be an important solution. The present study attempts to identify a newer leadership development way through ancient Indian values of Bhagvad Gita for addressing leadership challenges in front of today's managers. It adds to the earlier works in this area by identifying and describing the most significant leadership skills based on principles of Bhagvad Gita for developing leadership competence of modern managers through 'hermeneutics' methodology and an empirical testing support. The main contribution of the study is the proposed leadership skills development framework which will add value to the current leadership development initiatives of the organisations and help developing leadership competencies in a sustainable way.

Due to the globalisation, large organisations in almost all sectors today have become multicultural and multidisciplinary. This calls for the need to identify and address the emerging barriers to cross-cultural communication which may hinder effective management of workforce. As the workforce is becoming increasingly global and culturally diverse, efficiency in interpersonal and intercultural communication is imperative for effective team performance and success. The objective of the paper is to identify the critical cross-cultural communication barriers (CCCB) in managing workforce diversity at multicultural organisations. The study also further examines the impact of these CCCBs on the team performance at multicultural organisations and based on the results, proposes a cross-cultural communication framework which could be adopted by multicultural organisations in India and all other countries where similar situations prevail.

Improper waste management is leading to heavy-metal contamination in domestic waste water, particularly in developing countries. This study examined the impacts of a 1:1 (w/w) mixture of nickel (Ni) and cobalt (Co) metal ions on reactor performance, metabolic activity and sludge biomass characteristics in sequential batch reactors (SBRs). The study also investigated the recovery potential of sludge biomass, when the metal ions were discontinued from the feed. Two sets of four identical SBRs labelled as RMix0 (control), RMix5, RMix25 and RMix75 were fed with a carbon (C) source and a mixture of nickel (II) + cobalt (II) metal ions in concentrations of 0, 5, 25 and 75 mg/l, respectively. The SBRs were operated with a cycle time of 12 h. The two phases consecutively investigated were the stressed phase (metals present in the feed) for 21 days and the recovery phase (metals absent in the feed) for 14 days. The results showed that during the stressed phase, chemical oxygen demand removal and metabolic activity in RMix25 and RMix75 deteriorated. Settling characteristics and biomass morphology underwent severe changes in RMix25 and RMix75. On the basis of the results, the study suggests monitoring the settling characteristics of biomass for early indication of metallic infiltration as a damage prevention strategy for sludge biomass in a waste-water-treatment plant.

Background: Short-term peripheral venous catheter–associated bloodstream infection rates have not been systematically studied in Asian countries, and data on peripheral venous catheter–associated bloodstream infections incidence by number of short-term peripheral venous catheter days are not available.Methods: Prospective, surveillance study on peripheral venous catheter–associated bloodstream infections conducted from 1 September 2013 to 31 May 2019 in 262 intensive care units, members of the International Nosocomial Infection Control Consortium, from 78 hospitals in 32 cities of 8 countries in the South-East Asia Region: China, India, Malaysia, Mongolia, Nepal, Philippines, Thailand, and Vietnam. For this research, we applied definition and criteria of the CDC NHSN, methodology of the INICC, and software named INICC Surveillance Online System.Results: We followed 83,295 intensive care unit patients for 369,371 bed-days and 376,492 peripheral venous catheter-days. We identified 999 peripheral venous catheter–associated bloodstream infections, amounting to a rate of 2.65/1000 peripheral venous catheter-days. Mortality in patients with peripheral venous catheter but without peripheral venous catheter–associated bloodstream infections was 4.53% and 12.21% in patients with peripheral venous catheter–associated bloodstream infections. The mean length of stay in patients with peripheral venous catheter but without peripheral venous catheter–associated bloodstream infections was 4.40 days and 7.11 days in patients with peripheral venous catheter and peripheral venous catheter–associated bloodstream infections. The microorganism profile showed 67.1% were Gram-negative bacteria: Escherichia coli(22.9%), Klebsiellaspp (10.7%), Pseudomonas aeruginosa(5.3%), Enterobacterspp. (4.5%), and others (23.7%). The predominant Gram-positive bacteria were Staphylococcus aureus(11.4%).Conclusions: Infection prevention programs must be implemented to reduce the incidence of peripheral venous catheter–associated bloodstream infections.

In the present scenario, solar-powered Lighter-Than-Air-Platforms (LTAPs) find wide applications in the field of surveillance, air monitoring, line of sight communication, mapping of the earth’s topography. Accordingly, there are specified power requirements for the sensors integrated on such systems. A helium-gas filled LTA system may be an airship or tactical aerostat with variable size depending on type of sensor array and payload units deployed onboard. Interestingly, power generated through lightweight and flexible photovoltaic panels show degradation tendency in the presence of impact factors such as dynamic cloud footprints, wind disturbances, and inherent platform contour leading to Non-Uniform Illumination. Thus, destabilization effects of these degradation factors, towards onboard harvested solar energy. Novelty lies in design for environmental factors such as clouds and winds for solar power computations onboard LTA systems. PV efficiency considering impact of wind velocity disturbances on contoured LTA platform is observed as 89.44 %. An efficiency drop of 22.06 % is reported under the prevailing cloud shadows on the Lighter Than Air system. This paper presents a novel systematic methodology to accurately compute the deficit energy under the prevailing conditions for Lighter Than Air systems.

Purpose: The purpose of this paper is to describe a participatory qualitative research project using the Delphi consensus technique aided by Internet technology for successful transition of academic endeavors during and the post COVID era. The study aimed to derive a holistic competency matrix for an optometry program for transformation of the program to competency-based education. Design/methodology/approach: This study combined a scoping review of literature for developing a baseline competency framework, along with derivation of an E-Delphi consensus within a panel of diverse stakeholders to achieve the objective of plotting a detailed competency matrix. Findings: The involvement of all stakeholders of educational system in Delphi study resulted in a valid and all-inclusive competency framework with 18 competency units and 97 competency elements. This framework provided a strong base for redesigning pedagogy and assessment methods during COVID-19 crisis. Practical implications: The paper highlights the feasibility and utility of adopting a participatory approach during COVID-19 outbreak. The Delphi technique aided by Internet technology was employed to develop a competency-based curriculum. Social implications: The paper narrates a suitable, feasible and scientific method for rapid transition in academia, following the restrictions and social distancing norms imposed during the COVID-19 outbreak. Originality/value: Although there is good evidence for use of the Delphi technique in curriculum development, this paper adds value by focusing on a participatory approach in using it. The suggested method here shows ways to gain optimum scientific output with minimum resources in constrained situations such as COVID-19 crisis.

AbstractBackground:Short-term peripheral venous catheter–related bloodstream infection (PVCR-BSI) rates have not been systematically studied in resource-limited countries, and data on their incidence by number of device days are not available.Methods:Prospective, surveillance study on PVCR-BSI conducted from September 1, 2013, to May 31, 2019, in 727 intensive care units (ICUs), by members of the International Nosocomial Infection Control Consortium (INICC), from 268 hospitals in 141 cities of 42 countries of Africa, the Americas, Eastern Mediterranean, Europe, South East Asia, and Western Pacific regions. For this research, we applied definition and criteria of the CDC NHSN, methodology of the INICC, and software named INICC Surveillance Online System.Results:We followed 149,609 ICU patients for 731,135 bed days and 743,508 short-term peripheral venous catheter (PVC) days. We identified 1,789 PVCR-BSIs for an overall rate of 2.41 per 1,000 PVC days. Mortality in patients with PVC but without PVCR-BSI was 6.67%, and mortality was 18% in patients with PVC and PVCR-BSI. The length of stay of patients with PVC but without PVCR-BSI was 4.83 days, and the length of stay was 9.85 days in patients with PVC and PVCR-BSI. Among these infections, the microorganism profile showed 58% gram-negative bacteria: Escherichia coli(16%), Klebsiellaspp (11%), Pseudomonas aeruginosa(6%), Enterobacterspp (4%), and others (20%) including Serratia marcescens. Staphylococcus aureuswere the predominant gram-positive bacteria (12%).Conclusions:PVCR-BSI rates in INICC ICUs were much higher than rates published from industrialized countries. Infection prevention programs must be implemented to reduce the incidence of PVCR-BSIs in resource-limited countries.

Heavy metals are frequently encountered in domestic wastewaters (sources being the usage of paints, batteries, electronic goods, etc.). It can get carried away by storm water through municipal sewer systems to the domestic wastewater treatment plants and affecting the biomass. The present work aims to study the impact of nickel [Ni(II)] ion on settling characteristics, metabolic activity and morphology of aerobic sludge biomass in sequential batch reactors (SBRs) in addition to reactor performance. Four SBRs, namely RNi0 (control), RNi5, RNi25 and RNi75, with different concentrations of Ni(II) (0, 5, 25 and 75 mg/L, respectively) in the feed are studied to investigate its impact on aerobic sludge biomass. Reactors are operated in a sequential batch mode with a cycle time of 12 h. At the start of the stressed phase of operation, i.e., the presence of Ni(II) in feed, the COD removal of reactors RNi25 and RNi75 is deteriorated to as low as 50 and 30%, respectively. Settling velocity and compactness of aerobic biomass in the reactors with Ni(II) in feed improved as compared to control. In the recovery phase of operations, when Ni(II) is absent in feed, the reactors show stable performance with nearly 80% COD removal for all the reactors. Notable changes are observed in aerobic biomass morphology and in biomass activity for all the reactors in stressed as well as recovery phases of operations. This study presents results of extensive investigation of aerobic sludge biomass subjected to stressed phase of operation with Ni(II) in the feed and subsequent recovery phase operation with feed without Ni(II).

Cyber-physical systems theory offers a powerful framework for modeling, analyzing, and designing real engineering systems integrating communication, control, and computation functionalities (the cyber part) within a natural and/or man-made system governed by the laws of physics (the physical part). New methodological developments in cyber-physical systems theory are required by traditional application domains such as manufacturing, transportation, and energy systems, which are currently experiencing significant and – to some extent – revolutionary changes to address the needs of our modern society. The goal of this position paper is to provide the cyber-physical systems community, and especially young researchers, a clear view on what are research directions worth pursuing motivated by the challenges posed by modern applications.

A proficient, microwave mediated methodology using CuFe2O4 nanoparticle as the catalyst for S-arylation of substituted benzene boronic acids with thiophenol has been developed. In this method, the substituted thioethers were easily obtained through a C-S bond formation using microwave irradiation technique as well as conventional heating in the presence of CuFe2O4 nanoparticles with modest to excellent yields with the less reaction time. The ligand free microwave technique helped in the preparation of substituted thioethers in measurable amount within 10 mins. The same results were obtained with conventional heating in 12h. The reported method is economically efficient and an alternative to the initial existing method for the preparation of substituted thioethers.

Infrastructure has been identified as the backbone of any economy as it provides channels of economic growth. For emerging economies like India, with 31% current urban population and contribution of 63% to GDP; the pie is expected to increase to approximately 40 percentages by 2031 with a GDP contribution of 70%-75%. This creates a need for rapid development as well as the strengthening of existing urban infrastructure to accommodate growing demand and to exploit its economic contribution. The extent of urban infrastructure development is delivered at three levels of governance; Centre, State and urban local bodies (ULBs). ULBs being the last level of governance for infrastructure development in urban India, they are grossly under-equipped to effectively generate revenues and raise capital. The present study has identified issues in the existing financing and assessment framework of ULBs and suggests a framework to rationalise their funding patterns and to bring competitiveness. The paper stresses the need of the proposed framework to bring smart city SPV and other ULBs at the equal platform.

E-government adoption has been the focus of many research studies in the past. However, few studies have explored the role of technology anxiety and information quality in the E-government adoption process. The purpose of this paper is to examine the direct and indirect effects of technology anxiety and information quality on E-government adoption. The results of our study indicate that technology anxiety indirectly influences E-government adoption. At the same time, the direct effect of technology anxiety on E-government adoption weakens in the presence of effort expectancy. Perceived information quality has positive direct effect on E-government adoption. However, we did not find any significant indirect effect of information quality on E-government adoption. This study contributes to E-government adoption frameworks by analysing the effect of computer and internet related anxiety and information quality on the adoption of E-government services. Implications for theory and practice that would help the policy makers in enhancing the effectiveness of E-government services have been discussed.

ABSTRACTThis essay discusses the phenomena of amalgamation of two prominent technologies: Internet of Things (IoT) and Social technologies. IoT devices are primarily used for connectivity between physical objects while Social technologies are responsible for collaboration and social interaction. The domain of Social Internet of Things (SIoTs) points toward social interactions of IoT devices. This phenomenon will further enhance the collaboration capabilities of IoTs to deliver huge amounts of human–computer interactions with very limited interventions from humans. Thus, high degrees of human–computer interfaces can be created among physical objects by enabling them with human-like capabilities and social interactions. In this context, we discuss relevant research developments, contextually analyze the drivers and challenges of SIoTs, and describe some interesting business use cases along with suitable recommendations going forward.

The quasi infinite horizon NMPC formulation developed by Chen and Allgöwer [1998] provides a systematic method to characterize the terminal set needed to ensure nominal stability of a system controlled using finite horizon NMPC formulation at an unstable operating point. Their approach, however, has been developed for continuous time NMPC formulations. Real time implementation of an NMPC scheme using microprocessors, however, makes model discretization inevitable. In this work, a discrete time version of the quasi infinite NMPC formulation is developed, which is particularly suited for operating a system at an unstable operating point. Also, a novel approach is developed for characterization of the terminal region that makes use of the discrete time nonlinear model and that provides sufficient degrees of freedom to characterize the terminal region. The nominal closed loop system is then shown to be equi-asymptotically stable when controlled using the proposed discrete time QIH-NMPC. Efficacy of the proposed approach is demonstrated using a benchmark problem given by Chen and Allgöwer [1998]. The simulation study shows that the terminal regions for the discrete time case are relatively smaller than the terminal region for the continuous time case reported by Chen and Allgöwer [1998]. Also, the proposed discrete time QIH-NMPC is able to steer the state trajectories from specified feasible initial conditions to locations inside the terminal set within the specified prediction horizon and later converge to the unstable operating point.

The web has evolved enormously in the past few years resulting in a rapid increase in the number of web users and web pages. Web personalisation has become a challenging task for e-commerce-based companies due to information overload on the web and increase in the number of web users. Recommendation systems generate recommendations to users for various products as per their requirements. Recommendation systems have been widely used in e-commerce websites and have become an integral part of the ecommerce business process. Developers try to customise websites to suit the needs of specific users utilising the knowledge acquired from users' navigational behaviour. The current study focuses on development of a framework for a web recommendation system on the basis of sequential information present in web logs. Rough set-based clustering using similarity upper approximation has been utilised to generate soft clusters to capture the multiple interests of users. The proposed recommendation system can predict the next possible page visit of the user based on the sequential information present in their navigation pattern.