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This study aims to investigate the prevalence of shock boundary layer interaction (SBLI) in air-breathing intake system is highly undesirable since this leads to high pressure gradients, typical stream mutilation and pressure drop. A novel flow control mechanism is incorporated in this research holding an array configuration of passive flow control device (micro ramps [MR]) that is adapted to improve the boundary layer stability.

Two geometric variants of the MR, namely, MR40 and MR80 is considered which reduce the pressure drop during SBLI. The incidence oblique shock wave angle of 34° is considered for the modelling. Large eddy simulation (LES) turbulence model was used with subgrid models of Wall modelled LES, Smagorinsky–Lilly to compute the unsteady effects of SBLI control using micro vortex generators. The unsteady results are compared with steady Reynold’s average Naviers–Stoke’s equation for calibrating the turbulence models.

The array configuration of MR80 reduces the pressure drop by 22% as compared with no ramp configuration and also reduces the flow distortion in hypersonic inlet. The most affected region of the MR is in the vicinity of center-line. Quantitative results prove that the upstream influence of the shock waves has been largely reduces by MR80 array configuration as compared to single MR80 pattern configuration. Different vortex structures found in the experiments was exclusively predicted using LES.

This paper substantiates the requirement of MR array configuration for transferring the momentum from free stream to the boundary layer and thereby energizing the boundary layer. This process of energization delays the flow separation in hypersonic flow.

The purpose of this paper is to investigate effects of layer thickness on densification, surface morphology, microstructure and mechanical and corrosion properties of 420 stainless steel fabricated by laser-powder bed fusion (L-PBF).

Standard specimens were printed at layer thickness of 10, 20 and 30 µm to characterize Archimedes density, surface roughness, tensile strength, elongation, hardness, microstructural phases and corrosion performance in the as-printed and heat-treated condition.

Archimedes density slightly increased from 7.67 ± 0.02 to 7.70 ± 0.02g/cm³ and notably decreased to 7.35 ± 0.05 g/cm³ as the layer thickness was changed from 20 µm to 10 and 30 µm, respectively. The sensitivity to layer thickness variation was also evident in properties, the ultimate tensile strength of as-printed parts increased from 1050 ± 25 MPa to 1130 ± 35 MPa and decreased to 760 ± 35 MPa, elongation increased from 2.5 ± 0.2% to 2.8 ± 0.3% and decreased to 1.5 ± 0.2, and hardness increased from 55 ± 1 HRC to 57 ± 1 HRC and decreased to 51 ± 1 HRC, respectively. Following heat treatment, the ultimate tensile strength and elongation improved but the general trends of effects of layer thickness remained the same.

Properties obtained by L-PBF are superior to reported properties of 420 stainless steel fabricated by metal injection molding and comparable to wrought properties.

This study successfully the sensitivity of mechanical and corrosion properties of the as-printed and heat-treated parts to not only physical density but also microstructure (martensite content and tempering), as a result of changing the layer thickness. This manuscript also demonstrates porosity evolution as a combination of reduced energy flux and lower packing density for parts processed at an increasing layer thickness.

The COVID-19 has affected millions of people across the world and worsened the socio-economic conditions that have sound reasons to discuss about the impact of COVID-19 on the progress of achieving the target level of sustainable development. The stagflation due to COVID-19 has a possibility to push a large section of population back under the critical level of income. The economic restriction and lockdown has impacted on the supply of food and essential requirements for decent living. The health services and education have been jeopardised. So the possible impact to achieving the Sustainable Development Goals of no poverty (SDG1), zero hunger (SDG2), good health and wellbeing (SDG3), education (SDG4), decent work and economic growth (SDG8), income inequality (SDG10) are examined in this chapter. This chapter also discusses about the proper implementation and stress on SDGs as the possible instruments on the way out of recession. Difference-in-difference analysis is used to explain the impact of COVID-19 with the data in global context in respect of before COVID and after COVID.

Different pollutants emission due to the conventional energy consumption process is of major concern owed to its significant effect on human health vis-à-vis regional climate. The purpose of this paper is to develop mitigation strategies to reduce the pollutant concentrations in the rural households conducted in a pristine rural village of Indian Sunderban area.

During winter, 2014, 20 households which were using traditional biomass cookstove for cooking and kerosene-lamp for lighting (KIT-TRD) were randomly selected. Specific type of improved forced draft biomass cookstove and solar lantern were used in ten of the selected households (KIT-IMP). Real time concentrations of particulate matter (PM) (PM_2.5, PM₁₀) and carbon monoxide (CO) during day and evening time cooking period were measured in KIT-IMP and KIT-TRD. A simulation model was established to evaluate most potential factor to control the level of pollutants inside the kitchen.

Conventional processes of energy consumption in the households, along with the outdoor concentration of pollutants influence the indoor concentration of measured pollutants. The concentration of PM and CO was significantly lower in the KIT-IMP than the other. In the KIT-TRD households, the daytime concentration of PM and CO was significantly higher compared to the evening. The simulated output overestimated the concentration of PM10 and CO in the KIT-TRD.

The concentration of PM_2.5, PM₁₀ and CO significantly reduces in the indoor environment with the introduction of improved cookstove and solar lantern; however, further research is required to develop optimum sizes of window and door in the rural households to reduce the concentrations of different pollutants inside the kitchen.

This article documents instances of racism that have previously acted as barriers to Indian students' academic success in Australia. It is felt that such incidents would not have happened to students from, for example, China or Japan, as their governments would have taken more serious steps against the Australian government. There is a feeling in India that the Indian government can be seen as weak. Against this background, the article looks at potential reasons for racially motivated attacks against Indians in Australia, and at what can be done to reduce these, as well as both the Australian and Indian government responses to the particular instances reported.

The purpose of this paper is to identify and evaluate the relationships among the flexibility enablers and to prepare a hierarchy of these enablers to know their influences over each other in global supply chain. The framework suggests that the priority of enablers in supply chain should be determined on the basis of their driving power and dependency.

Various enablers used by researchers and practitioners for flexibility management of global supply chain have been identified. These enablers have been classified as strategic, operational and performance‐based enablers. Interpretive structural modeling (ISM) is used to establish mutual relationships among the flexibility enablers and to prepare a hierarchy‐based model.

It has been observed that some enablers having high‐driving power and low dependency are of strategic importance. These enablers require more attention while other enablers based on operations and performances are dependents of strategic enablers.

The index of enablers based on driving power and dependency provides an insight to supply chain managers to make the entire supply chain highly flexible and help them to respond to global uncertainties.

Presentation of enablers in the form of hierarchy using ISM and ranking them into various driving power and dependent categories is a good effort to make flexible global supply chain.

Kolkata Port (KoPT) had achieved a turnaround from having made a loss of Rs 7.5 crores (cr) in the year 2000–01 to a net surplus of Rs 465.1 cr in the year 2006–07. A variety of initiatives had been taken during the intervening years with a focus on tariff rationalization, revenues from alternate sources, infrastructure development and productivity improvements. While these had yielded results, there was a fundamental issue of operational complexity and inability to compete due to the locational disadvantage. KoPT was a riverine port with two locations, 232 kms and 115 kms upstream on the Hooghly with draft limitations.

Two significant studies having implications for future strategies of KoPT had recently been submitted in March and November 2007. The top management of the port, including the Chairman who was responsible for driving many of the initiatives, was concerned that it may not be possible to achieve long term sustainable growth continuing with the strategies used so far. A well thought out future roadmap, breaking away from the present thinking, was essential sustained growth.

The study aims to examine the role of health-care supply chain management during the COVID-19 pandemic in a cross-section of 42 selected sub-Saharan African (SSA) countries.

The study used cross-sectional robust least square regression for parameter estimates.

The results confirmed the N-shaped relationship between the health-care logistics performance index (HLPI) and COVID-19 cases. It implies that initially HLPI increases along with an increase in COVID-19 cases. Later down, it decreases COVID-19 cases by providing continued access to medical devices and personal protective equipment. Again, it increases due to resuming economic activities across countries.

The continuing health-care supply chain is crucial to minimize COVID-19 cases. The international support from the developed world in providing health-care equipment, debt resettlement and resolving regional conflicts is deemed desirable to escape the SSA countries from the COVID-19 pandemic.

The importance of the health-care supply chain during the COVID-19 pandemic is evident in the forecasting estimates, which shows that from August 2021 to April 2022, increasing the health-care supply chain at their third-degree level would reduce coronavirus registered cases. The results conclude that SSA countries required more efforts to contain coronavirus cases by thrice increasing their health-care logistics supply chain.

This study aims to find a new alternate source for biodiesel conversion. The alternate source must be easily available, and it should give more oil yield than available edible, inedible sources. To meet the fuel demand in the transportation sector with edible oil-based biodiesel causes food versus fuel crisis. In addition to this, it increases NO_x and CO₂ in the environment.

The present paper reviews the comparison of algae oil yield, fatty acid composition and its biodiesel properties’ effect on diesel engine characteristics.

Algae were the only source to fulfil fuel demand because its oil and biodiesel yield is higher than other sources. Algae can grow by capturing carbon dioxide from the environment, and its fatty acid composition is more suitable to run diesel engines.

There is an improvement in engine performance–emission tradeoff with algal biodiesel.

The aim of this study is to determine the relationship between social media and libraries in terms of marketing. The present research is to find out the factors and impact as well as the issues related to libraries and marketing using social media. This study will give massive information regarding social media use for the marketing of library sources and services.

This study so far has been taken into account to review all the related literature of social media and library marketing. All the related literature studies were reviewed according to the suggested objectives of the study.

The present study reveals after reviewing literature that there is a great impact of social media on libraries. The literature shows that social media is the biggest change in the twenty-firstst century for library professionals and librarians. The reviewed literature studies have discovered that the libraries are facing too many challenges and issues to the adoption of social media for the marketing of library sources and services. The collected and analyzed works of the literature indicated that social media would be the best tool to promote library sources and services.

This research or study can serve the LIS professionals and librarians in the field of library and information science and librarianships that they are looking for the adoption and application of social media in the marketing of library sources and services to the targeted customers.

This research or study can serve the LIS professionals and Librarians in the field of library and information science and librarianships that they are looking for the adoption and application of social media in the marketing of library sources and services to the targeted customers.

To the best of the authors’ knowledge, this study is one of the first among those researches that is to disclose the close relationship between social media and libraries in terms of marketing of library sources and services.