Rajesh T.N., T.J. Sarvoththama Jothi and Jayachandran T.
The purpose of this paper is to estimate the chamber pressure and flow behaviour in a vortex thrust chamber (VTC) during the cold flow with hydrogen and oxygen as propellants.
Abstract
Purpose
The purpose of this paper is to estimate the chamber pressure and flow behaviour in a vortex thrust chamber (VTC) during the cold flow with hydrogen and oxygen as propellants.
Design/methodology/approach
Experiments are carried out in a VTC with a different mixture ratio of hydrogen and oxygen. The pressures developed inside the VTC are measured. Numerical simulations are carried out to understand the flow patterns of fuel and oxidizer inside the VTC.
Findings
The chamber pressure is influenced by the type of injection of propellant and mixture ratio. Tangential injection of propellant is the key parameter for an increase of the chamber pressure of the VTC.
Research limitations/implications
The pressure measurements are carried out in cold flow conditions without combustion happening in the VTC.
Practical implications
The practical implication is that when the combustion in the VTC ceases, the thrust generated due to the propellants in cold flow conditions can be assessed.
Originality/value
The VTC with the tangential injection of propellant generates higher chamber pressure.
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Emerging Economies (EEs) are characterized by sustained growth performance, but they suffer from inequality as well, especially the Gender Inequality. Literature points out a…
Abstract
Emerging Economies (EEs) are characterized by sustained growth performance, but they suffer from inequality as well, especially the Gender Inequality. Literature points out a number of gender norms which play a significant role in aggravating the gender disparity. The chapter chooses a panel of 25 EEs for the period of 2007–2020 to investigate how gender norms can affect the female labor force participation (FLFP) and development relationship. Results suggest that EEs are in a stage of development where even if countries are growing at a reasonable rate, FLFP is falling. Further investigation reveals that skewed sex ratio can dampen the impact of development, whereas secondary school enrollment and legislation to protect women from sexual harassment in the workplace may foster the effect of development. Thus, policies to encourage parents to invest more on the girl child and providing legal support to women at the workplace can be effective policies to reduce gender inequality.
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R.C. Mehta, M.J. Pandya and T. Jayachandran
Under‐ and over‐expanded jet flows are calculated for theEuler equations. The solution procedure is based on the two‐stageRunge‐Kutta time‐stepping scheme. The studies of the flow…
Abstract
Under‐ and over‐expanded jet flows are calculated for the Euler equations. The solution procedure is based on the two‐stage Runge‐Kutta time‐stepping scheme. The studies of the flow field structure in diffusers, free jets and impinging jets have been investigated for a range of jet‐to‐stream total pressure ratios and for different exit Mach numbers. The resulting flows show a complex shock‐shear expansion structure with Mach discs. Numerical results are compared with available experimental data and with previously published data. An oscillating phenomenon was observed in the case of free jets operating at sonic exit Mach number and in another case of impingement of under‐expanded jets on a flat plate.
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The economics literature on gender has expanded considerably in recent years, fueled in part by new sources of data, including from experimental studies of gender differences in…
Abstract
The economics literature on gender has expanded considerably in recent years, fueled in part by new sources of data, including from experimental studies of gender differences in preferences and other traits. At the same time, economists have been developing more realistic models of psychological and social influences on individual choices and the evolution of culture and social norms. Despite these innovations, much of the economics of gender has been left behind, and still employs a reductive framing in which gender gaps in economic outcomes are either due to discrimination or to “choice.” I suggest here that the persistence of this approach is due to several distinctive economic habits of mind – strong priors driven by market bias and gender essentialism, a perspective that views the default economic agent as male, and an oft-noted tendency to avoid complex problems in favor of those that can be modeled simply. I also suggest some paths forward.
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Jean‐Loup Chenot, E. Massoni and JL. Fourment
Focuses on the inverse problems arising from the simulation of forming processes. Considers two sets of problems: parameter identification and shape optimization. Both are solved…
Abstract
Focuses on the inverse problems arising from the simulation of forming processes. Considers two sets of problems: parameter identification and shape optimization. Both are solved using an optimization method for the minimization of a suitable objective function. The convergence and convergence rate of the method depend on the accuracy of the derivatives of this function. The sensitivity analysis is based on a discrete approach, e.g. the differentiation of the discrete problem equations. Describes the method for non‐linear, non‐steady‐state‐forming problems involving contact evolution. First, it is applied to the parameter identification and to the torsion test. It shows good convergence properties and proves to be very efficient for the identification of the material behaviour. Then, it is applied to the tool shape optimization in forging for a two‐step process. A few iterations of the inverse method make it possible to suggest a suitable shape for the preforming tools.
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Ashley Larsen Gibby, Tiffany Fox Okeke, Nancy Luke, Melissa Alcaraz and Mikaela Dufur
Much research has explored high levels of son preference in India, finding that parents often report a desire for more sons than daughters. While scholars have noted that a…
Abstract
Much research has explored high levels of son preference in India, finding that parents often report a desire for more sons than daughters. While scholars have noted that a nontrivial portion of respondents claim to have no sex preference, little is known about (1) the characteristics of this group and (2) how such parental preferences relate to child outcomes. We use data from a representative study of rural South Indian households (n = 7,891 adults) to address these gaps. Descriptive results show that a sizable portion of respondents – one in four – indicated that, at the start of their marriage, they had no preference for the number of daughters or sons they wanted. Further, multinomial regression results show that those who reported no sex preference at the time of marriage were more likely to be female, older, and less likely to be sterilized than those who reported equal or son preference, with additional distinctions across educational attainment and religion. Turning to child-level outcomes, we examined whether parents’ sex preferences related to adolescent mental health through ordinary least squares (OLS) regression models (n = 1,245 adolescents). Adolescents whose mothers stated no sex preference reported significantly fewer anxiety and depressive symptoms than their peers. Fathers’ sex preferences were not significantly related to adolescent mental health. These findings suggest that a lack of sex preference may hold meaningful and positive implications for adolescent mental health. Further, although son preference is a widespread phenomenon, singular attention on those with son preference may mask important nuances among Indian families.
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Bekinew Kitaw Dejene and Tsige Mamo Geletaw
The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green…
Abstract
Purpose
The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green synthesis and mechanism of ZnO nanoparticles, with prospective applications of zinc oxide nanoparticles (ZnO NPs) in self-cleaning textiles.
Design/methodology/approach
This review introduces a green mechanism for the synthesis of ZnO NPs using plant extracts, their self-cleaning properties and the mechanisms of physical, chemical and biological self-cleaning actions for textile applications.
Findings
ZnO NPs are among the several nanoparticles that are beneficial for self-cleaning textiles because of their exceptional physical and chemical properties, although review publications addressing the use of ZnO NPs in textiles for self-cleaning are uncommon. These results indicate that the plant-synthesized ZnO NPs display excellent biological, physical and chemical self-cleaning properties, the mechanism of which involves photocatalysis, surface roughness and interactions between ZnO NPs and bacterial surfaces.
Originality/value
Nanoformulations of plant-synthesized ZnO have been reviewed to achieve promising self-cleaning textile properties and have not been reviewed earlier.
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Adji Achmad Rinaldo Fernandes and Idrus Muhammad Taba
This paper aims to investigate the moderation effect of welding technology on the relationship between government policy and quality human resources and workforce competitiveness.
Abstract
Purpose
This paper aims to investigate the moderation effect of welding technology on the relationship between government policy and quality human resources and workforce competitiveness.
Design/methodology/approach
The research is quantitative in nature, i.e. it aims to explain the causality relationship between variables. This research is quantitative research, it aims to explain the causality relationship between variables. The analysis tool was generalized structure component analysis.
Findings
First, government policy has a significant and positive effect on workforce competitiveness, indicating that higher government policy will result in higher workforce competitiveness. Welding technology is the moderating variable in the relationship between government policy and workforce competitiveness. Higher implementation of welding technology will strengthen the relationship between government policy and workforce competitiveness. Second, quality of human resources has a significant and positive effect on workforce competitiveness; higher quality of human resources will therefore result in higher workforce competitiveness. Welding technology is the moderating variable in the relationship between quality of human resources and workforce competitiveness. Higher implementation of welding technology will therefore strengthen the relationship between quality of human resources and workforce competitiveness.
Originality/value
The moderating effect of welding technology in the relationships between government policy and quality of human resources and workforce competitiveness has not been comprehensively studied yet; the present study fills this gap.
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Xin Li, ZaiFu Cui, Daoheng Sun, Qinnan Chen, Gonghan He, Baolin Liu, Zhenyin Hai, Guochun Chen, Zhiyuan Jia and Zong Yao
The measurement of heat flux is of importance to the development of aerospace engine as basic physical quantities in extreme environment. Heat radiation is one of the basic forms…
Abstract
Purpose
The measurement of heat flux is of importance to the development of aerospace engine as basic physical quantities in extreme environment. Heat radiation is one of the basic forms of heat transfer phenomenon. The structure optimizing can improve the performance and infrared absorptivity of the thin film sensor.
Design/methodology/approach
This paper designed one kind of thin film heat flux sensor (HFS) with antireflective coating based on transparent conductive oxide thermopile. The introduced membrane structure is so thin that it has little impact on sensor performance. Fabrication of thin film sensors were fabricated by physical vapor deposition (PVD) process.
Findings
The steady-state and dynamic response characteristics of the HFS were investigated by calibration platform. The experimental results shown that the absorptivity of the membrane structure (for1070nm) improved compared with that before optimization. The sensitivity of heat flux gauge was 48.56 µV/ (kW/m2) and its frequency response was determined to be about 1980 Hz.
Originality/value
The thin film HFS uses thermopile based on Indium Tin Oxid and In2O3. The antireflective coating is introduced to hot endpoint of HFS to improve sensitivity on laser thermal source. The infrared optical properties of membrane layer structure were investigated. The steady-state and the transient response characteristics of the heat flux sensor were also investigated.
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Surendra Babu Ayenampudi, Riya Verma and Samuel Ayofemi Olalekan Adeyeye
Jamun is an underutilised fruit crop of India whose utilization needs to be considerably increased. Despite its impressive nutritional profile and several health benefits, its…
Abstract
Purpose
Jamun is an underutilised fruit crop of India whose utilization needs to be considerably increased. Despite its impressive nutritional profile and several health benefits, its cultivation is still very limited. Hence, this study aims to highlight the essential nutrients, health benefits and value-added products of jamun fruit and seed.
Design/methodology/approach
Major sources of bibliometric information such as Web of Science, Scopus, PubMed and Google Scholar were extensively searched with keywords such as nutritional composition of jamun, bioactive compounds, health benefits and jamun-based food products to obtain a database of 317 papers. Thirty four publications met the criteria for review.
Findings
Jamun fruit (Syzygium cumini L.) is known for its attractive colour, astringent taste, enormous nutrients and nutraceutical properties; nevertheless, this fruit is seasonal, perishable and underutilised. Furthermore, the fruit is used for the treatment of diabetes and also possess anti-cancer, anti-inflammatory, anti-obesity and cardio-protection properties. Investigations were done on the production of value-added food products such as read-to-serve beverages, jam, cookies and cake from jamun due to their several health benefits. The present review was an attempt to provide spotlights on the health benefits and food product applications of jamun fruit and its by-products.
Originality/value
This review systematically collates evidence from various published sources regarding the nutritional profile, development of food products from jamun and their health benefits. The compiled information will help researchers and professional become aware of the significance of jamun fruit and thereby enhances its processing and applications in food systems.