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The purpose of this study is to introduce a new type of sensor which uses microwave metamaterials and direct-coupled split-ring resonators (DC-SRRs) to measure the dielectric properties of solid materials in real time. The sensor uses a transmission line with a bridge-type structure to measure the differential frequency, which can be used to calculate the dielectric constant of the material being tested. The study aims to establish an empirical relationship between the dielectric properties of the material and the frequency measurements obtained from the sensor.

In the proposed design, the opposite arm of the bridge transmission line is loaded by DC-SRRs, and the distance between DC-SRRs is optimized to minimize the mutual coupling between them. The DC-SRRs are loaded with the material under test (MUT) to perform differential permittivity sensing. When identical MUT is placed on both resonators, a single transmission zero (notch) is obtained, but non-identical MUTs exhibit two split notches. For the design of differential sensors and comparators based on symmetry disruption, frequency splitting is highly useful.

The proposed structure is demonstrated using electromagnetic simulation, and a prototype of the proposed sensor is fabricated and experimentally validated to prove the differential sensing principle. Here, the sensor is analyzed for sensitivity by using different MUTs with relative permittivity ranges from 1.006 to 10 and with a fixed dimension of 9 mm × 10 mm ×1.2 mm. It shows a very good average frequency deviation per unit change in permittivity of the MUTs, which is around 743 MHz, and it also exhibits a very high average relative sensitivity and quality factor of around 11.5% and 323, respectively.

The proposed sensor can be used for differential characterization of permittivity and also as a comparator to test the purity of solid dielectric samples. This sensor most importantly strengthens robustness to environmental conditions that cause cross-sensitivity or miscalibration. The accuracy of the measurement is enhanced as compared to conventional single- and double-notch metamaterial-based sensors.

This paper aims to concentrate on research that has been conducted in the previous decade on metamaterial (MTM)-based sensors for material characterization, which includes solid dielectrics, micro fluids and biomolecules.

There has been a vast advancement in sensors based on MTM since the past few decades. MTM elements provide a sensitive response to materials while having a tiny footprint, making them an appealing alternative for realizing diverse sensing devices.

Related research papers on MTM sensors published in reputable journals were reviewed in this report, with a specific emphasis on the structure, size and nature of the materials characterized. Because electromagnetic wave interaction excites MTM structures, sensing applications around the electromagnetic spectrum are possible.

The paper contains valuable information on MTM sensor technology for material characterization, and this study also highlights the challenges and approaches that will guide future development.

The purpose of this paper is to retrieve the dielectric constant of the material under test (MUT) by using an empirical relationship, which relates the dielectric properties with all three resonant frequencies of the proposed sensor. Each notch of the sensor is analyzed for sensitivity by using 15 different MUTs with relative permittivity ranging from 1.006 to 16.5 with a fixed dimension of 12 mm × 12 mm × 1.2 mm.

In this paper, we present a triple-notch metamaterial-based sensor for the solid dielectric characterization based on a microstrip transmission line and a direct coupled-double split ring resonator (DC-DSRR). The proposed sensor is designed, and its response is measured using a vector network analyzer to verify the concept. The shift in the resonant frequencies of the proposed sensor owing to contact with MUT is depicted as a function of permittivity using the curve fitting tool.

The proposed sensors have three notches, with the third notch being more sensitive than the first and second notch because of the high resonance frequency. For the first, second and third resonances, the proposed sensor has sensitivity ranges from 4.9% to 14.68%, 8.97% to 23.95% and 15.48% to 29.36%, respectively. The findings of the simulations, measurements and formulations are all in good accord.

In comparison to previous solid dielectric metamaterial sensors, the proposed triple-notch sensor based on a microstrip transmission line and DC-DSRR has the following advantages: it has a simple unit-cell structure and meets the needs of miniaturization, compact size, low cost and improved sensitivity. It determines the relative permittivity using all three notches so that the accuracy of the measurement is enhanced as compared with single- and double-notch sensors.

The purpose of this paper is to model and investigate collaborative culture and relationship strength roles in supply chain collaboration. This research highlights critical role played by culture and relationship strength in collaboration.

Drawing from relational view, a conceptual model is developed with the help of literature, and the model is validated with data collected in India using partial least squares method.

Results and analyses revealed that culture and relationship strength significantly and strongly influence each collaborative activity. The relationship strength fully mediates between collaborative culture and supply chain performance. The research also finds that the relationship strength partially mediates between collaborative culture and market-based information sharing, operational resource planning and sharing. In the long-term, collaborative culture drives relationship strength and the element enhances collaborative activities.

This research attempted to explore collaborative culture and relationship strength which are crucial for collaborative relationship. Many mediation effects are studied which increase the understanding and give insights for its implementation. Its theoretical and practical implications are highlighted. This knowledge has enough potential to lead collaborative relationships towards success.

The “war for talent” is not limited to developed economies but has become a common feature in emerging economies such as India. From the sociocultural perspective, India represents one of the oldest cultural heritages with distinct cultural values. The cultural difference may contribute to explain organizational practices toward talent retention. In the present chapter, the authors focus on the institutional, legal, and cultural context and highlight their uniqueness with respect to the Indian context. Within the institutional context, the authors found that prior to liberalization (which happened in 1990s), the Indian business scene was dominated by public firms or a small enclave of private firms. For both types of organization, turnover hardly mattered, and turnover was indeed negligible. Employees saw firms as “employers for life”: in such a context, voluntary turnover was extremely rare. Further, in the early legal context, it was hard for any private firm to “fire” an employee. Therefore, involuntary turnover was close to nil as well. Things began to change post-liberalization when the Indian scene was dominated by an influx of private players. The Indian mind too accepted turnover to be a part of the corporate life. In the present chapter, the authors provide a snapshot of what, why, and how of employee turnover in the Indian context. The authors specifically focus on what motivates employees to remain with the organization or why do they leave the organization. The authors close the chapter with insights relevant to both academicians and practitioners.

No fault found (NFF) in maintenance has been a frequently observed problem in industrial sectors, but very few academic contributions are devoted to reviewing and summarizing the related research. Considering the growing interest of academicians in NFF during the last decade, there is a critical need to examine theme evolution in this field, most influential authors, contemporary practices, research gaps and proposed solutions.

A portfolio of 169 articles published between 1982 and 2020 was collected from the Scopus database and was systematically analyzed using a two-tier method. First, the evolution, current state of literature and research clusters are identified using bibliometric techniques. Finally, the research clusters are studied to understand the literature's main themes and develop the future research agenda using content analysis.

The results indicate that publications on NFF are rising quickly in the last decade, especially after 2010. The previous NFF research primarily focuses on system design, fault diagnostics, reliability engineering, data management and human factors, but the criticality of economic and risk analysis has not been significantly represented.

The study resulted in developing an inclusive framework and identifying six research clusters that will help in granular understanding, benefit the researchers, practitioners and policy formulators in NFF.

This study examines the NFF's current research direction and calls for further research in integrating NFF economics on its stakeholders like manufacturers, supply chain, customers and risk analysis during the product life cycle.

The paper aims to fabricate shape memory composites using polylactic acid (PLA) matrix and graphite. Shape memory polymers are a promising family of materials for biomedical applications because of their favourable mechanical properties, fast reactions and good biocompatibility. For most SMPs, however, achieving controllable sequential shape change is challenging.

In the present work, 4D printing technology is used to fabricate shape memory composites using polylactic acid (PLA) matrix and graphite. A comparative study of pure PLA and graphite’s different weight % composition has been done.

By carefully managing the deformation state, PLA with graphite shape memory composites produced controllable sequential deformation with an amazing shape memory effect. Surface morphology, thermal properties, melt flow index and shape recovery tests have all been carried out to assess the qualities of manufactured samples.

This is a one-of-a-kind to fabricate shape memory composites using graphite and a PLA matrix. Thus, this research attempts to deliver the possible use of PLA/graphite composites fabricated using 4D printing in robotics and biomedical devices.

The present investigation aims to examine the reflection of plane waves from a free surface of a thermodiffusive elastic half space with void.

Generalized theory of thermoelasticity developed by Lord‐Shulma was used to investigate the problem. The amplitude ratios of various reflected waves are obtained in a closed form. The dependence of these amplitude ratios with an angle of propagation as well as other material parameter are shown graphically.

Effects of void and diffusion are observed on these amplitude ratios and have been found to be significant.

It is found that there exist four longitudinal waves (namely P‐wave, thermal wave (T‐wave), mass diffusion wave (MD‐wave), volume fraction wave (VF‐wave, carrying a change in void volume fraction) and a transverse SV wave). Some special cases of interest are also deduced from the present investigation.

The purpose of this paper is to understand disparities in child immunization and nutritional status among children by migration status in urban India.

The study utilized third round of National Family Health Survey (NFHS, 2005-2006) data, which is the Indian version of Demographic and Health Survey. Descriptive statistics and binary logistic regression models were used to study the levels and factors associated with child nutrition and immunization by migration status.

Results suggest that malnutrition and no immunization are very high among children of rural-urban migrants and full immunization is lower than urban non-migrants and urban-urban migrants. More than half of the children from marginalized households suffer from the problem of undernutrition among rural-urban migrants. Multivariate results show economic status, age of the mother, education, caste and media exposure are negatively associated with malnutrition and positively associated with immunization. Children from south, north-east and east are found to have lesser chance of being malnourished than north region of India.

The challenges experienced by rural-urban migrants are reflected over their children and needs a greater attention among policy makers in India.

The finding of this study that children of the rural-urban migrants are in a disadvantageous position in terms of nutrition and immunization. This reflects the precarious condition of rural-urban migrants who initially settles in poor neighbourhoods, which are characterized by lack of adequate sanitation and clean water, poor housing and overcrowding, and difficulty in access to modern health services brought out by many researchers.

This research aims to develop a new generic framework for estimating different maintenance costs (preventive, corrective and conditional based) and its distribution to original equipment manufacturer (OEM), customer and supply chain due to no fault found (NFF) events. The study extend the domain of NFF to military aircraft maintenance, repair and overhaul (MRO) by including broader range of cost drivers than are normally found in maintenance NFF literature.

The research applies the soft system methodology involving 80 field surveys and five in depth semi-structured interviews with practicing experts having background in military aircraft NFF MRO. For impact analysis, authors have used an agent-based model to represent and prioritize the critical NFF cost drivers during aircraft MRO based on the cost inputs of 21 technology transfer cases.

The paper provides imperial insights about how NFF cost drivers affect the OEM, customer and supply chain. It suggests that NFF cost need to be part of the commercial MRO contract, depending on its frequency pattern in different types of maintenances.

The context of the current research is military aircrafts industry and may lack generalizability to commercial aircrafts. Therefore, researchers are encouraged to test the proposed propositions further.

The developed framework will provide invaluable help in key financial decision-making during signing of MRO contract in technology transfer cases.

This paper proposed a new prediction model for NFF cost estimation across its shareholders and current status of NFF in military aircraft NFF MRO in India.