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The purpose of this paper is to predict permittivity of leafy vegetation using overlay technique.

The paper studies X band moisture dependent microwave permittivity of the stem and leaf of Ficus Bengalensis using overlay on Ag thick film microstripline. The perturbation obtained in the transmission and reflectance of the thick film microstripline due to the leafy vegetation overlay has been used to obtain the permittivity.

The paper finds that the permittivities obtained are in the range expected of leafy vegetation with moisture. Only the amplitude data have been used here. As the moisture content decreases, the dielectric constant and dielectric loss decrease. The return loss characteristics show interesting frequency dependent behaviour due to both stem and leaf overlay.

The paper is original in that a non‐resonant microstrip component has been used for the first time for such studies. The thick film component along with overlay can be a cost‐effective dielectric sensor especially for biomaterials, since any size and shape of the overlay can be used.

Although social distancing measures enacted during COVID-19 prevented the spread of the virus and acted as important coping mechanisms during this stressful time, they also contributed to loneliness and anxiety. The pros and cons of social distancing measures were especially relevant among people with disabilities and chronic health conditions – a high-risk group concerned about infection through contact with non-household members and visiting public places like school, healthcare providers, and work.

Drawing on data from a national online survey (N = 1,027) and in-depth virtual interviews (N = 50) with Canadians with disabilities and chronic health conditions, we examine the positive and negative effects of three types of social distancing measures – avoiding public places, transitioning to remote work or school, and avoiding contact with non-household members – on perceptions of increases in anxiety and loneliness during the pandemic.

We find that the relationships between engaging with social distancing measures and anxiety and loneliness could be positive or negative, with measures acting as both adaptive and maladaptive coping mechanisms. Although avoiding public places or non-household members and transitioning to remote work or school often resulted in increased anxiety and loneliness, respondents also described situations where these measures helped them cope with concerns about catching COVID-19.

Our findings highlight potential implications for public health policy in allocating different coping resources among marginalized groups during times of crisis and demonstrate the importance of using a social model of stress, coping mechanisms, and mental health.

The purpose of this paper is to describe the use of copper‐substituted nickel manganite thick film and bulk ceramic superstrate on Ag thick film microstrip straight resonator (MSR), to modify its response and measure complex permittivity as a function of copper.

The glass frit free (fritless) copper‐substituted nickel manganite thick films were formulated on alumina substrate by screen printing technique from the powder synthesized by oxalic precursor method. A comparison has been made between the X band response of Ag thick film MSR due to perturbation of bulk and thick film Ni_(1−x)Cu_xMn₂O₄ (0≤x≤1) ceramic. The shift has been used to measure the permittivity of the ceramic. The dielectric constants obtained by superstrate technique on Ag thick film microstrip component are comparable to those obtained from theoretical calculations.

The resonance frequency of MSR shifts towards lower frequency due to the presence of Ni_(1−x)Cu_xMn₂O₄ (0≤x≤1) ceramic as superstrate. The dielectric constant of bulk and thick film match well with the theoretical values. The dielectric constant increases with copper concentration and shows reduction of power gain of MSR. The peak output (power gain) of MSR due to thick film NiMn₂O₄ increases by 10.19 per cent with decrease in bandwidth and increase in the quality factor with copper concentration.

The superstrate on Ag thick film straight resonator is an efficient tool capable of detecting the composition‐dependent changes in microwave properties of ceramic thick films. These Ni_(1−x)Cu_xMn₂O₄ ceramic being thermistor materials apart from modifying the response can also be used as power sensors providing cost‐effective miniaturization.

The purpose of this paper is to report on the Ku band microwave characteristics of moisture laden soya seeds using overlay technique.

Ku band (13‐18 GHz) moisture dependent microwave permittivity, conductivity, penetration depth of moisture laden soybean (Glycine Max) using overlay on Ag thick film equilateral triangular patch antenna are studied. The change in the frequency response of the patch antenna due to change in moisture content of the soybean overlay has been used to obtain the various microwave properties.

The permittivities obtained are in the range expected of moisture laden soybean. As moisture content increases microwave dielectric constant, dielectric loss, and conductivity of soybean increases. Only the amplitude data have been used here.

Ku band characterization of soybean has been done using overlay technique. The thick film patch antenna is sensitive even to ∼4 percent moisture content in the overlay material. This can be used for even moisture sensing at low moisture levels. This paper is believed to be an original research report.

This study aimed to understand the extent to which cannabis-related risk perception and COVID-19-related health worries were associated with the reported reduction in sharing cannabis smoking products to mitigate the risk of the coronavirus transmission or infection. This association was tested in two different periods in terms of toughness of national lockdown policy imposed in the first months of the pandemic in Israel.

The study population included adult recreational cannabis users who completed one of the two online cross-sectional surveys dedicated to COVID-19 and the cannabis use situation in Israel in the first half of the 2020. The two surveys were conducted six weeks apart. One survey was conducted in the period when strict lockdown measures were in place (N₁ = 376). The other survey was conducted in the period when many lockdown measures were lifted (N₂ = 284). Differences between the samples regarding risk perception, health stressors and reduction in sharing cannabis products were assessed using t-test. Regression analysis was used to test the independent correlates of reported reduction in sharing cannabis products.

Means of risk perception, health stressors and reported reduction in sharing cannabis products were higher in the sample surveyed in the period of the strict lockdown measures than in the sample surveyed in the period of eased lockdown measures. Risk perception was associated with reported reduction in sharing cannabis products only in the sample surveyed in the period of strict lockdown measures. In contrast, health stressors were related to reported reduction in sharing cannabis products in both samples.

Health stressors may represent a more stable mechanism by which cannabis users engage in protective behavior during the pandemic than risk perceptions.

To the best of the authors’ knowledge, the current research is one of the first studies that examine the associations among risk perception, primary stressors and protective behavior in recreational cannabis users while referring to cannabis-related behavior other than use.

Multi-jet deposition of the materials is a matured technology used for graphic printing and 3 D printing for a wide range of materials. The multi-jet technology is fine-tuned for liquids with a specific range of viscosity and surface tension. However, the use of multi-jet for low viscosity fluids like water is not very popular. This paper aims to demonstrate the technique, particularly for the water-ice 3 D printing. 3 D printed ice parts can be used as patterns for investment casting, templates for microfluidic channel fabrication, support material for polymer 3 D printing, etc.

Multi-jet ice 3 D printing is a novel technique for producing ice parts by selective deposition and freezing water layers. The paper confers the design, embodiment and integration of various subsystems of multi-jet ice 3 D printer. The outcomes of the machine trials are reported as case studies with elaborate details.

The prismatic geometries are realized by ice 3 D printing. The accuracy of 0.1 mm is found in the build direction. The part height tends to increase due to volumetric expansion during the phase change.

The present paper gives a novel architecture of the ice 3 D printer that produces the ice parts with good accuracy. The potential applications of the process are deliberated in this paper.

The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome these barriers for improved operational efficiency in the Indian context.

The methodology used interpretive structural modelling (ISM), cross-impact matrix multiplication applied to classification (MICMAC) analysis and decision-making trial and evaluation laboratory (DEMATEL) to understand the hierarchical and contextual relations among the barriers of the post-processing.

A total of 11 post-processing barriers were identified in this study using ISM, literature review and experts’ input. The MICMAC analysis identified support material removal, surface finishing, cleaning, inspection and issues with quality consistency as significant driving barriers for post-processing. MICMAC also identified linkage barriers as well as dependent barriers. The ISM digraph model was developed using a final reachability matrix, which would help practitioners specifically tackle post-processing barriers. Further, the DEMATEL method allows practitioners to emphasize the causal effects of post-processing barriers and guides them in overcoming these barriers.

There may have been a few post-processing barriers that were overlooked by the Indian experts, which might have been important for other country’s perspective.

The presented ISM model and DEMATEL provide directions for operation managers in planning operational strategies for overcoming post-processing issues in the medical 3D-printing industry. Also, managers may formulate operational strategies based on the driving and dependence power of post-processing barriers as well as the causal effects relationships of the barriers.

This study contributes to identifying, analyzing and modelling the post-processing barriers of 3DPMM through a combined ISM and DEMATEL methodology, which has not yet been reviewed. This study also contributes to decision makers developing suitable strategies to overcome the post-processing barriers for improved operational efficiency.

Good management strives to align and corporate processes for more attention being paid to supply chain management. Firms realize that greater co-operation and improved coordination can help to manage the entire supply chain more efficiently. The imperfect quality item is one of the most important issues that affect the expected profit of green supply chain. The imprecise cost with screening process of poor quality items posed in supply chain is the subject of this study.

The present study explores production model for imperfect items having uncertain cost parameters with three-layer supply chain encompassing supplier, manufacturer and retailer. The model is considering the impact of business tactics such as order size, production rate, production cost and appropriate times in various sectors on collaborative marketing systems. Due to imprecise cost parameters, the pentagonal fuzzy numbers are set to fuzzify the total cost and defuzzifition by using graded mean integration.

This study offers an explicit condition in uncertain environment to manage the imperfect quality item to increase the potential profit of the supply chain. The influence of changes in parameter values on the optimal inventory policy under fuzziness is provided managerial insights.

This model makes a significant contribution to fuzzy inference. The results of the study provide a trading strategy for the industry to avoid losses. The prescribed study can be suitable for the industries like sculpture, jewelry, pottery, etc.

The digital warehouse management system is an emergence that forms a critical part of the transformation of economic structure in Industry 4.0. In the present business scenario, the warehouse management system encounters a messy layout, poor damage control, unsatisfactory order management, lack of visibility and lack of technological interventions. Digital twin (DT) based warehouse system shows the ontology and knowledge graphs for competitive advantage by consolidating and transferring goods directly from an inbound supplier to an outbound customer on short notice and with no or limited storage. There remains a lack of clarity on how the DT can be implemented successfully in warehouse management.

The current literature remains largely unstructured and scattered due to a lack of a systematic approach to integrating the research implications and analysis. This paper probes the conceptualization of the DT with the help of theoretical analysis using the systematic literature analysis method.

The study explores essential concepts such as interoperability and integrability in implementing DT. Further, it analyzes the role of a supply chain control tower (SCCT) in modern supply chain management. A research framework is proposed for practitioners and academicians by incorporating the opportunities and challenges associated with DT implementation. The research findings are mainly threefold: Conceptualization of DT, Featuring SCCT and Exploration of cross-computer platform interfaces, scalability and maintenance strategies.

This study is among the first to analyze and review DT applications in warehouse management. Moreover, the study proposes a theoretical toolbox for the practitioners to successfully implement the DT in warehouse DT-based warehouse management system: A theoretical toolbox for future research and applications.

The purpose of the article is to report a study on evaluation of smart manufacturing (SM) performance using a grey theory-based approach.

In total, 30 criteria and 79 attributes for SM performance have been developed. A grey theory-based approach has been used for SM performance evaluation. The grey index has been calculated, and weaker areas have been derived. Performance level of SM has been evaluated using the Euclidean distance approach.

The SM performance index is found to be (3.036, 12.296). The ideal grey performance importance index (GPII) is obtained as (3.025, 4.875). The level of visibility and traceability, vertical integration, lead time and configuration data espionage and control ability are strong performing attributes. Integration abilities of services and manufacturing systems, ability of self-control, worker and raw material productivity, collaboration among buyers and suppliers and dynamic scheduling are identified as weaker areas, and suggestions for improvement have been derived. SM performance level has been identified as “Good.”

Additional performance measures could be included as a part of evaluation. Practitioners can overcome weaker areas in the early phase. Management achieves confidence and practitioners attain success in implementation of SM in industry through the developed SM performance indexing system.

Identification of SM performance measures and analysis of SM performance is the original contribution of the authors. The developed approach assists practitioners and managers to focus more on specific areas for performance improvement.