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This review article explores the advancement of metasurfaces in wearable antenna design for off-body communications. The wearable antenna needs to be compact, flexible, and, most importantly, should have less back radiation. In this context, wearable antennas that are inspired by metasurfaces are a good choice. Metasurface can make the antenna compact and reduce the back-radiated waves, which lowers the specific absorption rate (SAR) and improves the antenna's performance. In addition, the metasurface can also generate circular polarization (CP) by carefully rotating the electromagnetic (EM) waves incident on it and multi-band by simultaneously exciting its multiple modes. Using the aforementioned features provided by the metasurface, the surveys are segregated as single-band with linear polarizations (LP), single-band with CP, dual-band with LP, dual-band with dual polarization, and dual-band with dual CP. Prior to the survey, the challenges and considerations for wearable antenna design as well as the theoretical perspective behind performance improvements are discussed. Also, a conventional unit-cell of the metasurface is theoretically designed using the discussed theories and validated using CST Microwave Studio, which shows good agreement with each other. [ABSTRACT FROM AUTHOR]

Purpose: Scarcity of resources and ever-changing demand have attracted the government and manufacturers for an integrated sustainable-green-lean-six sigma-agile manufacturing system (ISGLSAMS). Many organizations failed to adopt ISGLSAMS due to various barriers. The purpose of this paper is to identify and rank the various barriers to ISGLSAMS and to analyze the correlations among the various barriers to ISGLSAMS so that the adoption of ISGLSAMS can be implemented in manufacturing organizations for more sustainable development of the industries, and industrial ecology. Design/methodology/approach: A three tiers methodology is used to analyze the barriers to the adoption of ISGLSAMS. First, a total of 24 ISGLSAMS barriers are identified through a comprehensive literature review. Then data are collected with a structured questionnaire from 108 Indian manufacturing industries. Then, the sign test is used to check the relevance and significance of barriers. Then ISGLSAMS barriers are ranked based on the median and standard deviation. Spearman's correlations between the ISGLSAMS barriers are identified and studied to strengthen the in-depth understanding of correlations among the barriers. Findings: The result shows that most of the Indian manufacturing industries agreed with the selected barriers to the adoption of ISGLSAMS. Low supplier commitment, uncertain financial benefits, the misconception of high cost, difficulty in evaluation of system performance throughout the life cycle, complexity in ISGLSA process design, the complexity of management of ISGLSAMS, complexity in ISGLSA system design, lack of updated information, complexity in ISGLSA product design and uncertain future legislation are found the major barriers for the ISGLSAMS in Indian manufacturing industries. While lack of leadership, low top management commitment, lack of government support, organizational structure, low employees' commitment, technological risk and low public pressure are considered minor barriers for the ISGLSAMS. Inter-relationships study of the barriers further contributes to the methodology to overcome the barriers. Practical implications: The study contributes to a better understanding of ISGLSAMS barriers. Through this study, government, stakeholders and policymakers may plan the policy, roadmap and strategies to overcome the barriers to the ISGLSAMS. This will lead to the successful adoption of ISGLSAMS for more sustainable development of manufacturing industries in India. Originality/value: This work contributes to identifying the barriers to a more sustainable manufacturing system, i.e. ISGLSAMS (7Rs based), and prioritizing them in Indian manufacturing industries. The research also contributes to the (1) study of inter-relationships among the ISGLSAMS barriers for analyzing the effect of one barrier over another barrier, and (2) ISGLSAMS literature because the sustainable manufacturing literature still lags the achievement of sustainability goals due to 6Rs focus. [ABSTRACT FROM AUTHOR]