Purpose – In present context of globalization, maintenance of production systems is very important. Many of the organizations are facing a lot of problems in maintenance management. Therefore the purpose of this paper is to identify the main barriers in maintenance management and to rank them for effective maintenance strategies. Design/methodology/approach – To rank the main barriers in maintenance management, technique for order preference by similarity to ideal solution is used. For giving score to different factors a team of three experts was made. All experts were having more than ten years of experience in area of maintenance management. Findings – Lack of top management support, lack of measurement of overall equipment effectiveness (OEE) and lack of strategic planning and implementation have emerged as top three barriers in implementation of maintenance systems in industries. Research limitations/implications – Findings imply that for successful maintenance, top management should be very supportive for taking different initiatives, training programmes, etc. Organizations should try to improve overall performance of machines known as OEE rather than only machines productivity. Originality/value – These findings will be highly useful for professionals from manufacturing sector in implementing effective maintenance management system.

In the present article, a compact triple‐band multistubs loaded resonator printed monopole antenna is proposed. The antenna consists of a quarter wavelength two asymmetrical inverted L‐shaped stubs to excite two resonant modes for 3.5/5.5 GHz bands and one integrated horizontally T‐shaped stub with inverted long L‐shaped stub to excite resonant mode for 2.5 GHz band. By loading these stub resonators along y‐axis with distinct gaps, the antenna resonates at three frequencies 2.57/3.52/5.51 GHz covering the desired bands while keeping compact size of 24 × 30 mm2 (0.2  λ0 × 0.25 λ0). The proposed antenna is fabricated on Rogers RT/duroid 5880 substrate with thickness 0.79 mm and its performance experimentally verified. The measured results reveal that the antenna has the impedance bandwidths of about 210 MHz (2.50‐2.71 GHz), 260 MHz (3.37‐3.63 GHz), and 650 MHz (5.20‐5.85 GHz), for 2.5/3.5/5.5 GHz WiMAX and 5.2/5.8 GHz WLAN band systems. The antenna provides omnidirectional radiation patterns and flat antenna gains over the three operating bands. In addition, the design approach and effects of multistubs resonator lengths on the operating bands are also examined and discussed in detail.

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This article describe the design and measurement of a broadband circularly polarized (CP) monopole antenna for millimeter wave short range 5G Wireless communication applications. This antenna is comprised of a T-shaped monopole antenna with an inverted-L grounded stub and an asymmetric coplanar wave guide feed. To attain the broadband CP, an inverted-L grounded stub is embedded in the coplanar ground and introducing asymmetry in the horizontal T-shaped patch connected feed line monopole antenna. A compact size of 1.877λ L × 1.706λ L × 0.130λ L is accomplished when measured at lower edge frequency (f L,|S11|). For the proposed antenna structure conforming to f L,|S11| , a measured 3-dB axial ratio bandwidth of 13.67% (4 GHz, 27.26-31.26 GHz), impedance bandwidth of 27.9% (8.3 GHz, 25.6-33.9 GHz), peak gain of 7.15dBi, and a bidirectional patterns with a dual sense polarization are attained.