• Journal of electromagnetic engineering and science
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• v.7 no.2
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• pp.96-101
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• 2007

A design of circular polarized(CP) microstrip antenna with a fenced ground is proposed and the equivalent circuit is derived. The antenna consists of a square radiating patch with a pair of truncated comers, a bottom ground and a fenced ground. From conducted experiments, a patch size reduction using the metal fence as large as 25% from the conventional patch structure, has been obtained. The input admittance of the extracted equivalent circuit is shown to agree with that of the measurement. And the design parameters and performance of the proposed antenna are examined by analyzing the fields and circuit behaviors.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.128-132
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• 2022

Wild boars (Sus scrofa) not only cause crop damage and human casualties, but also facilitate the spread of many infectious diseases in domestic animals and humans. To determine the efficiency of a fencing system in blocking the movement of wild boars, long-term monitoring was performed in a fenced area in Bukhansan National Park using camera traps. Upon monitoring for a period of 46 months, there was a 72.6% reduction in the number of wild boar appearances in the fence-enclosed area, compared to that in the unenclosed area. For 20 months after the fence installation, the blocking effect of the fence was effective enough to reduce the appearance of wild boars by 92.6% in the fence-enclosed area, compared to that in the unenclosed area. The blocking effect of the fence remained effective for 20 months after its installation, after which its effectiveness decreased. Maintaining a fence for a long time is likely to lead to habitat fragmentation. It can also block the movement of other wild animals, including the endangered species - the long-tailed goral. This study suggests a 20-month retention period for the fences installed to inhibit the movement of wild boars in wide forests such as Gangwon-do in South Korea. To identify how long the blocking effect of the fences lasts, further studies are needed focusing on the length and height of the fence, and the conditions of the ground surface.