No abstract

This paper proposes the switched beam antenna array at the center frequency of 2.45GHz with a bandwidth of 187 MHz, from 2.32 GHz to 2.51 GHz. The phase shifter of antenna utilizes a 4×4 planar Butler matrix with phase differences between its outputs of  ±135° and ±45° to obtain four the different main beam directions. The proposed design is fully described including the patch antenna element, the antenna array, the phase shifter that forms the completed antenna array. The antenna array achieves a gain max up to 7 dBi, and the angles of the main beam directions of -41°, -12°, +15°, +48° in a horizontal plane. The beamwidth of the four main beams is from 26°  to 31.8° in E-plane and from 38.5° to 55.4° in H-plane. The advantage of the antenna is the planar structure and compact dimension of 200×230mm2. The proposed antenna is suitable for ISM band.

No abstract

The aim of the study conducted from April to December 2022 was to assess theeffectiveness of Pesguard FG161, a commercial insecticide formulation from SumitomoChemical Co., Ltd, against field bed bugs. This emulsifiable concentrate (EC) formulationcombines two active ingredients, D-Tetramethrin and Cyphenothrin, and is recommendedfor indoor residual spraying. Populations of the bed bug Cimex lectularius collected inTrung Van commune, Nam Tu Liem district (Trung Van strain), Ha Noi, and in ThinhLang commune, Hoa Binh district, Hoa Binh province (Thinh Lang strain) were evaluatedusing the surface contact method. Exposure time was 4 hours, and the mortality of bedbugs in contact with the treated panel was recorded on a daily basis for up to 4 days, andthe residual bioefficacy of the product was evaluated after one day, seven days, and thirtydays of spraying. According to the study, Pesguard FG161 can effectively control fieldbed bugs, as evidenced by its high success rate in killing them (mortality were 100%)