Mating disruption (MD) using synthetic sex pheromone lures has been used to control the Oriental fruit moth, Grapholita molesta (Busck), in apple orchards. In Korea, where several small apple orchards are clustered but independently managed, its efficacy has been suspected mainly due to immigration of any mated females from nearby untreated cultivating areas. This study developed an edge treatment technique to decrease any local MD-free zones in a specific MD-treated farm and to trap any immigrating mated females by installing MD lures and food traps around the apple farm with 10 meter intervals. The addition of the edge treatment to the MD significantly prevented leaf and fruit damages induced by G. molesta compared to MD only. Moreover, this study tried to optimize the MD control technique by determining frequency of MD application. It suggests two MD applications with the edge treatment at the end of March and at the early of July to be effective throughout the entire apple growing seasons.
Recently, metal molding has become essential not only for automobile parts, but also mass production, and has greatly influenced production costs as well as the quality of products. Its surface has been treated by carburizing, nitriding and induction hardening, but these existing treatments cause considerable deformation and increase the expense of postprocessing after treatment; furthermore, these treatments cannot be easily applied to parts that requiring the hardening of only a certain section. This is because the treatment cannot heat the material homogeneously, nor can it heat all of it. Laser surface treatment was developed to overcome these disadvantages, and, when the laser beam is irradiated on the surface and laser speed is appropriate, the laser focal position is rapidly heated and the thermal energy of surface penetrates the material after irradiation, finally imbuing it with a new mechanical characteristic by the process of self-quenching. This research estimates the material characteristic after efficient and functional surface treatment using HPDL, which is more efficient than the existing CW Nd:YAG laser heat source. To estimate this, microstructural changes and hardness characteristics of three parts (the surface treatment part, heat affect zone, and parental material) are observed with the change of laser beam speed and surface temperature. Moreover, the depth of the hardened area is observed with the change of the laser beam speed and temperature.