PURPOSES: The objective of this study is to investigate the properties of recycled asphalt binders with five different rejuvenators, in order to evaluate the applicability of the recycled asphalt binders compared with the original asphalt binder. METHODS: In order to simulate recycled asphalt binders, fresh asphalt binders are aged by various Superpave aging procedures, such as the rolling thin-film oven (RTFO) and the pressure aging vessel (PAV). Then, selected rejuvenators are added to the aged asphalt binders in the amount of 5%, 10%, and 15%. The asphalt binder properties are evaluated by the dynamic shear rheometer (DSR), the rotational viscometer (RV), and the bending beam rheometer (BBR). In this study, AP-5 (penetration grade 60-80, PG 64-16) asphalt binder is used. A total of five types of rejuvenators are employed. RESULTS AND CONCLUSIONS : When considering aged asphalt without a new asphalt binder, it seems that the percentage of rejuvenator used in Korea is a bit too low, and that it fails to possess the characteristics of the original binder. From the current practice of evaluating the properties of recycled binder based on penetration ratio only, the amount of rejuvenator required is similar for the long-term-aged binder, but is excessive for the longest-term aged binder, causing deterioration of workability and stiffness of the recycled binder.

Sweet potato whitefly (SPW), Bemisia tabaci, is the most serious pest of greenhouse tomato as a vector of tomato yellow leaf curl virus since 2008 in Jeju. This study was conducted for within-plant distribution of SPW nymphs on leaves and the characteristic of spatial distribution of SPW adults using by yellow-color sticky trap in greenhouse-grown tomato plants. The nymphs of SPW were mainly distributed on leaves of mid-lower stratum in three stratum of tomato plant. They were also more distributed on three to four leaflets from basal part in a leaf. Ten plots and three plants per plot were appropriated to estimate of mean density of SPW nymph using by visual inspection in a tomato greenhouse. The more SPW adults were caught on horizontally placed sticky trap above 50～80 cm than vertically placed sticky trap above tomato canopy. The horizontal direction trap should be placed in opened site. SPW adults were shown the aggregated distribution pattern using by Taylor’s power law (TPL) and Iwao’s patchiness regression (IPR) model which are commonly used for spatial distribution pattern analysis. TPL was showed better description than IPR for spatial distribution pattern of SPW adults. The required number of trap tended to decrease according to increase the mean density of SPW adult

Beet armyworm (BAW), Spodoptera exigua (Hübner), is a polyphagous lepidopteran pest mainly distributed in tropical and subtropical regions. BAW are known to migrate long distances to find suitable host plants and environmental condition. The possibility of its overwintering in temperate regions has been suspected. This study was conducted for investigating overwintering and phenology of BAW using by sex pheromone trap in Jeju during 2007 to 2011. BAW was able to overwinter at pupae stage regardless of temperature of winter season in Jeju. The times of BAW caught first on traps were different by surveyed years - early March in 2007, middle March in 2008 and 2011 and early April in 2009 and 2010. The times of BAW caught on trap tended to be more dependent on temperature variation during on November and December than on mean temperature of winter season. The peak season of adults of the overwintering generation was early to middle of May. The results of seasonal periodicity of BAW monitored by sex pheromone trap during 2009 and 2010 indicated that five generations were passed in Jeju. The peak season of 1st generation was on middle of April, 2nd generation on middle of July, 3rd generation on early of August, 4th generation on late of August and 5th generation on middle of September. There were similar patterns by different above sea levels except the season of overwintering generation adults occurrence (March to May).

Arrowhead scale, Unaspis yanonensis, is a serious scale insect pest of citrus in Jeju. The sticky taping of 1.0 cm diameter twig was a good survey method for arrowhead scale crawler. There are three times crawler occurrence season - late May to early July, late July to middle September and late September to late October. But the third occurred crawlers are all died during overwintering in open-field groves. This study was conducted to provide information on efficient sampling plan for arrowhead scale within the tree. Twig and fruit was fit for secondary sample unit by two-stage variance analysis. Both sample number per tree (primary sample unit) was eight twigs or fruits. Taylor’s power law was better described the distribution characteristic of arrowhead scale than Iwao’s patchiness regression. The slope of both linear regressions was greater than “1” which means aggregative distribution pattern. Minimum sample size to estimate the density was calculated using by two parameters of Taylor’s power law. To estimate the mean density on twig and fruit by binomial sampling plan, the optimum tally threshold was 5 and 7, respectively.