• 대한지리학회지
• /
• 제16권
• /
• pp.35-53
• /
• 1977

• 한국환경과학회지
• /
• 제23권8호
• /
• pp.1385-1394
• /
• 2014

Metcalfa pruinosa was considered to be a very harmful invasive species, due to its high species density in nature and wide range of its host plants. M. pruinosa was distributed in 28 sites among 143 sites. M. pruinosa has wide range and diverse host plants of 52 families 110 species including crop, fruits and forest trees. At present, the identified host plant of M. pruinosa are composed of 62 families and 145 species in total since their first appearance was reported. M. pruinosa was found in roadside 46.7%, followed by forests 33.3% and orchard 20%. Nymphs and adults cause damage to crop and orchard by sucking juice, outbreak of fungi through secretion of wax, and reduction of plant assimilation due to the nectar of nymphs. Also, it reduces the merchantable quality of fruits and thus causes economic damage. It is judged that M. pruinosa has been moved along major road via the traffic vehicles.

• Journal of Biosystems Engineering
• /
• 제22권4호
• /
• pp.487-496
• /
• 1997

A fuzzy logic controller(FLC) was developed for the autonomous travel of speedsprayer in an orchard. The autonomous travel with the FLC was graphically simulated under the conditions of an ordinary standard orchard. Differential global positioning system(DGPS) was used to find the direction of running and four ultrasonic sensors were used to detect obstacles during the running. The simulation results showed that the speedsprayer, by the FLC combined with DGPS and the ultrasonic sensors. could overcome the turning problem at comers which could not be solved with such a system as machine vision and might be operated autonomously.

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
• /
• pp.648-657
• /
• 1996

Autonomous speedsprayer operation in an orchard was conducted using a fuzzy logic controller (FLC). Orchard image analysis and signals of ultrasonic sensors were processed in real time. The speedsprayer was modified to be steered by two hydraulic cylinders. The FLC has two inputs of direction of running and distance from obstacles. Operation time of the hydraulic cylinders were inferred as output of the FLC. Field test results showed that the speedsprayer could be autonomously operated by the FLC along with the image processing and the ultrasonic sensors. The ultrasonic sensors didn't contribute to the improvement of guidance performance, but the speedsprayer could avoid trees or obstacles in emergent situations with them.

• Journal of Forest and Environmental Science
• /
• 제39권1호
• /
• pp.49-54
• /
• 2023

For unknown reasons, a few trees in a private chestnut orchard in Icheon si, Gyunggi-do suffered leaf chlorosis and growth decline. Based on symptoms, phytoplasma was a probable cause. Leaf samples were collected from two symptomatic and non-symptomatic trees in the orchard for phytoplasma detection. An amplicon of about 1.2 bp size was obtained from both symptomatic trees by PCR with the universal 16S rDNA primers. Sequences of these amplicons were found to have 99% nucleotide sequence identity to the corresponding genomic region of 16SrIII (X-disease group). More than 100 phytoplasma isolates, such as Candidatus phytoplasma pruni, Milkweed yellows phytoplasma, Goldenrod yellows phytoplasma, Tsuwabuki witches'-broom phytoplasma, Candidatus Phytoplasma trifolii, etc. were involved in the list. Phylogenetic analysis revealed that the sequence obtained in this study closely clustered with Candidatus phytoplasma groups. While one of the amplicons shared 91% identity with the Candidatus phytoplasma castaneae, the other shared only 47%. It needs further analysis and investigation to determine the exact taxonomy. Meanwhile, based on the analysis of the sequences, chlorosis, and small leaves were associated with phytoplasma.

• ETRI Journal
• /
• 제45권3호
• /
• pp.479-491
• /
• 2023

The automation of agricultural machines is an irreversible trend considering the demand for improved productivity and lack of labor in handling agricultural tasks. Unstructured working environments and weather often inhibit a seemingly simple task from being fully autonomously performed. In this context, we propose a remote driving system (RDS) to aid agricultural machines designed to operate autonomously. Particularly, we modify a commercial speed sprayer for orchard environments into a robotic speed sprayer to evaluate the proposed RDS's usability and test three sensor configurations in terms of human performance. Furthermore, we propose a confidence error ellipsebased task performance measure to evaluate human performance. In addition, we present field experimental results describing how the sensor configurations affect human performance. We find that a combination of a semiautonomous line tracking device and a wide-angle camera is the most effective for spraying. Finally, we discuss how to improve the proposed RDS in terms of usability and obtain a more accurate measure of human performance.

• 한국응용곤충학회:학술대회논문집
• /
• 한국응용곤충학회 2004년도 춘계 학술발표회
• /
• pp.90-90
• /
• 2004

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2002년도 총회 및 추계학술발표회
• /
• pp.70.3-71
• /
• 2002

• 한국환경생태학회:학술대회논문집
• /
• 한국환경생태학회 2004년도 학술대회지
• /
• pp.126-128
• /
• 2004

• 한국응용곤충학회:학술대회논문집
• /
• 한국응용곤충학회 2000년도 합동 춘계 학술발표회
• /
• pp.61-61
• /
• 2000