• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.160-160
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• 2007

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.440-446
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• 2019

Pine wilt disease occurred for the first time in Busan in 1988 and the damage has since been increasing. In 2005, a special law was enacted for pine wilt disease by Korea Forest Service. Incidences relating to the forest pest had been frequent and chemical control as well as physical control techniques had been applied to control it. Therefore, there is a need to reduce the damage caused by the pine wilt disease through intensive management such as continuous monitoring, control, and monitoring based on active control as well as management measures. In this study, the UAV-based monitoring method was proposed as an economical way of monitoring the forest pest. The efficiency of the existing method and UAV method had been analyzed, and as a result the study suggested that UAV can be used for forest pest monitoring and indeed improve efficiency. The UAV-based forest pest monitoring method has a cost reduction of about 50% compared with the conventional method and will also help to reduce the area where the survey was omitted.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.28-34
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• 2010

The spatial distribution characteristics of damaged trees by the pine wilt disease appear scattered spots spreading from single dead trees. That is the reason why it is difficult to early detect damage and to prevent from extensive damage. Thus, it is very important to forecast and analyze the damage occurrences, to establish strategies for prevention, and to supervise them. However, conventional survey which observes around roads or residential areas by naked eyes was impossible to investigate completely, missing target areas and dangerous areas. Therefore, aerial forecasting techniques on the damaged area were developed using GIS, GPS, and helicopters for an accurate observation of systematic and scientific approach in this study. Moreover, advantages of the techniques application were confirmed to survey 972 dead tree samples at 349 position-coordinates in 32 cities (about $28,810km^2$), 2005. This study is expected to apply widely to find dead trees and the causes, particularly by pine wilt disease.

• Journal of Digital Contents Society
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• v.18 no.1
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• pp.191-195
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• 2017

In this study, a smartphone application for reporting trees infected with pine wilt disease was developed to prevent the spread of the disease by the disease-carrying pests/insects, which is most damning to the country's pine trees, South Korea's representative tree species, and to ensure the sustained maintenance of the country's forest trees. Such application for handling information on the infected pine trees has three key components, as shown below. (1) Explanation of the pine wilt disease pests/insects, (2) Image capture of the infected pine tree, and transmission of its GPS location, (3) Inquiry on the neighboring area infected with pine wilt disease. It is possible to promptly provide the spatial information of the areas infected with pine wilt disease by developing a dedicated application for reporting trees infected with the disease based on GPS information. If users participate actively in the application and integration with the forest service application is to be realized, the application would be more actively utilized.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.251-260
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• 2022

Although the number of trees affected by pine wilt disease is decreasing, the affected area is expanding across the country. Recently, with the development of deep learning technology, it is being rapidly applied to the detection study of pine wilt nematodes and dead trees. The purpose of this study is to efficiently acquire deep learning training data and acquire accurate true values to further improve the detection ability of U-Net models through learning. To achieve this purpose, by using a filtering method applying a step-by-step deep learning algorithm the ambiguous analysis basis of the deep learning model is minimized, enabling efficient analysis and judgment. As a result of the analysis the U-Net model using the true values analyzed by period in the detection and performance improvement of dead pine trees of wilt nematode using the U-Net algorithm had a recall rate of -0.5%p than the U-Net model using the previously provided true values, precision was 7.6%p and F-1 score was 4.1%p. In the future, it is judged that there is a possibility to increase the precision of wilt detection by applying various filtering techniques, and it is judged that the drone surveillance method using drone orthographic images and artificial intelligence can be used in the pine wilt nematode disaster prevention project.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.307-313
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• 2003

Japanese pine sawyer, Monochamus alternatus, is a primary vector of pinewood nematode, Bursaphelenchus xylophilus in Korea. Emergence characteristics of the adults were studied in Jinju, Korea using dead pine logs in which the larvae of the sawyer overwintered from 1999 to 2002. Emergence data showed that the adults began to emerge out of the logs in sunny place from May the 15th in average of the four years. Cumulative emergence ratio (CER) reached at 50% at mid-June, and the emergence terminated by early or late July depending on years. In shady place, however,50% CER was reached 17 days later than in sunny place. The 50％ CER of males reached 1 to 4 days earlier than that of females depending on years. Of the adults emerged from the logs collected from February to April in 2001, 97.6％ was univoltine, and the rest was biennial which emerged from May to July of the next year. Female and male adults emerged throughout 24 hours; 32.3% of the total adults emerged from 8 to 12 a.m. It took 68.0 seconds for the adults to escape from pine logs.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.486-496
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• 2018

Pine wilt disease (PWD) in Gyeonggi province was first detected in Gwangju in 2007, and ever since has caused extensive damage. Insect vector and host tree in Gyeonggi province are Monochamus saltuarius and Pinus koraiensis, respectively, which are different from the southern region that consist of Monochamus alternatus and Pinus densiflora. Consequently, spread and mortality characteristics may be different, but our understanding is limited. In this research, we utilized the spatial data of newly infected trees in Gyeonggi province from 2008 to 2015 to analyze how it is related to various environmental and human factors, such as elevation, forest type, and road network. We also analyzed the minimum distance from newly infected tree to last year's closest infected tree to examine the dispersal characteristics based on new outbreak locations. Annual number of newly infected trees rapidly increased from 2008 to 2013, which then stabilized. Number of administrative districts with infected trees was 5 in 2012, 11 in 2013, and 15 in 2014. Most of the infected trees was Pinus koraiensis, with its proportion close to 90% throughout the survey period. Mean distance to newly infected trees dramatically decreased over time, from 4,111 m from 2012 to 2013, to approximately 600 m from 2013 to 2014 and 2014 to 2015. Most new infections occurred in higher elevation over time. Distance to road from newly infected trees continuously increased, suggesting that natural diffusion dispersal is increasingly occurring compared to human-influenced dispersal over time.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.170-175
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• 2013

This study was conducted to investigate the effect on the habitation of Monochamus alternatus, a vector insect of Pine wood nematode by the tended sound stumps for the developing forestry control methods of Pine wilt disease controls. Field cage plots (1 m ${\times}$ 1 m ${\times}$ 1 m) were established 12 units (Experiment1:4 units, Experiment2:8 Units) and were treated 4 kinds(February in 2010, February, April, June in 2011). The adults of M. alternatus were put into 4~5couples each the cage June in 2011. Presence or absence of the larva entrance holes and larva were detailed November in 2011. The larva were appeared in the sound stumps of sapling and young trees tended at February, April, June, the current emergence year of M. alternatus, but were not appeared in the sound stumps of sapling and young trees tended February in 2010, one year before the emergence of M. alternatus. The larva habitated in stumps of sapling were likely to be smaller in size in compare to the larva in stumps of young trees. In case of young tree, the larva were found at the cleft part of bark, but were not found at ridge part of bark. All observed larva appeared at part of bark and between the bark and the woody parts, but were not found at the woody parts. To develop the control guiding principal of sound stump after forest tending practice, further experiment need is in existence oviposition and larvae of vectors by height of stemps.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.499-505
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• 2013

Pine wilt disease has known as a serious forest disease in East Asia such as Japan, Korea and China. Fumigation and burning are considered as best way to treat infected tree at early detection. For investigate spectral reflectance characteristics of infected trees, periodic measurement has been done in both infected and non-infected trees. Infected and non-infected trees' reflectance (400 nm~2,500 nm wavelength) are detected from June to October with GER3700 spectrometer. Noise of reflectance data was corrected using cubic spline interpolation method. Reflectance was changed in most of infected trees with ranges Red (600 nm~700 nm) and Middle Infrared (1,400 nm~1,500 nm) within two months after injected by Pine Wood nematode (PWN), but there was no differences in non-infected trees. Infected and non-infected trees were compared statistically in each period. As a result, we found that a statistically significant difference was occurred at Red and Middle Infrared (MIR) 2 months after injection (p<0.05), however, no significant difference in near infrared (p>0.05). Therefore, the early detection of infested pine trees by PWN may possible through detecting the change of spectral reflectance at red and MIR.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.41-48
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• 2008

The required energy for the heat treatment of pine log was evaluated in this study. A proper heat treatment of pine log infected by pinewood nematode (Bursaphelenchus xylophilus) can prevent spreading of the infection by pinewood nematode and make the infected pinewood valuable again. The FAO (Food and Agriculture Organization of the United Nations) heat treatment standard for various types of infected wood for which a heat treatment of the core part of the wood is necessary is 30 minutes at $56^{\circ}C$, taking into account the international standards for phytosanitary measures (ISPM No. 15). In this study, the energy consumption during the heat treatment was separated into two kinds of energy, initial energy for heating kiln drier and to reach set point temperature and relative humidity and the required energy supplementing heat loss. The initial required energy per unit time is greater than that during the treatment. The energy consumption per unit time varied little during the heat treatment. As a result, the set point relative humidity with set dry bulb temperature and density of wood dependent on moisture content are very important factors to change energy consumption in the experiment. The heat treatment at higher temperature and higher humidity levels requires more energy consumption but less treatment time. It is expected that a more effective energy program could be planed for the heat treatment of pine log through this study.