• Korean journal of applied entomology
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• v.29 no.3
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• pp.209-215
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• 1990

Some preliminary studies were conducted to find out whether the levee-burning could justifiable for the suppression of insect pests, particularly the smaller brown planthopper (Laodelphax striatellus F.). Density surveys on pests and their enemies (mostly spiders) were carried out upto the mid May at an experimental paddy field located in Suwon after of it's levee $(72\times1m)$ was burned on Feb. 20, 1987. Results were discussed in relation to density recovering of both pests and their possible enemies (spiders) and summarized as below. Not a single individual of any pest or enemy was found from the levee upto sometime after the levee-burning. Grasses started to grow more vigorously in burned ares than in unburned upto about 60 days after the burning. And densities of both pest and enemies grew higher in burned areas than in unburned from about 75 days after the burning (in Early may). It is suspected that all individuals of pests and enemies fond from the burned areas could have immigrated from the surrounding areas. If levee-burning was carried out in much wider areas, much longer time would be needed to recover the density of both pests and enemies to the center region of the burning. Wingless spiders would require even longer time than winged pest species to re-establish in the center region of the widely burned field. Pirata subpiraticus, the most abundant spider species in Korean paddy fields, starts to move about and searches for food at above $9^{\circ}C$ which is somewhat lower than the critical temperature for the pest species. Thus P. subpiraticus would require more food than other pest species early in the spring, and therefore, it would have lower probability to survive than pest species particularly in burned areas. Experiments for pest suppression with levee-burning would better be carried on in much wider areas, and its justification seems to be discussed after man other disciplines related to both pests and their natural enemies were throughly studied together with their density surveys. However, according to the present point of vie, the opinion that levee-burning is helpful for controlling pests which over winter on levee areas could not be justifiable.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.208-217
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• 2023

Accurate estimation of dormancy breaking and first bloom dates is crucial for effective fire blight control by disease model such as Maryblyt in apple orchards. The duration from dormancy breaking to first bloom in apple trees was influenced by daily minimum temperatures during the dormant period. The purpose of this study is to investigate the relationship between minimum temperatures during this period and the time taken for flowering to commence. Webcam data from eight apple orchards, equipped by the National Institute of Horticultural and Herbal Science, were observed from 2019 to 2023 to determine the dates of starting bloom (B1). Additionally, the dormancy breaking dates for these eight sites were estimated using an apple chill day model, with a value of -100.5 DD, based on collected weather data. Two regressions were performed to analyze the relationships: the first regression between the number of days under 0℃ (X₁) and the time from calculated dormancy breaking to observed first bloom (Y), resulting in Y = 0.87 × X₁ + 40.76 with R² = 0.84. The second regression examined the starting date of breaking dormancy (X₂) and the duration from dormancy breaking to observed first bloom (Y), resulting in Y = -1.07 × X₂ + 143.62 with R² = 0.92. These findings suggest that apple anti-chill days are significantly affected by minimum temperatures during the period from dormancy breaking to flowering, indicating their importance in fire blight control measures.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.301-307
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• 2005

The morphology of the high burnup $UO_2$ spent fuel, which was oxidized and annealed in a PIA (Post Irradiation Annealing) apparatus, has been observed. The high burnup fuel irradiated in Ulchin Unit 2, average rod burnup 57,000 MWd/tU, was transported to the KAERI's PIEF. The test specimen was used with about 200 mg of the spent $UO_2$ fuel fragment of the local burnup 65,000 MWd/tU. This specimen was annealed at $1400^{\circ}C$ for 4hrs after the oxidation for 3hrs to grain boundary using the PIA apparatus in a hot-cell. In order to oxidize the grain boundary, the oxidation temperature increased up to $500^{\circ}C$ and held for 3hrs in the mixed gas (60 ml He and 100 ml STD-air) atmosphere. The amount of 85Kr during the whole test process was measured to know the fission gas release behavior using the online system of a beta counter and a gamma counter. The detailed micro-structure was observed by a SEM to confirm the change of the fuel morphology after this test. As the annealing temperature increased, the fission products were observed to move to the grain surface and grain boundary of the $UO_2$ matrix. This specimen was re-structured through the reduction process, and the grain sizes were distributed from 5 to $10\;{\mu}m$.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.27-35
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• 2007

The majority of farm managers growing the garden products in greenhouse concern massively about the diagnosis and prevention of the breeding and extermination for pests. especially, the managing problem for pests turns up as main issue. In the paper, we first build a wireless sensor network with soil and environment sensors such as illumination, temperature and humidity. And then we design and implement multimedia pest predication and management system which is able to predict and manage various pest of garden products in greenhouse. The proposed system can support the database with information about the pests by building up wireless sensor network in greenhouse compared with existing high-priced PLC device as well as collect various environment information from soil, the interior of greenhouse, and the exterior of greenhouse. To verify the good capability of our system, we implemented several GUI interface corresponding desktop. web, and PDA mobile platform based on real greenhouse model. Finally, we can confirm that our system work well prediction and management of pest of garden products in greenhouse based on several platforms.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1353-1369
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• 2023

In the event of a disaster accident at sea, the scale of damage will vary due to weather effects such as wind, currents, and tidal waves, and it is obligatory to minimize the scale of damage by establishing appropriate control plans through quick on-site identification. In particular, it is difficult to identify pollutants that exist in a thin film at sea surface due to their relatively low viscosity and surface tension among pollutants discharged into the sea. Therefore, this study aims to develop an algorithm to detect suspended pollutants on the sea surface in RGB images using imaging equipment that can be easily used in the field, and to evaluate the performance of the algorithm using input data obtained from actual waters. The developed algorithm uses image enhancement techniques to improve the contrast between the intensity values of pollutants and general sea surfaces, and through histogram analysis, the background threshold is found,suspended solids other than pollutants are removed, and finally pollutants are classified. In this study, a real sea test using substitute materials was performed to evaluate the performance of the developed algorithm, and most of the suspended marine pollutants were detected, but the false detection area occurred in places with strong waves. However, the detection results are about three times better than the detection method using a single threshold in the existing algorithm. Through the results of this R&D, it is expected to be useful for on-site control response activities by detecting suspended marine pollutants that were difficult to identify with the naked eye at existing sites.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.250-256
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• 1996

In order to estimate production cost of rice per ha of large farm, a detail survey of 104ha farm was made in 1994. Amount of labor input and labor cost per ha was calculated as 270, 000won and 108hours. Direct production cost of the farm was 1, 092, 000won(l00) and was lower than that of average farms 2, 067, 000won(189) in Korea. But it still was higher than that of Sac1amento farms 717, 000won(66) and that of Buter Area's, 845, 000won(77). It seems feasible to cut down the cost about 10~15% provided the labor and machinery may be used more efficiently. Some cost down may also be possible on marketing and processing sectors. Therefore it may not be pessimistic in competing with U.S. rice farms if we establish 100ha size well managed and arranged farms in Korea.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.694-700
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• 2018

Korea has disposed of medium and low level radioactive waste generated by operating nuclear power plants permanently through the radioactive waste repository located in Gyeongju. However, the maritime transport of radioactive waste is exposed to the risk of marine accidents, and it will be necessary to introduce a system to secure safety from the viewpoint of the function and role of the Korea Coast Guard. Especially, Korea is affected by large-scale marine accidents, such as the Hebei Spirit or Sewol accidents. From this point of view, we analyzed the current status of Korea radioactive waste shipping and examined the response systems of major foreign countries. As a result of examining major cases of accidents, we have operated an Emergency Towing Vessel (ETV) fleet centering on European countries in order to respond urgently to marine casualties that may have social, regional and international effects, such as accidents of similar nuclear material carriers and dangerous cargo ships. It proves a partial effect. Based on this, we propose the introduction of the Korean ETV System. In other words, it is necessary to respond to large-scale marine accidents that could lead to enormous environmental, property, and personal damage, such as marine accidents involving nuclear material ships, large oil tankers, and large passenger ships. For this, it seems necessary to introduce Korea ETV, which can carry out emergency towing, oil pollution control function, large - scale rescue equipment and manpower. This will lead to the enhancement of the Korea Coast Guard response to marine accidents, and will not miss the golden time of the initial response to the national disaster, which will help protect precious people, property and the environment.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.135-143
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• 2021

Aerospace and geospatial technologies have become more accessible by researchers and agricultural practitioners, and these technologies can play a pivotal role in transforming current pest management practices in agriculture and forestry. During the past 20 years, technologies including satellites, manned and unmanned aircraft, spectral sensors, information systems, and autonomous field equipment, have been used to detect pests and apply control measures site-specifically. Despite the availability of aerospace and geospatial technologies, along with big-data-driven artificial intelligence, applications of such technologies to apple IPM have not been realized yet. Using a case study conducted at the Korea Apple Research Institute, this article discusses the advances and limitations of current aerospace and geospatial technologies that can be used for improving apple IPM.

• Journal of agricultural medicine and community health
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• v.48 no.4
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• pp.239-250
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• 2023

Objective: This study was a preliminary study for the prevention programs for farmers' occupational diseases. It selected the priorities recognized by farmers, such as occupational diseases, and also identifies the effectiveness and feasibility of prevention programs among diseases recognized by farmers. Therefore, we plan to use it as basis data for future farmer safety and health programs. Method: The subjects of the study were farmers living in the region, selected through a snowball recruitment method, and a total of 671 people were targeted. The priority selection method was the Basic Priority Rating System (BPRS) method, and among the occupational diseases, programs to prevent musculoskeletal diseases, cardiovascular and respiratory diseases, and pesticide poisoning were surveyed on the effectiveness and feasibility of farmers. Results: Among occupational diseases, the highest priority was musculo-skeletal disease, followed by respiratory disease and pesticide poisoning. Among the programs for musculoskeletal disease, 'use of agricultural work convenience equipment and auxiliary tools' had the highest perceived effectiveness and feasibility. Among the five programs for pesticide poisoning, 'equipment of protective equipment such as pesticide protective clothing/glove' had the highest effectiveness at 67.4%, and 'compliance with pesticide use instructions' had the highest level of feasibility at 64.3%. Among the four programs to prevent respiratory diseases, 'wearing a dust mask or gas mask' was the highest at 65.5% in terms of both effectiveness and feasibility. Conclusion: When carrying out safety and health programs for farmers, the priorities recognized by farmers should be taken into consideration, and the program contents should also be developed taking into account the size of effect and feasibility recognized by farmers.

• Journal of Preventive Medicine and Public Health
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• v.42 no.2
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• pp.89-95
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• 2009

Objectives : To assess the protective effects of wearing protective devices among the residents and volunteers who participated in the cleanup of the Hebei Spirit oil spill. Methods : A total of 288 residents and 724 volunteers were surveyed about symptoms, whether they were wearing protective devices and potential confounding variables. The questionnaires were administered from the second to the sixth week following the accident. Spot urine samples were collected and analyzed for metabolites of 4 volatile organic compounds(VOCs), 2 polycyclic aromatic hydrocarbons(PAHs), and 6 heavy metals. The association between the wearing of protective devices and various symptoms was assessed using a multiple logistic regression adjusted for confounding variables. A multiple generalized linear regression model adjusted for the covariates was used to test for a difference in least-square mean concentration of urinary biomarkers between residents who wore protective devices and those who did not. Results : Thirty nine to 98% of the residents and 62-98% of volunteers wore protective devices. Levels of fatigue and fever were higher among residents not wearing masks than among those who did wear masks(odds ratio 4.5; 95% confidence interval 1.23-19.86). Urinary mercury levels were found to be significantly higher among residents not wearing work clothes or boots(p<0.05). Conclusions : Because the survey was not performed during the initial high-exposure period, no significant difference was found in metabolite levels between people who wore protective devices and those who did not, except for mercury, whose biological half-life is more than 6 weeks.