• Korean journal of applied entomology
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• v.61 no.4
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• pp.639-640
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• 2022

A Ypsolophid moth Saridoscelis sphenias Meyrick was recorded in 2020 first in Korea, and specimens were collected from Jindo and Wando in Jeonam province from 2016 to 2017. This moth uses host plants such as Pieris japonica (Thunb.) D. Don ex G. Don, Vaccinium bracteatum Thunb. and Leucothoe grayana Maxim. var oblongifolia (Miq.). This species was discovered once in a blueberry orchard in Jeju in August 2014, and since then it has been regarded as not an established species because of no further detection. However, S. sphenias was found again in blueberry orchards grown in vinyl houses in Jeju city and Seogwipo city in 2018 and 2019. Since 2020, this pest has also been found on field-grown blueberries. Hatched larvae first bored into new shoots and fed inside, and the mid-aged larvae escaped from the inside of shoots, attached several shoots with webs, and fed on the leaves in the group. It is considered that S. sphenias will become a severe pest on blueberries; thus, we report the basic life cycle here.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.468-468
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• 2021

도시의 개발은 불투수면의 증가, 토지이용의 변화, 용수 수요 증가를 초래하였고, 최근에는 기후변화 양극화 현상으로 도심내 물순환체계를 더욱 왜곡시키는 문제를 초래하였다. 1962년부터 서울의 도심지가 본격적으로 개발되기 시작하면서 7.8%였던 불투수율이 2010년에는 50%까지 증가하였다. 토지의 피복상태가 숲과 흙일 때는 강우의 10%는 하천으로, 토양 흡수는 50%, 증발이 40%가량 된다. 보통 토양에 흡수된 물은 토양층에서 머물렀다가 중간유출되어 하천으로 유입되거나 지하수로 전환된다. 그러나 개발로 인하여 아스팔트나 콘크리트로 포장된 경우 55%가 하천으로 유입되고 토양으로 흡수되는 양은 15% 정도로 강우가 급격하게 유출되어 빠져나가 버린다. 도시 불투수면적의 증가는 단순히 치수와 이수의 문제뿐만 아니라 도심의 하천 및 녹지공간에 조성되어 있는 생태계 유지에 필요한 최소한의 수량인 생태용수 확보마저 위협하고 있다. 도심 하천의 환경생태유량 확보는 하천의 정상적인 기능을 유지할 뿐만 아니라 하천의 자정 능력을 향상하며, 수생생물의 서식환경을 보존에 기여하므로 도심의 자연성 회복에 있어 매우 중요하다. 도시 생태환경은 녹지의 단절과 파편화로 연속성을 확보하지 못하고 있는데, 이렇게 단절되고 파편화된 생태계를 연결하여 생태축을 확보하면 도시 생태계의 건강성을 증진시킬 수 있다. 대부분의 도시에서 관리하고 있는 가로수 및 띠녹지 등 녹지공간(그린 네트워크, Green Network)을 활용하여 수원 함양이나 수질정화 기능(블루 네트워크, Blue Network)을 부여하면 녹지와 수자원을 연결한 그린-블루 네트워크를 형성하여 도시 생태용수확보에도 기여할 뿐만 아니라 나아가 도심 하천의 자연성 회복에도 기여할 것으로 기대된다. 본 연구는 도시의 가로수와 띠녹지를 활용하여 빗물저장 기능과 침투기능을 확대하기 위해 기존에 녹지 및 공원 관리 차원에서 가로수 도시계획이 수립되고 관련 사업이 진행되어 온 현행 제도상의 문제점을 검토하여 제도적 개선 방안을 제안하는 것에 목적을 둔다.

• Korean Journal of Optics and Photonics
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• v.35 no.2
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• pp.49-60
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• 2024

We analyze the number of phase screens required for the simulation of a high-energy laser beam's propagation over an atmospheric channel. For high-energy lasers exceeding tens of kilowatts (kW) in power, the laser beam is mainly affected by atmospheric turbulence and thermal blooming. When using the split-step method to implement losses due to atmospheric absorption and scattering and distortion of the beam due to turbulence and thermal blooming, the number of phase screens is a critical factor in determining the accuracy and time required for the simulation. By comparing simulation results obtained using a large number of phase screens (e.g., 150 screens) under a wide range of atmospheric turbulence conditions, we provide new guidelines for the number of phase screens required for simulating the beam propagation of a high-power laser below 2.5×10⁶ W/m² (e.g., a 500-kW laser beam having a 50-cm diameter).

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.695-702
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• 2017

This study was carried out to investigate the effects of seed vinegar on antioxidant activity and antimicrobial activities of concentrated blueberry vinegar (CBV). Of the nine strains of yeast and six strains of acetic acid bacteria provided by the Microbial Institute for Fermentation Industry, each strain of yeast (Saccharomyces cerevisiae SRCM 100610, showing the highest ethanol content) and acetic acid bacteria (Acetobacter pasteurianus SRCM 101342, showing the highest total acidity) was selected for production of CBVs. Sugar content, pH, total acidity, total phenolic content (TPC), and browning intensity (280 nm and 420 nm) in CBVs using concentrated blueberry juice were $11.05{\sim}12.70^{\circ}Brix$, 2.63~2.98, 1.65~5.72%, 3.03~4.24 mg/mL, 0.95~1.50, and 0.11~0.20, respectively. Sugar content and total acidity of CBVs increased upon addition of seed vinegar, whereas pH, TPC, and browning intensity decreased. Of all CBVs with various additions of seed vinegar, the control showed the lowest $EC_{50}$ values in DPPH radical scavenging assay, ABTS radical scavenging assay, and reducing power (23.80, 19.48, and 79.21 dilution factor, respectively), whereas the 40% seed vinegar group showed the highest clear zone diameter values for Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus (4.31, 4.59, 5.81, and 3.97, respectively). Antioxidant activities of CBVs were closely correlated with their TPC, browning intensity at 280 nm, pH, and total acidity values, showing correlation determination coefficient ($R^2$) values higher 0.82. However, antimicrobial activities of CBVs were closely correlated with their pH and total acidity values, showing higher $R^2$ values more than 0.92. These results suggest that CBVs using concentrated blueberry juice, S. cerevisiae SRCM 100610, and A. pasteurianus SRCM 101342 may be useful as potentially functional foods for enhancing health.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.166-176
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• 2015

Research was initiated to investigate root growth characteristics of major cool-season grasses (CSG) and to collect basic information useful for sports turf design, construction and maintenance. Several turfgrasses were evaluated in the USGA (United States Golf Association) soil system. Turfgrass entries were comprised 3 blends and 3 mixtures of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.). Significant differences were found in root growth, rooting potential and rooting development. These characteristics increased with time after seeding, but varied with establishment stages. In early stage, root length was highest with PR, intermediate with TF and lowest with KB. Evaluation in a middle stage indicated that root growth was similar to early-stage evaluation, but decreased by 13 to 31% compared with early-stage values. Root growth of late stage increased by 34 to 85% over middle-stage root growth. Overall, thhere was not much difference in root length among treatments, with all except Mixture I reaching 22cm in root length. Rooting potential ranking was variable with establishment stage, being PR > KB > TF in early stage, PR > TF > KB in middle stage and TF > PR > KB in late stage. At the end of the study, TF was rated best for rooting development, followed by PR and finally KB. Our results showed that TF was the best species in regard to overall rooting characteristics. TF exhibited excellent rooting development with time after establishment. Bunch-type PR showed fast root growth in the early stage, but rooting quality characteristics decreased with time, especially for rooting development. By contrast, rhizomatous-type KB was poor in early-stage root growth, but rooting characteristics improved with time after establishment. These variations in rooting characteristics among CSGs were considered to arise from differences in establishment vigor, growth habit and genetic characteristics. Information on root growth, rooting potential and rooting development by establishment stages will be useful for sports turf design, construction and maintenance.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.79-88
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• 2011

The purpose of this study was to obtain information on rates and salinity levels of irrigation for growth of Kentucky bluegrass by minimizing the hazard of salt accumulation in the sand based growing medium. Root zone profile consists of 20 cm sand based top soil, 20 cm of coarse sand as layer to interrupt capillary rise and 10 cm of reclaimed paddy soil as a base of the root zone profile. Topsoil was a mixture of dredged sand and peat with a ratio of 95%: 5% by volume. The columns were soaked into 5 cm depth saline water reservoir with salinity level of 3-5 $dSm^{-1}$. Salinity levels of irrigation water were 0, 2 and 3 $dSm^{-1}$. Irrigation rates were 3.8, 5.7 and 7.6 mm $day^{-1}$ which were equivalent to 70%, 100% and 130% of average ET (evapotranspiration) rate of Kentucky bluegrass, and irrigation interval was 3 days. Salt accumulation was due to irrigated water and moved up water from shallow water base. At the end of second year, the accumulation of salt in the rootzone showed ECc of3.86, 4.7 and 5.1 $dSm^{-1}$, and SAR of 19.2, 23.9 and 27.5 when the salinities were 0, 2 and 3 dS $m^{-1}$, respectively. Irrigation rates of 100% and 130% of ET rate with saline water did not decrease ECe and SAR in growing media. The growth of KEG was influenced by irrigation rate in the $1^{st}$ year, however, salinity level was more critical in the $2^{nd}$ year. Compared to non-saline water, saline water of 2 and 3 dS $m^{-1}$ resulted in decreased visual quality by 3.2% and 16.5%, by 6.4% and 39.3% in clipping weight, and by 5.5% and 5.0% in root mass, respectively.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.208-216
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• 2011

The purpose of this study was to find soil-amendment materials those support the growth of Kentucky bluegrass and reduce salt accumulation at the sand based growing media in saline conditions. Rootzone profile in columns consisted of 20 cm of top soil, 20 cm coarse sand as capillary rise interruption layer and 10 cm reclaimed paddy soil as the base of the profile. Top soils were mixtures of dredged sand (DS) and amendment with compositions of 90% sand + 10% peat moss (SP), 80% sand + 10% soil + 10% bottom ash (SSoBa), 80% sand + 20% soil (SSo), 90% sand + 5% peat + 5% zeolite (SPZ), and 80% sand + 20% bottom ash (SBa). The top soil mixtures of DS and amendments were treated with and without gypsum (Gp). The columns were soaked into 5 cm depth saline water reservoir with the salinity level of $3-5dSm^{-1}$. Irrigation of $2dSm^{-1}$ saline water with rate of $5.7mm\;day^{-1}$ was applied by 3 day interval. Application of zeolite decreased SAR, application of gypsum decreased ECe of the sand amended by peat + zeolite and decreased the SAR of sand amended by bottom ash. The SP and SSoGp resulted in higher clipping dry weight of Kentucky bluegrass. The SSoGp and SPZGp showed longer root lengths. The SP and SBaGp showed higher visual quality. Addition of gypsum to soil and bottom ash treatments resulted in the increased shoot growth, whereas additional gypsum to the treatments of peat, soil and zeolite increased the root growth of Kentucky bluegrass.

• Journal of Life Science
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• v.32 no.7
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• pp.578-587
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• 2022

Korea, as the world's 7^th largest emitter of greenhouse gases, has raised the national greenhouse gas reduction target as international regulations have been strengthened. As it is possible to utilize coastal and marine ecosystems as important nature-based solutions (NbS) for implementing climate change mitigation or adaptation plans, the blue carbon ecosystem is now receiving attention. Blue carbon refers to carbon that is deposited and stored for a long period after carbon dioxide (CO₂) is absorbed as biomass by coastal ecosystems or oceanic ecosystems through photosynthesis. Currently, there are only three blue carbon ecosystems officially recognized by the Intergovernmental Panel on Climate Change (IPCC): mangroves, salt marshes, and seagrasses. However, the results of new research on the high CO₂ sequestration and storage capacity of various new blue carbon sinks, such as seaweeds, microalgae, coral reefs, and non-vegetated tidal flats, have been continuously reported to the academic community recently. The possibility of IPCC international accreditation is gradually increasing through scientific verification related to calculations. In this review, the current status and potential value of seaweeds, seagrass fields, and non-vegetated tidal flats, which are sources of blue carbon on the east coast, are discussed. This paper confirms that seaweed resources are the most effective NbS in the East Sea of Korea. In addition, we would like to suggest the direction of research and development (R&D) and utilization so that new blue carbon sinks can obtain international IPCC certification in the near future.

• Asian Journal of Turfgrass Science
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• v.17 no.1
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• pp.1-12
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• 2003

Research was Initiated to investigate germination characteristics of cool-season grasses (CSG). Several turfgrasses were tested in different experiments. Experiments I and III were conducted under a room temperature condition of 16$^{\circ}C$ to 23 $^{\circ}C$ and under a constant light condition at 25 $^{\circ}C$, respectively. An alternative environment condition that is a requirement for a CSG germination test by International Seed Testing Association (ISTA) was applied in the Experiment II, consisting of 8-hr light at 25 $^{\circ}C$ and 16-hr dark at 15 $^{\circ}C$. In each experiment, data such as early germinating vigor, germination speed and germination rate were evaluated. Six turfgrass entries were comprised of two varieties each from Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.), respectively. Significant differences were observed in early germinating vigor, germination speed and germination rate. Early germinating vigor as measured by days to 70% seed germination was variable according to environment conditions, turfgrasses and varieties. It was less than 6 days in PR and 6 to 9 days in TF. However, KB resulted in 11 to 13 days under an alternative condition and 11 to 28 days under a room temperature condition. The germination speed was fastest in PR of 7 to 10 days and slowest in KB of 14 to 21 days. However, intermediate speed of 10 to 14 days was associated with TF. There were considerable variations in germination rate among turfgrasses according to different conditions. Generally, PR and TF germinated well, regardless of environment conditions. However, a great difference was observed among KB varieties, when compared with others. Under a room temperature condition, total germination rate was 71.0% in Midnight and 77.7% in Award. And it increased under an alternative condition, which was 81.7% and 91.7% in Award and Midnight, respectively. However, the poorest rate was found under a constant temperature condition, resulting in 18.0% in Award and 15.3% in Midnight. These results suggest that an intensive germination test required by ISTA be needed prior to the decision of seeding rate, including early germinating vigor and germination speed as well as total germination rate. KB is very sensitive to environment conditions and thus its variety selection should be based on a careful expertise.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.2
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• pp.33-42
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• 2004

Controlling household devices using an infra-ray (IR) has a limitation since the IR signal cannot only be extended, but also cannot be transmitted over the physical barrier. Using a radio frequency (RF) may overcome these shortcomings. Bluetooth is one of the emerging RF_based standard protocols for short-range wireless communications among various control devices. In this paper, we describe a control system for household appliances using Bluetooth under embedded Linux environment. The control system consists of a centralized main controller and geographically scattered wallplates. Some of the challenges and lessons learned will be outlined in the presentation. As a result of this research, we found that the Bluetooth is a promising technology for realizing wireless control systems for household appliances.