• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.95-104
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• 1999

Comparative biodegradation studies of liquid and solid alkanes and of two different solid alkanes were conducted by an isolated Acinetobacter sp., which degraded crude oil alkanes simultaneously. for the determination of degradation mechanism of hydrophobic crude oil constituents. Also a model oil experimental system composed of a solid alkane. heneicosane, as a substrate and a non-degradable non-aqueous phase liquid. pristane, as an oil matrix was established and studied. It was proposed that the Acinefobacter sp. utilized hydrophobic substrates directly on the surface of them with no difference in the degradation rates between the liquid and solid alkanes. On the basis of the results from the heneicosane/pristane system which imitates crude oil matrix containing solid constituents. the crude oil matrix was considered to reduce the bioavailability of contained substrates by reducing the specific surface area of substrates to contact with microorganisms.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.472-472
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• 2011

탁도는 물의 상대적인 흐림 정도를 나타내는 척도로서 이는 빛이 물을 통과할 때 산란시키는 부유고형물질 때문에 발생한다. 토양침식에 의하여 지표수로 유입된 토사와 광물질은 하천의 수송 및 퇴적 과정을 거치며 이동한다. 이때 하상 퇴적물은 바닥으로부터 먹이를 찾는 유기체에 의해 뒤섞이며 입자들은 일정기간동안 물의 흐름에 의해 부유상태로 남아 있게 되고, 유입되는 영양소와 빛에 의하여 성장하는 조류 또한 탁도를 증가시키는 원인이 된다. 이러한 부유물질의 증가는 수중에 태양복사에너지 전달을 방해하여 수중생태계의 먹이사슬과 저서생물의 서식환경에 많은 영향을 미치고, 수표면 온도 또한 태양으로부터 열을 흡수하는 표면 근처의 부유물질에 의해 증가하여 용존산소의 양에도 영향을 미친다. 따라서 수체내 분포하고 있는 부유물질의 종류와 양 및 공간적 분포 파악은 수질문제와 재난 예방 및 생물의 서식환경 문제를 파악하고 해결하는 데 매우 중요하다. 그러나 부유물질에 부착되어 있는 영양소, 금속, 살충제 등은 물 순환 시스템을 통하여 끊임없이 운반되고 상류유역의 흐름 조건에 따라 시공간적으로 변화하기 때문에 이를 규명하는 것이 매우 어려운 실정이다. 이러한 문제를 해결하기 위하여 광역적인 탁수환경의 분석방법으로 원격탐사(Remote Sensing, 이후 RS) 기법을 이용한 방법이 제안되고 있다. 이미 선진국에서는 광역수계의 수질관리를 위해 RS 기법을 이용하여 신속하고 정확한 수질상태 파악을 시도하고 있으며, 우리나라에서도 KOMPSAT 발사를 계기로 RS 관련 기술이 비약적으로 진화하고 있다. 그러나 RS 데이터를 활용하는데 필수적인 분광학적 특성 규명에 대한 연구는 대부분 식생과 토양에 한정되어 있으며 수체에 대한 연구는 현장조사의 어려움으로 인하여 상당히 제한적인 수준이다. 따라서 본 연구에서는 탁도의 변화에 따른 분광반사 특성을 휴대용 분광복사계를 이용하여 규명하고, 이를 Landsat 위성영상에 적용하여 새만금 유역을 대상으로 완공 직후인 2006년부터 2010년까지의 탁수환경을 모니터링 하였다. 그 결과 새만금 유역 탁수환경을 정성적으로 확인할 수 있었으며, 이를 이용하여 탁수환경 연구에 RS 기법이 효과적임을 제시하고자 한다.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.217-223
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• 2010

This study was conducted to reclassify Dongsong series based on the second edition of Soil Taxonomy and to discuss the formation of Dongsong series distributed on the lava plain at Cheolweon in Korea. Morphological properties of typifying pedon of Dongsong series were investigated, and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Dongsong series has brown (7.5YR 4/2) silty clay loam Ap horizon (0-16 cm), brown (7.5YR 4/2) silty clay loam BA horizon (16-22 cm), brown (7.5YR 4/2) silty clay Bt1 horizon (22-50 cm), reddish brown (5YR 5/4) silty clay Bt2 horizon (50-92 cm), and brown (7.5YR 4/3) silty clay loam Bt3 horizon (92-120 cm). It occurs on lava plain derived from baslt materials. The typifying pedon has higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to more than 120 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Andisol or Alfisol. It has aquic conditions for some time in normal years in one or more horizons within 50 cm of the mineral soil surface, redoximorphic features between a depth of 25 cm, and a depth of 40 cm from the mineral soil surface, and redox concentrations, and 50%or more redox depletions with chroma of 2 or less in the matrix within the upper 12.5 cm of the argillic horizon. Therefore it can be classified as Aquult. It has episaturation, and keys out as Epiaquult. It has 50% or more chroma of 3 or more in one or more horizons between a depth of 25 cm from the mineral soil surface, and a depth of 75 cm. It can be classified as Aeric Aquult. Dongsong series have 35%or more clay at the particle-size control section, and have mesic soil temperature regime. Therefore they can be classified as fine, mesic family of Aeric Epiaquults, not as fine, mesic family of Typic Epiaqualfs. The Quarternary volcanic activities occurred in Jeju Island, Ulrung Island, Baekryeong Island, Cheolweon area, and Mt. Paekdu et al. in the Korean Penninsula. Most of them belong to the central eruption type, but Cheolweon area may be of the fissure eruption type. Dongsong series occur on Cheolweon lava plains derived from basaltic materials. Most soils distributed in Jeju Island, and derived from mainly pyroclastics are developed as Andisols. But Dongsong series distributed in Cheolweon lava plains which have a relatively dry climate and derived from basaltic materials are developed as Ultisols.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.229-240
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• 2009

The high temperature and water content in soil profile probably affect the physiological disorder especially on cool-season turfgrasses in warm and humid weather of Korean summer. The purpose of this research was to analyze the effect of soil temperature and water content on the growth and stress response of creeping bentgrass(Agrostis palustris Huds.) under a humid and warm temperature. USGA(United State of Golf Association) green profile in laboratory test, Daily temperature changes were tested under a dried sand, 70% water content of field capacity, and saturated condition at $34^{\circ}C$ of the USGA green in lab. In this test, the dried sand reached to $80^{\circ}C$, however, the surface temperature decrease of $10^{\circ}C$ on the saturated condition. In the thermal properties test in field, thermal conductivity, thermal diffusivity, and soil temperature were increased followed by irrigation practise. In the water-deficient condition, the highest soil temperature was reached temporally right after irrigation, however, the excessive soil water content higher than field water holding capacity showed the highest soil temperature after a while. This result indicated that a heat damage to root system was caused from the thermal conductivity of a high surface soil temperature. The excessive irrigation when a high turf surface temperature should occur a negative result on tufgrass growth, moreover, it would be fatal to root growth of creeping bentgrass, especially when associated with a poor draining system on USGA sand green. Overall, this study shows that high soil temperature with water-excessive condition negatively affects on cool-season grass during the summer season, suggesting that excessive irrigation, over 70% field capacity of soil condition, does not help to reduce soil temperature for summer season in Korea. In the study that cool-season grass were treated with different water content of soil, The soil had higher temperature and more water holding capacity when treatment rate of soil conditioner was increased. The best growth at the normal water condition and the worst state of growth at thee water-excessive condition were observed.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.10-13
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• 1995

The hypogeous ascomycete, Tuber aestivum subsp. uncinatum was isolated and identified for the first time in Korea from Quercus forest soil in Kyeryong-san National Park in August, 1992. The fungus is reported here with Korean name and English description. The specimen cited is deposited in herbarium of Department of Microbiology, Taejon University.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.486-486
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• 2022

미세플라스틱은 해양, 육상, 담수 및 대기환경에서 광범위하게 검출되고 있고 미세플라스틱에 대한 사람들의 우려가 커지고 있다. 담수환경에서의 미세플라스틱의 이동, 분포, 축척에 대한 연구는 해양환경에 비해 한정적으로 이루어지며, 하천은 종종 내륙에서 해양으로 미세플라스틱을 운반하는 경로로만 고려된다. 추후의 미세플라스틱의 저감정책 수립이나 이행에 있어서 미세플라스틱의 거동파악은 우선적으로 이루어져야한다. 따라서 오염의 생성에 영향을 미치는 유역의 작용을 가장 잘 표현하고, 단순히 전체의 상태를 설명하기보다는 인과관계를 밝히는 데에는 모델이 적합하다. 기후, 표면 유출, 토양이나 영양물질을 비롯한 오염물질의 부하 등을 잘 표현하고 수체 내부에서의 수질까지 동시에 시뮬레이션 가능한 기존의 잘 개발된 유역 모델의 주요 변수들은 미세플라스틱의 하천에서의 거동을 모의할 수 있다. 그 예로서 본 연구에서 HSPF의 유사(Sediment) 컴포넌트를 수정하여, 유역모델을 활용한 미세플라스틱 거동 모의 가능성을 입증하려고 한다.

• Journal of the Korean Geotechnical Society
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• v.31 no.2
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• pp.5-11
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• 2015

Slope stability is affected by duration of precipitation, probable rainfall intensity, unsaturated soil property, and soil strength. The recent analyses of slope stability tend to include unsaturated analysis based on infiltration properties of soil, while researches of unsaturated soil slope tend to include the analysis of deformation and stress distribution of soil over time. However, infiltration property of unsaturated soil slope depends not only on intensity or duration of precipitation, but also on relief and surface condition, which is not considered in status quo. This research uses hydrologic model parameters of soil in order to consider effects of inclination on filtration, and carries out analysis of unsaturated soil slope to confirm the effects according to slope inclination and surface condition. In conclusion, using slope stability analysis, the need to consider infiltration rate according to inclination and surface condition was confirmed even under the same precipitation conditions.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.184-190
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• 1997

Lesion enlargement of ginger rhizome rot was most rapid at 35~40 C, but delayed greatly as temperature decreased. Time needed for a killing a ginger plant, 22~25 cm long, was about 5 days at 35~40 C, but was 15 days at 15 C in a growth chamber test. Higher RH above 90%, higher soil moisture level above 80% of maximum soil moisture capacity, and deeper planting below 4cm enhanced the lesion development on ginger stems and rhizomes. Pythium myriotylum existed in field soil as forms of hyphal portion, hyphal swelling body, or oospore- or zoospore-like bodies, and served as the origin of its colonization. Inocula of P. myriotylum was randomly distributed in soil surface around ginger plants, but its density was decreased as increasing soil depth with the highest density at 0~10 cm soil depth. Population density of P. myriotylum did not vary significantly between the rhizoplane and the rhizosphere soil of a ginger plant, but differed greatly between the disessed and healthy plants with several to several hundreds times higher population in the diseased plants. A positive curvilinear relationship was found between P. myriotylum density and ginger rhizome rot severity.

• Journal of Biosystems Engineering
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• v.21 no.4
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• pp.414-421
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• 1996

한국과 일본의 경우 건표고를 외관의 품질상태 에 따라 12등급에서 16등급으로 구분하고 있다. 그리고 등급판정 작업은 임의로 추출한 샘플을 대상으로 전문 감정가에 의해 수작업으로 수행되고 있다. 건표고의 품질을 결정짓는 외관의 품질인자들은 갓과 내피에 고루 분포하고 있다. 본 논문에서는 컴퓨터 영상처리 시스템에 의거하여 개발한 건표고 자동 등급판정 및 선별 시작시스템의 구조와 기능 그리고 성능에 대하여 설명하였다. 개발한 시작시스템은 표고의 이송과 취급자동화를 위한 진동이송기, 반전장치, 컨베이어 이송장치와 두 세트의 컴퓨터 영상처리 시스템, 그리고 시스템 통괄제어를 위한 IBM PC AT호환 컴퓨터, 디지털 입출력 보드, 전공압실린더 구동제어를 위한 PLC등으로 구성하였다. 등급판정의 효율성 및 실시간 작업시스템을 고려하여 건표고의 등급판정은 두 세트의 컴퓨터 영상처리 시스템을 이용하여 이송되는 건표고의 갓 또는 내피 중 어디가 위를 향하는 지에 따라 두 단계에 걸쳐 독립적으로 판정을 수행하도록 하였다. 첫 번째 영상처리부에서는 갓표면 영상으로부터 4등급의 고품질 표고를 분류하며 두 번째 영상처리부에서는 내피표면 영상으로부터 중간 및 저품질 표고를 8개의 등급으로 분류한다. 실시간 영상정보처리를 목적으로 기존에 개발한 신경회로망을 이용한 등급판정 알고리즘을 시작시스템에 적용하였다. 개발한 시작기는 88% 이상의 등급판정 정확도를 보여 주었으며, 전공압시스템의 구동제약으로 인하여 표고 1개당 약0.7초의 선별시간이 소요되었다. 일조 선별라인의 경우 본 연구에서 제안한 시작기의 선별능력은 표고가 일차 처리부로 갓이 위로 올라와 있는 상태로 계속 공급된다면 시간당 대략 5,000여 개의 표고를 처리할 수 있을 것으로 기대된다.보강하여 가능하면 B-Pillar의 Middle이 Bending type collapse을 방지하여 Pelvis와 Door가 먼저 접촉하는 방법 등이 적용가능하다. 제작하기 이전에 설계된 부품에 대한 스프링 상수 및 내구특성을 체계적으로 규명하여 제품 시험의 횟수를 줄이고, 보다 정밀한 제품을 제작할 수 있도록 하기 위한 것이다.세포수는 초기 배반포기배에서 팽윤 배반포기배로 진행됨에 따라 두배에서 세배 정도 증가되었음을 알 수 있었다. 또한, differential labelling과 bisbenzimide기법에서 얻어진 각각의 총세포수를 비교하였을 때 총세포수는 발달의 진행 정도에 따라 증가되며 그와 동시에 동일한 군 간의 세포수도 거의 유사함을 알 수 있었다. 따라서, ICM과 TE를 differential labelling하는 기법은 수정란의 quality를 평가하는데 매우 유용한 기법으로서 착상전 embryo 발달을 연구하는데 효과적으로 이용될 수 있다는 것을 시사한다. 고도의 유의차를 나타낸 반면 비수구, 초생수로구 및 Bromegrass 목초구 간에는 아무런 유의차가 인정되지 않았다. 7. 농지보전 처리구인 배수구와 초생수로구는 비처리구에 비해 낮은 침두 유출량과 낮은 토양유실량을 나타내었다.구보다 14% 절감되는 것으로 나타났다.작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도성 물질로 증착시키지 않고, Silver Paint 에 시편을 접착하는 방법으로도 만족한 시험 결과를 얻을 수 있었다.째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰

• Conservation Science in Museum
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• v.30
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• pp.23-46
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• 2023

The Jija Chongtong Gun, owned by Seokdang Museum of Dong-A University, is a tubedstyle heavy weapon of the battlefield in the mid-Joseon Dynasty and is the second largest firearm after Cheonja Chongtong. The original surface color of the Jija Chongtong Gun was obscured by foreign substances and therefore it was judged that its condition requires the conservation treatment. For stable conservation treatment, gamma ray and X-ray non-destructive transmission surveys was conducted to determine the internal structure and conservation condition. And the component analysis on the material components and surface contaminants of Jija Chongtong Gun was conducted by utilizing the p-XRF component analysis, SEM-EDS component analysis, and XRD analysis. As a result of the gamma-ray and X-ray non-destructive transmission investigation, a large amount of air bubbles was observed inside Jija Chongtong Gun, and the part that appeared to be a chaplet by visual observation was not identified. As a result of gamma-ray and p-XRF component analysis, it was confirmed that Jija Chongtong Gun was bronze made of copper (Cu), tin (Sn), and lead (Pb) alloy. As a result of surface analysis of foreign substances using SEM-EDS, it was confirmed that the main components of white foreign substances were calcium (Ca), sulfur (S), and titanium (Ti). Titanium was presumed to be titanium dioxide (TiO₂), the main component of white correction fluid. The red foreign substance was confirmed to contain barium (Ba) as its main ingredient, and was presumed to be barium sulfate (BaSO₄), an extender pigment in paint. White and red contaminants, mainly composed of titanium and barium, are presumed to have been deposited on the surface in recent years. The yellow foreign substances were confirmed to be aluminum (Al) and silicon (Si), and were presumed to have originated from soil components. As a result of SEM-EDS and XRD component analysis, the white foreign substance was confirmed to be gypsum (CaS). Based on the results of component analysis, surface impurities were removed, stabilization treatment, and strengthening treatment were performed. During the conservation process, unknown inscriptions Woo (右), Byeong (兵), Sang (上), and Yi (二) were discovered through a portable microscope and precise 3D scanning. In addition, the carving method, depth, and width of the inscription were measured. Woo Byeong Sang is located above Happo Fortress in Changwon, and Yi can be identified as the second hill.