• 한국작물학회지
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• 제51권spc1호
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• pp.229-232
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• 2006

This study was conducted to select the most suitable dye bath soil of mat rush for good quality. Dry stem weight ranged from 102.5 to 107.0 g, dry stem ratio ranged from 34 to 36%, color of stem ranged from soft gray to heavy gray, degree of softness ranged from high to low and degree of floating ranged from extremely high to low. All the good quality components, such as dry stem weight, dry stem ratio, color of stem, degree of softness and degree of floating showed large variations. Hadong white ceramic soil, the superior dye bath soil of mat rush, showed relatively superior values for all the good quality components with 102.5 g in light dry stem weight, 34% in high dry stem ratio, good color of soft gray in color stem, high in degree of softness and extremely high id degree of floating. The results indicate that dye bath soils shows different adaptabilities to a particular dye bath and Hadong white ceramic soil seems to be the most suitable dye bath soil of mat rush for good quality.

• 한국토양비료학회지
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• 제48권4호
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• pp.285-294
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• 2015

Ordination has been recognized useful method to analyze the effects of multiple environmental factors on dozens of species in vegetation ecology because of summarizing community data by producing a low-dimensional graphics. Main objective of this study was the application of ordination method, especially principal components analysis (PCA), to analyze the soil characterization on paddy treated by different green manure crops and tillage methods. Treatments included the three tillage treatments and two green manure crops as the following; (i) moldrotary + rotary tillage without green manure crop (Con), with (ii) hairy vetch (ConHv), and (iii) hairy vetch + green barely (ConHvGb), (iv) rotary tillage without green manure crop (Rot), with (v) hairy vetch (RotHv), and (vi) hairy vetch + green barly (RotHvGb), and (vii) no-tillage (Notill). Vectorial distance result from PCA of soil properties including physical, chemical, and microbial properties showed the two main difference. Firstly, soil properties among plots without green manure were strongly affected by tillage strength [Vectorial distance: Con-Notil (5.88) > Rot-Notill (4.58)] at PC1 (35.0%) axis. But it was difficult to find the fixed trend among plots when green manure crop was added in plot. Nevertheless, two groups were separated by adding green manure crop at PC2 (29.2%) axis. These results show that PCA ordination methods could be used the research for change of soil characterization.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1989년도 봄 학술발표회 논문집
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• pp.22-27
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• 1989

This paper presents a study of soil-structure interaction problems using infinite elements. The infinite elements are formulated for homogeneous and layered soil media, based on approximate expressions for three components of propagating waves, namely Rayleigh, compressive and shear waves. The integration scheme which was proposed for problems with single wave component by Zienkiewicz is expanded to the multi-wave problem. Verifications are carried out on rigid circular footings which are placed on and embedded in elastic half space. Numerical analysis is performed for a containment structure of a nuclear power plant subjected seismic excitation.

• The Plant Pathology Journal
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• 제18권1호
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• pp.30-35
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• 2002

The hyphal growth and biocontrol efficacy of Trichodemo harzianum in soil may depend on its interactions with biotic components of the soil environment. The effect of soil microbial biomass on growth and biocontrol efficacy of T. hanianum isolate ThzIDl-M3 (green fluorescent protein transformant) was investigated using artificially prepared different levels of soil microbial biomass (153,328, or 517ug biomass carbon per g of dry soil; BC). The hyphal growth of T. harzanum was significantly inhibited in the soil with 328 or 517 $\mu$g BC compared with 153 ug BC. When ThzIDl-M3 was added to the soils as an alginate pellet formulation, the recoverable population of ThzIDl-M3 varied, but the highest population occurred in 517ug BC. Addition of alginate pellets of ThzIDl-M3 to the soils (10 per 50 g) resulted in increased indigenous microbial populations (total fungi, bacterial fluorescent Pseudomonas app., and actinomycetes). Furthermore, colonizing ability of ThzIDl-M3 on sclerotia of Sclerotinia sclerotiorum was significantly reduced in the soil with high revel of BC. These results suggest that increased soil microbial biomass contributes to increased interactions between introduced T. harzianum and soil microorganisms, consequently reducing the biocontrol efficacy of 1T. harzianum.

• 한국토양비료학회지
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• 제19권1호
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• pp.63-69
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• 1986

1. 각(各) 비종(肥種)의 시비수준별(施肥水準別) 잎중 양분함량(養分含量)은 질소(窒素)의 경우 증비(增肥)할수록 비옥지(肥沃地), 척박지(瘠薄地)에서 모두 증가(增加)하였으며, 인산(燐酸)은 증비(增肥)에 관계없이 비옥도간(肥沃度間), 시비수준간(施肥水準間)에 함량차이(含量差異)가 없었고, 가리(加里)의 경우에는 비옥지(肥沃地)가 척박지(瘠薄地)보다 동일시비수준(同一施肥水準)에서 칼륨함량(含量)이 다소 높았으나 척박지(瘠薄地)는 변화폭(變化幅)이 작았다. 2. 질소질비료(窒素質肥料)의 증비(增肥)는 특히 비옥(肥沃)한 경작지(耕作地)일수록 수확엽(收護葉)의 성숙(成熟)을 지연(遲延)시켰으며, 생육후기(生育後期)의 지나친 질소흡수(窒素吸收)는 니코틴함량(含量)을 증가(增加)시킴과 동시에 환원당함량(還元糖含量)을 저하(低下)시킴으로써 품질지수(品質指數)(환원당(還元糖)/니코틴비(比); Coulson계수(係數))도 낮아졌다. 3. 토양(土壤)의 비옥도(肥沃度)와 관계없이 잎담배중 질소함량(窒素含量)이 높아짐에 따라 니코틴함량(含量)도 비례(比例)하여 증가(增加)되었으나 니코틴함량(含量)의 점증(漸增)에 따라 환원당함량(還元糖含量)은 점감(漸減)하는 부(負)의 관계가 인정(認定)되었으며, 잎담배중 니코틴함량(含量)이나 환원당함량(還元糖含量)은 척박지(瘠薄地)에서보다 비옥지(肥沃地)에서 전반적으로 더 높았다. 4. 니코틴함량(含量)과 잎담배등급감정가격(等級鑑定價格)과는 부(負)의 상관(相關), 환원당함량(還元糖含量)과는 고도(高度)의 정상관(正相關)을 보임으로써 잎담배등급감정가격(等級鑑定價格)을 근거(根據)로 한 품질지수(品質指數)는 화학성분(化學成分)에 의한 품질측정치(品質測定値)와 매우 밀접한 관련이 있는것으로 인정(認定)되었다.

• 한국해안해양공학회지
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• 제17권1호
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• pp.41-46
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• 2005

항만구조물의 유체-구조물-지반 상호작용(FSSI)을 고려한 지진응답해석을 수행하였다. 우리나라 동남해안에 위치한 방파제 구조물을 대상으로 장주기 및 단주기파로 구분된 지진을 비롯하여 최근 우리나라에서 발생한 울진지진에 대한 지진응답특성에 대하여 고찰하였다. FSSI 효과를 고려하기 위하여 유체요소는 평면변형해석에 사용하는 4절점 사변형요소를 수정한 요소를 이용하여 모델링 하였다. 그리고 FSSI해석, 진도법, 부가질량법에 의한 지진응답특성을 비교하였다. 고유치해석을 통하여 방파제의 고유주기를 찾고, 기존의 지진 및 최근 우리나라에서 발생한 지진에 대한 지진응답특성 결과로부터 방파제 구조물이 장주기성분에 대한 영향을 더 많이 받는 것을 확인하였다.

• 한국유기농업학회지
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• 제8권3호
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• pp.91-98
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• 2000

몇가지 토양미생물제 처리가 근대의 수량과 식물체 및 토양의 화학성분, 그리고 미생물상에 미치는 영향을 조사하였다. 모든 미생물제 처리구에서 무처리에 비하여 수량이 증가하는 경향이 있었고, 특히 BLCS cattle dropping 처리구가 가장 높았다. 식물체의 화학성분에서는 모든 철구에서 Mg의 함량이 증가된 것을 제외하고 다른 성분들은 처리간에 차이가 없었고, 토양의 화학성분에서는 Tomi 처리구에서 K와 Mg의 함량이 높았으나, 다른 처리구에서는 차이가 없었다. 토양의 미생물상을 조사한 결과, 총세균수에서는 Tomi 처리구가 가장 높았고 Husk+Palma 처리구가 가장 높았고 Husk+Palma와 Tomi 처리구에서도 몹시 증가되었다. Actinomycetes와 fungi에서도 Tomi 처리구가 매우 증가하였으나, 다른 처리구간에는 차이가 없었고, pseudomonas에서도 각 처리간에 차이가 없었다.

• 한국토양비료학회지
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• 제50권5호
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• pp.369-382
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• 2017

Accurate and optimal water supply to cereal crop is critical in growing stalks and producing maximum yields. Recently, upland crops are cultivated in paddy field soils to reduce overproduced rice in Korea. In order to increase productivity of cereal crops in paddy fields which have poor percolation and drainage properties, it is necessary to fully understand crop response to excessive soil water condition and management of soil drainage system in paddy field. The objectives of this study were to investigate effects of excessive soil water to sesame growth and to quantify stress response using groundwater levels. Two cultivars of sesame were selected to investigate; Gunbak and Areum. These sesames were planted in paddy fields located in Miryang, Gyeongnam with different soil drainage levels and drainage systems. The experiment site was divided into two plots by drainage class; very poorly and somewhat poorly drained. Two different drainage systems were applied to alleviate excessive soil water in each plot: open ditch and pipe drainage system. Soil water contents and groundwater levels were measured every hour during growing season. Pipe drainage system was significantly effective to alleviate wet injury for sesame in paddy fields. Pipe drainage system decreased average soil moisture content and groundwater level during sesame cultivation. This resulted in greater yield and lignan contetns in sesame seeds than ones from open ditch system. Comparison between two cultivars, Gunbak had greater decrease in growth and yield by excessive soil water and high groundwater level than Areum. Seed components (lignan) showed decrease in seeds as soil water increased. When soil moisture content was greater than 40%, lignan content tended to decrease than ones from less soil moisture content. Based on these results, pipe drainage system would be more effective to reduce wet injury to sesame and increase lignan component in paddy field cultivation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.424-427
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• 2006

Soil contamination with petroleum oil around a military army was investigated. It showed that soils of a riverside highland, an entrance of the military army, and nearby roads were contaminated with total petroleum hydrocarbons (TPH) released from the military army to the depth of approximately 2 m. The measured concentrations were as high as 15,277 mg/kg. A wide range of soil in the riverside highland was contaminated by the movement of oil to the surface soil, which occurred with the vertical movement of groundwater table caused by the change of river water level and groundwater level. Spilled petroleum oil components were released into Wonju Stream by the increase of hydraulic conductivity and the groundwater flow.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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• pp.42-49
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• 1997

In this paper, the method for soil-structure interaction analyses in the time domain is proposed. The far field soil region which is the outside of the artificial boundary is modeled by using explicit frequency-dependent two dimensional infinite elements which can include multiple wave components propagating into the unbounded medium. Since the dynamic stiffness matrix of the far field soil region using the proposed infinite elements is obtained explicitly in terms of exciting frequencies and constants in the frequency domain, the matrix can be easily transformed into the displacement unit-impulse response matrix, which corresponds to a convolution integral of it in the time domain. To verify the proposed method for soil-structure interaction analyses in the time domain, the displacement responses due to an impulse load on the surface of a soil layer with the rigid bed rock are compared with those obtained by the method in the frequency domain and those by models with extend finite element meshes. Good agreements have been found between them.