• 한국약용작물학회지
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• 제17권5호
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• pp.346-351
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• 2009

To study the optimal cultivation for paddy soil, growth characteristics and ginsenoside content was investigated by both of poor drainage class (PDC) and imperfect drainage class (IDC) in three-year-old ginseng of varieties, Cheonpoong (CP), Yeonpoong (YP), Hwangsookjong (HS), and Jakyeongjong (JK). Root yield of IDC was higher than that of PDC by 3.6 times because stem length, leaf area, and chlorophyll contents were increased, while discolored leaf ratio was decreased. Root yield of HS in PDC was highest among four varieties because chlorophyll contents, leaf area, and survived plant ratio were relatively high. Root yield of CP in IDC was highest among four varieties because of high leaf area and survived plant ratio, and low discolored leaf ratio. Ratio of rusty-colored root showed significant difference by varieties, which was the highest in HS and the lowest in CP among four varieties irrespective of drainage classes. Total ginsenoside contents showed significant difference by drainage classes, which were high in IDC of good growth and low in PDC of poor growth. Total ginsenoside contents were high in JK and CP, while low in HS and YP both of drainage classes.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.153-153
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• 2010

Recently, to develop GaN-based light-emitting diodes (LEDs) with better performances, various approaches have been suggested by many research groups. In particular, using the patterned sapphire substrate technique has shown the improvement in both internal quantum efficiency and light extraction properties of GaN-based LEDs. In this paper, we discuss the influences of the direction of the hexagonal-structure arrays of lens-shaped patterns (HSAPs) formed on sapphire substrates on the crystal, optical, and electrical properties of InGaN/GaN multi-quantum-well (MQW) LEDs. The basic direction of the HSAPs is normal (HSAPN) with respect to the primary flat zone of a c-plane sapphire substrate. Another HSAP tilted by 30o (HSAP30) from the HSAPN structure was used to investigate the effects of the pattern direction. The full width at half maximums (FWHMs) of the double-crystal x-ray diffraction (DCXRD) spectrum for the (0002) and (1-102) planes of the HSAPN are 320.4 and 381.6 arcsecs., respectively, which are relatively narrower compared to those of the HSP30. The photoluminescence intensity for the HSAPN structure was ~1.2 times stronger than that for the HSAP30. From the electroluminescence (EL) measurements, the intensity for both structures are almost similar. In addition, the effects of the area of the individual lens pattern consisting of the hexagonal-structure arrays are discussed using the concept of the planar area fraction (PAF) defined as the following equation; PAF = [1-(patterns area/total unit areas)] For the relatively small PAF region up to 0.494, the influences of the HSAP direction on the LED characteristics were significant. However, the direction effects of the HSAP became small with increasing the PAF.

• 수산해양기술연구
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• 제48권2호
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• pp.128-136
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• 2012

Hybrid surveys using hydroacoustic and fish sampling gears such as trammel net, trap were conducted to investigate total biomass, distribution and dominant fish species of the demersal fishes in the marine ranching area (MRA) of Jeju. Four surveys were carried out in June, August, October and November using 38kHz quantitative echo sounder. Catch data using trammel net and trap were used to calculate biomass and to examine dominant fish species. Fish schools were mainly detected in the waters of 20 meters below and around Chagwido waters. By the result of fishing experiments, fish species living in MRA of Jeju were about 40 species, dominant fish species of a detectable fish such as Family Sparidae and Family Monacanthidae etc. were identified 59.4~68.8% of total biomass. Based on the hydroacoustic data, fish length-weight function and target strength information, mean density of the demersal fish estimated were as follows; 0.88g/$m^2$ on June, 1.12g/$m^2$ on August, 1.35g/$m^2$ on October and 1.18g/$m^2$ on November. An estimated average biomass in MRA of Jeju was founded 20.5 tons in 2007, 20.6 tons in 2008, 23.0 tons in 2009, 25.9 tons in 2010. The results showed that biomass of MRA is getting increased slowly. Therefore the hybrid survey method using hydroacoustic and fish sampling gears is assured an effective biomass survey in the waters of mixed species.

• Journal of Korean Dental Science
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• 제4권2호
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• pp.46-51
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• 2011

Purpose: For aesthetic reasons, composite resin brackets are widely used. However, related studies are rare. This pilot study sought to compare the stress distributions in two commercially available composite resin brackets with metal slot. Materials and Methods: Two commercially available resin brackets -- full-metal slot resin bracket (fSRB) and partial-metal slot resin bracket (pSRB) with straight wire appliance dimension of $0.022{\times}0.028$ in -- were selected. In each bracket, 3-dimensional finite element models were constructed, and stress level was evaluated using finite element analysis. By loading the tipping force and torsion moment, which are similar to those applied by the stainless steel rectangular wire ($0.019{\times}0.025$ -in), stress distributions were calculated, and von Mises stress values were obtained. Results: In pSRB and fSRB, the stress value of the torque moment was much higher than that of the tipping force. The pSRB showed higher stress value than fSRB in both tipping force and torque moment because of the difference in size and configuration of the metal frame inserted into the slot. More stress was also found to be concentrated on the slot area than the wing area in fSRB. Conclusion: The slot form of fSRB was found to be more resistant to the stress of tipping and torque than the slot form of pSRB. In addition, the slot areas -- rather than the wing areas -- of the bracket showed breakage susceptibility. Therefore, resistance to the torque moment on the slot area should be considered in bracket design.

• 한국멀티미디어학회논문지
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• 제20권3호
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• pp.456-464
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• 2017

The epigraphy is a text on metal or a text on stone. The value of epigraphy can be used to identify historical facts of the past. It is a good record to understand the past life and culture. But it is difficult to decode the character of the epigraphy which has been exposed to the outdoor for a long time. In this study, the proposed techniques are consisted of 3 parts: (1)The surface division into information area, non- information area, and undifferentiated area. And then, (2) The selection of points in the non-information area and finding a reference plane with the minimum error. (3) Flattening the points perpendicular to the reference plane and decoding characters on information area. This research contributes to narrow the scope of a particular letter and to read the controversial letters on the Pohang Jungsoengri Silla Stone Monument(Korea's national treasure number 318).

• Mycobiology
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• 제44권4호
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• pp.277-282
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• 2016

In this study, we collected rhizosphere soils and root samples from a post-mining area and a natural forest area in Jecheon, Korea. We extracted spores of arbuscular mycorrhizal fungi (AMF) from rhizospheres, and then examined the sequences of 18S rDNA genes of the AMF from the collected roots of plants. We compared the AMF communities in the post-mining area and the natural forest area by sequence analysis of the AMF spores from soils and of the AMF clones from roots. Consequently, we confirmed that the structure of AMF communities varied between the post-mining area and the natural forest area and showed significant relationship with heavy metal contents in soils. These results suggest that heavy metal contamination by mining activity significantly affects the AMF community structure.

• Ecology and Resilient Infrastructure
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• 제3권1호
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• pp.46-53
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• 2016

본 연구는 수원시 도심에 위치한 도시공원인 효원공원을 대상으로 여름철 대기온도 저감효과를 확인하고, 공원을 구성하는 서로 다른 피복유형별 특성을 파악하기 위하여 열 환경을 실측하고 분석하였다. 도시공원의 여름철 대기온도저감효과는 도심주거지 (매탄동) 대비 평균 4.4-4.5%로 통계적으로 유의하였고 (p< 0.001), 수원시의 외곽주거지 (상광교동) 보다는 약 0.8% 낮은 수준이었다. 도시공원 내 피복유형 (보도 블럭, 잔디 식재지, 소나무-잔디 식재지, 수목 차광지 및 혼합림 조경지)에 따른 열환경은 자연소재의 유형일수록 일평균기온, 일최고기온, 여름일수가 낮은 경향을 보였다. 그러나, 일최저기온 및 열대야일수는 피복유형에 따른 상관관계가 뚜렷하게 나타나지 않았다. 오후시간대 (13:00-15:00)에 혼합림 조경지, 수목 차광지, 소나무-잔디 식재지의 불쾌지수 (DI), 습구흑구온도 (WBGT) 및 열지수 (HI)의 평균값이 보도 블록과 잔디 식재지보다 낮아서 자연소재의 피복 유형의 열쾌적성이 양호한 것으로 나타났다. 그러나 각 지수에 대한 등급은 모든 피복 유형에서 '가장 높음' 또는 '주의' 단계로 동일하였다. 한편 오전 (06:00-08:00)에는 토지 피복유형별 열쾌적성에 차이가 없었다. 결론적으로 도시에서 열 환경을 개선하기 위하여는 초지, 숲 및 개방 지역의 토지 피복 유형을 증가하여야 한다.

• 농약과학회지
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• 제19권2호
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• pp.113-118
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• 2015

고추 흰가루병이 수량에 미치는 영향을 조사하여 경제적 방제수준을 설정하고자 시험을 수행하였다. 고추 흰가루병의 발병 정도에 따른 수량의 변화에 대한 분석은 병발생을 10단계 수준으로 구분하여 시험을 실시하였다. 흰가루병 발생수준과 과장, 과경, 과중은 부의 상관관계를 형성하였으며, 발생이 증가함에 따라 수량이 감소하여 유의한 부의 상관관계가 형성되었다. 시설고추 흰가루병 발생 정도와 수량과의 회귀식은 천하통일과 부촌품종이 각각 Y = -2.136X+327.9 $R^2=0.76$, Y = -3.44X+291.1 $R^2=0.73$ 성립되었으며, 시설고추 흰가루병 발생 정도와 수량 손실량과의 회귀식은 천하통일과 부촌품종이 각각 Y = 2.14X+15.45 $R^2=0.76$ $r=0.87^{**}$ Y = 3.44X+11.21 $R^2=0.73$ $r=0.85^{**}$ 성립되었다. 따라서 시설 고추 수량에 영향을 주지 않는 수준의 흰가루병 방제 적기는 발생 병반면적률이 3.2~7.3% 이하 이었으며. 고추 흰가루병 경제적 방제수준은 시설 고추 흰가루병 발생 정도가 3.8~6.2% 이하 일 때 방제를 시작하면 방제횟수를 절감 하면서 효율적인 방제를 할 수 있다.

• 한국환경과학회지
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• 제21권12호
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• pp.1477-1485
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• 2012

This study examined urbanization effects and the causes of urbanization, urban population growth, increase of the city scale, land cover change, and human cultures and economic activities, using the daily minimum temperatures of the past 50 years (1961-2010) with the subject of Busan and analyzed correlations between urbanization effects and the causes of urbanization. Thereby, this paper drew a conclusion as below: 1) Due to the urbanization effects, the average annual daily minimum temperature increased as about $1.2^{\circ}C$; however, except for the factor of urbanization, the increase was shown as about $0.2^{\circ}C$. The occupancy of urbanization effects in the total temperature increase was quite high as about 83%. 2) Just like other cities experiencing urbanization, Busan, too, sees population growth and the expansion of city area as well as increased urbanization effects. First of all, correlation between population growth and urbanization effect was high as 0.96 before 1985 while it was lowered as 0.19 after 1985. Also, correlation between the increase of city area and urbanization effect was high as 0.64 and 0.79 before and after 1985. 3) Regarding the correlation between long-term land use change and urbanization effect, urbanization effect was affected greatly by the increase of city area (0.97) and reduction of green area (0.92). 4) Concerning human activities possible to affect the climatic factors of a city, this paper found the following factors: road length, car increase, power use, and the consumer price index, etc. And regarding the correlation between the three factors and urbanization effect, the correlation was higher in the consumer price index (0.97), the number of registered cars (0.89), power use (0.75), and road length (0.58) in order.

• 한국어류학회지
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• 제24권2호
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• pp.84-93
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• 2012

본 연구에서는 2007년 여름, 2009년 겨울, 2010년 봄, 여름과 가을까지 총 5회의 조사를 통하여 36과 92종의 어류가 출현하였다. 종다양성 지수는 1.893~2.962, 균등도 0.050~0.231로 나타났다. 낙동강 하구 주변 해역에서 조사한 연구에서 출현종 수는 1998년 봄에 72종으로 가장 많았으며, 2002년 겨울에 10종으로 가장 적었다. 단위면적당 개체수에 대한 상위 10종에 대한 우점 비율은 전체 어획개체수의 70% 이상을 차지하는 것으로 나타났다. 종다양성 지수는 1.234~2.962의 범위를 나타냈으며, 균등도는 0.047~0.324의 범위를 나타냈다. 주요 우점종은 성대, 청보리멸, 반딧불 게르치, 황아귀, 열동가리돔, 홍어, 물가자미, 문치가자미, 달고기, 보구치로 어획개체수와 어획량 모두 높았다. 이전 연구를 포함한 총 23회의 조사에서 상위 10종의 우점어류의 대한 유사도 분석에서는 연별 계절별 어종의 변화가 큰 것으로 나타났으며, 1987~1988년과 1998년, 2001~2002년, 그리고 2007~2008년과 2009~2010년의 조사로 세 그룹으로 구분되었다. 체장조성의 변화는 현 연구에서는 이전연구보다 평균체장이 크고 체장범위도 어획최소체장이 커지고 범위도 더 넓었다. 우점종의 서식밀도 변화를 살펴보면, 현 연구의 우점종은 이전 연구에 비하여 어획개체수가 증가하였으며, 어획량도 많아졌다. 특히, 황아귀, 홍어, 물가자미, 달고기는 2008년 이후 조사에서 이전연구보다 개체수와 어획량이 월등하게 높아졌다. 이전 연구의 주요 우점종인 꼼치, 실양태 그리고 주둥치는 2002년 이전까지의 연구에서 어획개체수가 많았으며, 2008년 이후 연구에서 어획 개체수가 급격히 줄었다.