• Title/Summary/Keyword: no-till

검색결과 367건 처리시간 0.026초

Effect of Tillage Management of Paddy Field on Runoff and Nutrient Losses during Non-Cropping Season

  • Yoon, Kwang-Sik;Choi, Jin-Kyu;Jun, Im-Sang
    • 한국농공학회지
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    • 제44권7호
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    • pp.53-63
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    • 2002
  • Runoff, sediments and nutrient losses were studied under different patterns of paddy field management: (1) fall and spring plowing (Plowing)i (2) fall plowing for half of plot and spring plowing (Semi-plowing); (3) no-till for fall and spring plowing (Un-plowing) during the non-cropping period in the southern Korea for two years. The runoff amount and initial abstract were significantly affected by plowing practices. Un-plowing plot showed the highest runoff amount among treatments. The concentrations of sediment from Plowing plot were much higher than those from Un-plowing plot, especially after (all plowing. Sediment losses from Plowing plot were 25% more than those from Un-plowing plot. There was significant difference in nutrient losses via runoff water and sediment according to plowing practice. Two-year average of losses of N from paddy field during non-cropping period were 9.42 kg ha$\^$-1/, 8.17kg ha$\^$-1/, and 7.76 kg ha$\^$-l/ for Un-plowing, Semi-plowing, and Plowing plot, respectively, while losses of P were 0.64 kg ha$\^$-1/, 0.58 kg ha$\^$-1/, and 0.58 kg ha$\^$-1/ for each tillage system. Losses of total-N, ammonia-N, nitrate-N, Total-P from Un-plowing plot was larger than those from Plowing and Semi-plowing plots during study period.

기성금관수복 유구치의 변연 적합도에 관한 연구 (A STUDY ON MARGINAL ADAPTATION OF READY-MADE STAINLESS STEEL CROWN TO THE PRIMARY MOLAR)

  • 이선경;이광수;김종철
    • 대한소아치과학회지
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    • 제23권2호
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    • pp.389-400
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    • 1996
  • In Class II amalgam restoration in deciduous molar, failure rate and incidence of recurrent caries are high as children become older. In order to preserve deciduous molars till the physiologic exfoliation time, stainless steel crown is a choice of the treatment. As a result of a careless treatment, such as overhanging margin, poor marginal adaptation, poor proximal contour and inadequate mesiodistal width give rise to interfering eruption of the adjacent teeth, recurrent caries and chronic gingival irritation and insufficient arch length respectively. In this study, 252 s.s. crowned teeth extracted due to physiologic exfoliation or periapical lesion. The purpose of this study is to analyze the marginal adaptation of stainless steel crown to the deciduous molar in order to obtain better clinical result. The results were as follows : 1. Between the length of s.s. crown and the marginal gap of crown, positive correlations were shown. 2. Largest amount of marginal gap was shown at buccal side in upper deciduous molars and lower first deciduous molar, lingual side in lower second deciduous molar. But no significant diffrence were found statistically compared to second most largest one. 3. Incidence of exposed restoration and recurrent caries were higher in proximal surface than buccal/lingual surface. And extension of restoration below the margin of s.s. crown gives rise to higher rate of recurrent caries. 4. Defect of contour was found in 34%, frequently found in lower 1st deciduous molar and upper 1st deciduous molar. 5. Marginal polishing defects were found in 23%. 6. Ledge was formed in 10% especially in lower 1st deciduous molar and lower 2nd deciduous molar. 7. 16% of the teeth had wear facet due to traumatic occlusion, 7% of them had occlusal perforation.

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Development of SSR markers for genetic mapping of Korean ginseng and authentication of Korean ginseng cultivars

  • Kim, Nam-Hoon;Choi, Hong-Il;Jung, Ju-Yeon;Choi, Beom-Soon;Ahn, In-Ok;Lee, Joon-Soo;Yang, Tae-Jin
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2010년도 정기총회 및 추계학술발표회
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    • pp.11-11
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    • 2010
  • The Korean ginseng, Panax ginseng C. A. Meyer is a popular medicinal herb in Araliaceae. Genetic map in crops provides valuable information for breeding, genetic and genomic researches. However, little information is available for construction of genetic map in ginseng. Up to now, we have produced large amounts of expressed sequence tags (ESTs) from four ginseng cultivars (37Mb, 49Mb, 39Mb, 47Mb from Gopoong, Gumpoong, Chunpoong and Yunpoong respectively using pyrosequencing technique and 5Mb from normalized full-length cDNA library of Chunpoong) to obtain comprehensive information of gene expression, and constructed EST database including ESTs from public database. Till now, we designed 261 SSR primer sets using EST sequences and identified 106 intergenic polymorphic markers. And 44 of the 106 showed polymorphisms among panax ginseng cultivars. Among 44 markers, 27 SSR polymorphic markers were inspected to 51 $F_2$ population from Yunpoong x Chunpoong, which showed good at the fitness of Mendellian segregation ratio 1:2:1. To enrich the number of markers, and thus construct high resolution genetic map which can be used as frame map for further genome sequencing. we are planning to develop large scale EST-derived SNP markers which are available in the F2 population. This study provides genetic information as well as foundation for ginseng researches such as genetics, genomics, breeding, and the final goal for whole genome sequencing. This study was supported by Technology Development Program for Agriculture and Forestry, Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea (Grant No. 609001-051SB210).

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Integrated Korean Flora Database: A Versatile Web-based Database for Dissecting Flora Investigations

  • Yeon, Jihun;Kim, Yongsung;Kim, Hyejeong;Kim, Juhyun;Park, Jongsun
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 춘계학술발표회
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    • pp.16-16
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    • 2018
  • Flora investigations have been conducted by many researchers for a long time in Korea. Even though large amount of investigation data has been accumulated, there is no accurate statistics or database because most of data were published in a printed form. We developed a web-based database of flora investigation, named as the Integrated Korean Flora Database (http://www.floradb.net/) to understand distribution patterns and habitats of plants in Korea. Till now, 480 published paper, 356 thesis, 76 reports and books, and 8 unpublished papers written in between 1962 and 2017 were collected and their species lists from 280 papers were parsed into the database. From 124,105 records, 3,100 species belonging to 206 families and 965 genera were identified via comparing with two major Korean plant species lists. 55 endangered species, 159 endemic species, and 367 rare species were identified. The most frequently surveyed species were Commelina communis in herbaceous and Rosa multiflora in woody plants. Microclimate data provided by Korea Meteorological Administration were also integrated and analyzed to assign cold hardness zones for each species. By comparing minimum temperature (<2%) acquired from automated weather stations (AWS) near by plant species, 6a to 10b zones (7b is the most frequent zone) were identified. Integrated Korean Flora Database will be a fundamental platform of korea flora investigation as well as a new standard for classifying distribution of plants based on accurate microclimate data. Moreover, it can also provide evidences of investigated plant species, such as specimen and/or pictures with connecting to the InfoBoss Cyber Herbarium (http://herbarium.infoboss. co.kr/) and Biodiversity Observation Datbase (BODB; http://www.biodiversitydb.org/).

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척수 손상 쥐에 실시한 특정 과제 운동이 운동 행동에 미치는 영향 (Effects of Specific Exercises on Motor Function Recovery In Rats With Experimental Spinal Cord Injury)

  • 전경희
    • 한국전문물리치료학회지
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    • 제18권1호
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    • pp.93-103
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    • 2011
  • This study was implemented to verify the feasibility of motor function recovery and the appropriate period for therapy. The research began with spinal laminectomy of 40 white rats of Sprague-Dawley breed and induced them spinal crush injury. Following results were obtained by using the modified Tarlov test (MTT), Basso, Beattle, Bresnahan locomotor rating scale (EBB scale) and modified inclined plate test (MIPT). First, the measurement using the MTT confirm that the most severe aggravation and degeneration of functions are observed two days after induced injury, and no sign of neuromotor function recovery. Second, better scores were achieved by open-ground movement group on BBB locomotor rating scale test, and weight-bearing on inclined plate group show better performance on MIPT. Third, both BBB and MIPT scale manifested the peak of motor function recovery during 16th day after the injury and turn into gradual recovery gradient during 16th to 24th. Fourth, the control group showed functional recovery, however, the level of recovery was less significant when compared with group open-ground movement group and weight-bearing on inclined plate group. Hence, it was clearly manifested that the lumbar region of the spinal cord had shown the best performance when its functions were measured after the execution of specific physical training; therefore it indicated the possibility of learning specific task even in damaged lumbar regions. Thus it is expected to come out with better and more effective functional recovery if concentrated physical therapy was applied starting 4 days after the injury till 16 days, which is the period of the most active recovery.

공기-분말 연마와 구연산의 적용시간에 따른 임프란트 표면 거칠기의 변화에 관한 주사탐침현미경적 연구 (The SPM Study on the Change of Titanium Surface Roughness following Airpowder Abrasive and Application Time of Citric Acid)

  • 박민서;정진형;임성빈
    • Journal of Periodontal and Implant Science
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    • 제30권4호
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    • pp.821-836
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    • 2000
  • The Peri-implantitis causes inflammation of periodontal tissue and bone loss. It contaminates surface of implants. Therefore, guided bone regeneration has been used for the treatment of this disease. For the reosseointegration of the exposed surface, various mechanical and chemical methods have been used for cleaning and detoxication of implant surface. Among these methods, air-powder abrasive and oversaturated citrate are known to be most effective. However, these treatments may deform implant surface. In this research, changes of surface roughness they were examined. 10 experimental machined titanium cylinder models were fabricated to be used for control groups. Each of them was air powder abraded for 1 minute and they were named group 1. And then, group 1 were burnished with cotton pellets soaked with citrate for 30 seconds(Group 2), 1 minute(Group 3), 3 minutes(Group 4), and 5 minutes(Group 5) burnishing were applied for grouping respectively. Each group were examined with SPM, and their surface roughness were measured and analyzed. 1. Surface roughness of titanium decreased when it was air-powder abraded for 1 minute. It was statistically significant. 2. When Air-powder abraded titanium were treated with citrate for 3 minutes, Their surface roughness was the lowest. Titanium treated for 1 minute was the second lowest and 30 seconds was the third and titanium burnished for 5 minutes was the highest. 3. Surface roughness of titanium which was treated with citrate was decreased till 3 minutes, which was statistically significant. There was no statistical significance from 30 seconds to 1 minute and from 1 minute to 3 minutes, and there was statistical significance from 30 seconds to 3 minutes. 4. Oxide layer was formed when titanium is exposed to air, and it was removed when air-powder abraded. It was made when treated with citrate. It is thought that citrate treatment is necessary after the air-powder abrasion, and 1 minute is clinically and qualitatively adequate for burnishing time of citrate.

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Evaluation of Toxicity and Gene Expression Changes Triggered by Quantum Dots

  • Dua, Pooja;Jeong, So-Hee;Lee, Shi-Eun;Hong, Sun-Woo;Kim, So-Youn;Lee, Dong-Ki
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1555-1560
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    • 2010
  • Quantum dots (QDs) are extensively employed for biomedical research as a fluorescence reporter and their use for various labeling applications will continue to increase as they are preferred over conventional labeling methods for various reasons. However, concerns have been raised over the toxicity of these particles in the biological system. Till date no thorough investigation has been carried out to identify the molecular signatures of QD mediated toxicity. In this study we evaluated the toxicity of CdSe, $Cd_{1-x}Zn_xS$/ZnS and CdSe/ZnS quantum dots having different spectral properties (red, blue, green) using human embryonic kidney fibroblast cells (HEK293). Cell viability assay for both short and long duration exposure show concentration material dependent toxicity, in the order of CdSe > $Cd_{1-x}Zn_xS$/ZnS > CdSe/ZnS. Genome wide changes in the expression of genes upon QD exposure was also analyzed by wholegenome microarray. All the three QDs show increase in the expression of genes related to apoptosis, inflammation and response towards stress and wounding. Further comparison of coated versus uncoated CdSe QD-mediated cell death and molecular changes suggests that ZnS coating could reduce QD mediated cytotoxicity to some extent only.

한국 남성 비즈니스 캐주얼의 경향 및 디자인 특성 (An Analysis of Trend and Design Characteristics on the Korea Men's Business Casual)

  • 김초롱;염혜정
    • 복식
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    • 제60권10호
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    • pp.16-27
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    • 2010
  • Business Casual has been launched because of 'Friday Wear' in the 1990s and in Korea, the business casual has been settled under the influence of the five-day work week. The idea of business casual is that 'Business' and 'Casual wear' are combined. It is the attire that people should wear the jacket for formality and people can wear both on or off duty. As a result of the analysis, based on this, of the characteristics of men's business casual appeared in Seoul collections from 2009 till now, they can be classified in 'Classic & Traditional business casual', 'Modern business casual', 'Natural business casual', 'Feminine business casual' and 'Sporty business casual'. As a result of the analysis of the design characteristics of the Korean men's business casual and the trend, based on the content of the analysis of Seoul Collection, 'Classical Classic & the Traditional', 'Modern of the Contemporary design', 'Natural of the Natural design' and 'the Sporty business casual of the Separate Coordination' including jeans, have presented themselves. Also, as a result of the analysis of Korean business men's business casual according to the classification of the design characteristics in Chapter III, 'Classic & Traditional business casual' account for the majority and then 'Sporty', 'Modern' and 'Natural business casual' account for the rest in order. 'Feminine business casual' hasn't presented itself. As a result of the comparative analysis of the design characteristics in Chapter III & IV, Korean business men's business casual has been concentrated on 'Classical & Traditional' and the design characteristics have not appeared in variety. There has been no such audacious attempt, and items, the characteristics of coordination, colors and materials are not in variety compared to the collection. Meanwhile, as a result of the subsistent characteristics of Koran business men's business casual, the characteristics of business men's business casual can be said to represent themselves in "Separate Coordination with the previous items of formal suits".

위험도 평가기준을 적용한 저수지 최적운영방안 연구(I) (대청댐을 중심으로) (A Study of Optimal Operation Policy using Risk Evaluation Criteria(I) (for the Daechung Multi-purpose Reservoir))

  • 박명기;김재한;정관수
    • 한국수자원학회논문집
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    • 제35권1호
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    • pp.37-49
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    • 2002
  • 이수목적 수량관리를 위한 보장수량과 수력발전 등을 고려한 최적화 기법은 이상가뭄 또는 특이 수문년을 포함하는 경우에는 적용에 한계가 있다. 이러한 관점에서 Hashimoto 등(1982)에 의해 제안된 물부족에 관련된 3가지 평가기준을 혼합정수계획법을 통해 최적화모형에 반영하기 위한 Moy 등(1986)과 Srinivasan 등(1999)에 의해 제시된 바 있다. 그러나 이들 연구는 용수공급용 단일 저수지에 대해 한정되어 발전을 포함하는 다목적댐에 적용할 수 있는 정식화 연구는 부진한 실정이다. 본 연구에서는 다목적댐의 용수공급 및 수력발전 최적화 문제에 위험도 평가기준을 도입하여 운영평가를 위한 정식화 형태를 개선하였으며, 개선된 모형을 금강수계 대청다목적댐에 적용하여 그 실효성을 평가하였다.

초고층 주상복합 건물의 개발사업 단계에 따른 주변지역 아파트가격의 변화에 관한 연구 (A Study on the Changes of the Apartment price in Accordance with Project process of Super high-rise mixed use buildings)

  • 김상환;최원철;김주형;김재준
    • KIEAE Journal
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    • 제10권5호
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    • pp.159-164
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    • 2010
  • High-rising buildings are a sort of solution to recent cities. Till now real estate development was concentrated in new development on vacant lots, and it resulted urban sprawl. Generally large cities are confronted with the exodus of industry and population from city. High-rising buildings solve many problems associated with this problem. The purpose of this research is to identify the effect of super high-rise mixed use building project process on apartment price. For this study, the hypothesis is that price of apartments is influenced by project process of super high-rise mixed use building. The study concerned 4 variations of project process that is building permits stage, sale stage, construction starting stage and stage of moving into building. The target projects of buildings are selected by number of floor(over 40 floors) and construction time. And 48 apartment complex are selected around super high-rise mixed use building. This study uses hedonic price function to analysis effect of project process of super high-rise mixed use building. A price of apartments is defined as a dependent variable. Characteristics of residence, complex, district and super high-rise building are defined as independent variables. The results are as follows; first, there is no error in price model of this study. Second, it is found that apartment price was influenced negatively by building permit stage and sale stage of super high-rise mixed use building. But that was influenced positively by construction starting stage and stage of moving into building of that. Third, as the project process of super high-rise mixed use building was proceeded, price of apartments was increased.