• 한국잡초학회지
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• 제16권2호
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• pp.108-113
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• 1996

건답직파답(乾畓直播畓)에서 중요 우점초종(優點草種)인 피를 전년도에 방제시(防除時) 다음해 잡초발생(雜草發生) 생태변화(生態變化)와 직파답(直播畓)에 발생이 증가(增加)되고 있는 사마귀풀의 효과적(效果的)인 방제연구(防除硏究)를 위해 수행(遂行)한 시험결과(試驗結果)를 요약(要約)하면 다음과 같다. 1. 전년도 출수전(出穗前) 피를 완전히 방제(防除)한 구는 무방제구에 비하여 총(總) 잡초발생량(雜草發生量)은 파종후(播種後) 30일에 47.7%, 파종후(播種後) 60일에 7.8%가 감소(減少)하였다. 초종별(草種別)로는 파종후(播種後) 60일에 피는 46.9% 감소(減少)하였으나 사마귀풀, 여뀌는 각각 231%, 11.8% 증가(增加)하였다. 2. 군락내(群落內) 발생초종의 다양성(多樣性) 정도를 나타내는 다양성(多樣性) 계수(係數)는 방제구에서 낮았으며 방제구에서는 피의 우점도(優點度)가 떨어진 반면 특히 사마귀풀의 우점도(優點度)가 높아졌다. 3. 사마귀풀은 대체로 파종후(播種後) 40일 전후부터 벼 생육(生育)에 영향을 주었고, 사마귀풀 $m^2$당 300본 및 700본 구는 무발생구(손제초구)대비 수수가 61-72% 적고 등숙비율(登熟比率)이 5-15% 떨어져 쌀 수량(收量)이 74-93% 감수(減收)되었다. 4. 수량성과 다른 잡초방제효과(雜草防除效果)를 고려한 사마귀풀의 효과적(效果的)인 방제방법(防除方法)은 Butachlor(파종후(播種後) 5일)와 Propanil/Molinate(파종후(播種後) 25일)를 체계처리(體系處理)와 파종후(播種後) 20일 Lgc 40863 + Pendimethalin의 일발처리(一發處理) 하는 것이 효과적(效果的)이라는 결과(結果)를 얻었다.

• 대한기계학회논문집B
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• 제23권10호
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• pp.1265-1273
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• 1999

PIV(Particle Image Velocimetry) velocity field measurements inside the snout of a1/10 scale model of the Zn plating process were carried out at the strip speed $V_s=1.5m/s$. Aluminum powder particles ($1{\mu}m$) and atomized olive oil ($3{\mu}m$) were used as seeding particles to simulate the molten Zinc flow and deoxidization gas flow, respectively. A pulsed Nd:Yag laser and a $2K{\times}2K$ high-resolution CCD camera were synchronized for the PIV velocity field measurement. From flow visualization study, it is found that the liquid flow in the Zn pot is dominantly governed by the uprising flow caused by the rotating sink roll, with its effect on the steel strip inside the snout largely diminished by installing of the snout. The deoxidization gas flow in front of the strip inside the snout can be characterized by a large-scale vortex rotating clockwise direction formed by the moving strip. In the rear side of the strip, a counter-clockwise vortex is formed and some of the flow entrained by the moving strip impinges on the free surface of molten zinc. The liquid flow in front of the strip is governed by the flow entering the snout, caused by the spinning sink roll. Just below the free surface a counter-clockwise vortex is formed near the snout wall. The moving strip affects dominantly the flow behind the strip inside the snout, and large amount of the liquid flow follows the moving strip toward the sink roll. The thickness of the flow following the strip is very thin in the front side due to the uprising flow, however thick boundary layer is formed in the rear side of the strip. Its thickness is increased as moving downstream toward the sink roll. Inside the snout, the deoxidization gas flow above the free surface is much faster than the liquid flow in the zinc pot. Due to the larger influx of the flow following the moving strip in the rear side of the strip, higher percentage of imperfection can be anticipated on the rear surface of the strip.

• 농업과학연구
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• 제11권1호
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• pp.68-76
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• 1984

수도상자육묘(水稻箱子育苗)에 있어서 이상적(理想的)인 치묘(稚苗)와 중묘(中苗) 그리고 성묘(成苗)의 육성(育成)에 알맞은 재배조건(栽培條件)을 구명(究明)하고져 파종밀도(播種密度)와 비료용량(肥料用量), 육묘(育苗)의 시기(時期)와 일수(日數)의 영향(影響)을 분석(分析)한바, 파종량(播種量)은 적을수록, 시비량(施肥量)은 많을수록, 만파(晩播)일수록, 육묘기간(育苗期間)이 연장(延長)될수록 초장(草長), 엽수(葉數) 및 건물중(乾物重)은 증대(增大)하였는데 그 영향(影響)은 파종기(播種期)>육묘일수(育苗日數)>파종밀도(播種密度)>시비량(施肥量)의 순(順)으로 컸으며 조기파종시(早期播種時)에는 상자당(箱子當) 200g의 파종량(播種量)과 4g까지의 시비량하(施肥量下)에서 알맞은 치묘육성(稚苗育成)이 가능(可能)하였고 적당(適當)한 중묘(中苗)는 25일간(日間)의 육묘시(育苗時)에는 50g의 박파(薄播)에서, 그리고 35일묘(日苗)에서는 100~125g 범위(範圍)의 파종밀도하(播種密度下)에서 육성가능(育成可能)하나 45일묘(日苗)는 지나치게 웃자라 기계이앙용(機械移秧用)으로는 부적당(不適當)하였다. 만파시(晩播時)에도 같은 경향(傾向)이나 처리간차이(處理間差異)가 확대(擴大)되었으며 치묘(稚苗)는 상자당(箱子當) 100g 이하(以下)의 박파조건(薄播條件)에서 육성가능(育成可能)하였고 100내지(乃至) 150g의 파종밀도(播種密度)에 25일간(日間) 육묘(育苗)하므로서 알맞은 중묘(中苗)를 얻을 수 있었으나 35일(日) 이상(以上) 육묘일수(育苗日數)를 연장(延長)하면 지나치게 생장(生長)하거나 도장(徒長)하였고 성묘비율(成苗比率)도 현저(顯著)히 저하(低下)하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.233-233
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• 2017

Algal communities are important to maintain the aquatic ecosystems function. Algae have short life cycles, they respond quickly to environmental change and their diversity and density can indicate and the quality of their habitat. The bloom forms before the rice seedings have emerged, it may present a physical barrier that prevents the seedlings from penetrating the floodwater. Wind may also move the algal bloom, pushing the young plants beneath the surface. Another harmful action develops when the water dries up and the algae form a layer at the bottom of the field. The layer envelops the seedlings, which are not yet deeply rooted, and drag them to the surface when the water is let in again. Soil utilization pattern can be the mail facter affecting soil physico-chemical properties, especially in soil phosphorus (P). Solid content of the algae culture solution increased with the increase in the nitrogen rather the phosphors concentration. Phosphoric acid was treated with conventional treatments (100-0%, before transplanting time-tillering stage), 50-50%, 0-100%, and un-treated. The herbicide was treated on the 7 DAT (day after transplanting). Green algae samples were collected 20 DAT. Total phosphoric acid was the highest at 0.06 in 50-50% treatment in 20 DAT. The amount of green algae was about twice (9.8 mg/20ml) that of un-treated. Total number of green algae was 54 species(Green algae 35 species, Euglena 9 species, Stone wheel 10 species). Among the phosphoric acid treatment methods, the number of occurrences of green algae were the highest with 39 species in 0-100%, followed by 50-50%, 28 species, conventional treatments, 22 species, non-treatment, 18 species, respectively. Rice Yield was not significantly different by phosphoric treatment time, but slightly higher than un-treated. The maximal algal biomass was observed about 2weeks or 1 month after transplanting; the subsequent decrease of the biomass was related to the consumption by grazers and to a deficient light under the rice canopy. Maximal algal growth was observed just before tillering. To estimate the suitable method of phosphorus application in puddled-soil drill seeding of rice, available phosphorus appearance of algal water bloom, and rice yield were investigated in paddy soil of rice-barley double cropping system.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.234-234
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• 2017

Recent abnormal weather, especially continued rainfall during sowing season causes difficulty in proper sowing of wheat and delayed sowing after November 15 is concerned about freezing damage during winter, resulting in reduction of wheat yield. To correspond government policy of crop sufficiency improvement and produce and supply raw wheat and barley steadily, expansion of cultivation area is necessary and spring sowing of wheat is required. To obtain basic information on the improvement of spring sown wheat and barley production, comparison and path coefficients analysis was conducted for yield and yield related components from autumn and spring sown wheat and barley. Path analyses were known as very useful in clarifying the effects of yield components on grain yield formation, which were not accurately reflected in simple correlation anaylses. Most cultivated 5 wheat and 9 barley cultivars were sown on October and February at Cheon-ju province according to standard sowing method. For the spring sowing of wheat and barley, the varieties having vernalization degree I~III are seeded in the mid of February and seeding rate is 200~250kg/ha which is increased by 25% than autumn sowing. N-fertilizer of 95 kg/ha and the same amount of P, K dressed in autumn are applied at once as basal fertilizer. The magnitude of direct effect in each yield components on yield was in sequence as follows. In autumn wheat, grain number per $spike{\geq}$ the number of spike per $m^2$>1000-grain weight and in spring wheat, grain number per $ spike{\geq}the$ number of spike per $m^2$> 1000-grain weight. In autumn naked barley, 1000-grain weight> the number of spike per $m^2$, grain number per spike and in spring barely, the number of spike per $m^2$> grain number per spike > 1000-grain weight. In autumn covered barley, grain number per spike>the number of spike per $m^2$ and in spring coverd barley, the number of spike per $m^2$> grain number per spike, 1000-grain weight. In autumn malt barley, the number of spike per $m^2$>1000-grain weight and in spring malt barley, the direct effects of three yield components were similar. According to the path analysis of yield components for spring sown wheat and barley, it was suggested that adequate number of spike per $m^2$ was most important factor for yield increase.

• 한국산림과학회지
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• 제87권3호
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• pp.383-390
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• 1998

암절취(岩切取) 손(毁損)비탈면에 환경생태적(環境生態的)으로 안정(安定)될 수 있도록 적용이 가능한 산림표층토(山林表層土)를 이용한 종비토(種肥土)뿜어붙이기공법(工法)용 속성연화자재(速成緣化資材)(녹화토양(綠化土壤))의 시공효과(施工効果)를 분석하기 위하여, 1997년 4월에 현장 시공을 실시하였다. 3가지 유형의 녹화토양에 따른 식생 및 토양의 특성을 파악하기 위하여 완전임의배치법으로 실험(實驗)을 실시한 결과를 요약하면 다음과 같다. 산림토양(山林土壤)과 마사토, 퇴비, 슬러지, 연소재 등의 자재를 이용하여 조재한 3가지 녹화토양(綠化土壤)의 입도(粒度)분포는 큰 차이가 없었으나, 산림토양을 첨가함에 따라서 토양가밀도(土壤假密度)는 높아졌고, 토양경도(土壤硬度)는 시공 후 초기단계에서는 약간 증가하였으나, 식생의 활착에 따라서 점진적으로 감소하였다. 시공 1개월 후 전체 식생의 출현개체수(出現個體數)는 3,000본/$m^2$ 이상으로 나타났으며, 산림토양을 첨가함에 따라서 공시종과 자연적으로 발생한 식생과의 경쟁으로 인하여 출현개체수는 급격히 감소하였다. 산림토양을 첨가함에 따라서 초기에 파종한 공시종 외에 산딸기, 왕바랭이, 망초, 방울토마토 등 약 6종/$m^2$ 이상이 자연적으로 출현하였다. 비탈면 식생의 종다양성(種多樣性) 회복이라는 측면에서 산림토양의 이용가능성은 높았으며, 산림토양을 녹화자재(녹화토양)로 이용하기 위해서는 산림토양의 특성(잠재종자원(潛在種子源), 토성(土性), 유기물(有機物) 특성) 등을 면밀히 분석하여 배합비율을 결정하는 것이 타당할 것이다.

• 한국유기농업학회지
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• 제11권4호
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• pp.103-115
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• 2003

In order to investigate the possibility for use to control environmental pollution, Kenaf(Hibiscus cannabinus L.) was used to obtain information of their growth and $CO_2$ response under different temperatures and $CO_2$ concentration. The highest percentage of germination and aboveground dry mass of Kenaf were found at 30$^{\circ}C$ and 35$^{\circ}C$ by 89.0% and 3.2g, respectively under different temperatures. The amount of $CO_2$ absorption and aboveground dry mass production of Kenaf were higher than those of maize during the whole growing period and the last sampling of aboveground dry mass of Kenaf and maize were 252.9g and 200.8g, respectively. The highest plant height was found at 400ppm by 131.0cm and the next was in the order of 600ppm by 1293cm, and 800ppm by 108.8cm. Leaf area was higher in the order of 400ppm > 600ppm > 800ppm, whereas leaf dry mass was in the order of 800ppm > 600ppm > 400ppm under different $CO_2$ concentration, showing that leaf became thicker as $CO_2$ concentration was increased. Days from seeding to flowering became shorter by 13 days in 35/25$^{\circ}C$ compared with 25/15$^{\circ}C$ between two temperature regimes and they also became shorter as $CO_2$ concentration was increased. Aboveground dry mass was higher in 35/25$^{\circ}C$ than that of 25/15$^{\circ}C$ between two temperature regimes. while it was increased in the order of 800ppm > 600ppm > 400ppm as CO2 concentration was increased. Temporal changes of leaf dry mass during growth period showed no difference between $CO_2$ concentration in 25/15$^{\circ}C$ , but the highest of it was found at 800ppm in 35/25$^{\circ}C$. The highest temporaI increase of root dry mass was found at 800ppm in 25/15$^{\circ}C$, but 35/25$^{\circ}C$ showed no difference between different $CO_2$ concentration.

• 한국작물학회지
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• 제50권1호
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• pp.16-21
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• 2005

This study was conducted to establish the elaborate nitrogen fertilization method to enhance N use efficiency in direct-seeded rice on flooded paddy. The nitrogen uptake by rice plants was insignificant until 25 days after seeding, and increased gradually thereafter. During this early growth stage, rice plants absorbed only the $4\%$ of basal applied N, while the $45\%$ of N fertilizer remained in the paddy soil. The absorption of basal N by rice plants was almost completed at 46 days after application. Nitrogen top-dressed at 5-leaf stage was well matched to crop nutrient demand, so it could be absorbed so actively in 8days after application. As a result, we could cut down the amount of N fertilizer to $36\%$ of the basal N level without significant difference in yield. Plant recoveries of fertilizer $^{15}N$ applied with different application timings were $7.8\%$ for basal, $9.4\%$ for 5-leaf stage, $17.1\%$ for tillering stage, and $23.4\%$ for panicle initiation stage, respectively. When urea was applied with nitrogen fertilization practice based on basal incorporation (BN), plant recovery of $^{15}N$ at harvest was $31.0\%$, which was originated from $13.7\%$ for grain, and $21.3\%$ of the fertilizer $^{15}N$ remained in the soil, and the rest could be uncounted. Plant recovery of fertilizer $^{15}N$ applied with nitrogen fertilization practice based on topdressing at 5-leaf stage (TN), where N rate was reduced by $18\%$ compared with BN, was $35.1\%$ (grain $15.6\%$), and $19.9\%$ of the fertilizer $^{15}N$ remained in the soil, and the rest could be uncounted. TN showed a higher $^{15}N$ recovery than BN because it was to apply N fertilizer at a time to well meet the demand of rice plant direct-seeded on flooded paddy. We concluded that TN would be the nitrogen fertilization method to enhance N use efficiency in direct-seeded rice on flooded paddy.

• 한국작물학회지
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• 제15권
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• pp.69-75
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• 1974

1. 질소시비를 하지않은 콩에서 개화기이후의 토양수분부족은 충분한 생육을 한 콩보다 생육일수가 3-4일 단축되었다. 2. 엽면적은 발아후 40일경까지는 처리의 영향이 컸다. 3. 경장 경경 분지수 분지장은 파종후 70일경에 거이 완성되었고 초기생육이 불량한 경우 가장 떨어졌다. 4. 질소 증시가 협수를 증가시키지 못했고 개화기의 토양수분부족은 협수를 심히 감소시켰고 이러한 콩은 분지협보다 주경협이 많았으며 또 다입협율이 높았다. 5. 주경절입별 착입수는 3-4절과 10-12절에 많았다. 3-4절에는 충분한 생육을 한 콩에서 많았고 10-12절에는 빈약한 생육을 한 콩에서 많았다. 6. 1주입수가 적은콩이 백입중은 높았다. 7. 단백질함량은 백입중이 낮은콩(N$_{0}$D$_4$)에서 가장 낮았고 유지는 1주입수가 적은콩에서 낮았다.

• 한국초지조사료학회지
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• 제22권1호
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• pp.1-8
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• 2002

Chufa(Cyperus esculentus L.)는 고온성 사초과 식물의 일종으로 여름기간에 잘 자란다. 지상부는 주로 잎으로 구성되어 있으며 지하부는 수염뿌리가 뭉쳐 나있고 끝에 괴경이 달린다. 파종 당년에는 출수가 되지 않고 괴경을 많이 생산한다. 번식은 괴경에서 분얼이 많이 나오는 영양번식을 하며 이 분얼이 다발모양(bunch type)의 포기를 형성한다. 성숙기의 초고는 73~75cm 전후이며 7월 중순에 거의 성장이 완료된다. 포기당 분얼의 수는 7월말까지 급격히 증가하고 8월 이후는 서서히 증가하지만 생장이 빈약하였다. 지상부의 최종 생초수량은 40.3ton/ha, 건물수량은 12.2ton/ha이다. 재생력은 생장초기에는 강하지만 2회 예취후는 재생력이 급격히 떨어진다. 무예취구에서 최종 수확기의 포기당 괴경의 수는 722개, 1$m^2$ 당 생체량은 4.2kg, 건물량은 1.9kg이었다. 예취구의 경우 괴경의 생산량은 예취시기가 늦어질수록 감소하였으나 8월 이후에는 이미 괴경생산이 상당히 진행된 것으로 보였다. chufa의 영양생장기 지상부 사료가치는 우수하였으나 생장이 진행될수록 낮아졌다. 최종 수확한 지상부의 조단백질, NDF, ADF, DMD, TDN 함량은 각각 6.1%, 81.5%, 39.8%, 33.2%39.40%, 괴경의 영양성분은 각각 6.0%, 68.3%, 15.5%, 50%, 51.8%였으며, 특히 지방 함량은 16.2%로 높았다.