• Corrosion Science and Technology
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• 제21권2호
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• pp.121-129
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• 2022

A study on water-based epoxy coated on mild steel using the electroplating method was conducted to optimize the process parameters for dry film thickness to achieve superior paint quality at optimal cost in an automotive plant. The regression model was used to adjust various parameters such as electrode voltage, bath temperature, processing time, non-volatile matter, and surface area to optimize the dry film thickness. The average dry film thickness computed using the model was in the range of 15 - 35 ㎛. The error in the computed dry film thickness with reference to the experimentally measured dry film thickness value was - 0.5809%, which was well within the acceptable limits of all paint shop standards. Our study showed that the dry film thickness on mild steel was more sensitive to electrode voltage and bath temperature than processing time. Further, the presence of non-volatile matter was found to have the maximum impact on dry film thickness.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.214-220
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• 2005

The study was conducted to compare the dry matter intake and digestibility of Atriplex halimus (AH) and Atriplex nummularia (AN) and determine the proper proportion of saltbushes for partial replacement of alfalfa hay in the diets of Awassi sheep. The foliage of AH and AN were hand-plucked, air-dried in shade and then chopped mechanically similar to alfalfa hay. Two trials were conducted separately to determine voluntary feed intake and digestibility of saltbush browse. In the first trial, fifteen 8 month old Awassi lambs were distributed into 3 equal groups, and each animal was housed in individual pen. Each group received one of three dietary treatments: chopped alfalfa hay (H), dried foliage of Atriplex nummularia or foliage of Atriplex halimus. In the second trial, twentyseven 12 months old Awassi male lambs were randomly selected, distributed into nine equal groups, and housed into metabolic crates. Each group of animals received one of nine dietary treatments: alfalfa hay, AN, AH and different proportions (25, 50 and 75%) of AN or AH mixed with alfalfa hay. Forage type had a significant (p<0.001) effect on dry matter intake (DMI) and growth rate of lambs of the voluntary feed intake trial. Lambs receiving the alfalfa hay diet showed high DMI and high growth rate compared to those fed the diets containing saltbush. In the digestibility trial, dietary treatments had significant (p<0.05) effect on DMI, dry matter digestibility (DMD) (p<0.01) and organic matter digestibility (OMD) (p<0.01). The inclusion of AN in the diet up to 50% had no significant effect on DMI and DMD, whereas the inclusion of AH above 25% reduced DMI, DMD and OMD. The treatments had significant (p<0.05) effect on water intake and on live weight changes of lambs. Except for the diet containing 25% of AN browse, all lambs fed diets containing the saltbushes exhibited loss in body weight. The nutritive value of Atriplex nummularia foliage is better than that of A. halimus and it is possible to replace up to 50% of alfalfa hay by A. nummularia without negative effects on intake and digestibility of dry matter.

• 한국초지조사료학회지
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• 제12권3호
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• pp.178-184
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• 1992

Five varieties of silage corn were cultivated to compare the growth characteristics and productivity. Corn varieties were Pioneer 3144(P 3144), 3160(P 3160), 3282(P 3282), 3352(P 3352) and Suweon 19 (S 19). The corns were seeded on May 2 and harvested on August 15, and measured the plant height, leaf length, leaf width, stem diameter, and yields of fresh and dry matter. The results obtained were as follows: 1. Plant height of P 3352 and P 3144 grown about 280cm throughout the experimental period was the tallest(P<.Ol), and those of P 3160, P 3282 and Suweon 19 ranged from 246.3 to 256.0 cm. 2. Leaf length is the longest in P 3352 and the shortest in P 3282(97.63cm vs 84.17cm), and there was significant(P<.Ol) difference between corn varieties. 3. Stem diameter was the longest in P 3144 and the shortest(P<.Ol) in P 3352(3.28cm vs 2.66cm). 4. P 3144, P 3282 and P 3352 had the greatest(P<.Ol) fresh matter yields per 10a in leaf, stem, and ear and whole plant, respectively. 5. Dry matter yield of P 3282 was the greatest(P<.Ol) in stem(1,080.6 kg/lOa) and leaf(304.5 kg/lOa), and that of P 3352 was the greatest in ear(864.1 kg/lOa) and whole plant yield(2,021 kg/lOa). 6. Ratios of respective part of corn to total dry matter were ranged from 12.7 to 17.8 76 for leaf, 44.5 to 66.9% for stem and husks, and 16.9 to 42.8 % for ear, and the highest in P 3160, P 3160 and P 3352, respectively. Consequently, P 3352, P 3144 and P 3282 shown high productivity in dry matter yield could be recommended as a reliable corn varieties for silage.

• 한국잡초학회지
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• 제9권3호
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• pp.177-182
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• 1989

1. 비료성분별(肥料成分別)의 올챙고랭이 종간경합특성(種間競合特性) 질소시비량(窒素施肥量) 증가(增加)로 두 식물종(植物種) 모두 초장(草長), 경수(莖數), 건물중(乾物重)이 증대(增大)되었으나 초장(草長)과 경수증가(莖數增加)는 올챙고랭이보다 벼가 민감하였다. 또한 가리시비량(加里施用量) 증가(增加)로 벼는 전반적인 생장(生長)이 촉진(促進)되었으며, 올챙고랭이는 경수(莖數)와 건물중(乾物重) 형성(形成)에서 효과적(效果的)이었다. 2. 수심차이(水深差異)에 따른 올챙고랭이의 종간경합특성(種間競合特性) 두 식물(植物) 모두 밭 조건(條件)보다는 담수심(湛水深)이 깊어질수록 초장(草長)이 커졌으나, 경수(莖數)(분얼수)와 건물중(乾物重)에 있어서는 올챙고랭이의 경우 밭 조건(條件)일수록 벼에 대한 우위성(優位性)이 있었으나 수심(水深) 6~8cm 이상에서는 두 식물종(植物種) 모두 분얼수 및 건물중(乾物重)이 심하게 감소(減少)하였다. 3. 광제한(光制限)에 따른 올챙고랭이의 종간경합특성(種間競合特性) 광제한(光制限)으로 단식(單植)보다 혼식(混植)에서 두 식물(植物) 모두 경수분화(莖數分化)가 비슷한 비율(比率)로 감소(減少)되는 경향(傾向)이었으나 채광역(採光域)의 경엽장(莖葉長)과 경엽중(莖葉重)의 증가폭(增加幅)은 벼보다 올챙고랭이가 컸다. 차광역(遮光域)의 지하부증(地下部重)은 벼보다 올챙고랭이가 단식(單植)보다 혼식(混植)에서 현저히 감소(減少)하는 경향(傾向)이었다.

• 한국자원식물학회지
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• 제9권3호
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• pp.274-278
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• 1996

본 실험은 포장과 포트재배에서 토양시비수준(土壤施肥水準), 온도(溫度) 및 광조건(光條件下)에서 건물생산량과 광합성(光合成) 속도의 차이를 측정분석하여 야콘의 적정생장(滴定生長) 조건(條件)을 밝히고자 실시하였다. 1. 포장에서의 시비수준별 건물생장율은 무처리구 보다 퇴비구에서 높게 나타났으며, 구근의 건물중은 무처리구와 질소처리구와는 큰 차이를 보이지 않았다. 2. 최대 엽광합성 속도는 퇴비구(S-1)에서 17.3mg $CO_2gdm^{-2}s^{-1}$로 다른 질소 처리구 보다 높았으au, 무처리구의 엽광합성 속도가 가장 낮았다. 3. 광환경(光環境) 조건(條件)에 따른 퇴비구와 무처리구의 엽광합성 속도차이는 뚜렷하게 차이가 났으며 광포화점은 $1200{\pm}50{\mu}molm^{-2s^{-1}$이었다. 4. 광합성속도는 $34{\pm}3^{\circ}C$ 정도에서 높은 반면 $28^{\circ}C$ 정도 이하에서는 기공저항에 의하여 엽광합성 속도가 낮았다.

• 한국작물학회지
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• 제39권5호
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• pp.458-464
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• 1994

콩 유전자형간 상호접목을 통하여 지상부 생육과 콩깍지에 대한 종실건물중 비율에 미치는 영향을 비교 검토하고자, 꼬투리의 비대가 충실한 백운콩과 수원 158호, 꼬투리 크기에 비하여 종실건물축적이 불량한 수집검정콩 강릉재래 및 금릉재래를 공시하여, 자가접목 및 4개 유전자형간 상호접목을 한 후 이식재배시험한 결과를 요약하면 다음과 같다. 1. 지상부의 생육정도와 콩깍지 및 종실건물중은 지상부 유전자형간 유의적인 차이가 인정되었으나, 지하부 유전자형간 차이가 없었다. 2. 백립중 및 꼬투리에 대한 종실건물중 비율도 지상부 유전자형에 의하여 결정되기 때문에, 상대적으로 양분흡수와 밀접한 관련이 있는 지하부 유전자형과는 관계가 적었다. 3. 접목된 개체들의 콩깍지 건물중과 콩깍지에 대한 종실건물 비율은 유의적인 부의 상관관계를 나타내고 있어, 콩깍지 건물중이 클수록 콩깍지에 대한 종실건물 비율이 낮아지는 경향이었다.

• 한국작물학회지
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• 제52권3호
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• pp.249-258
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• 2007

Experiments were conducted with aims to (1) estimate the biomass yield potential, (2) characterize the biomass and digestible dry matter production, and (3) reveal the characteristic seedling establishment of a whole crop rice variety, Nogyangbyeo, in dry- and wet-seeded rice. Maximum aboveground total biomass of Nogyangbyeo was 18 t $ha^{-1}$ in dry-seeded rice and 20 t $ha^{-1}$ in wet-seeded rice. Biomass yield potential of Nogyangbyeo was lower than that of Dasanbyeo. Comparatively, Nogyangbyeo was straw-dependent and Dasanbyeo was grain-dependent for biomass accumulation. Percentage of digestible dry matter (DDM) was higher in panicles than straw. Digestible dry matter yield was determined mainly by biomass yield rather than DDM percentage. Number of seedling establishment in Nogyangbyeo was $73m^{-2}$ in dry-seeded rice and $109m^{-2}$ in wet-seeded rice. Poor seedling establishment of dry-seeded Nogyangbyeo in the field condition was the result of low seed germination under low temperature and poor seedling emergence by deep sowing. Low seedling emergence rate of Nogyangbyeo was attributed mainly to slow elongation growth by slow leaf development and partly to mesocotyl and 1st internode lengths, not to genetically defined leaf length. The slow elongation growth of Nogyangbyeo was the same even in the high daily mean temperature of $24^{\circ}C$. Results suggest DDM yield in rice can be improved simply by increasing biomass and whole crop rice varieties should be adaptable to direct-seeding.

• 한국축산시설환경학회지
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• 제6권1호
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• pp.37-44
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• 2000

A new hose slurry spreader with improved spreading uniformity is developed to distribute the slurrynear to the soil surface and to reduce odor problems. The precision of distributed slurry was investigated using 3 types of slurry and found to be dependent on the rotor speed. For the solid matter separated fluid containing 0.1% of dry matter rotor speed of 150 rpm showed best uniformity with CV of 10% In the case of slurry from dairy cattle which contains 8.2% of dry matter high rotor speed of 330 rpm showed best result with CV of 7.2% Also swine slurry which has a 13.6% of dry matter content showed the best result of 8.1% CV at the high rotor speed of 250rpm. A high rotor speed generates enough pressure in the central distributor and as a result uniform distribution of slurry can be achieved. In conclusion it is highly recommended rotor speed of 300 rpm to get the best performance.

• 유기물자원화
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• 제2권2호
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• pp.53-63
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• 1994

예취빈도가 다른 조건에서 무기태 질소와 액상구비의 시용수준이 Reed canargrass 의 건물수량에 미치는 영향을 액상구비의 질소이용효율을 중심으로 검토하였다. 무기태 질소의 시용에 대한 액상구비의 상대건물수량은 연간 3회 예취구에서 84.3%, 4회 예취구에서 77.9%, 그리고 5회 예취구에서 81.2%를 나타내어 액상구비의 시용효과가 높았다. 무기태 질소의 건물생산효율(kgDM/kgN)은 모든 예취구에서 30kg/ha/cut 수준에서 가장 높았으며, 예취빈도에서는 3회 예취구가 질소 1kg당 23.9kg의 건물수량을 나타내어 다른 예취구보다 높았다. 그러나 전질소량(kgTN/kgN) 의 증가에서는 예취빈도에 따른 차이가 인정되지 않았다. 액상구비의 건물생산효율(kgDM/kgN) 은 3회와 4회 예취구에서는 30kg/ha/cut 수준, 5회 예취구에서는 60kg/ha/cut 수준에서 가장 높았으며, 전질소량(kgTN/kgN) 에서는 3회 예취구에서 0.11kg이었으나, 4회와 5회 예취구에서는 20kg 이상이었다. 무기태 질소에 대한 액상구비의 상대건물생산효율은 3회 예취구에서 33.1%, 4회 예취구에서 52.1%, 5회 예취구에서 50.0%였으며, 상대전질소량은 3회 예취구에서 28.9%, 4회 예취구에서 51.3%, 그리고 5회 예취구에서 55.3%를 나타내었다.

• 한국환경과학회지
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• 제12권7호
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• pp.735-744
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• 2003

The field observations on a seasonal characteristic of organic matter and its origin in the surface sediment were carried out at 35 stations in Deukryang bay, southern coast of Korean Peninsula from May 1995 to February 1996. The analytical parameters were mud temperature, ignition loss(IL), chemical oxygen demand(COD), pheopigment, sulfide and water content. The origin and seasonal dynamics of organic matter in Deukryang Bay were analyzed by COD/IL, COD/sulfide ratio and principal component analysis(PCA). As a results of the mud temperature fluctuated between 2.1$^{\circ}C$ with the lowest mean 4.6$^{\circ}C$ in winter and 27.6$^{\circ}C$ with the highest mean 25.5$^{\circ}C$ in summer. The range of ignition loss(IL) was from 3.1% in autumn to 21.5% in winter. Chemical oxygen demand(COD) showed the highest mean value of 8.45 mg/g dry in spring within the range of 2.90∼18.21 mg/g dry, while it showed the lowest value of 4.33 mg/g dry in autumn within the range of 0.67∼10.37 mg/g dry. Pheopigments showed the highest mean value of 9.04 $\mu\textrm{g}$/g dry in autumn within the range of 1.36∼20.44 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 2.20 $\mu\textrm{g}$/g dry in summer within the range of 0.33∼11.36 $\mu\textrm{g}$/g dry. The range of total sulfide (H$_2$S) was from no detect(ND) to 3.30 mg/g dry in spring. And water content showed the annual mean value of 43.6% within the range of 23.6∼54.9%. The source of organic matter by COD/IL and COD/sulfide ratio in Deukryang Bay had been producted by primary producer in sea water areas except the areas effected by small stream, domestic and animal wastes. And the analytical results of PCA was able to be divided into three different regions. The former was characterized by the shallow depth and authigenic organic matter from phytoplankton in northwest area and northeastern inner bay, the secondary was done by deeper depth and allochthonous one from lands in southeast area and eastern entrance of bay, and the latter was done by authigenic one from the farm of seaweeds such as, sea cabbage, sea mustard etc in western entrance of bay. But a study on the relationship between sulfide and COD concentration in the northeastern inner bay which was characterized by the water stagnation will to take much more studying including major constituents of organic matter in the future.