Hay-making is one of the most common way for forage preservation in livestock industry. The quality and production of hay could be affected by various factors. This experiment was conducted to investigate the effect of tedding time and frequency on drying rate and feed value of forage rye (Secale cereale L.) hay. Rye was harvested on heading stage using mower conditioner. Hay was tedded at each set hour(09:00, 13:00 and 17:00) and sampled at each set hour to determine dry matter (DM) content. After two months’ preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter digestibility), TDN (total digestible nutrient), RFV (relative feed value), DM loss, visual scores and total fungi count were determined for estimation of hay quality. Tedding was necessary for both speeding up drying rate and improving forage quality. Tedding at 17:00 showed lower NDF content (p<0.05), and also higher RFV value was found compared with tedding at 9:00 and 13:00 (p<0.05). On the other hand, it was observed that more DM losses would be found when tedding later (p<0.05). Tedding in 1~3 times per day were lower in ADF and NDF content (p<0.05), increased CP, TDN and RFV (p<0.05), got less DM loss (p<0.05), and contained less fungi during conservation compared with no tedding (p<0.05). On the other hand, tedding too frequent caused more DM loss (p<0.05). In conclusion, for shorter drying process and higher quality of forage rye hay, tedding at 13:00∼17:00 for 1∼2 times per day was recommended in this study.

The aim of this present study was to investigate the impact of different seeding rate and nitrogen fertilizing levels on the seed yield and feed value of oats(Avena sativa L.) grown in Gyeongbuk area for two years. The experiment was arranged in split plot design with 3 main plots(100, 130 and 160 kg of seed/ha) and 4 subplots(0, 50, 70 and 90 kg N/ha), with 3 replicates. Heading, flowering, and maturing dates of oats sown in spring 2017, delayed by two days compared to that of spring 2016, and the plant height of spring 2017 were significantly shorter than that of spring 2016(18.1 ~ 23.4 cm). In addition, the highest number of stems and number of panicles according to different seeding rate and nitrogen fertilizing levels were achieved with the seeding rate of 160 kg/ha and 90 kg of N/ha in 2016 and 2017, respectively. In case of seed yield as affected by different seeding rate, the highest seed yield was achieved with a seeding rate of 130 kg/ha(p<0.05), and based on nitrogen fertilizing levels, the highest yield was obtained in 50 kg of N/ha compared to others. The crude fiber(CF), neutral detergent fiber(NDF) and total digestible nutrients(TDN) of oats cultivated and harvested in spring 2016 and 2017 according to different sowing rate were the highest in the seeding rate of 130 kg/ha. The crude protein(CP) content and total digestible nutrients(TDN) of 2016-2017 as influenced by nitrogen fertilizer levels were the highest in the nitrogen fertilizer level of 90 and 50 kg N/ha, respectively. In conclusion, the proper seeding rate and the optimal nitrogen fertilizing level in Gyeongju, Gyeongbuk province were considered to be the most appropriate in 130 kg/ha and 50 kg of N/ha, respectively.

Hay-making is one of the most common forage preservation practices in livestock operations. The objective of hay-making is to minimize nutrient loss by shortening field drying time. Measuring the impacts of cutting height of forage crop is necessary to optimize hay production balancing yield and quality, in order to obtain substantial biomass increase through harvest of regrowth. This experiment was conducted to investigate the impact of cutting height of rye (Secale cereale L.) on drying rate and hay quality. Heading stage rye was harvested at 8cm or 15cm stubble heights. Hay was daily tedded at 09:00 and sampled at 09:00, 13:00 and 17:00 to determine moisture content (MC). After two month of preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter disappearance), TDN (total digestible nutrient), RFV (relative feed value), DM (dry matter) loss, visual scores and total fungi count were determined for estimation of hay quality. Cutting height at 15cm could enhance the drying rate and CP content (p<0.05), but also increases DM loss (p<0.05) compared to cutting at 8cm. Cutting heights did not affect ADF, NDF, IVDMD, TDN and RFV value (p>0.05). Visual scores of rye hays cutting at 8cm and 15cm, ranged from 83 to 85. Cutting at 8cm tended to maintain higher core bale temperature and fungal count than cutting at 15cm during preservation, but there was no significant difference.

In this study, to apply hydrogen energy to ship engine and to generate effective hydrogen production, we investigated the effects of high temperature H₂SO₄ feed rate and cooling water rate to pump parts with fixed frequency needed to reciprocate motion and a simulation was conducted at each condition. In the fixed frequency and cooling water inlet flow rate of 0.5 Hz and 3.9 kg/s, we changed the high temperature H₂SO₄ flow rate to 47.46 kg/s (it is 105 % of 45.2 kg/s), 49.72 kg/s (110 %), and 51.98 kg/s (115 %). Also, at 0.5 Hz and 45.2 kg/s of frequency and high temperature H₂SO₄ flow, the thermal hydraulic analysis was performed at the condition of 95 % (3.705 kg/s), 90 % (3.51 kg/s), and 85 % (3.315 kg/s). In overall simulation cases, the physical properties of materials are more influential to the temperature increase in the pump part rather than the changes on the feed rate of high temperature H₂SO₄ and cooling water. A continuous operation of pump was also capable even if the excess feed of high temperature H₂SO₄ of about 15 % or the less feed of cooling water of about 15 % were performed, respectively. When the increasing feed of high temperature H₂SO₄ of up to 5 %, 10 %, and 15 % were compared with base flow (45.2 kg/s), the deviation of time period rose to a certain temperature and ranged from 0 to 4.5 s in the same position (same material). In case of cooling water, the deviation of time period rose to a certain temperature and ranged from 0 to 5.9 s according to the decreasing feed changes of cooling water at 5 %, 10 %, and 15 % compared to a base flow (3.9 kg/s). Finally, the additional researches related to the two different materials (Teflon and STS for Pitch and End-plate), which are concerned about the effects of temperature changes to the parts contacting different materials, are needed, and we have a plan to conduct a follow-up study.

본 시험은 제주지역의 화산회토양에서 인산시비량 차이(0, 50, 100, 150, 200, 250kg/ha)에 따른 제주재래 대두의 생육형질, 수량 및 사료가치 변화를 구명하기 위하여 2002년 5월 11일부터 2002년 9월 10일까지 시험하였다. 인산시비량이 0에서 250kg/ha로 증가함에 따라 개화기까지의 일수는 92일에서 97일로 지연되었고, 초장은 109cm에서 124cm로 커졌다. 분지수, 엽수, 경직경, 근장 및 근중 등도 인산시비량이 증

본 시험은 제주지역에서 질소시비량 차이(0, 50, 100, 150, 200, 250kg/ha)에 따른 제주조의 생육반응, 수량 및 사료가치를 구명하기 위하여 2000년 5월 1일부터 8월 25일까지 수행한 결과를 요약하면 다음과 같다. 출수기까지의 일수는 92일에서 98일로 질소 시비량이 증가할수록 출수기까지의 일수는 지연되는 경향이었다. 초장은 무비구에서 96cm였던 것이 질소시비량이 증가함에 따라 점차적으로 커져서 200kg, 250kg/ha 시비

충남 예산에서 호밀을 답리작으로 재배할때 파종량과 예취기간가 수량 및 사료가치에 미치는 영향을 요약하면 다음과 같다. 1. 파종량이 많아질수록 호밀의 초장과 단위면 적당 경수는 증가하였으며 건물률은 감소하였다. 2. 청예 및 건물수량은 파종량이 많을수록 높았으며 예산에서 청예수량이 가장 높았던 예취기는 5월 15일, 건물수량이 가장 높았던 예취기는 5월 25일 이었다. 3. 파종량이 많을 수록 그리고 예취시기가 늦을수록조단백질, 가급태단백질 및 가소화단백질 함량은 감소하였으며, 반면에 조섬유함량(ADF와 NDF)은 증가하였다. 4. 파종량이 많을 수록 그리고 예취시기가 늦을수록 총가소화영양분(TDN) 함량과 상대적 사료가치는 감소하였다. TDN 수량은 파종량 18-28kg/10a, 5월 15-25일 수확시 가장 높았다. 5. 호밀의 에너지 함량은 파종량이 많을수록 그리고 예취시기가 늦을수록 감소하나, 단위면적당 에너지 생산량은 ENE와 NEL은 23kg/10a 파종-5월 15일 수확할때, NEM은 18kg/10a 파종-5월 15일 수확할때 가장 높았다. NEG는 18-28kg/10a 파종-5월 5일 수확할 때 가장 높았다.