The objective of this study was to determine the effect of harvesting time of rice on growth characteristics and dry matter yields of Italian ryegrass (Lolium multiflorum Lam., IRG) ‘Kowinearly’ after seeding them in paddy field. Experiments were performed in National Institute of Animal Science, RDA (Cheonan, Choongcheongnam-do province of Korea) for four years (2011~2014). Italian ryegrass variety ‘Kowinearly’ was seeded at experimental paddy fields before rice harvest in late September. Rice were harvested at 10, 20, and 30 days after seeding of IRG. As the harvest time of rice became later, the number of tillering before winter was reduced and IRG plant length before winter was shorter. The dry matter yield of IRG was also reduced. When rice were harvested at 20 days and 30 days after sowing of IRG compared to the rice harvested in autumn at 10 days after sowing of IRG, the number of tillering for IRG before winter was decreased by an average of 19% and 40%, respectively. The winter survival ratio of IRG was decreased by an average of 13% and 19%, respectively. Their dry matter yields were also reduced by an average of 8% and 19%, respectively. The heading date was different from each other in three years. The plant length at the time of IRG harvest in the spring was not significantly different among treatment groups. Taken together, our results suggest that when Italian ryegrass is grown in paddy fields by the method of ‘seeding of IRG before rice harvest’, rice should be harvested as soon as possible after sowing of IRG ‘Kowinearly’ in the autumn to increase forage productivity.

The objective of this research was to determine the effects of harvesting frequency and fertilization levels on botanical composition, dry matter yield, and forage feed compositions of Alpine grassland at 800 m altitude. This research lasted for three years at National Alpine Agricultural Research Institute in Pyeongchang with two harvesting frequency schedules (two and three times annually) and two levels of fertilizer application (conventional level of fertilizer at 280-200-240 kg/ha and a lower level of fertilizer at 200-200-200 kg/ha for N, P2O5, and K2O). Mixture combinations with seeding rate (kg/ha) were as follows: Orchardgrass 18, Tall fescue 9, Timothy 8, Kentucky bluegrass 3, and Ladino Clover 2. The gramineae ratio ranged from 93.2 to 95.3%. Therefore, gramineae forage was considered as the dominant plant in this experiment. No significant (p>0.05) difference was observed in forage dry matter yield between the two harvesting frequency treatments (two times at 9.8 ton/ha and three times at 8.6 ton/ha). However, forage dry matter yield in the two times of harvesting frequency tended to be greater than that in the three times of harvesting frequency. Significantly (p<0.05) higher forage dry matter yield in the standard fertilization level group than the lower fertilization level group (9.8 ton/ha vs. 8.7 ton/ha) was observed. However, there was no significant (p>0.05) difference in forage crude protein concentration between the two harvesting frequency treatment groups, although the concentration in the group with three times of harvesting frequency tended to be higher. In contrast, crude fiber concentration in the group with two times of harvesting frequency tended to be higher, although the difference was not statistically significant (p>0.05). Crude protein, ether extract, crude fiber, and organic matter concentrations were not significantly (p>0.05) different between the two groups with different fertilization levels. Based on these results, it was concluded that the group with two times of harvesting frequency with conventional fertilization level might be proper for obtaining better forage productivity for Alpine grassland at 800 m altitude.

This study was conducted to find out the effects of Improvement of Botanical Composition Technology (IBCT) on the forage production and ecological characteristics in a Rumex acetosella-dominated hilly pasture in Pyeongchang, in a period from August 2013 to the end of growing season in October 2015. 2MT ha－1 limestone was applied in August 2013 and April 2014. Liming significantly increased soil pH from 4.69 to 5.47 and then the soil pH consistently hovered at 4.91~4.98. For every grazing time, plant height was found to be higher with the application of IBCT as compared with the control. After grazing, no significant difference in plant height was found between the IBCT group and the control. Changes in the botanical composition of grassland can be affected by a lot of circumstances, but application of IBCT decreased Rumex acetosella from 12% to 2%, while also increasing the proportion of pasture. In relation to the botanical composition of grass, orchardgrass and timothy showed the highest percentages throughout the whole study period. The proportion of Kentucky bluegrass increased over time while tall fescue steadily decreased. The totals for grazing days were 58 in 2014 and 55 in 2015. Average herbage dry matter intake was 7,848 kg ha－1 in 2014 and 6,941 kg ha－1 in 2015. Due to the application of IBCT, dry matter productivity showed a significant increase of 59% during the first grazing period in 2014 (3,437 kg ha and 5,460 kg ha in control and IBCT). In 2015, the total dry matter yield of the IBCT group was 51% greater than the control (5,742 kg ha－1 and 8,685 kg ha－1 in control and IBCT). Under acidic soil conditions, red sorrel can grow more strongly than grasses because it has better tolerance in dry and acidic conditions. Therefore, constant management is required in order to keep red sorrel from dominating the hilly pasture. In this study, the application of IBCT was able to effectively control weeds at all points. As a result, total management, including improvement of soil, overseeding, and application of selective herbicide and fertilizer, is needed to maintain excellent grassland conditions due to the limiting effects of environmental factors on grassland productivity.

수확시 숙기와 조제방법이 호밀 라운드베일 사일리지의 건물 손실률과 형태변화에 대한 영향을 구명하기 위하여 3 가지 시험을 수행하였다. 호밀은 3번의 생육단계에 맞춰 수확하였으며 (수잉기, 출수기 및 개화기) i) 예건 (비예건,단기예건, 장기예건)에 따른 변화, ii) 유산균첨가제 (무처리, 첨가제 A 및 첨가제 B) 처리에 따른 변화, iii) 비닐색 (백 색, 흑색, 녹색)에 따른 변화를 관찰하였다. 수잉기 및 비예 건 처리구에서 저장 2개월 후의 형태 변화가 심하게 나타 났다. 그러나 출수기 이후의 수확 처리구에서는 변화정도 가 심하지 않았다. 첨가제 처리는 사일리지의 형태변화와 건물 손실률을 감소시켰다. 건물 손실률은 수확이 지연되 거나 첨가제 처리로 유의적으로 감소되었다. 수잉기 처리 에서는 형태변화가 심하게 관찰이 되었는데 첨가제 처리구 가 비 처리구보다 형태변화가 더 심하게 일어났다. 흑색비 닐 처리는 다른 비닐색에 비해 형태변화가 심하게 일어났 으나 건물 손실률은 비닐색에 따른 차이가 없었다. 상관관 계에서는 수확시 숙기와 예건기간이 형태변화와 정의 상관 이 있는 것으로 나타났다. 이상의 결과를 종합하여 볼 때 건물함량은 사일리지의 형태변화에 영향을 주는 가장 큰 요인으로 나타났다.

Response spectra of a building are made with a SDOF system taking into account a first mode shape, even though higher modes may affect on the dynamic responses of a high-rise building. A soft soil layer under a building also affects on the responses of a building. In this study, seismic responses of a MDOF system were investigated to examine the effects of higher modes on the response of a tall building by comparing them with those of a SDOF system including the kinematic interaction effect. Study was performed using a pseudo 3D finite element program with seven bedrock earthquake records downloaded from the PEER database. Effects of higher modes on the seismic responses of a tall building were investigated for base shear force and base moment of a MDOF system including story shear forces and story moments. Study results show that higher modes of a MDOF system contribute to a reduction of base shear force up to 1/4-1/5 of KBC and base moment. The effect of higher modes is more significant on the base shear force than on the base moment. Maximum story shear force and moment occurred at the top part of a building rather than at a base in the cases of tall buildings differently from short buildings, and higher modes of a tall building affected on the base forces making them almost constant at the base. A soft soil layer also affects some on the base shear force of a high-rise building independently on the soft soil type, but a soft soil effect is prominent on the base moment.

Spatial variations of a seismic wave are mainly wave passage and wave scattering. Wave passage effect is produced by changed characteristics of exciting seismic input motions applied to the bedrock. Modified input motions travel horizontally with time differences determined by apparent shear wave velocity of the bedrock. In this study, wave passage effect on the seismic response of a structure-soil system is investigated by modifying the finite element software of P3DASS (Pseudo 3-Dimensional Dynamic Analysis of a Structure-soil System) to apply inconsistent (time-delayed) seismic input motions along the soft soil–bedrock interface. Study results show that foundation size affected on the seismic response of a structure excited with inconsistent input motions in the lower period range below 0.5 seconds, and seismic responses of a structure were decreased considerably in the lower period range around 0.05 seconds due to the wave passage. Also, shear wave velocity of the bedrock affected on the seismic response of a structure in the lower period range below 0.3 seconds, with significant reduction of the seismic response for smaller shear wave velocity of the bedrock reaching approximately 20% for an apparent shear wave velocity of 1000m/s at a period of 0.05 seconds. Finally, it is concluded that wave passage effect reduces the seismic response of a structure in the lower period range when the bedrock under a soft soil is soft or the bedrock is located very deeply, and wave passage is beneficial for the seismic design of a short period structure like a nuclear container building or a stiff low-rise building.

The seismic performance of school buildings has been a matter of common interest socially and academically. The structural system of the school buildings is representative of the domestic low-rise reinforced concrete moment resisting frames, which apply extensively infills in their masonry walls. The masonry infilled walls are divided into full masonry infill in the transverse direction and partial masonry infill in the longitudinal direction. The masonry infilled walls are usually not included in structural analysis during the design process, but affect significantly the seismic performance because they behave with surrounding frames simultaneously during earthquakes. Many researchers have studied the effect of the masonry infilled walls, but several issues have been missed such as the increase of asymmetry by adding the full masonry infill, the size of the mean strength of the full masonry infill, and short column effect by the partial masonry infill. The issues were analytically investigated and the results showed that they should be checked at least by nonlinear pushover analysis in the seismic performance evaluation process. The results also confirm the weakness of the guideline of Korean Educational Development Institute where the seismic performance is basically assessed without structural analysis.

A series of wind tunnel tests were conducted on 7 super-tall buildings with various polygon cross-sections, including triangle, square, pentagon, hexagon, octagon, dodecagon, and circular. The primary purpose of the present study is to investigate the effect of increasing number of sides on aerodynamic characteristics for super-tall buildings. Wind tunnel tests were conducted under the turbulent boundary layers whose power-law exponent is 0.27. Fluctuating wind pressures from more than 200 pressure taps were recorded simultaneously, and time series of overturning moments were calculated considering tributary area of each pressure tap. The results show that the overturning moment coefficients and the spectral values decrease with increasing number of sides, and the largest mean and fluctuating overturning moments were found for the triangular super-tall building, and the largest spectral values were found for the square super-tall building. The analysis should be conducted more in detail, but currently it can be roughly said that there seems to be a little differences in the aerodynamic characteristics for the super-tall buildings whose number of sides is larger than 5 or 6.

고랭지에서 사일리지용 옥수수의 출현상태와 초기생육은 품종간 차이는 없었으나 년차별 기후변화에 따라 습해 및서리 피해가 발생하였다. 2010년도는 6월 1일 서리가 내렸고, 2011년도는 파종 후 강우가 지속되어 발아 및 초기생육에 영향을 미치게 되었다. 초기생육이 안정적인 품종은국산품종으로 광평옥, 도입종은 P3156 품종이었다. 옥수수의 출사일은 년차 간 평균 5.5일의 차이가 있으며 국산종은 8월 8일부터 8월 12일까지 출사기간이며 도입종은 8월 5일부터 8월 11일까지 출사하여 도입종과 국산종의 출사일은 3~4일 차이가 있었다. 광평옥의 출사일은 8월 8일,P3156 품종은 8월 5일로 비교적 빨리 출사하는 품종이고평안옥과 DK729 품종은 출사기가 늦은 품종이었다. 옥수수 평균 초장은 231 cm 정도이며 국산품종 광평옥은 236cm, 평안옥 237 cm로 초장이 큰 품종이 건물생산량도 많았다. 줄기의 굵기는 전체 평균 23.2 mm, 착수고는 94 cm이었다. 착수고가 낮아 내도복성인 품종은 청안옥 86 cm,33J56 품종 80 cm이었고 강다옥은 101 cm로 착수고가 상대적으로 높았다. 고랭지에서 사일리지용 옥수수 이삭비율은전체평균 39.3%이었으며 국산종보다 도입종이 다소 높았다. 국산품종 중에서 광평옥은 40.1%로 이삭비율이 높았으며 도입종 중에서 P3394 품종이 42.2%로 대등한 이삭비율을 보였다. 사일리지용 옥수수의 생초중은 평균 59.6톤/ha이었으며 국산품종보다 도입품종의 생산성이 다소 높았다.평균 건물수량은 16,653 kg/ha이며 건물수량이 많은 품종순으로 32P75, P3156, 평안옥, P3394, 광평옥이며 건물수량은 각각 18,901 kg/ha, 17,997 kg/ha, 17675 kg/ha, 17194kg/ha, 17188 kg/ha 이었다. 옥수수의 당도는 발효과정에서품질에 미치는 영향이 크며 고랭지에서 평균 당도는 8.1이었다. 국산품종이 8.69로 도입품종 7.42에 비해 평균 1.27높은 것으로 나타났다. TDN 수량에서 32P75 품종은13,381 kg/ha, P3156 품종 12,590 kg/ha, P3394 품종 12,532kg/ha이며 국산품종은 평안옥 12,140 kg/ha, 광평옥 12,036kg/ha로 이들 국산품종은 도입품종과 대등한 TDN 수량을생산할 수 있었다. 고랭지에서 도입품종과 국산품종의 사료가치는 평균 CP 7.8%, 소화율74.2%, NDF 42.4%, ADF23.5%, TDN 70.3%로 대차 없었으며 청안옥의 TDN 함량은 73.3%로 가장 높았다.

건물설계단계에서 신축예정건물의 열차진동영향평가를 위하여 국내의 4개의 열차진동 가속도응답 계측치와 진동전달율(Transmissibility)값을 이용한 이론치를 비교하여 TR값의 적용성을 제시하였다. 이 TR 방법을 통하여 철도인접지역 위치한 신축 예정지반을 선정하고 지반진동 계측을 실시하였다. 계측한 지반의 가진진동수와 수직가속도응답과 신축 예정건물의 바닥슬래브를 MIDAS로 해석한 고유진동수를 통해 진동전달률을 산정한 후 신축건물의 진통예측을 실시하였다. TR을 적용한 가속도응답 예측치를 열차진동 가속도응답 계측치와 비교한 결과 3.61%~37.1% 오차범위에서 있는 것을 확인하였다. 또한 KTX, 경의선, 시멘트 열차 주행 시 지반의 가진진동수는 7.19~10.61Hz 사이에 선명한 피크를 확인 할 수 있다.

본 연구는 한약재 (결명자, 계피, 산초, 감초) 추출물의 반추위내 발효와 미생물 활성에 대한 효과를 구명하기 위하여 수행되었다. In vitro 건물소화율은 계피와 산초 추출물 첨가구에서는 0시간대, 감초 추출물 첨가구에서는 3시간대에 대조구에 비해 현저히 (P<0.05) 낮았다. 한약재 추출물 첨가에 따른 발효 시간대별 휘발성 지방산 조성의 변화는 3시간대에서만 처리간 유의성이 인정되었는데, acetate 비율은 대조구가 천연 추출물 첨가구보다 유의적으로 높았으나, butyrate, isobutyrate, isovalerate 및 valerate은 대조구에서 가장 낮았다 (P<0.05). 미생물 성장율은 발효 3시간대에서 결명자 첨가구를 제외한 한약재 첨가구에서 대조구에 비해 유의적(P<0.05)으로높았으나다른발효시간대에서는차이가없었다 이상의 결과로부터 한약재로 사용되고 있는 계피, 산초 및 감초 추출물을 in vitro 반추위 배양액에 첨가하였을 때, 발효초기에 반추위 미생물의 활성을 억제하는 경향은 있었으나 미생물 성장에 대한 억제 효과는 없는 것으로 나타났다.

논에서 내한성 이탈리안 라이그라스의 조 중 만생 숙기별 Kospeed, Kowinmaster, Hwasan 101호 3품종을 파종시기별로 9월 30일부터 5일 간격으로 10월 20일까지 5처리 파종하여 이듬해 5월 17일에 수확하였고 단위면적당 입모수, 월동률 및 건물수량에 미치는 시험을 2003년부터 2005년까지 수원에서 수행하였다. 논에서 이탈리안 라이그라스 조생종(Kospeed)의 출수기는 5월 7일에서 5월 13일이며 파종일이 늦으면 출수일도