http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김낙근,조용,이계복 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.7
Numerical analysis on the flow induced vibration and flow characteristics in the water gate has been carried out by 2-dimensional unsteady CFD simulation when sea water flows into the port in the river. Effect of gate opening on the frequency and the mean velocity and the vortex shedding under the water gate were studied. The streamlines were compared for various gate openings. To get the frequency spectrum, Fourier transform should be performed. Spectral analysis of the excitation force signals permitted identification of the main characteristics of the interaction process. The results show that the sources of disturbed frequency are the vortex shedding from under the water gate. As the gate opening ratio increases, the predicted vibration frequency decreases. The bottom scouring occurs for large gate opening rather than smaller one. The unstable operation conditions can be estimated by using the CFD results and the Strouhal number results for various gate opening gaps.
柳根燮,金洛根 慶北大學校 1984 農業科學技術硏究所報 Vol.1 No.-
熟田 뽕밭에서 石灰의 施用量이 뽕밭土壤의 化學性 및 뽕잎의 收量에 미치는 影響을 알기 爲해 10a當 消石灰 0, 100, 200, 300kg을 施用한 結果는 다음과 같다. 1. 石灰施用後 土壤의 칼슘含量은 全般的으로 增加하였으며 葉內의 칼슘含量도 石灰 施用量과 比例하여 增加하였다. 2. 土壤 pH는 石灰施用前에 5.6∼6.0 이었으나 石灰施用後에는 6.0∼6.4로 높아졌다. 따라서 염基飽和度도 pH와 같은 傾向으로 높아졌다. 3. 石灰를 施用하므로써 技條의 先端枯死를 어느程度 防除할 수 있었다. 4. 石灰의 施用은 뽕나무 오갈병의 發病率을 낮출 수 없었다. 5. 石灰를 施用하므로써 11∼13%의 收量이 增大되었다. The effect of lime application on the leaf yield in the mulberry field was investigated. Four levels of lime CaO 0, 100, 200, and 300Kg/10a was applied. The calcium quantity in the soil after lime application was increased, accordingly pH and degree of base saturation in the soil were increased. The winter injury of the top stems was decreased by the application of lime and the yield of muiberry leaves was increased by 11-13%, compared with those for the non-application of lime.
김낙근 ( Nak Geun Kim ),이계복 ( Kye Bock Lee ) 충북대학교 건설기술연구소 2012 建設技術論文集 Vol.31 No.1
항구로 바닷물이 들어올 때 수문의 자려 진동은 수문 아래의 와류에 수문의 자려진동을 예측하기 위해 2차원 비정상 유동 특성을 수치적으로 해석하였다. 의해 발생하는 것을 확인하였다. 진동수와 평균속도에 대한 수문개도의 영향과 수문 아래에 발생하는 와류에 대해 연구하였다. 수문 개도가 증가할수록, 진동수는 감소하였다. Numerical analysis on the flow induced vibration in the water gate has been carried out by 2-dimensional unsteady CFD simulation when sea water flows into the port in the river. The results show that the sources of disturbed frequency are the vortex shed from the bottom of the water gate. Effect of gate opening on the frequency and the mean velocity and the vortex shed from under the water gate were studied. As the gate opening ratio increases, the predicted vibration frequency decreases.