In this work, the costs for machinery and all means for site preparation of forest clearings for afforestation with intensivepoplar plantations were studied by applying various technological schemes. For this purpose,...In this work, the costs for machinery and all means for site preparation of forest clearings for afforestation with intensivepoplar plantations were studied by applying various technological schemes. For this purpose, three technological schemes （TS1,TS2and TS3）, applying in Bulgaria, were studied. By applying the respective technological scheme, the site preparation was performedentirely with a milling aggregate PT-400, equipped with multifunctional forest tiller FAE-300/S. The processes of shredding stumps,mulching clearing debris and bushes, and primary tillage of the soil up to depth of 50 cm were examined. The survey was conductedin poplar clearings along the river Danube, over alluvial moderately moist soil. A new categorization of the poplar clearings isproposed depending on the operating conditions. The performance of the milling unit and the relative costs for labor, machinery andmeans for site preparation per unit area were defined. Depending on the category of poplar clearings, total cost for site preparationapplying the studied technology vary between 27.6 h/ha and 29.3 h/ha, which at current prices of 53.5 ∈/h for the operation of PT-400with FAE 300/S is between ∈1,478/ha and ∈1,569/ha. To conduct comparative analysis of the new technology and the oldtechnologies under similar operating conditions, the relatively costs for site preparation of the previously applied technologies whichuse rotary and tooth uprooter machines are defmed. According to the applied technological scheme and used machines in differentcategories, clearings costs for land preparation vary between ∈1,230/ha and ∈3,300/ha. Based on comparative analysis, it is designeda new technological scheme for afforestation with poplar plantations in riverside clearings, where by ensuring high quality work, thecosts for site preparation become lower （24.2-25.9 h/ha） and thus cost from ∈993/ha to 61,084/ha is achieved.展开更多
医学仿真中的外层组织材质在模拟临床试验、医学科研及教学演示中具有重要的情景再现作用。介绍的一种心脏仿真模型外层材料配方研究,根据区域特点不同,采用了相应实验优化方案。通过正交试验选取了液体硅胶、固化剂、染料用量及固化时...医学仿真中的外层组织材质在模拟临床试验、医学科研及教学演示中具有重要的情景再现作用。介绍的一种心脏仿真模型外层材料配方研究,根据区域特点不同,采用了相应实验优化方案。通过正交试验选取了液体硅胶、固化剂、染料用量及固化时间等4个指标对外表面层材质进行了优化考察,从中得到最佳的心脏仿真模型外层材料配制比例。其中,固化时间权重比例影响最为明显,固化剂用量指标权重影响次之,液体硅胶和染料用量权重影响最小。通过结果满意度排序,最佳配比液体硅胶为100 m L、固化剂为2 m L、染料为17 m L、固化时间为2 h。内表面层材质制备由已有的正交试验实验数据支撑,摸索为单因素变量考查,最佳条件为干燥时间2 h,固化剂量2. 5 m L,液体硅胶量100 m L效果最好。组织功能区域二次修饰经对比实验发现:样品干燥15 min后进行的二次厚涂覆修饰效果最好。展开更多
文摘In this work, the costs for machinery and all means for site preparation of forest clearings for afforestation with intensivepoplar plantations were studied by applying various technological schemes. For this purpose, three technological schemes （TS1,TS2and TS3）, applying in Bulgaria, were studied. By applying the respective technological scheme, the site preparation was performedentirely with a milling aggregate PT-400, equipped with multifunctional forest tiller FAE-300/S. The processes of shredding stumps,mulching clearing debris and bushes, and primary tillage of the soil up to depth of 50 cm were examined. The survey was conductedin poplar clearings along the river Danube, over alluvial moderately moist soil. A new categorization of the poplar clearings isproposed depending on the operating conditions. The performance of the milling unit and the relative costs for labor, machinery andmeans for site preparation per unit area were defined. Depending on the category of poplar clearings, total cost for site preparationapplying the studied technology vary between 27.6 h/ha and 29.3 h/ha, which at current prices of 53.5 ∈/h for the operation of PT-400with FAE 300/S is between ∈1,478/ha and ∈1,569/ha. To conduct comparative analysis of the new technology and the oldtechnologies under similar operating conditions, the relatively costs for site preparation of the previously applied technologies whichuse rotary and tooth uprooter machines are defmed. According to the applied technological scheme and used machines in differentcategories, clearings costs for land preparation vary between ∈1,230/ha and ∈3,300/ha. Based on comparative analysis, it is designeda new technological scheme for afforestation with poplar plantations in riverside clearings, where by ensuring high quality work, thecosts for site preparation become lower （24.2-25.9 h/ha） and thus cost from ∈993/ha to 61,084/ha is achieved.
文摘医学仿真中的外层组织材质在模拟临床试验、医学科研及教学演示中具有重要的情景再现作用。介绍的一种心脏仿真模型外层材料配方研究,根据区域特点不同,采用了相应实验优化方案。通过正交试验选取了液体硅胶、固化剂、染料用量及固化时间等4个指标对外表面层材质进行了优化考察,从中得到最佳的心脏仿真模型外层材料配制比例。其中,固化时间权重比例影响最为明显,固化剂用量指标权重影响次之,液体硅胶和染料用量权重影响最小。通过结果满意度排序,最佳配比液体硅胶为100 m L、固化剂为2 m L、染料为17 m L、固化时间为2 h。内表面层材质制备由已有的正交试验实验数据支撑,摸索为单因素变量考查,最佳条件为干燥时间2 h,固化剂量2. 5 m L,液体硅胶量100 m L效果最好。组织功能区域二次修饰经对比实验发现:样品干燥15 min后进行的二次厚涂覆修饰效果最好。
