• Grassland science: 5 groups – grasses, grass­ like plants, forbs, shrubs, and succulents肉质植物 • Forbs: herbaceous, broadleaf plants • Legumes are one type of forb • Other forbs are useful in forage­livestock systems • Forbs are used to fill in gaps in forage production

1.1 Contents of Theory of Elasticity 1.1弹性力学的内容 ·NAME Theory of elasticity is often called elasticity for short. It is the branch of solid mechanics. 弹性力学的理论简称为弹性理论或弹性力学. 它是固体力学的一个分枝

Grass introduction The morphology,biocharacteristic,cultivation and uses of: • Smooth Brome • Ryegrass • Other grasses（Chinese wild­rye, Crested wheatgrass,Tall fescue,orchardgrass,kentucky bluegrass etc.)

2.1 Plane stress and plane strain 平面应力问题与平面应变问题 2.2 Differential equations of equilibrium 平衡微分方程 2.3 Stress at a point. Principal stresses 一点的应力，主应力 2.4 Geometrical equations. Rigid-body displacements 一几何方程，刚体位移 Shear stress trajectories in a cantilever beam 悬臂梁的剪应力轨迹线 2.6 Physical equations. 物理方程 2.7 Boundary conditions 边界条件 2.8 Saint-venant`s principle-1 圣维南原理 2.9 solution of plane problem in terms of displacements 按位移求解平面问题 2.10 solution of plane problem in terms of stresses 按应力求解 2.11 Case of constant body forces 常体力情况 2.12 Airy`s stress function. Inverse method and semi-inverse method 艾瑞应力函数，逆解法，半 逆解法

8.1 Differential equations of equilibrium 平衡微分方程 Plane problems平面问题的平衡方程 do ox+oty/oy+X-0 Otxy/ox+oo oy+Y=0(2.2.2) Spatial problems空间问题的平衡方程

Polar coordinates极坐标 The position of a point P in polar coordinates is defined by the radial coordinate r and the angular coordinateθ. 一点P的极坐标用径向坐标r和角坐标θ表示 P(r,0) displacements:位移:urue strains:应变:

• 1. Species / cultivar selection • 2. Seedbed preparation • 3. Time of planting • 4. Seed treatments • 5. Seeding depth • 6. Seeding rates • 7. Seeding methods Managemant • 8. Pasture renovation • 9. Autotoxicity • 10.Seed year harvest management • 11.Weed control

1.  Concepts: soil, soil fertility, soil texture, soil structure, soil tillage,  mixed  cropping,  interplanting, multiple cropping 2. Soil type and the characters of soil texture and tillage measure. 3.What kind of soil structure is the most ideal in agriculture? why?

Review: Inverse method逆解法 Select satisfying the compatibility equation 设定中,并满足相容方程V4φ=0(2.12.11) find the stress components by由下式求出应力分量 Txy--02d/ (2.12.10) find the surface force components by 由下式对给定坐标的物体求出面力分量

2-1 Preface 2-2 Fluid Static Pressure and Its Characters 2-3 Differential Equation of Fluid Equilibrium 2-4 Equilibrium Fluids in Gravity Field 2-5 Calculation and Measure of Static Pressure 2-6 Relative Equilibrium of Liquid 2-7 Total Pressure Acting on Plane of Static Fluids 2-8 Total Pressure Acting on Curved Surface of Static