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This paper put forward the overall index of the new point-to-bit type rotary steering drilling tool. It briefly researched the steering mechanism mechanics model (composite beam) and the new point-to-bit type rotary steering drilling tool structure. Based on this fact, it proposes the spline curve prediction blind area trajectory method aim at the blind area existed at the small area of the front end of the drill. The paper discussed the forecast results and probe some laws: as the well depth changes, the inclination of the well path increases, and the azimuth of the well path changes slowly; when the drill build-up rate increases, the inclination angle of the well path increases.

IMO Standards for ship maneuverability require prediction of ship’s maneuvering performance at the design stage. For this purpose, various methods such as those based on free running model tests, captive model tests or numerical simulation using mathematical models can be used. While this paper describes a numerical method for estimating ship’s dynamic stability by computing the linear sway and yaw added mass coefficients using a higher-order panel method based on Non-Uniform Rational B-Spline. Three dimensional forward-speed radiation problems are formulated and solved in frequency domain. The linear hydrodynamic coefficients are calculated and preliminary results are presented for a modified Wigley hull.

Ship launching is an important step in the whole process of ship construction. In modern shipbuilding industry, longitudinal gravity launching method is suitable for most kinds of ships, and is still widely used in many shipyards. Exactly calculation of the ship’s floating state and force acting on the hull and sliders is very important for security of launching ships. The present paper investigated the floating state and hydrostatic force and moment acting on a multi-purpose cargo ship based on some useful data such as Bonjean curves, distribution of ship mass, coefficients of ship form and arrangement of slipway. The variations of buoyancy and draughts at bow and stern with slipping distance are calculated and compared for two cases.

Lithium-deficient thin films Li1-xNi0.5Mn0.5O2 were synthesized by sol-gel method using metal lithium, manganese and nickel acetate salts and acetylacetonate salts as started materials, respectively. The microstructures and electrochemical performance of Li1-xNi0.5Mn0.5O2 thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge–discharge measurements. Lithium-deficient was due to the formation of spinel LiNi0.5Mn1.5O4 impurities. The lithium-deficient was more seriously for SB film due to contain crystal water in the acetate salts. The raw material had great influence on the morphology of the films. The SA film had better electrochemical properties than that of SB film. The first discharge capacity was about 51 μAh/cm2-μm. After 40 cycles, 76% of its discharge capacity can be retained. The metal acetylacetonate salts without crystal water are more suitable for the preparation of LiNi0.5Mn0.5O2 film by sol-gel method.