Research on rotary geosteering drilling technology and equipment in underground coal mine [PDF]
, 2022 In view of the limitations of directional drilling technology and equipment for underground gas drainage in coal mining areas, such as low degree of automation, low drilling ratio of target formation, slow drilling rate of rock formation, and small ...
Chao XU +7 more
core +1 more source
Position domain control technology for six-joint robots [PDF]
, 2022 In the context of the rapid development of intelligent manufacturing, high-precision motion control of industrial robots has attracted increasing research attention.
Ping-jiang WANG +2 more
core +1 more source
Joint optimization of trajectory and resource allocation for UAV integrated radar and communication system [PDF]
, 2021 For the flexible and efficient area detection and data transmission tasks, the joint optimization of time resource allocation, power resource allocation and the trajectory for UAV (unmanned aerial vehicle) trajectory for airborne IRCS (integrated radar ...
Hui TIAN +4 more
core +1 more source
Study on horizontal completion with composite tubular string in coal reservoir with complex coal structure [PDF]
, 2023 Aiming at the problems such as large deformation difference of coal structure, strong heterogeneity of physical properties, complex coal structure during horizontal drilling, single completion & stimulation technology and so on, a completion technology ...
Baoan XIAN +3 more
core +1 more source
Mechanism and technical system of ground and underground combined drainage of CBM in “four region linkage” in coal mining area [PDF]
, 2022 In order to better realize the safe and efficient coordinated development of coal and CBM resources in high gassy mining areas, the four regions (planning region, preparation region, production region and coal mined-out region) linkage ground-underground
Changjiang JI +4 more
core +1 more source
Thingking and utilization technology of coalbed methane in soft and low permeability coal seams in Huainan Mining Area [PDF]
, 2022 In order to solve the problems that restrict the efficient development of coalbed methane resources under the conditions of soft and low permeability outburst coal seams in Huainan Mining Area, such as complex coal seam structure, multi-source gas ...
Benliang CHEN +8 more
core +1 more source
Dynamic Analysis of the Mechanism with Joint Clearance [PDF]
, 2015 随着工业水平的不断发展，含间隙机构的动力学及其控制的研究逐渐成为了一个热门课题。由于间隙的存在对机械机构的动力学特性造成了一定的影响，所以分析运动副间隙的影响对于机械机构设计和优化的意义就显得十分重大。本文中主要是以具有代表性的含间隙曲柄滑块机构和机械手臂机构为例，来分析间隙以及柔性因素给机械机构动力学特性带来的一些影响。 建立了机械系统的动力学方程，为含间隙机构动力学分析研究提供了理论基础；分析了基于弹簧阻尼模型的Impact接触碰撞函数，为研究轴与轴套间的接触碰撞过程提供了理论依据 ...
牟佳冬
core
Engineering practice of advance gas control for crushed soft coal seams through directional fracturing using a long borehole in the coal seam roof [PDF]
Objective and MethodsThe crushed soft coal seams susceptible to intense coal and gas outbursts exhibit high gas content and pressure. Consequently, during borehole drilling for regional gas pre-drainage in such coal seams, high blowout intensity is prone
Bingyi JIA +3 more
core +1 more source
Development of automatic programming system for near-field electrospinning direct write trajectory [PDF]
, 2011 静电纺丝操作简单、制造成本低、适应范围广，电纺丝纳米纤维性能优越，在柔性电子、生物医学和MEMS等领域受到了广泛的关注。传统的静电纺丝制备得到的纳米纤维呈现无序状态，这给纳米纤维的研究和应用带来了极大的不便和困难。近场静电纺丝技术可实现电纺过程的可控，制备得到排列有序且连续的纳米纤维。基于近场静电纺丝的微/纳米结构直写技术在电纺丝领域中具有广阔的发展前景，而该直写技术的关键是纺丝轨迹控制的实现。本文根据构建的“PC+运动控制卡”开放式数控系统，提出一种用于近场静电纺丝预定轨迹加工的自动编程系统 ...
林志民
core
Research on Moving Net Recovery Technology and Wave-off Decision for Shipborne UAV [PDF]
, 2015 撞网回收是舰载无人机回收的主要方式之一。舰载无人机移动撞网回收的过程复杂、环境恶劣多变，不仅需要高精度的导航系统与制导策略，而且要保证在无法安全完成撞网回收时，舰载无人机能及时准确地复飞，避免撞舰事故的发生。 本文以舰载无人机为对象，研究了移动撞网回收过程的导航策略与末制导律，制定了适用于舰载无人机的复飞策略，并进行了仿真分析及飞行实验。本文的主要工作如下： 首先，本文建立了无人机的六自由度刚体动力学数学模型，搭建了Matlab/Simulink下的非线性仿真环境。通过对样机的配平线性化 ...
张德进
core