Drill sampling has been widely employed as an effective way to acquire deep samples in extraterrestrial exploration. A novel sampling method, namely, flexible-tube coring, was adopted for the Chang'e mission to acqui...Drill sampling has been widely employed as an effective way to acquire deep samples in extraterrestrial exploration. A novel sampling method, namely, flexible-tube coring, was adopted for the Chang'e mission to acquire drilling cores without damaging stratification information. Since the extraterrestrial environment is uncertain and different from the terrestrial environment, automated drill sampling missions are at risk of failure. The principles of drilling and coring for the lunar subsurface should be fully tested and verified on earth before launch. This paper proposes a test-bed for conducting the aforementioned experiments on earth. The test-bed comprises a rotary-percussive drilling mechanism, penetrating mechanism, drilling medium container, and signal acquisition and control system. For granular soil, coring experiments indicate that the sampling method has a high coring rate greater than 80%. For hard rock, drilling experiments indicate that the percussive frequency greatly affects the drilling efficiency. A multi-layered simulant composed of granular soil and hard rock is built to test the adaptability of drilling and coring. To tackle complex drilling media, an intelligent drilling strategy based on online recognition is proposed to improve the adaptability of the sampling drill. The primary features of this research are the proposal of a scheme for drilling and coring a test-bed for validation on earth and the execution of drilling experiments in complex media.展开更多
In order to verify the feasibility of semi-automatic garlic planter with inclined belt program and determine its reasonable operating parameters, the semi-automatic test-bed with inclined belt of garlic transplanting ...In order to verify the feasibility of semi-automatic garlic planter with inclined belt program and determine its reasonable operating parameters, the semi-automatic test-bed with inclined belt of garlic transplanting machine was designed, and the garlic box experiments were conducted. The angle of inclined belt on the test-bed and its running speed were adjustable. Single factor test results showed that the program of the semi-automatic garlic planter with inclined belt was feasible, and the angle of inclined belt and the test bed running speed affected the indicators. Orthogonal experiment results showed that the angle of inclined belt was the main factor affecting the test indicators. It is also found that the best angle was 30 degrees, while the most reasonable running speed was 0.75 Km/h.展开更多
A new simplified removable ground test-bed was designed for testing a certainturbofan engine. The facilities are 5.5 m long, 1.5 m wide, 2.2 m high and not more than 4. 5 t ofits empty weight. There are four rubber wh...A new simplified removable ground test-bed was designed for testing a certainturbofan engine. The facilities are 5.5 m long, 1.5 m wide, 2.2 m high and not more than 4. 5 t ofits empty weight. There are four rubber wheels that could be towed. There is an independentelectrical measurement and control system to test the rotational speed of rotors, the gas pressureof the compressor, the exhaust gas temperature, etc. Cooperated with the oil truck and the electricpower supply truck, the turbofan engine could be preserved on the ground and started to the idlingregime. While running, the parameter of the engine could be recorded, disposed and displayed. Inaddition, the facilities were successfully applied to the plateau experiment in order to researchhow the atmosphere pressure affects the start of engines. Some data are given in the paper.展开更多
为增强振动筛的处理能力,满足钻采过程中的不同工况需求,改善现有钻井液振动筛存在的“筛堵”“跑浆”等问题,提出了一种“直线+变椭圆”的双轨迹钻井液振动筛,并基于离散元方法 (discrete element method, DEM)耦合多体系统动力学(dyna...为增强振动筛的处理能力,满足钻采过程中的不同工况需求,改善现有钻井液振动筛存在的“筛堵”“跑浆”等问题,提出了一种“直线+变椭圆”的双轨迹钻井液振动筛,并基于离散元方法 (discrete element method, DEM)耦合多体系统动力学(dynamics of multi-body system,MBD)的研究方法,对双轨迹振动筛和岩屑颗粒进行联合仿真计算。探究了2种振型下筛网面上的运动轨迹与抛掷指数、筛分过程中多种岩屑颗粒的运动行为以及筛分性能。研究结果发现:变椭圆轨迹下从入料端至出料端筛面的抛掷指数和振动方向角逐渐减小,有利于实现入料端钻井液固液分离与液相透筛,降低出料端岩屑颗粒的破碎和堵筛概率;稳定筛分时,易透筛颗粒基本处于料层底部或已经透筛,难透筛和不透筛颗粒处于料层的中上层;变椭圆轨迹下多种岩屑颗粒的透筛率均高于直线轨迹、平均透筛时间均短于直线轨迹、平均运移速度均大于直线轨迹。研究成果可为钻井液振动筛的性能提升提供参考。展开更多
目的对鼻咽癌放疗后吞咽障碍患者分别实施Shaker训练和下颏抗阻力(chin tuck against resistance,CTAR)训练,分析三种训练对患者的影响。方法选择2017年2月—2019年2月厦门大学附属第一医院收治的84例鼻咽癌内镜手术后化疗患者为研究对...目的对鼻咽癌放疗后吞咽障碍患者分别实施Shaker训练和下颏抗阻力(chin tuck against resistance,CTAR)训练,分析三种训练对患者的影响。方法选择2017年2月—2019年2月厦门大学附属第一医院收治的84例鼻咽癌内镜手术后化疗患者为研究对象,按随机数字表法将患者分为对照组、Shaker组以及CTAR练组,每组各28例。三组均进行常规吞咽训练,Shaker组联合Shaker训练,CTAR组联合CTAR训练。分析三组患者吞咽能力、日常生活质量、康复治疗效果以及并发症情况。结果干预前三组患者电视透视检查(video fluoroscopy swallowing study,VFSS)评级、功能性经口摄食量表(functional oral intake scale,FOIS)评级以及吞咽障碍特异性生活质量量表(swallowing-quality of life,SWAL-QOL)评分比较,差异无统计学意义(P>0.05)。干预后Shaker组和CTAR组患者VFSS评分低于对照组,FOIS和SWAL-QOL评分高于对照组,差异有统计学意义(P<0.05)。Shaker组和CTAR组之间各评分比较,差异无统计学意义(P>0.05)。对照组患者治疗总有效率为71.43%,Shaker组患者治疗总有效率为92.86%,CTAR组患者治疗总有效率为96.43%。对照组的治疗有效率明显低于Shaker组和CTAR组,差异有统计学意义(P<0.05)。Shaker组和CTAR组治疗总有效率比较,差异无统计学意义(P>0.05)。对照组、Shaker组以及CTAR组并发症发生率分别为32.14%、7.14%以及3.57%。对照组明显高于Shaker组和CTAR组,差异有统计学意义(P<0.05);Shaker组与CTAR组比较,差异无统计学意义(P>0.05)。结论Shaker和CTAR训练均能有效缓解鼻咽癌放疗后患者的吞咽障碍症状,提高摄食功能,并发症较少,改善患者预后。展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51105092)Introducing Talents of Discipline to Universities(111 Program,Grant No.B07018)+1 种基金Heilongjiang Postdoctoral Grant(Grant No.LBHZ11168)China Postdoctoral Science Foundation(Grant No.2012M520722)
文摘Drill sampling has been widely employed as an effective way to acquire deep samples in extraterrestrial exploration. A novel sampling method, namely, flexible-tube coring, was adopted for the Chang'e mission to acquire drilling cores without damaging stratification information. Since the extraterrestrial environment is uncertain and different from the terrestrial environment, automated drill sampling missions are at risk of failure. The principles of drilling and coring for the lunar subsurface should be fully tested and verified on earth before launch. This paper proposes a test-bed for conducting the aforementioned experiments on earth. The test-bed comprises a rotary-percussive drilling mechanism, penetrating mechanism, drilling medium container, and signal acquisition and control system. For granular soil, coring experiments indicate that the sampling method has a high coring rate greater than 80%. For hard rock, drilling experiments indicate that the percussive frequency greatly affects the drilling efficiency. A multi-layered simulant composed of granular soil and hard rock is built to test the adaptability of drilling and coring. To tackle complex drilling media, an intelligent drilling strategy based on online recognition is proposed to improve the adaptability of the sampling drill. The primary features of this research are the proposal of a scheme for drilling and coring a test-bed for validation on earth and the execution of drilling experiments in complex media.
文摘In order to verify the feasibility of semi-automatic garlic planter with inclined belt program and determine its reasonable operating parameters, the semi-automatic test-bed with inclined belt of garlic transplanting machine was designed, and the garlic box experiments were conducted. The angle of inclined belt on the test-bed and its running speed were adjustable. Single factor test results showed that the program of the semi-automatic garlic planter with inclined belt was feasible, and the angle of inclined belt and the test bed running speed affected the indicators. Orthogonal experiment results showed that the angle of inclined belt was the main factor affecting the test indicators. It is also found that the best angle was 30 degrees, while the most reasonable running speed was 0.75 Km/h.
文摘A new simplified removable ground test-bed was designed for testing a certainturbofan engine. The facilities are 5.5 m long, 1.5 m wide, 2.2 m high and not more than 4. 5 t ofits empty weight. There are four rubber wheels that could be towed. There is an independentelectrical measurement and control system to test the rotational speed of rotors, the gas pressureof the compressor, the exhaust gas temperature, etc. Cooperated with the oil truck and the electricpower supply truck, the turbofan engine could be preserved on the ground and started to the idlingregime. While running, the parameter of the engine could be recorded, disposed and displayed. Inaddition, the facilities were successfully applied to the plateau experiment in order to researchhow the atmosphere pressure affects the start of engines. Some data are given in the paper.
文摘为增强振动筛的处理能力,满足钻采过程中的不同工况需求,改善现有钻井液振动筛存在的“筛堵”“跑浆”等问题,提出了一种“直线+变椭圆”的双轨迹钻井液振动筛,并基于离散元方法 (discrete element method, DEM)耦合多体系统动力学(dynamics of multi-body system,MBD)的研究方法,对双轨迹振动筛和岩屑颗粒进行联合仿真计算。探究了2种振型下筛网面上的运动轨迹与抛掷指数、筛分过程中多种岩屑颗粒的运动行为以及筛分性能。研究结果发现:变椭圆轨迹下从入料端至出料端筛面的抛掷指数和振动方向角逐渐减小,有利于实现入料端钻井液固液分离与液相透筛,降低出料端岩屑颗粒的破碎和堵筛概率;稳定筛分时,易透筛颗粒基本处于料层底部或已经透筛,难透筛和不透筛颗粒处于料层的中上层;变椭圆轨迹下多种岩屑颗粒的透筛率均高于直线轨迹、平均透筛时间均短于直线轨迹、平均运移速度均大于直线轨迹。研究成果可为钻井液振动筛的性能提升提供参考。