小四轮拖拉机离合器可靠性的分析与改进

针对近年来小四轮拖拉机普遍存在平均故障间隔时间（MTBF）短的问题,课题组进行了统计分析,确认离合器是薄弱环节。选择碟形弹簧离合器取代圆柱螺旋弹簧压紧离合器,运用参数优化、三维数字化设计、有限元分析（FEM）和数字化虚拟样机（DMu）运动模拟等技术,有效地解决了这一关键问题并实现产业化。     

碟簧支撑圆形瓦推力滑动轴承在临洪东泵站的应用

针对江苏省连云港临洪东泵站采用的新型碟簧支撑圆形瓦推力滑动轴承,论述了其新颖的结构形式、安装使用特点。根据机组零部件加工精度、运输对部件精度的影响、现场安装条件等各种因素,提出了三套蝶簧支撑圆形瓦推力滑动轴承机组的安装方案,通过比较分析,明确了精调定子水平、综合处理下导摆度安装的施工工艺。临洪东站12台机组的安装表明新的安装工艺减少了机组安装工作量,缩短了工作时间,提高了机组安装质量,达到了安装规范的要求。     

主被动联合遥感云雨分布的研究进展

简要介绍了雷达和微波辐射计测量云雨分布的发展过程、测量原理和优缺点,进而介绍了主被动联合遥感方法的测量原理和主要优势;然后,对联合方法的误差来源进行了全面的讨论,如实时背景的选择、背景无雨辐射亮温的选取、雷达波雨（云）区衰减均会对反演结果造成较大影响;最后,说明了联合方法应用于实际观测时的一些局限性和可能的改进办法。结果表明,联合方法无论是从理论上还是从技术上都是可行的,且有较高的测量精度,在定量测量云雨分布中可发挥巨大作用,具有很大的发展潜力,这对洪涝灾害预警和水库合理蓄放等与农业发展息息相关的重大国民经济问题意义重大。     

单品种淡水活鱼数量的被动声学估计

针对单品种淡水活鱼数量估计问题,以鲫鱼和鳊鱼为研究对象,采用不同数量淡水鱼的被动水声信号作为样本,通过4~6层小波包分解算法,对比分析了样本的若干特征提取方案,明确了鲫鱼水声信号特征的提取方案为短时平均过零率+6层小波包分解频段能量,而鳊鱼只需提取6层小波包分解频段能量作为其信号特征。根据不同样本集划分方法比较结果,确定了鲫鱼样本集划分方法为Rank-SPXY(m=10),鳊鱼为Rank-SPXY(m=5)。利用竞争自适应重加权采样,筛选出样本的关键特征,并使用多元线性回归和偏最小二乘回归建立了若干淡水活鱼的数量估计模型,结果表明:多元线性回归模型的性能较好,鲫鱼和鳊鱼数量估计模型的复相关系数分别为0.835和0.893,相对分析误差分别为1.79和2.01。     

非线性复微分方程的解与Hω∞空间

利用直接的积分估计,研究非线性复微分方程(f~(k))~(n_k)+A_(k-1)(z)(f~(k-1))~(n_(k-1))+…+A_1(z)(f′)~(n_1)+A_0(z)f=Ak(z)解的函数空间属性,刻画了方程的解析解,以及它们的导数属于H∞ω空间时系数需要满足的条件.改善及推广了已有的相关结果.     

Evaluation of T2‐weighted versus short‐tau inversion recovery sagittal sequences in the identification and localization of canine intervertebral disc extrusion with low‐field magnetic resonance imaging

Sagittal T2‐weighted sequences (T2‐SAG) are the foundation of spinal protocols when screening for the presence of intervertebral disc extrusion. We often utilize sagittal short‐tau inversion recovery sequences (STIR‐SAG) as an adjunctive screening series, and experience suggests that this combined approach provides superior detection rates. We hypothesized that STIR‐SAG would provide higher sensitivity than T2‐SAG in the identification and localization of intervertebral disc extrusion. We further hypothesized that the parallel evaluation of paired T2‐SAG and STIR‐SAG series would provide a higher sensitivity than could be achieved with either independent sagittal series when viewed in isolation. This retrospective diagnostic accuracy study blindly reviewed T2‐SAG and STIR‐SAG sequences from dogs (n = 110) with surgically confirmed intervertebral disc extrusion. A consensus between two radiologists found no significant difference in sensitivity between T2‐SAG and STIR‐SAG during the identification of intervertebral disc extrusion (T2‐SAG: 92.7%, STIR‐SAG: 94.5%, P = 0.752). Nevertheless, STIR‐SAG accurately identified intervertebral disc extrusion in 66.7% of cases where the evaluation of T2‐SAG in isolation had provided a false negative diagnosis. Additionally, one radiologist found that the parallel evaluation of paired T2‐SAG and STIR‐SAG series provided a significantly higher sensitivity than T2‐SAG in isolation, during the identification of intervertebral disc extrusion (T2‐SAG: 78.2%, paired T2‐SAG, and STIR‐SAG: 90.9%, P = 0.017). A similar nonsignificant trend was observed when the consensus of both radiologists was taken into consideration (T2‐SAG: 92.7%, paired T2‐SAG, and STIR‐SAG = 97.3%, P = 0.392). We therefore conclude that STIR‐SAG is capable of identifying intervertebral disc extrusion that is inconspicuous in T2‐SAG, and that STIR‐SAG should be considered a useful adjunctive sequence during preliminary sagittal screening for intervertebral disc extrusion in low‐field magnetic resonance.     

圆盘破茬刀切割玉米根茬运动特性测绘装置设计与试验

免耕播种机是保护性耕作的关键机具之一,其播种质量的好坏在很大程度上影响着保护性耕作的效果。为了优化免耕播种机的关键部件破茬刀,研制了一种圆盘破茬刀切割玉米根茬运动特性测绘装置,该装置能够实现实时地测绘出圆盘破茬刀待测点的运动轨迹。通过对三种圆盘破茬刀的运动轨迹的测绘与试验,得出光面圆盘破茬刀上待测点的运动轨迹为光滑的摆线,半圆型缺口盘和阿基米德螺线盘上待测点的运动轨迹为由不同长度的圆弧组成的云曲线。在此基础上对三种圆盘破茬刀冲击情况、入土滑切角和滑切速度变化进行了分析比较,建立了阿基米德螺线型圆盘破茬刀切割根茬运动的运动学模型。描绘出阿基米德螺线型圆盘破茬刀刃口上点的运动轨迹是由不同长度的圆弧组成的云曲线,建立了阿基米德螺线型圆盘破茬刀刃口上点的运动方程。发现阿基米德螺线型圆盘破茬刀刃口上点的轨迹具备了光面圆盘破茬刀的摆线规律,也具备了半圆型缺口圆盘破茬刀的冲击性,并且滑切角较大,滑切性能更好。通过圆盘破茬刀切割玉米根茬运动特性测绘装置的两因素三水平正交试验分析,得出阿基米德螺线型圆盘破茬刀、机具配重为100 kg时破茬效果达90%以上,破茬率较高。     

Measurement and Analysis of Multi Functional Stadium ofGuangdong College of Pharmacy

Lighting and air conditioning energy consumption of stadium is very large. That how to use natural lighting and natural ventilation is the key pivot for stadium energy efficiency design. A variety of passive energy efficient measures were used in the Multi functional stadium of Guangdong College of Pharmacy, such as lighting windows with vertical blinds in east and west facades, Openable windows on south and north facades, planting roof and etc. It was found that the above mentioned passive designs could 〖JP2〗increase natural illumination of competition venues, prevent the glare, raise wind speed in audience area, improve comfort level and decrease internal surface temperature of affiliated building and reduce heat radiation.     

犬腰椎间盘切除术入路探索

为了探索治疗犬腰椎间盘突出症的合理手术入路,选择2月龄～1岁龄临床健康的本地杂交犬5只,分别编为1号～5号犬,其中1号、2号、3号犬施行半侧椎板切除术,4号、5号犬施行全椎板切除术,手术2周后进行X线摄片并剖检其腰椎结构变化。结果显示,术后1号～3号犬精神状态良好,饮食欲及体温正常,术部切口正常愈合,椎间盘部分或全部髓核被顺利取出;4号、5号犬手术中大出血,经治疗4号犬痊愈,而5号犬因衰弱而死亡。结果表明,腰椎间盘切除术要求严格的无菌操作和有效控制的麻醉,术犬侧卧位保定行半侧椎板切除是良好的手术入路,能够充分显露椎间盘、打开纤维环通道和切除髓核,有利于提高手术的安全性和保持腰椎的完整性与稳定性。     

电针配合药物治疗犬椎间盘突出

近年来,犬椎间盘突出症在宠物临床上越发的常见。由于本病的发病原因较为复杂、发病过程多为慢性,在诊断时难于判断,同时在治疗时以手术疗法为主治愈率较低。临床实践表明应用电针配合药物对该病进行治疗,治愈率大大提高。作者对犬椎间盘突出的病因与诊断进行了阐述,并说明了电针复合药物对该病的治疗机理,为该病的诊断提供系统的理论指导,为电针配合药物治疗方案的推广打下坚实的基础。