锡林刺辊线速比与成纱质量关系的探讨

探讨锡林刺辊线速比对成纱质量指标的影响。在一定的刺辊速度、3种不同的锡林速度下,锡林刺辊线速比分别设定为1.5、2.0和2.5共3种进行试验。在其他工艺相同的条件下分别纺制3种不同线密度的纱线,使用USTER ME100型、USTER ZWEIGLE HL400型和YG063T型测试仪对纱线条干、毛羽和强力指标进行检测。通过采用纱线综合质量分析的方法来评定纱线质量。结果显示:当所纺纱线密度较低时,增加锡林刺辊线速比有利于纱线综合质量的提高;但是当所纺纱线密度较大(29.5tex)时,并不是锡林刺辊线速比越大越好。本次试验的锡林刺辊线速比为2.0时,29.5tex纱线的综合质量最优。

锡林刺辊线速比变化对成纱条干质量的影响

研究梳棉机锡林刺辊线速比变化对棉纱条干质量的影响问题。在5档不同刺辊速度下调节锡林速度,在锡林刺辊线速比分别为1.5、2.0及2.5时,做成纱条干对比试验。结果表明:锡林刺辊线速比为2.0时成纱条干质量最好,为1.5时成纱条干质量最差。认为:合理设定锡林刺辊线速比有助于提高成纱条干质量。

电磁无心夹具外圆磨削线速比的微调

将最新的变频器技术应用到电磁无心夹具的工件电动机上,通过无级变速对外圆磨削的线速比进行微调,改善磨削效果并从中掌握线速比微调的规律。

546超早熟短季棉梳理工艺的优化

为探讨546超早熟短季棉的梳理工艺,利用正交试验的方法,通过调整锡林与刺辊线速比、锡林与盖板隔距、道夫转速3个工艺参数,探讨了不同梳理工艺对生条棉结、短绒率及杂质的影响程度,并进行理论分析。认为降低生条棉结、短绒率及杂质的较合理工艺为锡林与刺辊线速比1.83,锡林与盖板隔距0.18 mm、0.15 mm、0.15 mm、0.15 mm、0.18 mm,道夫转速19 r/min。在此工艺条件下,生条的棉结为56粒/g,短绒率为14.6%,杂质为17粒/g。

拖拉机前轮助推性能试验

在混凝土路面和田间2种情况下,对拖拉机前轮不同负重及前后轮不同线速比分别进行了前轮助推力和牵引效率性能试验,找出了前轮助推的最佳工况。

清梳联梳棉机刺辊部分工艺与结杂短绒关系的探讨

清梳联与传统清棉机—梳棉机的刺辊工艺有区别,贯彻“梳理转移适度,结杂短绒兼顾”的工艺原则,根据原棉短绒等纤维性能以及棉纱质量薄弱环节,通过试验,适度增大锡林:刺辊线速比、刺辊至给棉板隔距,控制生条短绒率和精纱短绒率,有利于提高棉纱强力、条干均匀度、稳定棉节。掌握管纱与筒纱品质关系,将优质筒纱为客户服务。

THE TOPOGRAPHIC PARAMETER SENSITIVITY TO VORTICITY PROPAGATION AND TYPHOON TANGENTIAL VELOCITY CHANGES

A high resolution shallow-water model is designed to study the roles which the topographical parameter and latitudinal basic flow play in the propagation of vortex Rossby waves and typhoon tangential velocity changes. With no latitudinal flow, the horizontal scale effects of island terrain on the vortex Rossby waves propagation show that the disturbance vorticity follows a clockwise island-circulating path more significantly, the local maximum wind speed amplitude reduces more sharply, the maximum mean azimuthally tangential wind spins down more substantially, when the topographic horizontal scale augments. With the latitudinal basic flow, the evolution of local wind and mean velocity are affected by the distance changes between TC and the terrain and the time length of topographic action: the local wind amplitude intensifies and the mean velocity diminishes while the distance is shortening; the opposite is true while TC is away from the terrain gradually.

The step-by-step CFD design method of pressure-compensating emitter

In order to improve the design and research and development (R & D) efficiency of the pressure- compensating drip irrigation emitter,a step-by-step computational fluid dynamics (CFD) design method was proposed based on CFD theory combined with the finite element method. By analyzing its hydraulic performance through the step-by-step CFD method,the prediction pressure-flow curve(p-Q curve) of the pressure-compensating emitter was obtained. Then the test samples were fabricated using rapid prototype and manufacturing(RP & M) technology. The emitters' hydraulic performance experiment was carried out and the experimental p-Q curve was obtained. The step-by-step CFD design method was verified by comparing the experimental p-Q curve with the prediction values,which showed that the prediction values met the experimental results well within the normal range of the emitter's working pressure. On this basis,the effect of the emitter structure on its pressure-compensating performance was studied,which showed that the height of the pressure-compensating region had significant effects on the emitter's pressure-compensating performance. Series products of the pressure-compensating emitter could be designed by changing the region's height.

Fairness Aware Rate Adaptation and Proportional Scheduling for IEEE 802.11 WLANs Using FSE

With its rapid development in the wireless markets, IEEE 802.11 WLAN is experiencing a huge popularity. However, due to the limitation of frequency bandwidth of WLANs, it is essential that the available radio resource should be fully utilized to offer different services to multiple users. In order to maximize system throughput while still guaranteeing the fairness among users, a proportional fairness based algorithm is proposed in this work. Since most of the previous resource allocation algorithms were simply based on the channel conditions without taking into account user's demand, in this paper, we introduce the theory of fuzzy synthetic evaluation(FSE) which also allows us to consider user's demand as an important factor. As such, the fairness among users can be improved based on different users' requirements for services. In addition, a channel state information based rate adaptation scheme is also proposed. Through simulation studies, the results clearly validate that our proposed scheme shows advantages on providing user fairness while still improving the system throughput.

Graphic Processing Unit-Accelerated Mutual Information-Based 3D Image Rigid Registration

Mutual information （MI）-based image registration is effective in registering medical images, but it is computationally expensive. This paper accelerates MI-based image registration by dividing computation of mutual information into spatial transformation and histogram-based calculation, and performing 3D spatial transformation and trilinear interpolation on graphic processing unit （GPU）. The 3D floating image is downloaded to GPU as flat 3D texture, and then fetched and interpolated for each new voxel location in fragment shader. The transformed resuits are rendered to textures by using frame buffer object （FBO） extension, and then read to the main memory used for the remaining computation on CPU. Experimental results show that GPU-accelerated method can achieve speedup about an order of magnitude with better registration result compared with the software implementation on a single-core CPU.

石油化工管道接头橡胶防腐密封材料研究

当前石油化工行业环境越发苛刻,对复杂环境下密封材料性能提出更高的要求。对石油化工管道接头橡胶防腐密封材料展开研究。选取氟橡胶、乙丙橡胶以及无碱玻纤和芳纶等原料,利用压延成张法制备石油化工管道接头橡胶防腐密封材料试件,检测不同条件下试件的邵氏硬度、耐腐蚀性能、拉伸强度与断裂伸长率等。结果显示:在投料顺序为:橡胶液→填料→芳纶→玻纤的条件下,所得料团质地最为柔软,纤维分布最为均匀,并且制备出的试件表层颜色均匀统一,不存在白色斑点现象,横向抗拉强度最大。在压延处理过程中,辊筒线速比为1.03时,所制备试件表层质量较好,不存在毛刺现象;在硫化处理过程中,最优温度、压力和时间参数分别为155℃、12MPa和25min,在氟橡胶与乙丙橡胶的配比4∶2的条件下所制备的试件综合性能最优。