从L*-空间构造包囿空间的方法     

张志尧 《天津大学学报(英文版)》2001,7(2):137-139

论了一种在向量空间上构造包囿拓扑的新方法 .收敛序列和有界集一般是拓扑空间中的概念 ,文章首先引入序列收敛 C和 L* -空间 (给出某种序列收敛关系的向量空间 ) ,然后在其中定义有界集 .设 C为一序列收敛关系 ,T (C)是由 C确定的拓扑 ,B(C)是由 C确定的有界集族 ,则有 B(C) =B(T(C) ) ,并进一步从 L* -空间构造了包囿拓扑向量空间  相似文献   

Three‐dimensional printing of X‐ray computed tomography datasets with multiple materials using open‐source data processing          下载免费PDF全文

Ian M. Sander  Matthew T. McGoldrick  My N. Helms  Aislinn Betts  Anthony van Avermaete  Elizabeth Owers  Evan Doney  Taimi Liepert  Glen Niebur  Douglas Liepert  W. Matthew Leevy 《Anatomical sciences education》2017,10(4):383-391

Advances in three‐dimensional (3D) printing allow for digital files to be turned into a “printed” physical product. For example, complex anatomical models derived from clinical or pre‐clinical X‐ray computed tomography (CT) data of patients or research specimens can be constructed using various printable materials. Although 3D printing has the potential to advance learning, many academic programs have been slow to adopt its use in the classroom despite increased availability of the equipment and digital databases already established for educational use. Herein, a protocol is reported for the production of enlarged bone core and accurate representation of human sinus passages in a 3D printed format using entirely consumer‐grade printers and a combination of free‐software platforms. The comparative resolutions of three surface rendering programs were also determined using the sinuses, a human body, and a human wrist data files to compare the abilities of different software available for surface map generation of biomedical data. Data shows that 3D Slicer provided highest compatibility and surface resolution for anatomical 3D printing. Generated surface maps were then 3D printed via fused deposition modeling (FDM printing). In conclusion, a methodological approach that explains the production of anatomical models using entirely consumer‐grade, fused deposition modeling machines, and a combination of free software platforms is presented in this report. The methods outlined will facilitate the incorporation of 3D printed anatomical models in the classroom. Anat Sci Educ 10: 383–391. © 2017 American Association of Anatomists.  相似文献   

一种抗磨减摩添加剂的改进实验研究     

朱建华 《茂名学院学报》2002,12(3):39-41

对一种润滑油添加剂进行了改进实验研究。新的添加剂配方适用范围扩大，性能有所提高，新的添加剂不仅对钢-钢摩擦副效果明显，同时对钢-钢摩擦副也有好的抗磨减摩作用。  相似文献   

润滑油添加剂中试研究现状及发展     

杨克 《兰州石化职业技术学院学报》2012,(4):5-7

润滑油添加剂的中试研究是实现实验室成果向工业化转化的重要过程,中试研究目的是验证和完善实验室确定的反应条件,为工业化设计提供数据。完善中试装置,提高自动控制技术,建立中试基地是润滑油添加剂中试研究的发展方向。  相似文献   

纳米水滑石及其焙烧产物的摩擦学性能初探     

于湘  谢颖  邓伟星  俞志东 《茂名学院学报》2012,(6):7-9

以纳米水滑石及其焙烧产物作为润滑油添加剂,采用四球摩擦试验机测定其摩擦学性质,利用光学显微镜观察摩擦表面磨斑情况。研究结果表明：基础油中加入纳米水滑石及其焙烧产物能够显著降低摩擦副表面粗糙度,减少摩擦阻力;焙烧产物以0．2％质量分数添加时,抗磨减摩性能最好,摩擦系数由0．075降低至0．065。  相似文献   

提高延迟焦化装置液体收率方法     

洪晓瑛 《茂名学院学报》2013,(4):5-8,26

随着原油不断重质化以及人们对轻质油品需求量的不断增加,延迟焦化增液技术将受到更多关注。通过操作条件优化、工艺优化、添加助剂、改进控制系统、掺炼其他组分等方法,能在一定程度上提高液体收率。随着研究工作不断深入,必将会有更简便有效,适用范围更广的提高延迟焦化液体收率的方法出现。  相似文献   

加法范畴的推出范畴的幂等完备化     

连冠勤 《莆田学院学报》2010,17(5)

考虑加法范畴的推出范畴的幂等完备化与加法范畴幂等完备化的推出范畴的关系,进一步证明了Abel范畴的推出范畴的幂等完备化与Abel范畴幂等完备化的推出范畴等价。  相似文献   

复合广义泊松过程的可加性     

邹慧鹏  邓春华 《绵阳师范学院学报》2010,29(5):6-7

广义泊松过程常常出现在顾客成批到达或成批服务的排队问题中。已有文献运用概率母函数的方法证明了广义齐次泊松过程的可加性。在此基础上,该文运用特征函数的方法证明了复合广义泊松过程也具有与广义齐次泊松过程相似的可加性。  相似文献   

基于乘性和加性噪声中指数信号的频率最小二乘估计     

邢婧 《科教文汇》2007,(22)

Estimating the parameter of signals is a very important problem in Statistical Signal Processing. In this paper ,we obtain the least squared estimator of frequency of an exponential signal in presence of both multiplicative and additive noise.  相似文献   

Neural adaptations with sport-specific resistance training in highly skilled athletes     

LARRY JUDGE  CHAD MOREAU  JEANMARIE BURKE 《Journal of sports sciences》2013,31(5):419-427

The aim of this study was to assess the effects of variations in the volume and intensity of resistance training in highly skilled athletes on neural adaptive mechanisms: the maximality and pattern of neural drive. The maximality of muscle activation was measured using a high-resolution sample and hold amplifier to record interpolated twitches. The pattern of neural drive was measured by analysing isometric torque–time curves and electromyographic (EMG) characteristics during the performance of rapid isometric contractions at maximal effort. The volume and intensity of training were varied at 4-weekly intervals to systematically emphasize the development of strength, power and motor performance in 14 highly skilled track and field athletes (e.g. discus, hammer, javelin, shot put and weight). Knee extension strength increased significantly by 15% during steady

maximal isometric contractions and by 24% during rapid isometric contractions at maximal effort after the 16-week training programme (P < 0.05). Increases in EMG amplitude and rate of EMG activation indicated that improvements to the pattern of neural drive occurred with sport-specific resistance training (P < 0.05). The maximality and pattern of neural drive did not change in the control group.  相似文献