一类一致混合超图的上、下色数

本文研究了在l、m固定的情况下,删除完全一致混合超图κ（n,l,m）的若干C-超边和D-超边后其上、下色数的变化.     

一个Steckin加强不等式的两个简易证明

给出了一个加强Steckin不等式的两个简易证明.     

辛亥鼎革士子的政治选择及其对革命的认知——以云南绅耆为例

辛亥鼎革,清季士子大部分以积极的姿态融入民国,即使自况为＂遗老＂、＂遗民＂者,其身份界定亦大有讨论余地,其中曲折甚有探讨之处。以云南绅耆在鼎革之际的政治选择的过程及其对辛亥革命的认知为例,我们可以看到清朝与民国之间存在明显的延续性,民国建立的特殊方式,为清季士子接受和进入民国创造了一个更为宽松的环境。     

Upper limb joint muscle/tendon injury and anthropometric adaptations in French competitive tennis players

The purpose of this study was to examine the relationship between the upper limb anthropometric dimensions and a history of dominant upper limb injury in tennis players. Dominant and non-dominant wrist, forearm, elbow and arm circumferences, along with a history of dominant upper limb injuries, were assessed in 147 male and female players, assigned to four groups based on location of injury: wrist (n = 9), elbow (n = 25), shoulder (n = 14) and healthy players (n = 99). From anthropometric dimensions, bilateral differences in circumferences and in proportions were calculated. The wrist group presented a significant bilateral difference in arm circumference, and asymmetrical bilateral proportions between wrist and forearm, as well as between elbow and arm, compared to the healthy group (6.6 ± 3.1% vs. 4.9 ± 4.0%, P < 0.01; ?3.6 ± 3.0% vs. ?0.9 ± 2.9%, P < 0.05; and ?2.2 ± 2.2% vs. 0.1 ± 3.4%, P < 0.05, respectively). The elbow group displayed asymmetrical bilateral proportions between forearm and arm compared to the healthy group (?0.4 ± 4.3% vs. 1.5 ± 4.0%, P < 0.01). The shoulder group showed significant bilateral difference in elbow circumference, and asymmetrical bilateral proportions between forearm and elbow when compared to the healthy group (5.8 ± 4.7% vs. 3.1 ± 4.8%, P < 0.05 and ?1.7 ± 4.5% vs. 1.4 ± 4.3%, P < 0.01, respectively). These findings suggest that players with a history of injury at the upper limb joint present altered dominant upper limb proportions in comparison with the non-dominant side, and such asymmetrical proportions would appear to be specific to the location of injury. Further studies are needed to confirm the link between location of tennis injury and asymmetry in upper limb proportions using high-tech measurements in symptomatic tennis players.     

关于曲面切平面的一些讨论

该文给出了曲面切平面的定义并证明了曲面的切平面存在的充要条件,指出了在函数可微的情况下割平面的极限位置、曲面上所有曲线的切线所在的平面都是切平面,同时提出了若要把割平面的极限位置、曲面上所有曲线的切线所在的平面都作为切平面的等价定义有待证明探讨的问题.     

The effects of forearm fatigue on baseball fastball pitching,with implications about elbow injury

This study investigated the contribution of flexor muscles to the forearm through fatigue; therefore, the differences in forearm mechanisms on the pitching motion in fastball were analysed. Fifteen baseball pitchers were included in this study. Ultrasonographical examination of participants’ ulnar nerve in the cubital tunnel with the elbow extended and at 45°, 90° and 120° of flexion was carried. A three-dimensional motion analysis system with 14 reflective markers attached on participants was used for motion data collection. The electromyography system was applied over the flexor carpi ulnaris, flexor carpi radialis and extensor carpi radialis muscles of the dominant arm. Flexor carpi ulnaris muscle activity showed a significant difference during the acceleration phase, with a peak value during fastball post-fatigue (P = 0.02). Significant differences in the distance between ulnar nerve and medial condyle on throwing arm and non-throwing arm were observed as the distance increased with the elbow movement from 0° to 120° of flexion (P = 0.01). The significant increase of the flexor carpi ulnaris muscle activity might be responsible for maintaining the stability of the wrist joint. The increased diameter might compress the ulnar nerve and cause several pathological changes. Therefore, fatigue in baseball pitchers still poses a threat to the ulnar nerve because the flexor carpi ulnaris and flexor carpi radialis all originate from the medial side of the elbow, and the swelling tendons after fatigue might be a key point.     

基于非对称相似关系的粗集改进模型

改进了基于非对称相似关系的粗集的上、下近似的定义,并从理论上证明了新定义的上、下近似比原来的更合理,并进一步用一个算例来验证。     

LQ-1600K打印头断针维修研究

采用UCDOS6．0中的PATCH24T文件对打印头的24根针进行测试,以确定断针数。然后根据打印头上下两层针的位置图,找到断针所在的位置,从而进行换针操作,使维修工作做到了即简单又准确,具有很强的实用性。     

Lotka-Volterra竞争扩散系统连接边界平衡点和正平衡点行波解的存在性

本文讨论Lotka-Volterra竞争系统连接边界平衡点和正平衡点行波解的存在性。通过变量代换将边界平衡点转化为零点,再利用上下解结合不动点定理得到了当c>c*时行波解的存在性。本文的结果丰富了对Lotka-Volterra竞争系统认识。     

白矮星的质量上限

本文讨论了恒星内部电子兼并压强的公式，然后在此基础上进一步研究白矮星，给出了白矮星质量上限的一个简化推导。