手势识别是人机交互领域的重要研究内容,为截肢患者控制智能假肢手提供基础.当前主流方法之一是利用表面肌电图（Electromyogram, EMG）识别手部运动意图,但肌电信号存在信号弱和易受噪声、汗液、疲劳影响等缺点.同时肌电图在识别准确率方面,尤其是截肢患者手势识别方面仍然具有较大的提升空间.针对这些问题,设计了基于气压肌动图（Pressure-based mechanomyogram, pMMG）的穿戴式信号采集装置,为手势识别提供了优质的信号源.结合深度神经网络中全连接层结构、典型抽样和标准正则化技术,提出了一种改进多类神经模糊推理系统（Improved multicalss neural fuzzy inference system, IMNFIS）,与传统自适应神经模糊推理系统（Adaptive neural fuzzy inference system, ANFIS）相比,泛化能力得到显著提升.招募了7名健康受试者和1名截肢受试者,并用8种算法开展离线实验.所提方法在残疾人手势识别实验中取得了97.25%的最高平均准确率,在健康人手势识别实验中取得了98.18%的最高平均准确率.与近年公开报道的多种手势识别研究相比,所提方法的综合性能更优.

This article carried out the system dynamics modeling and numerical solution for single-stage helical gear transmission mechanism.Continuous hyperbolic tangent function was used for the backlash nonlinear problem;the difficulty of nonlinear problem was transformed into a linear problem.This new method improves the numerical stability,through comparing the influence of the backlash on the gear meshing force and analyzing the displacement response curve so as to provide the basis for improving the accuracy of gear transmission.

近年来,我国市场经济持续繁荣,社会不断进步,科学技术水平也逐渐得到提高,对于机械制造业来说,科学技术的发展为其迎来了有一个新的发展契机.在机械制造业中,机械设计与机械制造技术之间关系密切,息息相关,共同为机械制造业的发展提供强大的动力,根据两者的性质作用来说,机械设计水平的高低影响着机械制造技术的水平,而机械设计又要以机械制造技术为基础,这样才能为提高机械产品的性能提供基础,保障机械制造的质量.机械设计与制造技术在一定程度上决定了制造业的发展前景,能够有效创造财富、促进科技进步.

目的 探讨胆管损伤性狭窄的原因,外科治疗以及疗效.方法 回顾性分析我院1987年至2007年损伤性胆管狭窄54例患者临床资料.结果 54例损伤处理后平均5.6个月内均不同程度的狭窄.对症治疗8例,内镜治疗7例,胆道探查5例,肝总管十二指肠侧侧吻合1例,胆总管空肠侧侧吻合1例,胆管空肠Roux-Y吻合32例.预后评估参照McDon分类,本组失访6例,随访48例中共43例(79.6%)(A＝35,B＝8)长期疗效良好,5例(9.2%)(C＝ 5)术后疗效差.结论 损伤性胆道狭窄首选胆管空肠Roux-Y吻合,其中胆管连续性尚存的低位早期狭窄也可选内镜治疗,效果良好.

Objective To investigate the effects and significance of nerve growth factor(NGF) and its high affinity receptor of tyrosine kinase A(TrkA) expressions on proliferative connective tissue of bile duct in rats after bile duct ligation(BDL).Methods Forty-six female Sprague-Dawley rats were randomly divided into two groups: control group(n=6) and BDL group(n=40).The model of obstructive jaundice in rat was made by bile duct ligation,then duodenohepatic ligament was taken and treated with anti-NGF and anti-TrkA receptor antibody.Expressions of NGF and TrkA receptor in connective tissue of bile duct were investigated by immunohistochemistry,blood specimens were collected from left ventricle to detect serum total bilirubin(TB) and alanine aminotransferase(ALT).Results After BDL,TB level obviously elevated in the third day,and continued until the fourteenth day,then descended.By day 21 and 28,it returned to normal level.Compared with normal bile duct,due to bile stasis,an increased thickness of the bile duct wall was observed by microscope which correlated with the proliferation and differentiation of connective tissue cell.NGF and TrkA were expressed by the cell membrane and the cytoplasm of connective tissue cell and inflammatory infiltration cell after BDL.The trend between their expressions and bilirubin levels was similar.Conclusion NGF and its receptor TrkA regulate the proliferate and differentiation of connective cell in bile duct.They may play a key role in the formation of bile duct scar,which seems to be hardly reversed by relief of bile stasis in a short time.

一、胆管癌神经浸润机制的研究 胆管癌是起源于胆管上皮细胞的恶性肿瘤.具有恶性程度高,预后恶劣的特点,目前在全世界范围的发病率都逐年增加[1],其具有神经浸润的特点使得在治疗上更为棘手.由于神经浸润与否与术后复发率及预后密切相关,故越来越受到人们的重视.然而目前对于胆管癌神经浸润机制的研究相对较少,且多集中在国内。