科创中国

利用第一性原理方法研究了一系列正交结构锰酸盐Gd1-xHoxMnO3(0.0≤x≤0.5)的电子结构和磁学性质.我们研究的所有组分的Gd1xHoxMnO3都能保持单一的立方结构,单胞的体积也随着x的增大线性减小,Mn -O - Mn键的键角也随着Ho的掺杂而线性的减小.我们的磁属性研究表明随着Ho的掺杂反铁磁-E相变越来越稳定,Mn的磁矩随着x的增大基本不变.

Steering control of a capsule robot in curve environment by magnetic navigation is not yet solved completely.A petal-shaped capsule robot with less steering resistance based on multiple wedge effects is presented,and an optimization method with two processes for determining the orientation of a pre-applied universal magnetic spin vector is proposed.To realize quick and non-contact steering swimming,a fuzzy comprehensive evaluation method for optimizing the steering driving angle is presented based on two evaluation indexes including the average steering speed and the average steering trajectory deviation,achieving the initial optimal orientation of a universal magnetic spin vector.To further reduce robotic magnetic vibration,a main target method for optimizing its final orientation,which is used for fine adjustment,is employed under the constrains of the magnetic moments.Swimming experimental results in curve pipe verified the effectiveness of the optimization method,which can be effectively used to realize non-contact steering swimming of the petal-shaped robot and reduce its vibration.

Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries.The two kinds of actuators can replace each other in most fields,such as the point to point transmission occasion and some rotating occasions.However,there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far.In this paper,a novel comprehensive assessment method,named as overall life cycle comprehensive assessment(OLCCA),is proposed for comparison and assessment of pneumatic and electric actuators.OLCCA contains mechanical properties evaluation(MPE),life cycle cost analysis based on users(LCCABOU)and life cycle environmental impact analysis(LCEIA)algorithm in order to solve three difficult problems:mechanical properties assessment,cost analysis and environmental impact assessment about actuators.The mechanical properties evaluation of actuators is a multi-objective optimization problem.The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators.Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm.The case study of MPE algorithm for actuators verified its correctness.LCCABOU for actuators is also set up.Considering cost complex structure of pneumatic actuators,public device cost even method(PDCEM)is firstly presented to solve cost division of public devices such as compressors,aftercooler,receivers,etc.LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators.Finally,LCEIA model of actuators is established for the environmental impact assessment of actuators.LCEIA data collection method and model establishment procedure for actuators are also put forward.With Simapro 7,LCEIA comparison results of six actuators can be obtained:Fossil fuels are the major environmental factor of pneumatic and electric actuators;Environmental impact of electric actuator is large than one of pneumatic actuator under the similar mechanical properties and working conditions of pneumatic and electric actuators.The results are correct and correspond with the actual mechanical properties of actuators.This paper proposes a comprehensive evaluation method of the actuators,which can solve the critical problem that similar electromechanical products are very difficult to be compared with each other from the angle of performance,cost and environment impact.

目的通过分析磁共振T1WI-SPIR序列半月板撕裂的征象并与关节镜结果对比以探讨其在半月板撕裂诊断中的临床应用价值.方法回顾性分析45例经关节镜证实的半月板撕裂病人T1WI-SPIR表现并与关节镜结果对比.结果45例90个半月板T1WI-SPIR诊断撕裂70个,关节镜证实50个,MR敏感性100%,准确率71%.结论磁共振T1WI-SPIR序列诊断半月板撕裂较为敏感,但存在一定假阳性.

针对为胶囊内窥镜供能的无线能量传输技术在应用过程中对人体组织可能造成伤害的问题,进行了无线能量传输系统发射线圈优化设计研究.分析了人体组织安全性与无线能量传输系统发射线圈之间的关系,提出用磁场均匀度、频率稳定度等指标来评价发射线圈性能,并建立了以能量传输效率为目标函数、以人体安全性和能量需求为约束条件的最优化模型.该模型可用来全面评价发射线圈性能,从而为发射线圈的设计提供依据.采用上述方法对4种类型的发射线圈进行了评价,评价结果证明了该方法的可行性.

目的研究急性胰腺炎磁共振严重度指数(MR Severity Index,MRSI)与急性生理与慢性健康状况评分系统(the Acute Playsiology And Chronic Healthy Evaluation,APACHEⅡ)之间的相关性,探讨是否可以利用MRSI来评估急性胰腺炎的严重程度.方法回顾性分析119例急性胰腺炎患者的MRI表现.每侧AP息者在MR上的严重程度用MR严重程度指数(MR Severity score iridex,MRSI)进行分级,MRSI 0-2分为轻型,3-6分中度,7-10分为重型.同时根据患者的临床和实验室参数对每例患者行APACHEⅡ评分,并对MRSI与APACHEⅡ评分进行相关性分析.结果根据MRSI,119例急性胰腺炎中,轻型急性胰隙炎48例,中度59例,重症急性胰腺炎12例.53例APACHEⅡ≤7分,66例APACHEⅡ≥8分.MRSI与APACHEⅡ评分存在弱的正相关关系(r=0.314,P〈0.01).结论MRSI能在一定程度上反映急性胰腺炎的临床严重程度,应纳入全面评价急性严重程度的评价体系中.