摘要：The purpose of this study was to establish a method for measuring the knee valgus angle from the ana- tomical and mechanical axes on three-dimensional reconstruction imaging models, and to use this method for estimating an average knee valgus angle value for northern Chinese adults. Computed tomographic angiography data in DICOM format for 128 normal femurs from 64 adult subjects were chosen for analysis. After the femur images were subjected to three-dimensional reconstruction, the deepest point in the intercondylar notch （point A）, the midpoint of the medullary cavity 20 cm above the knee-joint line （point B）, and the landmark of the femoral head rotation center （point C） were identified on each three-dimensional model. The knee valgus angle was defined as the angle enclosed by the distal femoral anatomical axis （line AB） and the femoral mechanical axis （line AC）. The average （mean＋SD） of knee valgus angle for the 128 femurs was 6.20°±1.20° （range, 3.05° to 10.64°）. Significant positive correlations were found between the knee valgus angles of the right and left sides and between the knee valgus angle and age. During total knee arthroplasty, choosing a valgus cut angle of approximately 6° may achieve a good result in reestablishing the natural mechanical alignment of the lower extremity for patients of northern Chinese ethnicity. Larger valgus cut angles should be chosen for older patients.

摘要：The photo-induced ultrafast electron dynamics in both anatase and rutile TiO_(2) are investigated by using the Boltzmann transport equation with the explicit incorporation of electron-phonon scattering *** structural parameters required for dynamic simulations are obtained from ab initio *** results show that although the longitudinal optical modes significantly affect the electron energy relaxation dynamics in both phases due to strong Fr?hlich-type couplings,the detailed relaxation mechanisms have obvious *** the case of a single band,the energy relaxation time in anatase is 24.0 fs,twice longer than 11.8 fs in *** discrepancy is explained by the different diffusion distributions over the electronic Bloch states and different scattering contributions from acoustic modes in the two *** for the multiple-band situation involving the lowest six conduction bands,the predicted overall relaxation times are about 47 fs and 57 fs in anatase and rutile,respectively,very different from the case of the single *** slower relaxation in rutile is attributed to the existence of multiple rate-controlled steps during the dynamic *** present findings may be helpful to control the electron dynamics for designing efficient TiO_(2)-based devices.

摘要：A full planar tunable band pass resonator is introduced, which is constructed by using novel symmetric step impedance resonator （SIR） and hyperabrupt varactors for wide bandwidth tuning and size reduction. The equivalent circuit model of the proposed resonator is set up. Theoretical analysis based on transmission line as well as odd and even-mode method is completed. The attractiveness of the approach presented lies in its simplicity. Based on the detailed analysis, a 6 GHz to 10 GHz varactor tuned resonator is designed, fabricated, and measured. It shows wideband tuning ability of 37%. The experimental results of the resonator have a good agreement with the analysis results.

摘要：感应式磁力仪是用于0.01~20kHz空间交流磁场探测的载荷,其传感器由三轴正交的探头组成.由于卫星平台及载荷的独特性和多样性,目前没有通用的地面测试软件.为在发射前对载荷进行全面测试,设计了基于Matlab的数据预处理软件系统,集成波形、幅度和相位多种显示界面,并针对感应式磁力仪信号频带宽、三轴正交等特点研发了多分辨率快速傅里叶变换、滑动平均滤波、相位差计算等数据处理功能.经多阶段实验验证,软件满足对载荷全方位检测及验证要求.

摘要：目前贝叶斯网络缺乏支持结构建立、参数学习、知识推理的一致算法,使知识建立与应用过程无法联接。针对这一现状,通过设计适合于贝叶斯网络学习的遗传算法编码方式、具有调整策略的交叉与变异算子,能进行推理误差反馈的适应函数,实现样本支持下的结构确定、参数学习、推理检验、反馈修正的贝叶斯网络全过程建立。实验结果表明,新算法不仅同步优化网络结构与参数,且可以自适应推理误差的学习修正,有着更满意的知识推理正确率。

摘要：针对机器航天员轴孔装配任务高精度控制要求,提出一种考虑协调操作的力位混合控制方法。在建立含耦合分支的机器航天员动力学方程的基础上,推导轴孔装配过程中双臂协调操作运动约束关系,设计机器航天员考虑协调操作的力位混合控制方法,并通过仿真对控制方法的正确性和有效性进行校验。结果表明:利用本文提出的方法实现了对机器航天员轴孔装配过程中的双臂相对运动以及相互作用力的高精度控制;与传统的未考虑协调操作的力位混合控制方法相比,文中提出的方法在提高控制精度的同时缩短了操作时间,提高了轴孔装配效率。

摘要：设计并制备了结构为掺锡氧化铟(ITO)/氧化锌(ZnO)/纳米多孔硅柱状阵列(NSPA)/Si/Al的纳米异质结发光二极管(LED),实现了近白光电致发光(EL)。利用蒸气刻蚀技术,在P-Si表面制备NSPA层。对NSPA表面进行氧等离子体钝化处理,通过优化钝化参数改善了硅基NSPA的发光特性。在NSPA表面生长N型ZnO薄膜,得到ZnO/NSPA纳米异质结LED。实验结果表明,氧等离子体钝化处理能够有效地提高该器件的发光强度,并实现近白光发射。

摘要：为了研究H型钢异型坯在连铸结晶器内的凝固特性,应用ANSYS有限元软件建立了异型坯连铸结晶器内温度场和应力场耦合模型。运用多载荷步法进行求解实现铸坯的应力遗传行为,描述和分析了凝固坯壳的温度场分布、坯壳生长历程及应力应变变化规律。为分析和解决H型钢异型坯结晶器设计、优化相关工艺和结构参数提供理论依据。

摘要：随着文化产业与旅游产业的深度融合,旅游业的转型发展面临全新的机遇与挑战。红色文化作为我国特有的先进文化,蕴含着丰富的革命精神和深厚的历史文化内涵,成为文旅业持续发展的重要力量源泉。乐亭县是一片红色沃土,以李大钊事迹精神为内核的文化旅游业在这里蓬勃发展,但目前在整合在地资源形成发展合力、创新旅游产品提升游客旅行体验等方面还存在广阔的发展空间。通过对全域体验视角下的李大钊红色文化旅游提升设计进行研究,可以得出全面系统的地域特色旅游发展路径,实现红色资源向实际效益的有效转化,进而带动乐亭全域旅游经济平稳健康发展。

摘要：目的通过拓扑优化和尺寸优化方法对周转铝箱进行轻量化设计,以解决结构强度设计过剩及多工况性能不均衡的问题。方法利用Hyperworks软件对周转铝箱的堆垛工况、运输冲击工况、吊装工况进行有限元分析,对各工况分析结果进行评价。建立基于折衷规划法的多工况拓扑优化数学模型,通过Optistruct软件进行优化求解,获得最优载荷传递路径,并根据拓扑优化结果进行二次设计及有限元分析。最后将新结构的管材壁厚分为7个独立设计变量,通过尺寸优化方法进一步优化管材壁厚。结果有限元分析结果表明基于经验设计的箱体结构安全余量较大,且各工况下的力学性能不够均衡。通过折衷规划拓扑优化设计了新的箱体结构,在同等壁厚下,箱体质量降低10.15%,且提高了横向刚度,使各工况的力学性能更加均衡。结论根据折衷规划模型的拓扑优化方案,使周转铝箱在各工况下的性能得到协同优化,且轻量化设计后的箱体满足多种典型工况的使用要求,说明综合运用折衷规划拓扑优化和尺寸优化的方案是可行的,为金属包装箱的轻量化设计提供了理论依据。