摘要：A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is *** dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studied when it is subjected to impact *** to the protection performance for the flexible joint and the pressure change in the fluid bag during the impact process,the sensitivity of the geometric parameters of the fluid bag to the axial stiffness is analyzed by using the orthogonal experimental method,and the optimal parameter combination of the geometric parameters of the fluid bag under impact is obtained,leading to the displacement of the inner shell reduce by 41.4%.The results show that the internal pressure of the fluid bag is a rising process of oscillation and *** sensitivity of the geometric parameters of the fluid bag to the displacement of the inner shell from high to low is as follows:Height H,radius r,wall thickness t,chamfer *** correlation between the geometric parameters of the fluid bag and its internal pressure is:H is negatively correlated with the internal pressure,while the r,t,and A are positively correlated with the internal pressure.

摘要：Accurate classification of EEG left and right hand motor imagery is an important issue in brain-computer interface. Firstly, discrete wavelet transform method was used to decompose the average power of C3 electrode and C4 electrode in left-right hands imagery movement during some periods of time. The reconstructed signal of approximation coefficient A6 on the 6al level was selected to build up a feature signal. Secondly, the performances by Fisher Linear Discriminant Analysis with two different threshold calculation ways and Support Vector Machine methods were compared. The final classification results showed that false classification rate by Support Vector Machine was lower and gained an ideal classification results.

摘要：叉指式背接触硅异质结(IBC-SHJ)太阳电池由于其优异的光学性能备受关注,但是较低的填充因子(FF)限制了其转换效率.本文中,我们用Silvaco TCAD软件模拟了IBC-SHJ太阳电池,发现p-n结和高低结收集载流子的能力有很大差异.高低结内建电场较弱,难以收集电子是FF较低的主要原因.因此,我们用氢化纳晶硅(nc-Si:H)薄膜来代替氢化非晶硅(a-Si:H)薄膜,并且在nc-Si:H薄膜表面覆盖一层超薄高掺杂层进一步提高了载流子传输效率,获得了高达85.3%的FF.此外,三层nc-Si:H薄膜还提高了工艺生产中对掺杂层厚度的容错性,这大大扩展了IBCSHJ太阳电池的工艺窗口.这项工作为解决IBC-SHJ太阳电池的电学问题提供了一条有效的途径,对工艺生产中IBC-SHJ太阳电池的设计具有指导意义.

摘要：Flexible thin-film organic semiconductor devices have received wide attention due to favorable properties such as light-weight,flexibility,reproducible semiconductor resources,easy tuning of functional properties via molecular tailoring,and low cost large-area *** them,ultraflexible electronics,usually with minimum bending radius of less than 1 mm,are essential for the development of epidermal and bio-implanted electronics,wearable electronics,collapsible and portable electronics,three dimensional(3D) surface compilable electronics,and *** review firstly gives a brief introduction of development from flexible to ultraflexible organic semiconductor electronics,and design of ultraflexible devices,then summarizes the recent advances in ultraflexible thin-film organic semiconductor devices,focusing on organic field effect transistors,organic light-emitting diodes,organic solar cells and organic memory devices.

摘要：With the expansion of a city,the urban green space is occupied and the urban heat island effect is *** the roof surfaces of urban buildings is an effective way to increase the area of urban green space and improve the urban ecological *** provide effective data support for urban green space planning,this paper used high-resolution images to(1)obtain accurate building spots on the map of the study area through deep learning assisted manual correction;and(2)establish an evaluation index system of roof greening including the characteristics of the roof itself,the natural environment and the human society *** weight values of attributes not related to the roof itself were calculated by Analytic Hierarchy Process(AHP).The suitable green roof locations were evaluated by spatial join,weighted superposition and other spatial analysis *** the areas within the Chengdu city’s third ring road as the study area,the results show that an accurate building pattern obtained by deep learning greatly improves the efficiency of the *** roof surfaces unsuitable for greening can be effectively classified by the method of feature extraction,with an accuracy of 86.58%.The roofs suitable for greening account for 48.08%,among which,the high-suitability roofs,medium-suitability roofs and low-suitability roofs represent 45.32%,38.95%and 15.73%.The high-suitability green buildings are mainly distributed in the first ring district and the western area outside the first ring district in *** paper is useful for solving the current problem of the more saturated high-density urban area and allowing the expansion of the urban ecological environment.

摘要：This study presents an innovative approach to improving the performance of YOLO-v8 model for small object detection in radar ***,a local histogram equalization technique was applied to the original images,resulting in a notable enhancement in both contrast and detail ***,the YOLO-v8 backbone network was augmented by incorporating convolutional kernels based on a multidimensional attention mechanism and a parallel processing strategy,which facilitated more effective feature information *** the model’s head,an upsampling layer was added,along with the fusion of outputs from the shallow network,and a detection head specifically tailored for small object detection,thereby further improving ***,the loss function was modified to incorporate focal-intersection over union(IoU)in conjunction with scaled-IoU,which enhanced the model’s performance.A weighting strategy was also introduced,effectively improving detection accuracy for small *** results demonstrate that the customized model outperforms traditional approaches across various evaluation metrics,including recall,precision,F1-score,and the receiver operating characteristic(ROC)curve,validating its efficacy and innovation in small object detection within radar *** results indicate a substantial improvement in accuracy compared to conventional methods such as image segmentation and standard convolutional neural networks.