Auxiliary guidance manufacture and revealing potential mechanism of perovskite solar cell using machine learning

To promote the development of global carbon neutrality,perovskite solar cells(PSCs)have become a research hotspot in related fields.How to obtain PSCs with expected performance and explore the potential factors affecting device performance are the research priorities in related fields.Although some classical computational methods can facilitate material development,they typically require complex mathematical approximations and manual feature screening processes,which have certain subjectivity and one-sidedness,limiting the performance of the model.In order to alleviate the above challenges,this paper proposes a machine learning(ML)model based on neural networks.The model can assist both PSCs design and analysis of their potential mechanism,demonstrating enhanced and comprehensive auxiliary capabilities.To make the model have higher feasibility and fit the real experimental process more closely,this paper collects the corresponding real experimental data from numerous research papers to develop the model.Compared with other classical ML methods,the proposed model achieved better overall performance.Regarding analysis of underlying mechanism,the relevant laws explored by the model are consistent with the actual experiment results of existing articles.The model exhibits great potential to discover complex laws that are difficult for humans to discover directly.In addition,we also fabricated PSCs to verify the guidance ability of the model in this paper for real experiments.Eventually,the model achieved acceptable results.This work provides new insights into integrating ML methods and PSC design techniques,as well as bridging photovoltaic power generation technology and other fields.

Wireless Bioradar Sensor Networks for Speech Detection and Communication

Wireless multimedia sensor networks (WMSN) are emerging to serve for the collection of acoustic and image information. In the WMSN, the microphone is usually employed to function as sensor nodes for the acquisition of acoustic data. However, those microphone sensors are needed to be placed close with sound source and cannot detect sound signal through certain obstacles. To overcome the shortcomings of microphone sensor, we develop a new type of bioradar sensor to achieve non-contact speech detection and investigate theoretically the mechanism of bioradar for speech detection. Results show that the system can successfully detect speech at some distance and even through non-metallic objects with certain thickness. In addition, in order to suppress the noise and improve the quality of the detected speech, we use spectral subtraction and Wiener filtering algorithm respectively to enhance the bioradar speech and evaluate the performance of the two methods using spectrogram.

A Novel Airborne 3D Laser Point Cloud Hole Repair Algorithm Considering Topographic Features

Hole repair processing is an important part of point cloud data processing in airborne 3-dimensional(3D)laser scanning technology.Due to the fragmentation and irregularity of the surface morphology,when applying the 3D laser scanning technology to mountain mapping,the conventional mathematical cloud-based point cloud hole repair method is not ideal in practical applications.In order to solve this problem,we propose to repair the valley and ridge line first,and then repair the point cloud hole.The main technical steps of the method include the following points:First,the valley and ridge feature lines are extracted by the GIS slope analysis method;Then,the valley and ridge line missing from the hole are repaired by the mathematical interpolation method,and the repaired results are edited and inserted to the original point cloud;Finally,the traditional repair method is used to repair the point cloud hole whose valley line and ridge line have been repaired.Three experiments were designed and implemented in the east bank of the Xiaobaini River to test the performance of the proposed method.The results showed that compared with the direct point cloud hole repair method in Geomagic Studio software,the average repair accuracy of the proposed method,in the 16 m buffer zone of valley line and ridge line,is increased from 56.31 cm to 31.49 cm.The repair performance is significantly improved.

A coaxial-slot antenna for invasive microwave hyperthermia therapy

When the technique of invasive microwave hyperthermia is applied to cancer treating, the distribution of microwave thermal field and the effect of the therapy are determined by the type of microwave radiative antenna. The thermal field of biological tissue produced by microwave radiative antenna is investigated in this paper. The distribution of thermal field and specific absorption rate (SAR) of invasive coaxial-slot antenna in the frequency of 2450 MHz are obtained by the technique of finite element analysis. According to the experiment of heating the ex vivo pork liver by this kind of antenna, the result concordant with the theory is obtained. Therefore, it is suggested that this research could be a reference for clinical therapy and operation scheme.

The evidence of Sm-Nd isochron age for the early Paleozoic ophiolite in Mangya area,Altun Mountains

The REE patterns of the basic volcanic rocks in Mangya area, Altun, are slight rich in LREE with (La/Ya)-N=1.69-3.20, (La/Sm)-N=1.37-1.87, other trace element ratios of the rocks are Th/Ta≈1 (for a few samples greater than 1.5), Nb/Y=0.34-0.62, Ti/Y=310-443 (on the average: 381), Ti/V=37-62, Zr/Nb=9.4-12.4, Sr/Rb=12-80 (on the average: 37), and Nb/Th=7.7-16.8. These features are similar to that of E-MORE or OIB. The ε Nd(t) value, being 3.95- 4.12, shows that the source of the volcanic rocks is derived from depleted asthenosphere mantle mixed with materials from enriched mantle. These, together with the information of geological setting and rock assemblages, indicate that the basic volcanic rocks are of ophiolite. The Sm-Nd isotope ages for the eight basic volcanic rock samples construct a straight line with good correlation, and the calculated isochron age is (481.3±53) Ma. Besides, the eight calculated ε Nd(t) and model ages are close to each other, which suggests that they are homologous, so the isochron is not a mixed line. In the meantime, the isochron age ((481.3±53) Ma) is lower than the model ages (T DM=1 004-1 534 Ma) of the samples, suggeting that the isochron age represents the formation age of the basic volcanic rocks and the ophiolite belt in Mangya area, Altun is formed in the early Paleozoic (Cambrian-Ordovician). In spite of the greater uncertainty of the age, it is still reliable because it is consistent with the age constrained by the regional strata.

Magnetic characteristics and their paleoclimatic significance of Fengzhou loess in the Qinling Mountains of China

The Fengzhou loess section is very typical in the Qinling Mountains. The section, about 82 m thick and underlain by the Neogene red clay, consists of 33 layers of loess and 33 layers of paleosol. The section covers Brunhes normal polarity zone and Matuyama reversed polarity zone, and the B/M boundary is located in the middle of L\-8. Matuyama reversed polarity zone records Jaramillo, Olduvai and Reunion normal polarity subchrons. The boundary between Matuyama reversed polarity zone and Gauss normal polarity zone (M/Ga) appears in the lithological boundary between loess and the Neogene red clay. Loess accumulation in Fengzhou started before 2.48 Ma. The magnetic susceptibility curve indicates 33 cold_dry and humid_warm cycles of paleoclimatic variation in the Qinling Mountains during the last 2.48 Ma. The above climatic fluctuation may be well compared with that of the oxygen isotopic records from deep_sea deposits.